Fierce storm hammers Southeast U.S.

The Southeast U.S. is under the gun today from a combination of severe thunderstorms, high winds, heavy rain, and coastal storm surge flooding. A tornado was reported on the ground near Eglin Air Force Base, Florida this morning, and tornado warnings have been posted for two separate squall lines moving through the Florida Panhandle and neighboring regions of Alabama and Georgia. These squall lines are expected to intensify and generate tornadoes, heavy rain, and strong winds as they push eastwards today. The Storm Prediction Center (SPC) has put most of Florida, Georgia, South Carolina, and North Carolina in their "Slight Risk" category for severe weather today, warning of the possibility of supercell thunderstorms capable of spawning tornadoes. If the air mass in front of these squall lines becomes sufficiently unstable this afternoon due to solar heating of the lower atmosphere and other factors, SPC may need to upgrade their severe weather category to "Moderate Risk", the second highest level of risk.


Figure 1. Satellite image of the December 2 storm. Image credit: NASA/GSFC.

The storm's powerful winds blowing over the Gulf of Mexico have created storm surges of 2 - 3 feet along the coast, from New Orleans to the Florida Panhandle. A storm surge of two feet was recorded in Waveland, Mississippi last night and this morning, which caused flooding of low-lying roads in Hancock County. New Orleans recorded 2.42" of rain yesterday from the storm, breaking their record for the rainiest December 1. Radar-estimated rainfall (Figure 2) shows up to five inches of rain has fallen over some regions of the Florida Panhandle, and additional rainfall amounts of 2 - 5 inches are expected along the track of the storm as it heads north-northeast today. Flash flooding was reported in Charleston, SC this morning, closing several roads.


Figure 2. Radar-estimated rainfall from the December 2 Gulf Coast storm.

Also receiving a pounding from the storm were the Gulf Coast beaches from Dauphin Island, Alabama, to the Florida Panhandle near Pensacola. A storm surge of two feet, topped by battering waves 10 - 12 feet high, probably caused millions of dollars of erosion damage last night and this morning. A 16-mile stretch of man-made beach encompassing the Alabama coastal communities of Gulf Shores and Orange Beach suffered $5 million in erosion damage from the pounding delivered by Tropical Storm Ida last month. The two beach communities, along with Gulf State Park, spent about $24.2 million in 2005 to strengthen 16 miles of shoreline by dredging about 6 million cubic yards of sand from the sea floor and dumping it on shore. Hurricanes Gustav and Ike in 2008 did about $9.5 million in erosion damage to the Gulf Shores beach. Because the beach is man-made, the Federal Emergency Management Agency and the Alabama Emergency Management Agency treated it as they do bridges and highways, paying 85 percent of the tab to repair storm damage.

You can follow today's severe weather outbreak with our Severe Weather and Tornado pages.

Second Annual Portlight Honor Walk this weekend
When:
Saturday, December 5, 2009 or Sunday, December 6, 2009

What:
A nationwide grassroots event to raise funds for and awareness of Portlight's ongoing efforts specifically aimed at providing Christmas presents for kids and families devastated by the recent Atlanta floods, South Carolina wildfires, American Samoa tsunami, and other disasters that may occur.

Why:
Un-served, underserved and forgotten people are depending on us.

How:
We need one hundred people across the country to commit to walking one mile on this day, and to raise at least $300.00 in sponsorship from friends, family, co-workers, neighbors, etc. Participants can choose where to walk--it can be the park, the mall the neighborhood--anywhere you choose. The first 100 participants to raise at least $300 will receive a commemorative T-Shirt.

To register, simply e-mail your intention to participate at paul@portlight.org

Check the Portlight featured Weather Underground Blog regularly for updates!

The Honor Walk Sponsor Form available here will help you keep track of funds and pledges:
http://www.portlight.org/images/walkerform.pdf

Next post
The embattled director of the Climate Research Unit (CRU) of the UK's University of East Anglia announced that he will be temporarily standing aside as director until an independent review resulting from allegations following the publication of emails illegally hacked from his computers. I'll be posting a response tonight or Thursday morning, assuming that today's storm does not generate a deadly tornado outbreak. I'm also working on a post titled, "Don't Shoot the Messenger", in response to charges by the Wall Street Journal in an editorial yesterday that climate scientists have a vested interest in promoting alarmist views of the climate in order to get research funding.

Jeff Masters