Hurricane Frances

Pre-Landfall 3 | Summary
Posting Date: September 2, 2004, 1:00:00 PM

Please note that, as of this posting, CATRADER and CLASIC/2 clients can download probability-weighted events sets. While the five scenarios posted on the Scenarios page of this web site are representative of the range simulated by the AIR model, we strongly recommend running the full event set in your software. Also note that the range of loss estimates provided in this posting is quite large, reflecting the considerable uncertainty that exists with respect to the future track and intensity of Hurricane Frances. As the storm approaches the U.S. coast, this uncertainty will diminish and the range of losses will also narrow as a result. Despite a modest increase in minimum central pressure since this morning, Hurricane Frances remains a Category 4 hurricane, with maximum sustained winds now near 140 mph. As of 5:00 p.m. EDT on Thursday, September 2 Frances is centered very near the island of San Salvador and about 375 miles east-southeast of the Florida east coast. Frances is now moving on a northwest course at around 10 mph. The National Hurricane Center (NHC) forecasts it to continue on a northwest to west-northwest motion, though some “wobbling” may occur over the next 24 hours. Francis remains a large system, with hurricane force winds extending outward to 80 miles from the center, and tropical storm force winds extend to 185 miles. The NHC projects some fluctuations in intensity over the next 24 hours but the forecast still indicates that Frances will reach the Florida coast as a Category 4 storm. Frances remains well-organized and satellite images show a distinct eye. A Florida landfall is expected on the Florida east coast sometime on Saturday. Because Frances has such a large windfield, tropical storm force winds are expected to reach the coast much earlier than the eye of the storm. A hurricane warning has been issued for the east coast of Florida from Florida City north to Flagler Beach. Emergency officials in Florida have ordered mandatory evacuations for 10 counties for residents in mobile homes and low-lying areas. Similar orders may soon be issued for an additional nine counties. The AIR tropical cyclone modeling team has run hundreds of scenarios representing a variety of assumptions about the storm’s future track and intensity. Five of these are now posted on the scenarios page of this website, where CATRADER® and CLASIC/2™ clients can view wind speed and loss maps. Note that these five scenarios show potential landfall locations going from south to north along the Florida coast. As the landfall locations go from south to north, the losses decrease as a result of decreases in population and exposed properties. In addition, probability-weighted event sets representing the full range of simulated scenarios are now available for download. Note that the loss estimates provided in this posting are for the U.S. only. The mean loss, which is near the 70th percentile of the distribution, is significantly larger than the median loss. This is because there are very large loss-producing scenarios characterized by high intensity (wind speeds) and landfall locations in densely populated areas. The AIR tropical cyclone modeling team continues to monitor Hurricane Frances closely. As always, it is important to emphasize that there is considerable uncertainty surrounding the future track and intensity of this storm. Hurricane Charley was a striking reminder that major storm systems can change their character very rapidly, even within hours of landfall. AIR will post additional information and loss estimates for Hurricane Frances tomorrow.

Pre-Landfall 3 | Downloads
Posting Date: September 2, 2004, 1:00:00 PM