Monday, September 6, 2004

According to insurers in a report



By the time you read this, Frances will be churning through Georgia on her way northeast to the Carolinas, Tennesse and West Virginia, dropping lots of tornadoes along the way. However, with the approach of a cold front from the Midwest, I think Frances is showing signs of making an earlier turn toward the north and northeast. This may end up sinking the original thoughts of Tropical Storm Jeanne forming off the Mid-Atlantic coast.

For those who need a snapshot of the forecast for I-95 corridor of VA-MD-PA (my usual customers):

TUE: Cloudy early with rain showers developing from southwest to northeast. Brisk easterly winds will bring tides 1-2 feet above normal. By nightfall, widespread rain over the entire northeast.

WED: A prolonged rain event for just about the entire day for everyone from Richmond to New York City. I would expect rain amounts around an inch east of the mountains, and possibly 3-6" in some areas of the Appalachians, with localized amounts near 10"

THU: The remnants of Frances move north of us, and a cold front slides east, so it all goes out with a bang and some thunderstorms

The scenario I see for the remnants of Frances is this:

(1) With a large high off the coast feeding Atlantic moisture in from the east, this could make for a significant flooding situation from the Carolinas all through the Appalachians and into New York state. The moisture feeding into Frances will slam up against the mountains,
enhancing the rainfall. It may be a similar situation to Hurricane Juan in 1985, where rainfall in the Appalachians exceeded that which fell near landfall. This is a NWS rainfall estimate over the next 5 days.

(2) The high to the east and the cold front to the west will work in tandem to squeeze Frances as she moves northeast. And saturated grounds ahead of the storm’s path actually serve to lessen the frictional effect of the storm against the land, negating any potential weakening as we saw in the Gaston disaster.

(3) What we may end up with is a not-so-weakened Frances as one would expect, still maintaining tropical characteristics as it moves from the Florida panhandle to Atlanta to eastern Tennessee and West Virginia. The eventual destination is central Pennsylvania, where she may finally become absorbed by the cold front. The whole time, like it or not, believe it or not, the high is providing a constant source of moisture direct from the Atlantic to feed the storm on it’s northward march. So we may see the cloud base expand from Frances, not shrink.

(4) The combined effect of the high to the north and the low to the south will continue to produce the tight wind gradient you have seen advertised on the news the past 2 days. This will enhance the heavy surf along the coast to the point that gale warnings may be posted from Mrytle Beach, SC probably to New York City. The result will be considerable beach erosion and lead to a very unpleasant end of the summer vacation period for many, as well as a dismal start to the school year.

Needless to say, coastal and inland residents from South Carolina all the way to New York should keep a close eye on what may become a rapidly changing forecast over the next several days.

View the eastern satellite for evidence of this arrangement. Now that I analyze this closer, I can see that the buildup of clouds and thunderstorms off the Carolina coast may be creating that channel through which Frances can move. The result of that area of disturbed weather creates “pressure falls” which is where the atmosphere pressure begins to decline in advance of a storm, enabling the storm to more easily move through that particular area.

So when we once thought the East coast would be spared the direct effects of this storm, it now appears that we still have a long way to go before we are finished with Frances.

AND THEN THERE’S IVAN (the terrible)

I believe it is rude and irresponsible of the press to be hyping the approach of Ivan so quickly after the departure of Frances. The NHC will tell you time and time again that beyond 3 days, the projected track can change as much as 200 miles and the projected strength can be off as much as 30 mph. View the latest computer models to see that there is lots of variability in the track beyond 3 days.

FIRST, THE GOOD NEWS regarding the outcome of Ivan:

(1) If the storm gets hung up over the mountains of Hispanola and or Cuba, this will significantly disrupt the storm re-emerging in the Keys or Bahamas. And if the storm were to approach the Bahamas, it’s efforts to re-organize would again be disrupted because those islands are so spread out and irregular. This was the saving grace for Florida with Frances. The slow motion of that storm caused the land surfaces to disrupt the eye, and it took several days for the storm to re-organize, but never did re-intensify.

(2) Steering currents seem to want to march Ivan into the Gulf one way or another. This would be good news for Florida and the East coast, but bad news for anywhere from New Orleans westward to Galveston.

NOW, THE BAD NEWS regarding the outcome of Ivan:

(1) This hurricane went from Category 1 to 3 in one day, and seems to be making a run for Cat 5 before it even nears Hispanola. The stronger it is earlier, the less power it will lose over land. It will probably be the strongest hurricane to enter the Caribbean since David in 1979, which you may remember pummeled Haiti, but never regained it's power and died out over the U.S.

(2) This is a very fast moving storm. Rarely do we see storms so far south move this fast, at last report 21 mph to the west-northwest. That is breakneck pace for a hurricane. That speed will reduce any weakening it may experience over Haiti or Cuba. The evidence of this is Hurricane Gilbert in 1988 which became the most powerful hurricane in the western hemisphere with a central pressure of 26.13 inches and winds at 200 mph. That mega-monster crossed Jamaica at 115 mph sustained winds over a 6 hour period and never lost an ounce of strength.

(3) The high that is currently blocking Frances is not projected to weaken and move east into the North Atlantic, but rebuild and shift west. This will have the tendency to block Ivan from coming north and send it into the Gulf of Mexico. However, if the high does weaken and Ivan ends up near or over Hispanola, that would open up the East Coast or even Florida to risk for landfall if Ivan begins to turn north after Wednesday or Thursday.

(4) Ivan is over waters that were not disrupted by Frances. That alone will serve to help this storm reach it's maximum possible strength.

A word to our loyal readers out there... if you come across an interesting website dealing with severe weather, hurricanes or snowstorms, please post a comment indicating the site address and I can add it to the link library.

Next update Tuesday morning.

No comments: