TIME: Almanac 1993/TIME Almanac 1993.iso/time/charts/envi/wx92.004

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                                                                                The WEATHER of 1992

Highlights: Eastern Pacific Hurricanes

Weatherwise Magazine - February-March  1993

By Edward N. Rappaport and Miles B. Lawrence


  [EDWARD N. RAPPAPORT and MILES B. LAWRENCE are meteorologists
at the National Hurricane Center, National Weather Service, in
Coral Gables, Florida.]


   The 1992 hurricane season in the eastern North Pacific Ocean
was record breaking in more ways than one. The 24 named storms
broke a record of 22 set in 1985, and the 27 tropical cyclones
broke a record of 26 set in 1982.

   The year's total of 14 hurricanes was two shy of the record
set in 1990 but easily greater than the seasonal average of 10
(calculated since 1966, when routine weather satellite
surveillance began). And eight of the hurricanes were Category 3
or stronger on the Saffir-Simpson scale.

   One hurricane, Tina, lasted 24 days -- longer than any other
North Pacific tropical cyclone on record. (Typhoon Rita lasted 22
days in 1972.) Tina was also the region's most powerful hurricane
this year, with maximum one-minute winds estimated at 150 m.p.h.

   Tropical cyclones originating in the eastern North Pacific
Ocean killed six people in Mexico, and five others were reported
missing near the country's southwestern coast. In addition, an
eastern North Pacific tropical depression entered the central
Pacific hurricane basin and became Hurricane Iniki. Iniki killed
three people in Hawaii, and two others were reported missing.

   The following are summaries of storms affecting land:

Hurricane Darby

   Darby formed from a westbound tropical wave that emerged from
the northwestern coast of Africa on June 19. The wave did not
develop before appearing over the eastern Pacific on June 29, but
cloud organization gradually improved and the system strengthened
into a tropical depression on July 2. A day later, it became
Tropical Storm Darby.

   Although the storm was centered nearly 350 miles south-
southeast of Acapulco, the Mexican resort city got Darby's
heaviest 24-hour rainfall total: 5.75 inches on the 3rd. Three
people died in the resulting floods, according to the newspaper,
Excelsior. In addition, four fishermen were reported missing and
180 small shops were damaged.

   Darby first moved west-southwest at about 10 m.p.h. The storm
turned west-northwest, then northwest, and accelerated to about
20 m.p.h. July 4-7. (Storms in this area average about 12 m.p.h.)
Upper-level outflow became more distinct, and the circulation
expanded. Darby reached hurricane status on the evening of the
4th. Darby's outer bands spread rain as far north as Puerto
Vallarta on the 4th.

   The hurricane passed just south of Isla Socorro on the 5th.
The Mexican Weather Service at Socorro observed a minimum
pressure of 974.5 mb and they estimated sustained wind at 105-115
m.p.h., with gusts to about 125 m.p.h.

   Satellite imagery on the night of July 5-6 showed the eye
gaining definition after it passed Socorro, with an estimated
minimum pressure of 968 mb and a maximum sustained wind of 120
m.p.h. Although Darby began to weaken over cooler water, it
maintained hurricane strength farther north (about 24 degrees N
latitude) than any previous July storm in the eastern Pacific.

   Darby weakened to a tropical depression on the 8th, turned
north under the influence of low-level steering currents, and
lost tropical characteristics on the 9th. The following week,
Darby and its remnants spread rain as far north as central
California and as far east as the Central states. Although 24-
hour rain totals were generally less than 0.5 inch, several
southern California stations broke daily records. In addition,
seven-foot waves lashed south-facing beaches of southern
California.

Hurricane Lester

   Like Darby, Lester was a westbound tropical wave, becoming a
tropical depression on August 20 about 275 miles south-southwest
of Manzanillo, Mexico. Later the same day, it strengthened into a
tropical storm. Two ships reported a sustained wind of
approximately 45 m.p.h. about 200 miles from the center, which
crossed Isla Socorro. On August 22, Lester developed a banding-
type eye and remained a hurricane for about half a day.

   A major trough approached the U.S. West Coast on the 22nd and
became quasi-stationary there. The steering flow carried Lester
north then northeast to a landfall near Punta Abrejos early on
the 23rd. After crossing Baja California and the Gulf of
California as a tropical storm, Lester hit land again near Isla
Tiburon, Mexico, around midday. Lester produced heavy rainfall
over northwestern Mexico, with Presa Rodriguez, Sonora, reporting
the largest total, 8.66 inches. Although no deaths have been
reported, the cyclone left more than 5,000 people homeless.
Several small communities were destroyed west of Hermosillo and
along the highway to San Diego.

   Lester probably was still barely a tropical storm as far north
as Tucson but dissipated rapidly over central New Mexico. The
storm caused minor flooding in California, Colorado, and Utah.

Hurricane Virgil

   Virgil was a small hurricane that made landfall on Mexico's
west coast midway between Lazaro Cardenas and Manzanillo. The
cyclone formed from a westbound tropical wave that caused a
distinct lower-tropospheric wind shift as it passed over Panama
on September 25. The deep convection increased but remained
unorganized until the wave neared 100 degrees W longitude on the
30th. A curved-band pattern formed and the system eventually
became a tropical storm on October 1.

   Weak vertical wind shear and a warm sea surface helped Virgil
intensify quickly. It became a hurricane on October 2, with a
distinct eye appearing on infrared satellite pictures. A ship
crew about 50 miles from Virgil's center reported a sustained
wind of 67 m.p.h.

   Virgil drifted northwest on the 2nd to about 275 miles south-
southeast of Manzanillo, but took a northward course when a
middle- to upper-level trough approached from the northwest. The
hurricane proceeded northwest again, however, and made landfall
near sunset on the 3rd, with an estimated 110-m.p.h. sustained
wind. Heavy rain drenched many locations: Presa La Villita,
Michoacan, reported the largest total, 10.02 inches.

   Because Virgil made landfall along a rather sparsely populated
section of the Mexican coast, the storm surge and wind probably
caused minimal casualties and damage. The Mexican government, as
well as Nacional and Excelsior, did report flooding and mud
slides, with one person missing in Colima and three people
injured in Guerrero. More than 1,000 homes were damaged in
Guerrero, Michoacan, and Colima. In Guerrero, 500 homes flooded
when the Atoyac River overflowed.

   Virgil weakened rapidly over mountainous terrain. By the time
the center of the cyclone passed just north of Manzanillo on the
4th, Virgil was losing tropical-storm strength. Virgil then moved
back over the Pacific with a small, weak low-level circulation.
Strong upper-level westerlies over the area prevented
regeneration.

Hurricane Winifred

   Winifred developed from a broad area of disturbed weather that
moved west-northwest from Panama on October 1, with its deep
convection slowly becoming more concentrated and better
organized. On October 6, the system developed into a tropical
depression about 450 miles south-southeast of Acapulco. Satellite
images showed increased convective banding the next day as the
depression became Tropical Storm Winifred. The cyclone gradually
turned to the northwest, with its forward speed decreasing from
about 17 m.p.h. to about 10 m.p.h.

   Winifred earned hurricane status on the 8th about 300 miles
from Manzanillo. Convective banding increased and an eye appeared
on satellite pictures. The hurricane reached a peak strength of
960 mb with a sustained wind of 115 m.p.h. on October 9. By then,
outer rainbands affected coastal areas of southwestern Mexico.

   Just prior to landfall, the steering flow associated with an
approaching upper-level trough turned the hurricane north-
northeast and increased Winifred's forward speed to about 15
m.p.h. The center of the hurricane came ashore 15 miles east-
southeast of Manzanillo during the afternoon of October 9. The
eye was not identifiable during the last few hours prior to
landfall, but the estimated minimum pressure was 975 mb with a
maximum sustained wind near 100 m.p.h. Gusts to about 110 m.p.h.
and a minimum pressure of 983 mb were observed at the Mexican
Meteorological Service office in Manzanillo near the time of
landfall.

   Three people reportedly died in flooding, as stations in
Colima and Michoacan reported four to six inches of rain on
October 9. Flooding was particularly extensive on the coastal
road south of Manzanillo. About 200,000 acres of farmland were
reportedly damaged. El Universal reported that the storm knocked
out power and water systems in parts of Colima. About 1,500
houses were damaged, as well as many hotels and restaurants. The
governor of Colima estimated damage at 16 billion pesos (more
than $5 million). Winifred weakened quickly over mountainous
terrain, dissipating on October 10.