Media Share 9/MEDIASHARE_09.ISO/educatio/weathe.zip/WEATHER.DOC

Text File | 1992-09-29 | 53KB | 831 lines

                          WEATHER PROFESSIONAL V2.0
                            (c) 1992 Tim Vasquez
                               Sep 22, 1992


   Weather Pro 2.0 is a full color EGA-graphics program which plots
high-resolution weather graphic charts.  It gets its information from National
Weather Service data that you capture on any database you prefer -- no longer
are you tied to a specific system (with extra costs) just to get maps.  You
use the program offline, at your leisure, saving you time and money.
   Weather Pro is -not- a cute toy.  It's a slick tool, and it's about the
best one in existence for pilots, amateur weather persons, storm spotters,
storm chasers, and just about anyone who wants to have the upper hand on the
Weather Channel.  It offers some features that are comparable to those seen in
weather forecasting centers and on weather briefing terminals used by the
major airlines.
   The high-resolution base map of North America is the big plus.  It's
plotted in the polar stereographic projection, and on it, you have complete
control over zooming and panning!  You can even get into the geography
database and modify it, say to enhance the coastline, or add highways,
county lines, and air routes.
   There is another file, too, which contains modifiable cities and towns you
can overlay with a keystroke -- perfect to determine whether Northville
Municipal Airfield is getting hit by a storm or just to see if it's raining
over at Grandma's place.
   The radar plotting ability is the major strength of the program.  It
produces charts that are strikingly similar in form to those received by
National Weather Service forecasters over AFOS circuits.  You don't get a
dinky, vague CGA chart -- you get a full-color, almost broadcast-quality
radar composite.  At your option, Weather Pro will overlay maximum tops,
bow echoes, hook echoes, line-echo wave patterns, BWERs, WERs, and other
significant storm features.  It will even outline the exact coordinates
of severe squall lines!  As you can imagine, it does away with those
warped "teletype"-style radar dot maps available on many databases.  If
you've used one of them, you know how difficult it is to locate a city
accurately or plot straight-line routes.
   Weather Pro pioneers surface analysis on the PC.  It adds sky condition,
temperature, dewpoint, sea level pressure, and wind data from hourly surface
reports in the form of standard plots.  You don't get large, oversized plots,
which plague many specialized weather graphics maps seen on professional
databases.  You get a small, meteorologically useful density of data, perfect
for examing small-scale (mesoscale) conditions, along with the option to
either plot ALL reports or let the computer reduce clutter.  You can also
instruct Weather Pro to plot the surface wind only, without the other data, to
get an idea of the surface wind field.  You can't beat it for planning a
flight or a trip.  Fronts and disturbances will stand out perfectly.
   Last but not least, Weather Pro decodes FDHI/FDLO upper-air reports, widely
used by pilots, to plot upper air wind charts.  You choose which level and
valid time you want, and Weather Pro selects the correct data set.  Like the
surface chart, it draws a network of standard station plots.  The results are
sharp.
   Compositing is a state-of-the-art word in many forecast offices today.  It
means being able to overlay radically different types of data on one another,
and it's a key concept in the National Weather Service's new AWIPS (Advanced
Weather Interactive Processing) computer system.  Weather Pro brings this
power to your desk.  For example, you can plot the color radar chart and then
overlay surface data on it, perhaps to find out if that front is driving the
storms or not, or what the winds in a rain area are.  Then you might want to
zoom in really close for a better look at the mesoscale composite, and allow
Weather Pro to fill in more data in that area.  Or you can overlay the
upper-level winds on the squall line to see how the storms will be steered.
Weather Pro offers auto-compositing, too, to memorize your keystrokes when
you're in a rush.
   And it's fast.  On my Gateway 386/25, the North American base map plots in
four seconds.  Take a huge 150,000-byte weather data file.  Sifting through
this mountain of information, Weather Pro plots surface observations in 12
seconds.  Upper-level wind data takes about 7 seconds.  Radar height data
plots in 8 to 17 seconds.  Due to the complexity of the radar decoding
algorithm, a full-color radar composite takes longer -- about 126 seconds;
but you get to see it at work, and Weather Pro caches the data.  Then, if you
replot the chart in some form or fashion -- zooming, for example -- the same
data will then pop up in 24 seconds.  I certainly don't recommend that you
use Weather Pro on a slow XT model, but you should get acceptable results on
any computer with a graphics card.  And if you have a 486, you'll be flying.
   The catch?  You have to get the data yourself.  To save time and effort,
many terminal programs will let you design a script to automate the process.
Where do you get the data?  YOU decide!  For example, on CompuServe, aviation
weather is part of the basic services -- $8 a month, with no connect charges.
Pilots can use DUAT and Weathermation, which are free.  Weather Pro will sink
its teeth into almost ANY raw data from ANY database.
   The only other catch?  The WeatherPro package runs for $795.
   Not!
   It's $15.  I prefer to make my software affordable and accessable.  No one
likes to pay exhorbitant software prices, and I realize that it just tempts
you to make pirate copies or not register.  If it's worth more to you, though,
I won't stop you from making a contribution.  It's definitely an investment in
updates and improvements.  Also when you do register, you'll get a version
which unlocks the zooming and radar height plotting capability, plus printed
documentation and easy updating.  And if you're on CompuServe, you can chat
with me to discuss improvements and point out any errors and problems you may
have.
   Without a doubt, Weather Pro is one of the most powerful, flexible tools
available to amateur forecasters, pilots, and students.


REQUIREMENTS
   Weather Pro requires a PC or 100% compatible with at least EGA (640 x 350 x
16) graphics.  A 286 (AT) or higher grade computer is recommended to avoid
slow performance.  A hard drive will also speed things up somewhat.  To use
"fast radar" mode, your Weather Pro directory will need about 500K of room
(which will be used ONLY during program execution).
   The other requirement is a source of weather reports.  You will need either
FDHI/FDLO reports, surface aviation reports, or SD radar data.  The data
source should NOT modify the original reports in any way (no "decoded"
reports, for example!).  CompuServe, AccuWeather, Contel DUAT, and
Weathermation are examples of data sources which have been successfully tested
with Weather Pro.

TERMS OF USE
   If you're on any BBSs, feel free to upload and distribute the -demo-
version, WEATHER.ZIP, which is available on CompuServe.  My only restrictions
-- you may not tamper with the content of the Weather Pro demo package in any
way, nor can you sell the package for profit or include it as part of another
package. As far as the -registered- version goes, you may not upload,
distribute, or copy any part of it whatsoever.  It may be installed only on
one computer system at a time.  I know it's tempting to make free copies for
friends, but consider that many long nights have been spent trying to bring
this program into existence. If you like what you see and want powerful
updates and new programs, please encourage others to register.  Shareware is
pure creativity, and it makes the big software companies think twice about
charging outrageous prices.
   THE WEATHER PRO SYSTEM IS PROVIDED WITHOUT WARRANTY OF ANY KIND, EXPRESSED
OR IMPLIED.  The author makes no claims or representation as to its accuracy,
reliability, or fitness for a particular purpose.  The author disavows any
liability connected with the program and documentation. In other words, you
use it at your own risk!  If you need guaranteed precision and reliability,
please consider the thousand-dollar-plus packages produced for the weather
industry.  Although I will try to snuff out all errors and release corrected
updates, you should use Weather Pro with caution and common sense. This
especially goes for you pilots, whose lives depend on the weather -- you
already know that you're required to get a formal weather briefing before
takeoff.  Weather Pro, unfortunately, doesn't constitute one.  Unformatted
weather reports severely test the limitations of any processing method, and
since this is a spare-time project for me, I haven't had the time to explore
every last data string that could cause this program to malfunction.
   If you have any comments, suggestions, or questions, you may send them to
Tim Vasquez at PSC Box 1196, CAFB, IL 61868, or better yet -- how about
CompuServe 71611,2267.


REGISTERING A COPY
   Charging high prices for shareware isn't MY philosophy.  I believe it
should be affordable and creative, not neccessarily a money-making
transaction.  Besides, if it's too expensive, I know you won't bother to
register.  Therefore, I ask only $15 in return for my time and effort, and
I'll make sure you get a good deal. First, I will mail you a registered
program disk, which unlocks the zooming capability and storm height features.
You will get printed documentation, plus a guide to thunderstorm structure and
mesoscale radar interpretation.
   And after that, you get free updates.  I've cleverly designed the software
so that you can update using a demo version available on CompuServe or
elsewhere. You'll never have to re-register just to get a new version!  For
example, the people who ordered the prehistoric version of this program
(RadarScan) are updating their registered program right now with this package.
And if you can't find a demo, just mail me a disk and a SASE disk mailer and
I'll make you a copy, no charge (one at a time, please).  This system also
protects you from price increases. Sound good?  Send a check to Tim Vasquez,
PSC Box 1196, CAFB, IL 61868 to register.  And change your phone number, since
the Weather Channel will probably be calling you for the latest scoop.


OPERATION
   Here's what it takes to use Weather Pro.  Once you get familiar with the
process, you can build batch and script files which automate the entire
process to your own specifications.  And with the right software, you can even
let your PC dial up a new radar map every hour -- automatically!

ACCESS the data.  Using any quality terminal communications program, log into
your database and capture one or all of the following.  It doesn't matter what
order the reports are in, as long as they aren't modified.  Retrieve one or
all of the following:
1. ALL radar reports in the United States for the hour.  This may take about 1
  to 2 minutes at 2400 baud.  You can select certain regions only, but your
  map will be incomplete.
2. As many surface observations as you can get.  There are over 1000 stations,
  and this may take 6 minutes at 2400 baud to download.  You may just want to
  type a list of states, and perhaps some representative stations elsewhere.
3. ALL FDLO/FDHI data for the United States.  This may take about 3 minutes.
  On CompuServe, you can access these data sets by entering GO AWX to go to
  the aviation weather menu.  The commands for retrieving reports is SD @US
  and FDLO @ALL and FDHI @ALL.  You may want to use SA @ALL (includes Canada),
  SA @US (national data only), or simply a list of states, such as SA
  @TX,@OK,@MO to get surface observations.
   On AccuWeather, use commands such as RADU * 1, HRU * 1, etc.  On this and
other databases, consult the user's guide for detailed information on properly
accessing reports.  Be sure that you get, at the minimum, the latest hourly
reports.  Weathermation, for example, will ignore a station's hourly if a
special has been taken recently; you can correct this by specifying a
parameter of one-hour's worth of data. Now for the time.  Radar and surface
reports are not filed at the same time.  Radar reports are filed at :25 past
the hour and surface observations at :55 past the hour.  This causes some
complications.  You should access data between :10 and :20 past the hour, or
:40 to :50 past the hour.  Otherwise, you may get a mixed bag of observation
times.  Weather Pro checks report times carefully, and will throw out
observations that don't conform to the time specified.

CAPTURE the data.  To do this, turn on your "capture" or "disk log" function
to capture the raw radar reports.  Make up any file name.  If you prefer to
let Weather Pro choose the file, capture the data to DATA.TXT in the Weather
Pro directory itself.
   Make sure any existing file is automatically deleted.  Some terminal
programs may append data to the end of a file if it already exists, and this
will eventually cause you problems. As far as the filename, it's best to go
with the default filename used by Weather Pro (normally DATA.TXT, but
modifiable within the program).  But if you like to archive data, you may
prefer to use my own method.  I enter the date for a filename, and the hour
for the file extension.  For example, if I get 22:35 UTC reports for June 8,
1992 (UTC date), I will enter 08JUN92.22Z as a filename.  To clean up my
directories, I can use DOS wildcard commands (for example, DEL ??JUN??.* gets
rid of all June reports).

RUN Weather Pro.  Exit the telecommunications program, change the current
directory to the Weather Pro directory, and enter WEATHER to run Weather Pro.
If you did not save your data to the default filename, append the desired
filename to the command, for example, WEATHER 08JUN92.22Z .


INSIDE THE PROGRAM
   Once the base map has plotted, there are many keys that you can press to
access or manipulate the image.  They can be categorized into movement
commands, overlay commands, and other commands.
MOVEMENT COMMANDS.  Remember that anytime you move the map, the data or
composites must be replotted from scratch.
R - Replot map.  Plots a clean basemap without moving or rezooming the image.
  Cleans the slate, so to speak.  This is useful when you have accidentally
  overlaid an unwanted field on the map.  It also cleans the auto-composite
  slate (to be discussed shortly), erasing memorized dataset choices.
N - National map.  Deselects all zoom settings and starts you out with a
  national map of the United States.
Z - Zoom center.  Centers the map on any station in the WEATHER.STN database.
  You will then be prompted for a map width in miles.  It's recommended that
  you do NOT enter widths of less than 300 miles -- the trigonometry equations
  do not track well on the map projection, and you will end up slightly offset
  from your station.
Page Up/Page Down.  Manually zooms in and out of the map.  This will help
  adjust your zoom.
Cursor Keys.  Moves east, west, north, or south around the region.  It will
  help adjust your map frame.
OVERLAY COMMANDS.  Adds specific data to your map.  It's part of generating a
composite map.
B - Base map overlay.  Simply overlays the base map without clearing the
  screen.  This is helpful if radar echoes are blocking state borders.
C - City overlay.  Overlays cities and towns contained within WEATHER.CTY.
  The overlay uses an automatic anti-crowding algorithm to prevent the cities
  from cluttering each other, so some towns might temporarily disappear on
  wide zooms.
D - Data plot (surface) overlay.  Plots surface data, including sky condition,
  winds, temperature and dewpoint (degrees F), and pressure.  If the
  configuration does not specify "plot all stations", then Weather Pro
  automatically invokes an anti-crowding process to keep stations from
  cluttering each other.
E - Echo overlay.  Overlays radar echoes.  The echoes are plotted in either
  squares or bubbles according to the program configuration; bubbles are
  always faster but squares are more precise.  The process as a whole can be
  lengthy on slow computers.
H - Height overlay.  Overlays maximum echo heights, bounded weak echo regions
  (BWERs), weak echo regions (WERs), line echo wave patterns (LEWPs), bow
  echoes, hook echoes, and hail indications.  LEWP coordinates will be plotted
  on the map using the color specified for the city overlay.  If minimum
  height criteria is specified in the configuration, then all storm tops below
  that height will not be plotted.
S - Surface wind overlay.  Plots the surface wind field.  Note that this does
  not use anti-crowding to reduce clutter.  ALL stations will be plotted
  regardless of settings.
U - Undo radar.  This command will remove the radar echoes without disturbing
  other information on the map.  It's not recommended for slower computers.
W - Winds aloft overlay.  Overlays FDLO or FDHI data from the data file.  You
  will be prompted to enter a height in hundreds of feet MSL (flight level),
  and then a valid time hour (in UTC).  Use the 24-hour military system, not
  the am/pm system.  To convert your time zone to UTC, add 8 hours to PST, 7
  hours to MST, 6 hours to CST, and 5 hours to EST.  If the data for the
  desired hour is not available, this will be indicated at the bottom of the
  map.
OTHER COMMANDS.
X - Configuration.  This will place you in a menu where you can specify your
  desired program preferences.  They will automatically take effect every time
  you run Weather Pro.
T - Time.  Press this to switch to a different observation time in your data
  set.  For example, if you are currently looking at 1355Z observations and
  want to see 1755Z reports, press T and enter 18 for a surface time (1755 is
  actually the 18Z observation).  If you leave it blank, the computer will
  determine the best time to use.  You will also be prompted for a radar
  report time, for example, use an entry of 22 to get 2235Z reports, or leave
  blank to let the computer figure it out.
ESC - Quit.  Returns you to MS-DOS.


SURFACE DATA PLOT
   Weather Pro plots surface data in internationally standardized station
plots.  The circle over the station is shaded according to the amount of cloud
cover.  A wind shaft extends away INTO the wind, and has feathers -- each long
feather indicates 10 knots (11.5 mph), and each short feather indicates 5
knots (6 mph). If there is no feather, a concentric circle is plotted around
the station, indicating calm winds.
   Above and to the left of the circle is the temperature in degrees
Fahrenheit.  Below the temperature is the dewpoint in degrees Fahrenheit --
this is a direct indicator of the amount of moisture in the air.  If you
subtract the dewpoint from the temperature, this gives you the dewpoint
depression, which is indicative of the relative humidity of the air (the less
the dewpoint depression, the greater the relative humidity).  Dewpoint per se
is an accurate measure of how much energy is available to a weather system,
while the dewpoint depression tells how humid the air is and whether fog or
low clouds are possible.
   If weather is occurring, a special data group is inserted between the
temperature and dewpoint.  It starts out with a number describing the
visibility in statute miles (10 = ten miles, 21/2 = two and a half miles,
etc).  The letters indicate the type of weather that is occurring.  They can
be decoded as follows: T thunder, R rain, W shower, S snow, A hail, IP ice
pellets (sleet), L drizzle, Z freezing precipitation, F fog, H haze, K smoke,
BD blowing dust, BN blowing sand, IC ice crystals.  If a + is present, this
indicates that the preceding weather type is intense, a - indicates it is
weak, and nothing indicates moderate. V may be appended to the visibility
number, indicating that the visibility is fluctuating (variable).
   Pressure is located above and to the right of the station circle.  What it
means depends on whether SLP (sea level pressure) or ALSTG (altimeter setting)
is selected.  Sea-level pressure is usually the best parameter for general
weather browsing. If the configuration file specifies that pressures will be
plotted in sea-level pressure, then it will be plotted in tens, hundreds, and
units of a millibar. If the group is above "500", stick a 9 before it; if
below, stick a 10 before it.  Then move the decimal place between the last and
second-to-last digit.  For example, 983 is 998.3 mb, 046 is 1004.6 mb, and 423
is 1042.3 mb.  Sea-level pressure filters out extremes in pressure due to
temperature swings and is more accurate for large-scale analysis, but it's
only available at 95% of weather stations.
   If the configuration specifies that altimeter setting will be plotted,
pressure will appear in units, tenths, and hundredths of an inch.  If the
group is above "500", stick a 2 before it; if below, stick a 3 before it.
Then move the decimal place to the middle.  For example, 983 equals 29.83
inches, 844 is 28.84 inches, and 043 is 30.43 inches.  Altimeter setting is a
true barometer reading, is available at almost every weather station, and is
used by pilots to set altimeters.  It fluctuates markedly with temperature.

WINDS ALOFT PLOT
   Once you select winds aloft from the main menu and enter appropriate data,
Weather Pro will search the data files for FDLO/FDHI reports.  The more
reports there are, the more complete the map will be.
   Similar to the surface wind plots, the shaft points INTO the wind.  Each
triangular feather means 50 knots (56 mph), each long feather means 10 knots
(11.5 mph), and each short one indicates 5 knots (6 mph).
   This data is not only useful to pilots.  The amateur forecaster can look at
the patterns to find jet streams (which are closely associated with frontal
activity), along with waves in the upper-level winds.  When the flow between
20 and 30 thousand feet is predominantly west-to-east, this is called a zonal
flow, meaning that systems tend to be dry and move rapidly.  However, a flow
with numerous dips and rises north and south is called meridional, or
low-zonal. Such a pattern suggests considerable transport of energy and
moisture northward and destabilizing cold air southward, meaning systems
across the country tend to be slow and intense.

RADAR ECHO PLOT
   When Weather Pro plots a radar depiction is plotted, it sifts through the
U.S. weather radar network reports and squeezes out all possible data.  Its
main source of information is from MDR (manually digitized radar) code and
polar-coordinate cell reports in the report.  Outlined echo areas in the
report are not used since they are chunky and often duplicate the MDR data.
The decoding process does take time; it is this process, not the graphics,
that makes it so slow.
   MDR data is a numerical code which describes intensity levels within a
20-mile Cartesian grid (variable with latitude) overlaid on the radar sweep
area.  Using MDR data, Weather Pro builds the best possible image by painting
a "base map" of light precipitation, then discretely painting higher
intensities on top.  The entire process does some time, but this is in order
to produce the best map quality available. The FAA (Federal Aviation
Administration) operates a network of long range air-traffic control radars
across the western United States.  Weather Pro searches through this data,
too.
   Since a single, small radar echo can straddle a grid border, the MDR code
may take more grid boxes than neccessary to define it.  This makes radar
echoes somewhat larger than they really are, an effect known as "blooming".
Although radar operators try to reduce this, it is an inherent drawback of
gridding radar echoes and may be reflected by Weather Pro.

Radar Sites
   Reporting locations which have contributed data to the echo chart are
identified in Weather Pro by a mark or an abbreviation, precisely centered on
the radar site.  It will appear as follows:
+  -- The site is reporting echoes, which have been plotted (the National
      Meteorological Center doesn't do THIS for you!).
NE -- PPINE, Plan Position Indicator No Echoes.  The radar is not detecting
      any echoes.
NA -- PPINA, Plan Position Indicator Not Available.  The radar is off, but is
      otherwise working fine.  The radar operator may be out doing lunch.
OM -- PPIOM, Plan Position Indicator Out for Maintenance.  The Maytag man is
      probably on call.
NS -- PPINS, Plan Position Indicator No Significant echoes.  Echoes are very
      small (cover only 20% or less of the grid box) and do not exceed VIP 1.
      Sort of a "why bother" code.
DE -- PPIDE, Plan Position Indicator Duplicate Echo.  Although the site is
      detecting echoes, a sister radar is reporting them, so no report will be
      made.  Used by the FAA air traffic control centers where the
      meteorologist sees several radar displays at once and can spot potential
      duplication of data.

Echo Plots
   All radars contain VIP (intensity) circuitry which shows the radar operator
the reflective strength of different parts of the echo pattern.  Weather Pro
extracts this from the observation and assigns different colors to the spot.
It's important to remember that most radar dishes are elevated about half a
degree to eliminate ground clutter, so the depictions always show
precipitation about a mile high, not neccessarily what's occurring on the
ground.  If a surface station is reporting no weather under a strong intensity
level, you can bet it's a matter of time before they get clobbered.
   Radar intensities have a direct relation to the amount of rainwater
contained within the cloud.  At high intensity levels, it can be inferred that
a strong convective process is occurring, which often means hail.  However,
the presence of hail means that less rainfall is occurring than otherwise
might be indicated, and it's not even known if the hail is in fact reaching
the ground, so you can never really tell exactly what's going on with such
intense readings.

ECHO                           RAINFALL RATE            TYPICAL
INTENSITY                    (inches per hour)          DESCRIPTION
VIP     LEVEL           Stratiform      Convective      OF ECHO
1       Weak          < 0.10          < 0.20            Light rain
2       Moderate        0.10-0.50       0.20-1.10       Healthy shower
3       Strong          0.50-1.00       1.10-2.20       Thunderstorm
4       Very Strong     -               2.20-4.50       Strong tstm,  hail
5       Intense         -               4.50-7.10       Severe tstm, hail
6       Extreme         -               7.10+           Severe tstm, hail
8       Distant Heavy
9       Distant Light


RADAR HEIGHTS
   If heights are desired (and if the program is registered), Weather Pro will
then sort through the radar reports again.  It will find significant cloud-top
heights and plot these on top of the image.  It also looks for important radar
signatures such as hail, line-echo wave patterns (LEWPs, a dangerous
squall-line pattern), bounded weak-echo regions (BWERS, also known as "vaults"
which indicate tornadogenesis), bow echoes, and tornadic hook echoes.  It
plots the precise location of these features on top of the color map.
   Where does this data come from?  By tilting the radar antenna, the radar
operator can construct a cross section of the thunderstorm on a special
display.  From this, the height of the storm can be determined.  The operator
encodes this onto the outgoing report. On raw reports and in Weather Pro, echo
tops are indicated in hundreds of feet MSL (above mean sea level).  The tops
have a direct relation to the amount of energy available to the storm, but
this does not imply that the storm releases it destructively.  For example, we
might think a 70,000 foot storm would create death and destruction, but weak
"popcorn" storms seen in the southern U.S. during the middle of summer
sometimes reach these heights without any significant severe weather.
   As a general guide, this table will indicate the usual content of storms
based on echo height.  Remember, it's not a book of rules.

HEIGHT  TYPICAL DESCRIPTION
20,000  Normal minimum for a rainshower to become a thunderstorm
30,000  Normal height of summertime popcorn thunderstorms
40,000  Strong thunderstorm with heavy rain and isolated severe wx
50,000  Storm often contains hail, heavy rains, high wind
60,000  Normal height of springtime tornadic thunderstorms, Grt Plains


CONFIGURATION
   The program's configuration values can be modified by selecting the
appropriate keystroke from the main menu. Weather Data Default File.
Indicates where the program will get data if you type WEATHER to run it
without a filename.  This is normally DATA.TXT, but can be modified.  You may
path out of the Weather Pro directory to access the datafile (e.g.
C:\DATA\14JUN92.04Z).
Startup Zoom Location.  This will automatically center the map on this
  location when Weather Pro is executed.  For example, OKC centers on Oklahoma
  City.  If you don't know the station ID, check the file WEATHER.STN to get a
  list of recognized codes.  You may enter a blank entry to center on the
  geographical United States.
Startup Zoom Width.  Sets a width for the map in miles when Weather Pro is
  executed.  To show the entire United States, use a width of about 3400
  miles.  It is suggested that you do NOT use widths of less than 300 miles as
  the program tends to lose its mathematical lock on the selected zoom
  station.
Minimum Height.  Sets a minimum height when storm tops are plotted, in
  hundreds of feet.  Weather Pro will ignore all tops below that level, but it
  will still plot all hail, hook echoes, higher tops, and so forth.  This may
  be helpful if there are many echoes present or your map frequently becomes
  cluttered with height reports.
Plot All Surface Stations.  If "no", Weather Pro will use a special process to
  keep stations from crowding each other on the map.  If "yes", then ALL
  weather stations will be plotted.  Note that this gives Weather Pro a
  license to clutter your map unless you zoom in closely on a particular
  region.
Plot All Radar Echoes During Startup.  Tells Weather Pro whether to auto-plot
  radar echoes when you execute the program.  If you have a slow computer,
  setting this to "no" will speed things up considerably.
Plot Echo Squares Or Bubbles.  Bubbles are faster, but squares are more
  precise.  Try both to see what you prefer.
Alternate Palette.  If "yes", the alternate palette (WEATHER.CO2) is accessed.
  This is helpful, for example, to get a different color set for your screen
  dump program.  This option does not immediately take effect; you must save
  and restart the program.
Fast Radar Mode.  If "yes", all second, third, fourth, etc plots of echoes are
  speeded up considerably.  You must have 500K of room in the Weather Pro
  directory.  Fast mode will disk-cache the radar images so that all of them
  except the first one plot at 5 times their normal speed.  These files are
  deleted when you exit Weather Pro.
Always Plot User-Defined Geography.  If "yes" is selected, Weather Pro will
  include customized geography patterns (highways, roads, airways, county
  lines, etc) on all images.
Always Plot User-Defined Cities.  If "yes" is selected, the program will
  always include cities and towns from WEATHER.CTY on the map.
Plot ALSTG Instead of SLP.  Tells Weather Pro whether to plot altimeter
  setting or sea-level pressure on the surface data plot.
Always Plot Severe Weather from Radar.  If selected, the program will scan the
  radar reports for hook echoes, severe weather, bow echoes, etc and include
  them on every chart.  Note that this is subject to the limitations of the
  radar observing process; there will always be more severe weather than the
  reports indicate, but it will at least clue you in on where significant
  weather is happening.
Overlay Base Map After Plotting Radar.  This option will force Weather
  Professional to overlay the base map after plotting radar echoes.  If you
  don't like having state borders hidden, this option is for you.  If the base
  map plots slow on your system, this option may not be for you.
Auto-Composite Mode.  If auto-composite mode is activated, whenever you build
  a weather map (from echoes, heights, surface data, etc) Weather Pro will
  memorize your choices.  Whenever you move or zoom the map, the selected data
  will automatically be plotted on the new map, saving you keystrokes.  To
  erase memorized settings, use the Replot command.  The only way to disable
  auto-composite mode is to revert the configuration setting.  Auto-composite
  mode is not recommended for slower computers, especially for radar echo
  plots.  Auto-composite will not memorize winds-aloft settings.


CUSTOMIZING THE PROGRAM
   With a little experience with MS-DOS and a bit of spare time, you can
configure Weather Pro for your own setup.  Whether you run an amateur weather
station, fly cross-country, or monitor weather for a company, Weather Pro's
small details can be tailored to your specifications.

Batch Files
   Weather Pro will allow you to use batch files to automate the entire
process.  You may even automate the system completely, having the computer
dial up radar maps every hour, but this requires a memory-resident (TSR)
time-delay program -- fortunately there are such programs available within
CompuServe forums.  Such a program will have to be able to invoke the batch
file automatically and initiate appropriate keystrokes to quit the program.
   If you have a telecommunications program such as Procomm or QModem, you can
write scripts which automatically log into your favorite weather database and
retrieve the radar data.  Then you can link the telecommunications program
with Weather Pro by using a "batch" file.  Batch files simulate keyboard
entries at the DOS prompt, so you can use it to invoke the telecommunications
program with its script, then run Weather Pro immediately.
   Here's an example of a batch file which automates Weather Pro using QModem.
It's assumed that you already have created a script in QModem using their
auto-script feature, and that you save data to C:\WEATHER\DATA.TXT.  It's also
helpful to go into C:\AUTOEXEC.BAT to make sure that a PATH command is
specified to the directory GETRADAR.BAT resides in -- this way, you can call
up the procedure from any directory.

Filename: GETRADAR.BAT
ECHO OFF
C:
CD \QMODEM
QMODEM /S=SCRIPT.SCR
C:
CD \RADAR
WEATHER

   It's not my purpose to give you a DOS tutorial, so for more information
please consult your DOS User's Guide.

Station Listing
   The file WEATHER.STN contains a listing of stations used by Weather Pro in
locating radar and observing sites.  This information is used to plot the
observations and radar echoes.  You can add or delete stations as you like to
modify the density and coverage of reports in desired regions.  Be sure to use
only an ASCII editor such as MS-DOS EDIT to modify this file.
   The three-digit identifier is contained in columns 1-3.  This MUST be in
uppercase and must match the exact identifier used in the radar reports.
Column 6 is normally blank.  If a capital X is here, it means that a surface
report will never be plotted for this station -- it is used only for upper-air
or radar reports.  If a capital C is here, this means that the station is
Canadian and all temperatures/dewpoints will be converted from Celsius to
Fahrenheit. Columns 8-9 contain the latitude of the station in degrees.
Columns 10-11 contain the latitude of the station in minutes.  Columns 13-15
contain the longitude of the station in degrees.  Columns 16-17 contain the
longitude of the station in minutes.  Fill any unused columns with zeroes
(i.e. enter 82 degrees, 5 minutes longitude as 08205).
   If you wish to make adjustments to a preset zoom window, you can "bogus"
this file by inputting a fake radar station, determining the desired latitude
and longitude, and specifying it in the configuration file.  Be sure that you
don't use the identifier of an existing station. You may not have more than
500 stations in this file.  Since a station occupies one row, you can use the
editor to see if the file is more than 500 rows long.

Cities
   All user-defined cities are used only for overlaying, not for locating
data.  You can modify them in RADAR.CTY.  Use any ASCII editor such as MS-DOS
EDIT to modify this file.
   The sample file contains representative stations in the central United
States.  You can delete or modify this file as much as you like, but do not
eliminate it, otherwise you may have problems.  The leftmost three columns
contain the identifier of the city to be plotted.  You can do like I do --
identify airfields by their standard three-letter code, and identify towns and
cities by an arbitrary two-letter system.
   The city identifier is located in columns 1-3.  The city name is located in
columns 6-29 (for your own use only).  Columns 30-31 contain the latitude in
degrees, and columns 33-34 contain the latitude in minutes.  Columns 36-38
contain the longitude in degrees, and columns 40-41 contain the longitude in
minutes.  If there are any unused columns, fill them with zeroes (i.e. write
79 degrees longitude as '079').  See the file itself for an example.

Geography
   All geography can be modified by the user.  There are two geography sets --
the North American "map" set, and the user-defined geography set.  Both are
alike, and are both contained within the file WEATHER.PLT.
   To get inside this file, use MS-DOS's EDIT command or any similar
true-ASCII editor.  Do not use any program which inserts special characters
into the file.
   Each row defines a point and represents the continuation of a line.  When
the latitude/longitude of -1 and -1 is reached, a new "map" line is plotted.
When a latitude/longitude of -2 and -2 is reached, a new user-defined
geography line is plotted.  The difference is that display of the latter set
is optional, based on configuration settings.
   For all entries, simply follow the layout of the existing data as a guide.

Colors
   You don't like the colors?  No problem.  You can adjust them to your own
tastes.  All you need is a text editor.  There are two files containing the
palette -- these are WEATHER.CO1 and WEATHER.CO2.  WEATHER.CO1 is the primary
file used by the program.  When the alternate palette option is selected, the
palette in WEATHER.CO2 is accessed.
   Both files are alike and can be edited with an ASCII text editor such as
MS-DOS's EDIT command.  Here is a breakdown of the file:

ROW     DESCRIPTION
1       Background color value (normally black, 0)
2       Color value for radar intensity level 1 (light precip)
3       Color value for radar intensity level 2 (moderate)
4       Color value for radar intensity level 3 (heavy)
5       Color value for radar intensity level 4 (very heavy)
6       Color value for radar intensity level 5 (intense)
7       Color value for radar intensity level 6 (extreme)
8       Color value for text (storm heights, features, etc)
9       Color value for radar intensity level 8 (distant heavy)
10      Color value for radar intensity level 9 (distant light)
11      Color value for "map" geography and radar status text
12      Color value for miscellaneous graphics (box borders, etc)
13      Color value for city/town/airport geography
14      Color value for "road" geography

Chart of color values.
0       Black   6       Brown   11      Light Cyan
1       Blue    7       Light Gray      12      Light Red
2       Green   8       Dark Gray       13      Light Magenta
3       Cyan    9       Light Blue      14      Yellow
4       Red     10      Light Green     15      White
5       Magenta


TROUBLESHOOTING
   Weather Pro contains many algorithms which are designed to catch human
errors made by those disseminating the radar reports.  While it succeeds in
dodging most of them, you may find a few that slip through the cracks.  So if
you see an echo height of 90,000 feet or a hook echo over Idaho, you might
want to browse through the raw text file using an ASCII editor (such as MS-DOS
EDIT) and correct any deficiencies in the data that you see.  Or, of course,
you can just ignore it.
Q.  The program reads the data file, but no data plots (or some of it plots
      strangely).  What's the deal?
A.  Be ABSOLUTELY sure that your data source does not reformat the reports in
      some manner.  Also check to make sure that your terminal program is in a
      standard configuration and does not strip characters/linefeeds or
      transpose character sets.  If you have further trouble send me a note.
Q.  Weather Pro runs strangely and aborts.
A.  Make sure that you have all Weather Pro files residing within the same
      directory and that you CHANGE DIRECTORY to it before running RADAR.
      Weather Pro will not run if called from another directory.
Q.  Why do the echo squares look so jagged and crooked?
A.  This is how they are mapped -- you're not seeing an error!  When looking
      at the national map, the Cartesian coordinate grid that the squares use
      tends to be slightly rotated from the map grid.  This gives it the weird
      appearance.  Try centering the map over the east coast, and you'll see
      the MDR grid much more easily.
Q.  Weather Pro doesn't plot any data or some plots are clearly erroneous.
A.  BE SURE that your data source and capture utility does not "tamper" with
      the content of the raw reports.  Even something as simple as stripping
      the equal signs (end of report markers) off the ends of the
      observations or adding extra characters will cause problems with the
      program.  It would be nice if the program had pure "fuzzy logic" to
      handle these situations, but such is not the case.  Fortunately, I
      haven't seen any data sources yet which do this.  If you do encounter
      problems, contact me, or write yourself a utility which will
      preprocess the raw data.  If you have found the offending station
      and it is clearly not a one-time coding error, send me an exact
      copy of it and I will try to adjust the program to handle it.
Q.  My customized cities and geography doesn't plot.
A.  You've either not inputted the data correctly, or you're using a non-true
      ASCII editor.  If you're in doubt, ALWAYS use the MS-DOS EDIT command.
      If you've already messed up your file, you will need to delete all your
      entries to strip out the invisible control codes and et cetera.
Q.  When I zoom in close on a station, the map doesn't center on it very well.
A.  I have not devised a formula that converts latitude back from the polar
      stereographic projection, so I am basing screen centers on a sine curve,
      which is close enough.  But if you zoom in very tight, it's bound to be
      off.  This is a known program defect, so use the cursor keys to pan the
      map in the desired direction.  It's not recommended that you use image
      widths of less than a couple of hundred miles.
Q.  How can I send the chart to my printer?
A.  There are so many printer models and "printing languages" out nowadays
      that I decided to wait on any built-in print feature.  You're much
      better off using a TSR (memory resident) program which you can load
      before running Weather Pro.  When you press a certain key, such a
      program will dump the screen image to the printer.  Try the MS-DOS
      GRAPHICS command (read about it in your user's manual), and if this
      doesn't work suitably, access one from many available on CompuServe.
Q.  The chart contains too much data!
A.  If you store, say, 1935Z data in a file, ensure that there is no 1935Z
      data there from another day.  Weather Pro cannot tell the two reports
      apart, and you may get some strange looking maps.  You can avoid this by
      setting up your telecommunications program to destroy any existing
      capture file before opening one with the same name.
Q.  Why is the "system time" printed on the chart and not the date of the
      data?
A.  Weather Pro has no way of knowing whether the data is current or
      historical since this information isn't contained in the file, and the
      file date can be ambiguous.  So it can't really put a date on the chart
      for sure.  But the computer's clock date is listed on the map to help
      you out in case you make printouts and need to refer to them later.
Q.  I get disk errors when I try to install my registered copy of Weather Pro.
A.  If you have trouble installing from the registered disk, it's possible
      that you may be using an old 360K disk drive.  I have copied these from
      a 1.2M disk drive in 360K format.  The write heads on 1.2M disks are
      known to cause minor compatibility problems.  If the problem is
      intermittent, you may want to create your own master disk.  However, if
      you can't get anything to load, send the disk back to me and I'll
      provide a 720K master disk.
Q.  My dog ate my disk.
A.  If you're already registered, send me a blank disk and a SASE disk mailer
      and I'll make you a copy.  I'm not a corporation and I can't
      guarantee you I'll even have a computer 4 years from now, but I'll
      do my best.
Q.  Tell me about the precision of Weather Pro.
A.  The image is only as accurate as the raw data and technical limitations of
      the weather radar network and of Weather Pro's interpretation scheme.
      However, Weather Pro uses precision in handling the data.  All
      coordinates are transformed mathematically through the polar
      stereographic projection formula, so placement error is nominal and is
      subject to the precision of the data.
Q.  Are the radar echoes located accurately?
A.  The national MDR grid is based on the LFM-I grid, the same one used by
      the National Meteorological Center's Cray supercomputers.
      Unfortunately, I don't have their mathematical formula for
      translating Cartesian MDR coordinates to lat/long.  I've tested
      some of my own formulas -- they come close but don't meet my
      standards of precision.  Therefore, all echoes are vector-mapped
      from the radar site using MM as the center location without
      any gridbox offset. Accordingly, the vector direction is adjusted
      to account for the MDR-north declination across the United States.
      Overall, the maximum position error of all echoes relative to
      the real-world is subject to the limitations of the MDR grid (about 20
      nautical miles), plus the deviation of vector-mapping instead of using a
      mathematical MDR grid (about 10 more miles).  It is fairly accurate, and
     the method interestingly removes much of the "blockiness" from the map.
Q.  How accurately placed are the storm tops and features?
A.  Storm features, cloud tops, and so on are mapped exactly as transmitted --
      vector coordinates from the radar site.  Therefore, the error relative
      to the real world is about 1 nautical mile for this data, increasing
      slightly with distance due to azimuth fanning.
Q.  What about state lines and so on?
A.  Geographical boundaries, cities, and et cetera are mapped directly and
      mathematically and should contain no intrinsic error.
Q.  Do the Redskins have a chance this season?
A.  I thought we were talking about weather here.
Q.  Oh.  Well, how do I update my copy if a new version comes along?

UPDATING YOUR COPY
   I've made it easy for you to update your registered copy.
   Whenever I release updates to Weather Pro, I'll make them available on
CompuServe in the form of a demo program.  You should be able to find a copy
in the AVSIG or IBMAPP forum.  All you have to do is download this file and
unzip it in a temporary directory.  Then read the READ.ME file contained in
that update for updating instructions.
   When you run the program, the new Weather Pro will look at the Weather Pro
data files on your disk, since there are data files present which are not
available in the demo version.  If these data files are intact, Weather Pro
will recognize that you are registered and will disable its demo mode.  Users
who don't have the registered copy don't have these data files, and Weather
Pro stays in its demo mode.  If everything looks good, you may want to back up
your directory on a disk and install from that disk if you later have trouble.
   If you have any trouble getting your program to work, check the file
READ.ME in case it contains any special updating instructions.  Note that if
you accidentally delete the data files, Weather Pro may revert to its demo
mode -- in such a case, simply reinstall using the master disks.  If all else
fails, or you can't (or don't want to) update this way, you may send a me a
blank disk (see "dog ate my disk" in Q & A above).
   NOTE:  This policy is not guaranteed, and would only apply to updates of
Weather Professional, not any other weather software program I might create.


IN THE WORKS?
   The main idea considered for Weather Pro includes time-lapse animation.
This is very graphics-intensive and I'll probably have to obtain some
machine-code routines to do this.  It's going to take work.
   Another feature that I hope to add is automatic data-source dialing.  This
is something I could even use myself, but writing routines to control
telecommunications ports has proven more complicated than I thought.
You might also expect improvements in the surface and upper air plotting,
along with the capability to analyze and plot contours on the screen.
Maybe vectors and components, too, for you pilots.
   Last but not least, I'll be looking at compositing of satellite data (with
zooms, moves, etc).  The only question here is "will the typical user really
access all this stuff"?
   I'll also be looking at improving radar echo plotting speed.  It's slow
because it has to be accurate -- there are all kinds of checks and filters for
bad data, but the "fast mode" cache should help you for now.
   Thanks to CompuServe users Robert Kelsoe, Dick Zeitlin, and Scott Dyer for
beta testing.  A -special- thanks to Patrick Rudolph for his extensive
testing, suggestions, and time spent helping to shape this program into what
it is today.


UPDATE SUMMARY

RADARSCAN V1.0   7/04/92.  Initial version.
RADARSCAN V1.1.  7/22/92.  Eliminated processing of extraneous remarks from
  FAA ARTCC radar sites.  Status boxes displayed at bottom of screen while
  program runs.  Added user-defined ability to filter out low cloud tops when
  plotting storm heights.  Slight documentation modifications.
RADARSCAN V1.2   9/8/92.  Not released.  Corrected bug triggered by anomalous
  spacing in end of lines of MDR code.  Enabled plotting echoes as MDR squares
  instead of circles, enabled by /b command.  Added recognition of bow echoes.
  Added ability to plot out LEWP locations.  Stacked legend vertically.  Made
  the time parameter optional -- if absent, RadarScan obtains it from the
  first radar report in the file.  Added color key for VIP levels 8 and 9.
WEATHER PRO V2.0.  9/22/92.  VAST improvement to RadarScan V1.2.  Added
  interactive keyboard control structure, zooming, panning, and scaled back
  command-line parameters.  Added surface, upper air decoding and plotting,
  and a configuration menu.