Tuesday, September 7, 2004

FLOODING FRANCES REFUSES TO LOOSEN HER GRIP ON THE EASTERN U.S

Hope you're not getting sick of my alliterated (sp?) headlines. Just trying to keep the weather interesting and fun.

Flood Watches are blanketing the northeast from Georgia to New York. Poor, poor Richmond has already issued a Flood Statement, and the twisting, churning mess that is Frances continues to slog her way up the spine of the Appalachians. Do not be surprised to hear rainfall amounts in excess of 10 inches out of this storm. The 95 corridor will be spared that kind of rain, but it will be a heavy, wind-swept tropical-like rainfall for the next two-three days from DC to NYC.

Rainfall amounts will be 1-2 inches east of I-95 from DC on north, and 2-3 inches west of 95 to the mountains. Once you are in the mountains, rain will probably exceed 4 inches in many places, with isolated locations topping 6 inches or more.

IVAN IGNORES ISLANDS ... SETTING SIGHTS ON SUPER-HURRICANE STATUS

This monster storm ripped through Grenada and Barbados, and then never looked back as it just intensified to Category 4 with winds of 135 mph. Forecasters expect it to strengthen beyond their projections, as it has been a long time since we've had a storm of this magnitude in the deep tropics. Computer models continue to weeble-wobble around Haiti, Cuba and Florida. I did take a look at the historical track of storms that followed a similar path, and it is an eerie sight. Many took a swipe at Florida, some charged all the way up the East Coast, after having just spent time grazing the beach in Barbados. Seems weird a storm would start so far south, and then end up coming so far north.

The conventional wisdom from Accuweather and the NWS is that this storm is entering extremely warm ocean water, which will further strengthen the storm to Category 5 status. If it enters the Gulf of Mexico undisturbed by land, and no other forces influence the storm (such as a trough diving south or dry air filtering in), Ivan has the potential to do the unthinkable...

Approach major population centers along the Gulf Coast as a Category 5. This has not happened since Andrew in 1992, and one of the strongest storms in U.S. history... Camille in 1969.

RECURVING PACIFIC TYPHOONS INDICATE TROUBLE FOR THE NORTHERN AND EASTERN GULF (YES, EVEN FLORIDA).

The whole of the atmosphere has many complex inter-relationships. Forecasters call it "teleconnections" and it is easy to see why the weather in one part of the world strongly influences what goes on elsewhere. One of the phrases used by Accuweather forecasters in winter is "A ridge in Spain, warm up and rain." That means if there is a high pressure system in the vicinity of Spain, the airflow across the Atlantic is such that is brings the subtropical jet far enough north to turn a snowstorm into a rainstorm along the Mid-Atlantic.

Take that same teleconnection and apply it to the recent typhoon activity in the Pacific. The western Pacific, namely Japan and China, have had a super-busy typhoon season. Several of these storms have reached super-typhoon status (Cat 5 on our scale). Most of them have followed a very similar path of "recurvature" through Japan and then rapidly north-northeast. All of these events occurred roughly 10 days before major hurricane strikes on the East Coast. And what did those storms all do? They eventually took a right turn and charged north-northeast.

Take a look at the tracks of Atlantic hurricanes thus far this season. Notice the persistent curving to the right just above 30 degrees north?

Now look at Super-Typhoon Chabra… and notice the similarities in the track. Just after 30 N it turned sharply to the right.

What I am saying is that Ivan may pull the same trick once it crosses Cuba if it continues on that path. now seems clear to forecasters and computer modeling programs alike this storm is not going to get anywhere near eastern Cuba or Haiti or Puerto Rico. All eyes are turning to the tip of western Cuba at the first spot for probable landfall.

And the hurricane center has been very accurate in their day 5 estimates of the storm location. I looked back through the maps I had printed out of Frances’ path. Even as early as the 30th, they were projecting a landfall on the southeast Florida coast by 2AM Saturday. It arrives at 1AM in pretty much where it was originally forecasted to go.

SO IF IT RECURVES AFTER CUBA, WHO IS UNDER THE GUN THEN?

If we extrapolate this recurvature 2 days beyond the day 5 projection of western Cuba…then the likely area of high risk for landfall would be from New Orleans eastward to about the area where Frances made her second arrival (St. Marks). The time frame would be as follows...

Recurving to the north and northeast...landfall on Tuesday or Wednesday between New Orleans and Appalachiacola, FL.

Curving north and then northwest...landfall on Wednesday or Thursday between LA/TX border and Galveston.

City planners, forecasters and the government have feared a major hurricane strike on New Orleans as explained in a USA Today article. It would be catastrophic beyond anything you have ever seen in your life before or in the future. Lake Ponchartrain and the Mississippi River would both overflow their levees, flooding Big Easy's downtown with 20-30 feet of water. There is only one route out of town... the causeway over the lake. It would take 72 hours to evacuate the city, but warnings are only posted 24 hours in advance. The Army Corps of Engineers estimates the loss of life at such a staggering number that I won't print it here. If you want the gory details, read the NPR article linked above.

But enough doom and gloom for one day.

WILL WE GET A BREAK FROM THIS RELENTLESS HURRICANE SEASON?

Yes. Accuweather has indicated in their long range analysis that the pattern of Africa pumping out storms one after another is about to die down. In addition, the excessive number of active systems in the Atlantic is beginning to stabilize the water temperatures. So when we are done with Ivan, it should calm down for a brief period. But remember, we still have half of September and all of October...which is when the Gulf starts to get busy.

Brief update Wednesday morning, then full update Wednesday night or Thursday morning on the status of our recurvature ideas.

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