Widespread precipitation is expected across the Northwest and northern Rockies through Monday, including heavy mountain snow for parts of the region. A powerful storm is expected to bring periods of heavy rain, gusty winds, and the potential for severe thunderstorms throughout the southern to central Plains between tonight and Monday. Read More >
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Wilma was a classic October hurricane which struck South Florida as a Category 3 hurricane on October 24th, 2005. Wilma developed from a tropical depression near Jamaica, a typical source region for October tropical cyclones, on the afternoon of October 15, 2005. It became the 21st named storm of the season during the morning hours of October 17, 2005, which tied the record for the most named storms in one season originally set back in 1933. Wilma underwent a rapid intensification cycle which began on October 18th and ended in the early morning hours of October 19th, with a central pressure decrease of an incredible 88 mb in only 12 hours! The central pressure reached 882 mb, making Wilma the most intense hurricane ever in the Atlantic Basin, a full 6 mb lower than Hurricane Gilbert in September 1988. Figure 1 (left) illustrates a satellite picture of Wilma shortly after its time of peak intensity. Wilma went on to make landfall on Cozumel Island just off the Yucatan Peninsula as a strong category 4 hurricane on Friday, October 21st, then drifted erratically over the Yucatan Peninsula through Saturday evening October 22nd. Wilma began to move off the northeast coast of the Yucatan Peninsula on the night of the 22nd, then gradually accelerated northeast over the southern Gulf of Mexico toward South Florida as a strong mid and upper-level trough over the central United States moved south and forced a southwesterly steering flow. The hurricane made landfall as a category 3 storm shortly before 7 AM Monday, October 24th on the southwest Florida coast between Everglades City and Cape Romano. Figure 2 shows an infrared satellite image, while Figures 3 and 4 illustrate radar reflectivity and velocity images/loops of Wilma while crossing the peninsula. Figure 5 illustrates Wilma's track across South Florida. Wilma exhibited a very large 55 to 65 mile-wide eye while crossing the state, and the eye covered large portions of South Florida, including the eastern two-thirds of Collier County, extreme northwestern Miami-Dade County, the southern and eastern third of Hendry County, most of Broward County, and all of Palm Beach County. The eye also clipped the southeastern shore of Lake Okeechobee. The eye wall, the part of the storm with the strongest winds, affected virtually all of South Florida. Around 10:30 AM, a South Florida Water Management District (SFWMD) meteorological station located at the south end of Lake Okeechobee reported sustained winds of 103 mph. Sustained hurricane force winds (74 mph or greater) were observed over all areas except Hendry and Glades counties, and even those two counties measured hurricane force gusts. The highest recorded gusts were in the 100-120 mph range. An interesting and revealing aspect of Wilma was the wind field in the eye wall. The winds on the back (south/west) side of the eye wall were as strong, if not stronger, than those on the front (north/east) side. This goes against the common, but sometimes erroneous, belief that the strongest winds in a hurricane are always in the right-front quadrant of the storm. This occurred over much of South Florida, except for central and southern Miami-Dade County which barely missed the southwestern portion of the eye wall, and likely contributed to the heavier damage across Broward and Palm Beach counties compared to slightly lesser damage across much of Miami-Dade and Collier counties. The following are some preliminary maximum sustained winds and peak gusts observed across South Florida:
** This measurement is taken at 145 feet while the traditional representative measurement of a surface wind is taken at 30 feet from the ground. *** Data from the South Florida Water Management District. Figure 7 shows that the lowest pressure recorded at NWS Miami while the storm center passed to the north was around 966 mb. Wilma moved rapidly northeast across the state, with an average forward speed of 25 mph. Wilma exited the east coast over northeastern Palm Beach County near Palm Beach Gardens around 11 AM Monday October 24th as a Category 2 hurricane with maximum sustained winds of around 105 mph. It traversed the southern peninsula in about 4 hours. Rainfall amounts across South Florida generally ranged from 2 to 4 inches across southern sections of the peninsula to 4 to 6 inches across western Collier county and around Lake Okeechobee, with isolated amounts of up to 6 to 8 inches observed (see Figure 8). The maximum storm surge across the area was mostly south of Chokoloskee in Mainland Monroe county where a storm surge of 13 to 18 feet was forecast. Figure 9 illustrates a simulation of the storm surge for hurricane Wilma. Chokoloskee experienced a storm surge of around 7 feet, which caused extensive flooding. A storm surge of around 7 feet was estimated in Marco Island, with 4 feet in Everglades City. The southeast coast didn't escape the effects of the storm surge, with the tide gauge in Virginia Key reported a maximum surge of around 4 feet. Minor surge flooding was noted in Coconut Grove, Downtown Miami, and Northeast Miami. Damage was widespread, with large trees and power lines down virtually everywhere, causing over 3 million customers to lose power. Structural damage was heaviest in Broward and Palm Beach counties where roof damage and downed or split power poles were noted in some areas. High-rise buildings suffered considerable damage, mainly in the form of broken windows. This was observed mainly along the southeast metro areas, but also in Naples, which underscores the higher wind speeds with height commonly observed in hurricanes. One confirmed tornado was observed in rural Collier County around 2:30 AM on the 24th, moving rapidly northwest from the intersection of U.S. 41 and State Road 29 to the town of Copeland three miles to the north. An F1 intensity was assigned to the tornado as it caused snapped power poles, uprooted large trees, and significantly damaged mobile homes. Small swaths of greater damage elsewhere in South Florida have not been attributed to tornadoes, but were instead likely caused by "mini-swirls", small vortices within the eye wall that have been observed in previous strong hurricanes such as Hurricane Andrew in 1992. Additional Information  NOAA Survey ImagesLast updated on 10/30/2005. |
 Figure 1. Visible satellite pictures of Wilma shortly after its most intense point (left) from October 19, 2005 at 1:45 PM EDT (1745 UTC) and when approaching the Yucatan on October 21 at 1:45 PM EDT (1745 UTC) . View animation of Wilma while at its most intense point. Courtesy of the Univ. of Wisconsin.  Figure 2. Infrared satellite image of Hurricane Wilma crossing the South Florida coast from October 24 at 7:32 AM EDT (1132 UTC).  Figure 3. Radar reflectivity loop while Wilma was crossing South Florida from October 24 at 6:00 AM EDT (1000 UTC) to 9:00 AM EDT (1300 UTC). View Large High Res animation (caution 15MB file) or Low Res Animation (7MB file).  Figure 4. Radar velocity while Wilma was crossing South Florida from October 24 at 8:35 AM EDT (1235 UTC). View Large High Res animation (caution 6MB file) or Low Res Animation (4MB file).  Figure 5. Preliminary track showing the center of Hurricane Wilma as it moved across South Florida.  Figure 6. Wind gust recorder trace from WFO Miami showing peak wind during Hurricane Wilma (add 4 kt due to pen drag).  Figure 7. Barograph trace from the NWS Miami Forecast Office, showing lowest pressure of 966 mb.  Figure 8. NWS Miami radar (KAMX) storm total precipitation estimate from 10:40 PM EDT Sun October 23 to 10 AM EDT Mon October 24.  Figure 9. NHC/TPC storm surge simulation for Wilma across portions of South Florida in feet. Notice highest surge south of Chokoloskee to Cape Sable Area. |
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