Debby Dilemma

Wow… would not like to be sitting in the forecast chair at the National Hurricane Center this morning. Looks like we will have a slow moving hurricane in the Gulf of Mexico; models are all over the place, and steering currents are basically non-existent.

Here is their early morning update on Tropical Storm Debby… they have made a big shift to the right on the forecast based on the 00Z model set, and bring Debby to hurricane strength Tuesday night…

**Note NHC has now issued a tropical storm warning for the Alabama and Florida Panhandle Gulf Coasts as of 7:00 a.m…

The latest model spaghetti plot is more confusing than ever…

Models shifted to the right last night, and the idea of a Texas/North Mexico landfall is becoming less likely. Higher odds are from Louisiana eastward now. Climatology supports this idea as well. It all depends on the strength of the upper ridge to the north of the system, and any weakness in that ridge that develops.

Below is the early morning surface analysis, which shows the pressure down to 1000 mb…

Enough of all this mumbo jumbo… everybody wants to know the impact on sensible weather around here. Some points…

*Odds are high this will bring no really significant rain to the northern half of Alabama due to a strong upper ridge that is forecast to be in place, unfortunately.

*Very rough surf and rip tides will continue along the Gulf Coast from Gulf Shores to Panama City. Beaches at Gulf Shores and Orange Beach are technically closed due to this danger, and red flags are flying as well along the coast of Northwest Florida.

*The Gulf Coast will deal with occasional showers and storms through at least mid-week, but the rain won’t be continuous. Debby is a sheared system now, and the convection remains displaced from the center for now. Below is the RPM rain forecast through 27 hours… some big numbers mainly from about Panama City down through Tampa Bay and Fort Myers. This rain mass should slowly shift northward with time, but only very, very slowly.

Below is the NAM rain outlook through Wednesday….

*People are asking if they should cancel their Gulf Coast vacation this week. That is a very personal question I can’t answer… if you main objective is swimming in the ocean, then don’t go. But, otherwise the rain down there won’t be continuous, and the sun will be out at times.

*How strong can this system get? Below is the intensity forecast from various models…

As you can see, most models keep Debby as a tropical storm, but with 28 degree (C) water, no doubt this could become a hurricane. I doubt if it gets past category one, but not totally out of the question. The main impact one way or another will be from heavy rain, flooding, and dangerous surf once this thing finally goes ashore sometime late in the week ahead.

*There is great, great uncertainty in this forecast, so keep an eye on the blog for changes in coming hours and days. Brian Peters and Bill Murray will have updates throughout the day, so check in with us often.

Tags: debby

Category: Tropical