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Wetter Weather to End September

| September 27, 2015 @ 7:12 am

Special thanks to Bill Murray for subbing for me yesterday. Meaghan and I had a great time visiting with people at the Cullman airport as skydivers were waiting for the clouds to break up. The event was a fundraiser organized by Dustin Chandler of Hoover, AL, benefitting children with CDKL5. CDKL5 is a rare neurological disorder that often causes seizures and impaired neurological development.

Turning to our weather, we have a rather interesting and somewhat complex weather pattern that we will be dealing with for today and over the next several days. This morning, high pressure centered over southern New England is creating a weak wedge or cold air damming pattern over the Southeast. The wedge is rather weak so it is influencing mostly the northern half of Georgia and the Alabama counties along the state line. Besides the temperature contrast, several ground observing stations were reporting some light drizzle though little if any of that was showing up on radar.

At 500 millibars, the weak upper low that we dealt with yesterday has moved northward into Kentucky while a broad closed low was situated over Texas extending into the Northwest Gulf. Back at the surface, we’ve also been watching an area of disturbed weather located along the eastern shore of the Yucatan Peninsula moving slowly but steadily northward. All of this spells a period of wet weather for much of the Southeast US especially the area along and east of the track of this weak low.

The weak low along the eastern shore of the Yucatan Peninsula will move northward into the Gulf where conditions are marginally favorable for some intensification. This area of disturbed weather could organize some which means it has the potential for becoming a tropical depression or perhaps a tropical storm. Water temperatures in the southern and central Gulf are running in the lower 80s but wind shear appears likely to keep the system from strengthening much. But no matter what this is or becomes, the flow of a lot of tropical moisture into the Southeast US will spell some significant rain along and east of the weak low.

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Further out in the Atlantic, NHC is still watching Ida which remains a tropical depression and is not likely to gain any strength primarily due to shear and dry air. About 425 miles south-southwest of Bermuda, an area of disturbed weather is moving northwestward and there is a brief window of opportunity in which it could organize enough to become a depression. However, after a couple of days, conditions will become much less favorable.

The weather has turned wetter along the coast overnight as this tropical moisture streams northward causing widespread showers and storms along the Gulf Coast. The next few days look to be pretty wet along the Alabama and Northwest Florida Gulf Coast with drier weather toward the latter part of the week. Note, too, that the strong onshore flow along the coast has brought conditions favorable for rip currents, so beach goers will want to use caution about venturing into the Gulf water. See the complete Gulf Coast 7 Day Planner here. The Gulf Coast Beach Forecast is presented by Gulf Shores Plantation by Mandoki Hospitality Vacation Rentals. Escape to Gulf Shores Plantation where memories last a lifetime.

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This weekend’s full Moon is a “supermoon,” the biggest and brightest of the year, and it is about to be eclipsed. This evening sky watchers in North America will see the big lunar orb glide through the shadow of Earth, turning it a beautiful shade of sunset red. The same eclipse will be visible from South America, Europe, Africa and parts of Asia during the early hours of Sept. 28th. Unfortunately, I am afraid that clouds may impact our viewing opportunities in Alabama. Some viewers may be able to see it should some breaks in the clouds occur.

Looking at modeling, we’ll follow the GFS though it may be missing the mark a little. But I’ve noticed over the last several days that the Canadian, European, and American (GFS) models have been all over the board on projected solutions. With the weak closed low over Texas, there is consensus that there will be a flow of tropical moisture from the Gulf into the Southeast US. The weak low along the eastern coast of the Yucatan peninsula is expected to move northward and produce heavy rain along and east of the track of the weak low. The GFS has been more consistent in bringing this up into the coast of Northwest Florida, so the heavy rain threat is most likely to be over North Florida, Georgia, and the Carolinas. For us in Alabama, it looks like we will benefit from a steady rain over a couple of days amounting to around an inch to perhaps 2 inches with 2 to 4 inches along the coast from New Orleans to Tampa, FL.

An upper trough in the westerlies moving along the US-Canadian border will pick up our closed low over Texas late in the day Monday and bring it out across the Lower Mississippi Valley. This establishes a trough over the eastern third of the US and with a good northwesterly flow, we should see drier air push into Central Alabama toward the latter part of the week.

But the GFS goes all wonky in the Thursday-Friday time frame with a complex pattern featuring a very large and broad closed low centered over the Ohio River Valley. This pattern just looks funny, so confidence in the forecast for the latter part of the week goes down significantly.

By Sunday a week from today the GFS organizes the pattern a good bit with a deep trough over the eastern US with the trough axis on Alabama. This certainly looks like a nice cool down, however, the MOS guidance out of the GFS doesn’t seem to cool down our highs very much, but it does show the drier air with dew points in the 50s.

Looking out into voodoo country, the GFS keeps the trough over the eastern US out to around the 8th of October but builds in a weak ridge as we get out to the 10th through the 12th.

James Spann will have the next Weather Xtreme Video here first thing Monday morning. Be sure to check back here for updates on the Central Alabama weather. Have a great Sunday, and Godspeed.

-Brian-

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Category: Alabama's Weather

About the Author ()

Brian Peters is one of the television meteorologists at ABC3340 in Birmingham and a retired NWS Warning Coordination Meteorologist. He handles the weekend Weather Xtreme Videos and forecast discussion and is the Webmaster for the popular WeatherBrains podcast.

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