National Weather Service Forecast Office Miami-South Florida

National Weather Service
South Florida Forecast Office
Miami, Florida

View the Post Hurricane Report issued by NWS Miami
Summary

Hurricane Frances made landfall around midnight Saturday night in Martin County, Florida. The infrared satellite image from 11:40 pm on Saturday September 4th provided a snapshot of the hurricane as the western portion of the eyewall was passing over northeastern Palm Beach county, and counties to the north (Fig. 1).

Figure 1. Satellite image from 4 September 2004 at 11:40 pm. The center of Hurricane Frances was located approximately 19 miles east-southeast of Stuart, Florida. Click on image to view larger version.

The hurricane continued on a path just north of Lake Okeechobee by 5:00 AM EDT Sunday and ultimately moved northwest across Okeechobee County (Fig. 2). Hurricane Warnings were in effect for the entire east coast of Florida from Fernandina Beach to south of Florida City, including metro Palm Beach, Broward, and Miami-Dade counties as well as Lake Okeechobee.

Figure 2. Preliminary track showing the center of Hurricane Frances as it moved across the Florida Peninsula.

Rainfall and Radar Observations

The animation of radar images below provides another perspective from which to view the hurricane's path across southern and central Florida (Fig. 3). The eyewall associated with Frances was very large and slow moving, producing copious amounts of rainfall over the locations it crossed. At Palm Beach International Airport, the official NWS observing site measured 13.00 inches of rain from the event. Much less rainfall occured across the rest of South Florida, with most sites reporting rainfall between 2 and 5 inches. Some selected observations from South Florida included 5.55 inches at Devils Garden (in Glades County), 4.85 inches at North Perry/Hollywood Airport (in Broward County), and 3.77 inches at North Miami Beach (in Miami-Dade county). Much lesser amounts occured to the south and west. Naples Regional Airport (in Collier County) reported only 1.06 inches of rainfall while Flamingo Ranger Station (in Monroe County) measured 2.08 inches.

Figure 3. NWS Miami radar animation from Sept 4th and 5th. Click on image for longer animation. (caution: file is large)

Wind Observations

The strongest winds from Hurricane Frances in South Florida were experienced in Palm Beach County and on Lake Okeechobee. The maximum sustained wind at the Palm Beach International Airport was 64 mph at 12:56 AM Sunday morning, and the highest gust of 82 mph occurred at 1:44AM EDT. The strongest measured winds in Palm Beach County were recorded in Jupiter, where the police department measured winds sustained to 80 and gusting to 90 mph a 1-1/2 miles from the coast. On Lake Okeechobee, maximum sustained wind was at the U.S. Army Corps of Engineers Port Mayaca observing site. This location recorded sustained winds of 74 knots (85 mph) at 0500 UTC (1:00 am EDT) early on Sunday morning. Other locations on the Lake recorded winds sustained from 45-55 knots (52-63 mph). The maximum gust measured was 81 knots at a South Florida Water Management buoy on the northern part of Lake Okeechobee.

Lake Okeechobee Water Levels

The storm surge generated by Frances as she passed north of Lake Okeechobee was about 5 feet. This was indicated by the U.S. Army Corp of Engineers data platforms on the lake.

Lake Okeechobee water level at selected sites

Figure 4. Water level readings from the U.S Army Corps of Engineers sites on Lake Okeechobee.

All data contained within this report is considered preliminary and subject to revision. More information will be added to this summary as it becomes available.