TRMM SEES WILMA OVER THE YUCATAN PENINSULA MOVING THROUGH FLORIDA

Link to image of WILMA rain October 2005

See LARGE [.3 mb] QUICKTIME ANIMATION of rain accumulation See SMALLER [.3 mb] QUICKTIME ANIMATION of rain accumulation See MEDIUM [.5 mb] MPEG ANIMATION of rain accumulation

POWERFUL HURRICANE WILMA POUNDS THE YUCATAN, RAKES FLORIDA After setting the all time record for the lowest recorded pressure in the Atlantic basin as a powerful Category 5 hurricane in the western Caribbean, Hurricane Wilma weakened to a still powerful Category 4 storm and slowly took aim at Cozumel and the Yucatan Peninsula. On the 21st of October 2005, Wilma slowly crossed over Cozumel as a strong Category 4 hurricane with sustained winds reported at up to 125 knots (144 mph) by the National Hurricane Center (NHC). The center of Wilma then slowly drifted over the far northeastern tip of the Yucatan Peninsula delivering torrential rains and strong winds.

The Tropical Rainfall Measuring Mission (TRMM) satellite has been monitoring the progress of this powerful storm. With its array of sensors, TRMM provides unique images and information on tropical cyclones over the global Tropics. This first image was taken by TRMM when Hurricane Wilma was right over the far northeastern tip of the Yucatan Peninsula. The image was taken at 16:31 UTC (12:31 pm EDT) 22 October 2005 and shows the horizontal distribution of the rain intensity inside of Wilma as detected by TRMM's sensors. Rain rates in the central portion of the swath are from the TRMM Precipitation Radar (PR), the only radar capable of measuring precipitation from space. The PR is also able to provide fine resolution rainfall data and details on the storm's vertical structure. Rain rates in the outer swath are from the TRMM Microwave Imager (TMI). The rain rates are overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS). Mature, intense tropical cyclones often undergo what is known as eye-wall replacement cycles wherein a concentric outer eyewall forms outside of the original one and eventually contracts and replaces the inner eye. In this image, TRMM reveals that Wilma has a fairly well-defined, outer eyewall (ring of moderate intenstiy rain [green ring] with embedded areas of heavy rain [red arc]) surrounding the remnants of an inner eye (faint green ring).

This double eyewall structure is also evident in the image on the right, a 3D isosurface courtesy of the TRMM PR that was contructed from the same overpass as the previous image. The vertical height of the isosurface (15 dBZ) is determined by the height of the precipitation-sized particles within the storm as detected by the TRMM PR. The outer eyewall is clearly visible by the ring of higher echo tops (red ring). The older but separate inner eye is still visible (small area of faint red tops) in the center of Wilma. At the time of these images, Wilma was a Category 3 hurricane with maximum sustained winds reported at 100 knots (115 mph) by NHC.
VERY LARGE [65.6 mb] OCTOBER 22, 2005 3-D 15 dbz isosurface Precipitation Radar QUICKTIME animation
LARGE [8.9 mb] OCTOBER 22, 2005 3-D 15 dbz isosurface Precipitation Radar QUICKTIME animation
SMALL [1.5 mb] OCTOBER 22, 2005 3-D 15 dbz isosurface Precipitation Radar MPEG animation

Before being caught up in the westerlies, Wilma practically stalled out over the Yucatan, resulting in a sustained period of heavy rain and flooding. The TRMM-based, near-real time Multi-satellite Precipitation Analysis (MPA) at the NASA Goddard Space Flight Center provides estimates of rainfall over the global Tropics. MPA rainfall totals due solely to Wilma are shown in the center image at the top of this page for the period 17 to 25 October 2005 with storm symbols marking the storm track. Rainfall totals on the order of 12 to 16 inches (darker red areas) are located over the northeastern part of the Yucatan Peninsula.

After drifting over the Yucatan and weakening to a Category 2 storm, Wilma was picked up by a midlatitude trough. This caused the storm to accelerate off to the northeast across the southeastern Gulf of Mexico towards Florida where it made landfall on the morning of 24 October just south of Marco Island. Wilma raced across southern Florida with 100 plus mph winds in just 6 hours. This helped to keep rainfall totals down. MPA rainfall amounts over Florida are generally 6 inches or less (green areas).

Defying the odds, Wilma regained strength, becoming a Category 3 storm with 125 mph sustained winds, before impacting the west coast of Florida and later restrengthening yet again back to a Category 3 storm after re-emerging over open water in the Atlantic. The image on the right at the top of this page was taken by TRMM at 21:15 UTC (5:15 pm EDT) 24 October 2005 soon after Wilma had crossed Florida.

Both the horizontal rain intensity pattern and the corresponding 3D isosurface image to the right (view is to the south) show that Wilma now has a single, very large eye. At the time of these images, Wilma was a Category 3 storm with sustained winds of 105 knots (121 mph). Wilma would continue to move quickly off to the northeast paralleling the East Coast as a result of being drawn into an advancing strong midlatitude low pressure system. Wilma was responsible for 11 deaths in Haiti, 1 in Jamaica, 12 in Mexico and 6 across Florida