http://www.hpc.ncep.noaa.gov/tropical/
Gilbert:
http://www.hpc.ncep.noaa.gov/tropical/rain/gilbert1988.html
Isidore:
http://www.hpc.ncep.noaa.gov/tropical/rain/isidore2002.html
Hurricane Gilbert – September 14-21, 1988
On September 3rd, a westward moving tropical wave showing no signs of organization emerged
off the northwest African coast into the North Atlantic. Over the next several days, a broad area
of low pressure formed whose circulation extended nearly to the equator. An organized center
was not evident until it approached the Windward Islands on the 8th. By the 9th, it had developed
into the 12th tropical depression of the season 400 miles east of Barbados.
The depression moved west-northwest at 17 mph, reaching tropical storm strength over the
Lesser Antilles on the afternoon of the 9th. Rapid strengthening ensued on the 10th, bringing
Gilbert to hurricane-force that evening. The system continued its trek west-northwest, passing
over Jamaica as a major hurricane on the 12th. After it emerged into the northwest Caribbean
Sea, Gilbert rapidly intensified into a category 5 hurricane, with recon reports ranging between
882-885 hPa for the hurricane’s surface pressure on the afternoon of the 13th. It moved into the
Yucatan peninsula, becoming the first category 5 hurricane to make landfall in the Atlantic Basin
since Camille in 1969.
Gilbert tracked west-northwest through the Gulf of Mexico as a category 3 hurricane, making its
final landfall in northeast Mexico just north of La Pesca on the afternoon of the 16th. As the
weakening system moved across Texas and Oklahoma, heavy rains fell along its path, as it
accelerated northeast thru the Mid-Mississippi Valley into the Great Lakes late on the 19th/
early on the 20th. Below is the track of this cyclone, provided by the National Hurricane
Center.
The graphics below show the storm total rainfall for Gilbert. Note the maxima along and just to the left/west
of the track of the cyclone.
Tropical Storm Isidore – September 20-29, 2002
A tropical wave moved off the coast of Africa on 9 September accompanied by a large area of
thunderstorms. The convective activity decreased significantly as the system moved toward the
west-southwest during the next few days. As the wave approached 50 West, the shower activity
began to increase and an upper-level anticyclone became evident over the system. Shortly after
noon on the 14th, there was enough convection and rotation to classify the system as a tropical
depression as it approached Trinidad and the northern coast of Venezuela. The depression moved
west-northwestward and its development was halted by its interaction with land. Around noon on
the 15th, the system had degenerated into a tropical wave in the eastern Caribbean Sea. However, as
the wave entered the western Caribbean Sea, it redeveloped a closed circulation and regained tropical
depression status on the morning of the 17th, about 120 n mi south of Kingston, Jamaica.
It strengthened into Tropical Storm Isidore after midnight on the 18th, and, embedded within a weak
steering current, the tropical cyclone moved very slowly toward the northwest, passing just west of
Jamaica. Isidore then moved very slowly toward the west-northwest across the Cayman Islands and
became a hurricane shortly after noon on the 19th. Its winds reached 105 mph after midnight on the 20th
as it was nearing the southwest coast of the Isle of Youth, Cuba. Although the minimum pressure
continued to drop, Isidore’s winds decreased a little bit and the hurricane made landfall near Cabo Frances
in western Cuba during the afternoon of the 20th. The hurricane then moved west and southwestward
toward the Yucatan Peninsula and restrengthened, reaching its maximum intensity of 125 mph after
noon on the 21st.
Isidore meandered for 24 to 36 hours over northern Yucatan and weakened to a minimal tropical storm. It
finally moved northward over the Gulf of Mexico where the circulation expanded but the cyclone never
redeveloped an inner core of strong winds due to its extremely warm core. Isidore made landfall with winds
of 65 mph just west of Grand Isle, Louisiana at 0600 UTC 26 September. Once it moved inland, Isidore
weakened to a tropical depression and moved north-northeastward across the southeastern United
States, producing torrential rains. It became an extratropical storm over southwestern Pennsylvania at
1800 UTC 27 September, and was then absorbed into a frontal zone. Below is the track of Isidore,
furnished by the National Hurricane Center.
The storm total rainfall maps below were constructed using data from the National Climatic Data Center,
the Louisiana Agriclimatic Network, the Southwest Florida Water Management District, and the
Comision Nacional del Agua, parent agency of Mexico’s National Weather Service.