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- The SELS log is compiled and issued daily by the National Severe Storms
- Forecast Center at Kansas City, MO. It lists reports of severe and
- near-severe weather that they receive (either directly or intercepted)
- from around the 48 contiguous states. Although the events listed are
- in a semi-ordered form, tornadoes are *always* listed first. Here's
- a sample entry decoded:
-
- ZCZC MKCSTADTS
- WWUS60 KMKC 081017
- NSSFC TORNADO AND SEVERE THUNDERSTORM REPORTS
- PRELIMINARY LIST - INTERNAL DISSEMINATION ONLY
- FOR 06CST SUN MAY 7 1989 THRU 06CST MON MAY 8 1989
-
- EVENT LOCATION REMARKS (CST) TIME
-
- 1 A 75 NW PALO PINTO CO TX (15 WSW MWL) ( ----- ) 7/0618
- DIME SIZE HAIL RPTD AT POSSUM KINGDOM FTW/SVS 3273 9833
- RESERVOIR.
-
-
- Event Number: 1
-
- Event: "A" - Hail measured at .75 inches (3/4 of an inch) in diameter.
-
- Location: Northwest Pala Pinto County, TX. Specifically 15 miles west-
- southwest of MWL (Mineral Wells, TX).
-
- Weather watch: ( ----- ) This event did not occur inside a weather watch.
-
- DATE/TIME: 07/0618 OCCURRED ON THE 7TH OF THE MONTH AT 0618 CST.
-
- Details: Dime sized hail reported at Possum Kingdom Reservoir.
-
- Source: FTW/SVS NSSFC learned about this from a Severe Weather Statement
- (SVS) issued by the National Weather Service at Ft. Worth, TX (FTW).
-
- Initial start: The hail began at 32.73 degrees north, 98.33 degrees west.
-
-
- Had there been a weather watch, it would have been listed as either
- WT (tornado) or WS (severe thunderstorm) and followed by the box number.
-
- Here are some of the more common report abbreviations:
-
- *TORN Tornado (always has asterisk to catch your eye)
- A nnn Hailstones and diameter in inches. 475 would be 4 and 3/4 inches.
- WDMG Wind damage (usually has description of damage)
- G nnn Wind gust and speed in knots.
- TURB Turbulence (usually has altitude and severity of event)
- ----------------------------------------------------------------------------
- ----------------------------------------------------------------------------
- The tornado statistics are issued by NSSFC from once per month in the slow
- season to once per day when things are really cooking. Let's look at the
- headers (as I rewrite them):
-
- MONTH N U M B E R O F T O R N A D O E S
- ....1989.... ...1988... ..1987.. D E A T H S KILLERS
- PRELIM FINAL RUFF SMTH RUFF SMTH 86 NORM 89 88 87 86 NORM 89 NORM
-
- JAN 17 13 19 17 9 6 2 14 0 5 0 0 3 0 3
- FEB 27 18 1 4 23 19 37 20 0 0 6 2 6 0 0
- MAR 61 X 29 28 41 38 95 51 1 1 1 6 8 1 1
- . . . . . . . . . . . . . . .
- . . . . . . . . . . . . . . .
- . . . . . . . . . . . . . . .
- 298 31 806 701 805 656 961 780 3 32 59 15 88 2 18
- RUFF THRU MAY 6....298 VS 124 IN 1988 CURRENT 0732C MAY 7 1989
- SMOOTH THRU FEB.... 31 VS 21 IN 1988 VS 34 NORMAL...
-
- The statistics are broken down by month and contain data for the last four
- years and average data. In the 1989 columns under "NUMBER OF TORNADOES"
- there were 17 reported tornadoes in January (PRELIM). After removing any
- erroneous and duplicate reports this number dropped to only 13 under the
- FINAL category. The "X" in the FINAL category for March indicates that
- they have not completed sifting through the reports for that month yet.
- The 1988 and 1987 RUFF and SMTH (rough and smooth) colums function the
- same as the PRELIM/FINAL columns respectively. The "86" column represents
- the FINAL (or smoothed) number of tornadoes for 1986. The NORM column is
- the average (mean or "normal") number of tornadoes from about 1950 through
- present. The DEATHS columns are simply the number of people killed by
- month for the years 89 through 86 and the average killed (1950 - 1989) per
- month. The KILLERS columns represent killer tornado events for the
- current year and the average between 1950 and the current year (1989).
- A tornado is counted as a killer if one or more persons were killed.
- If 100 people were killed by a single tornado it would be counded as one
- killer event. Multiple killer tornadoes on the same day are counted as
- separate events. The last lines are the totals for the columns and a
- simplified re-cap. For example, there were 289 preliminary (RUFF)
- reports of tornadoes this year through May 6th, versus 124 for the same
- period in 1988 (interesting huh !). The same comparison is given for
- the FINAL (smooth) data but only for the period where complete data is
- available (in this case only through February). Although some reports
- are listed as FINAL, this does not mean these figures are cast in stone.
- Sometimes it's months or years until NSSFC receives reports of tornadoes.
- Consider tree damage in a deeply wooded national park. It might not be
- until some hikers discover the damage that a report is ever made.
-