Thursday, August 12, 2004

CHARGIN' CHARLEY IS TAKING AIM ON THE ENTIRE I-95 CORRIDOR

That's the best way to describe what will happen in the next 84 hours. If you live anywhere from Miami, Florida to Portland, Maine, you will be directly affected by this storm.

First, a couple major concerns:

1. Charley will be a Category 3 storm when it arrives on the Florida coast, and Tampa Bay is going to be toast. The low-lying area has exploded with development, and the harbor has been designes in a way that will maximize destruction. The storm surge is going to be 10-15 feet, with waves and wind on top of that. There will be hundred of millions of dollars in property damage in the Pinellas County-Tampa Bay area alone due to the massive home values there.

2. If Charley remains a hurricane as it crosses Florida, and is able to tap Atlantic moisture on it's way to the Carolinas, then the Chesapeake Bay is under the gun for moderate tidal flooding and 4-6 inches of rain, over the next 48 hours.

3. Our Isabel lesson taught us that the news grossly underestimated the extent of storm surge throughout the Chesapeake. Predictions were for 4-6 feet in the southern bay, and 2-4 feet in the Northern Bay. Observations from flooded areas in Dundalk and Baltimore and showed an 8 foot surge. The northern bay saw at least a 5 foot surge.

4. People will begin downplaying Charley once the winds decrease, but remember folks.. IT'S NOT THE WIND, IT'S THE WATER! With flooding rains in advance of Charley, plus the fact it is coming from the south, will enhance tidal and small river flooding as the surge moving UPSTREAM meets the runoff coming DOWNSTREAM. If you live anywhere within 100 feet of tidal waters, you should look around your house and determine what you would have to do if you had to move items to higher floors without much advance notice.

NOW THE FORECAST AND RELATED EFFECTS.

Friday AM: Charley re-emerges in SE Gulf and reaches Cat 3 status by noon. I predict winds will top at 125 mph with gusts to 150.

Saturday AM: By midnight Friday, landfall occurs in or just north of Tampa Bay area. Hurricane moves NNE through upper midsection of Florida on a line from Tampa to Orlando to Jacksonville to just west of Savannah Georgia. Damage will be nearly catastrophic along the coast, and extensive to severe from Tampa northeastward to Orlando. Winds will decrease to 75 mph within 6 hours of crossing the coast, but gusts to near 100 mph will remain to Jacksonville.

Due to interaction with cold front moving east, Charley will accelerate to a forward motion of 30-40 mph. Although the storm wind strength will decay once inland, Charley may maintain tropical characteristics and thus Tropical Storm status to the border of South/North Carolina.

If sustained winds in the Chesapeake Bay exceed 30 mph, the Route 301 bridge will be closed.

Saturday night: Urban areas along I-95 from Atlanta, GA to Baltimore, MD may experience wind gusts anywhere from 30-70 mph, especially when the remnants of the storm pass overhead. Charley will be downgraded to a Tropical Depression by 8 PM as it approaches the Chesapeake Bay. However, with access to the Atlantic, and the encroaching cold front, areas from Raleigh-Durham to New York City will be under threat of tornadoes due to the 'shear' caused by the influx of tropical moisture being forced upward by the front. And due to the southwest angle of this storm, it will produce a surge in the bay ranging from 2-4 feet in the southern bay to 3-6 feet in the northern bay. The surge is higher farther north due to the channeling effect, as the fetch of the wind over open water will allow for water to build up as the storm pushes north.

Sunday: Skies will rapidly clear from PA on south once the storm passes, and hopefully it will take the cold front with it. From New York on north, there will be tremendous amounts of rain, enhanced by the storm accessing moisture from the Atlantic. Inland flooding will be significant, and NWS is projecting rainfall totals near 7 inches in upstate New York and mountainous areas of New England. Flood Warnings are already posted for much of Vermont.

A SUMMARY OF WATCHES AND WARNINGS YOU CAN EXPECT...

On Friday
Hurricane Warnings will be posted for the northeast coast of Florida. Tropical Storm Warnings will extended on the west side all the way to near Tallahassee.

Tropical Storm Warning (winds 39-73 mph possible within 12-24 hours) will be posted from Beach, SC to Norfolk, VA.

Tropical Storm Watches (winds 39-73 mph possible within 24-36 hours) will be posted from Norfolk, VA for the entire Chesapeake Bay and up to Cape Henlopen, DE.

On Saturday
Tropical Storm Watches in those areas will be changed to Warnings. Flood Warnings will cover much of the NE Corridor from NYC to Philly, down the Del-Mar-Va to Richmond. Tornado Watches and Warnings will be the norm for the entire I-95 corridor from Raleigh to NYC.

IN CONCLUSION...

This is an extremely dangerous storm that has the potential to eclipse Donna in 1960 AND Andrew in 1992 as the most destructive storm to strike Florida. The region in Florida targeted by Charley is one of the most developed and expensive in the state. Damage will be in the billions of dollars. Though Andrew was a Cat 5 at landfall, it did not strike a densely populated area. What Charley may do is the equivalent of what would have happened were Isabel to make a direct hit on Miami.

The major cities and their surrounding suburbs will experience significant flooding due to pre-storm ground saturation and strained drainage systems from prior flooding this summer. Due to the combined effects of heavy upstream rain and downstream tidal surges will create extensive mainstem river flooding.

For the DC-PHL area, this storm will not be as severe as Isabel, however it will deliver the torrential rainfall that we expected to get in that hurricane. Do not underestimate the damage that can be caused by 4-6 inches of rain in a 24-36 hour period. A saturated ground will destabilize old trees, and wind gusts approaching 50 mph could easily topple trees and branches, causing scattered power outages.

You should take some time to secure loose items in your yards and properties. Materials that are not or cannot be tied down should be taken inside, such as trash cans, grills, umbrellas, plants, etc. If you live near a small stream or tributary, or low-lying area, it would be wise to protect or waterproof any valuables in your basement if you are prone to flooding.

Above all... stay calm, be prudent, don't panic and keep checking Foot's Forecast so you can stay ahead of the storm.

The next update will be Friday morning.

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