Tennessee Valley Weather

Oh Bother . . . Where Will This Hurricane Land . . . . ?

By: mgwxta19, 3:27 AM GMT on August 27, 2012

Note: Since this is my first post on here . . . I forecast from North Alabama and sometimes focus on the adjacent counties to the North in Tennessee. The beach forecast, which I post in summer for Gulf Shores, is taken from the NWS forecast - local forecasts are my own. I'm just now getting a feel for this site, so be patient with me . . . have kept a weather blog of my own for a while. FORECAST:



Monday: Mostly sunny. High 89, Low 67



Tuesday: Partly cloudy with a 30% chance of showers. Breezy. High 88, Low 68



Wednesday: Mostly cloudy with a 50% chance of showers. Rain could be heavy, and winds could gust high enough to cause minor damage - mainly later in the day and into the night. High 83, Low 70



EXTENDED OUTLOOK:



Thursday: Cloudy with heavy rains and high winds likely. High 78, Low 69



Friday: Mostly cloudy with a 40% chance of lingering showers. High 81, Low 67



Saturday: Partly cloudy with a 30% chance of lingering showers/thunderstorms. High 84, Low 65



Sunday: Partly sunny. High 86, Low 64



BEACH FORECAST:



Monday: Partly cloudy with a 40% chance of thunderstorms. High 89, Low 74



Tuesday: Hurricane conditions likely. High 84, Low 79



Wednesday: Tropical storm conditions still possible. High 88, Low 78 



(Personal opinion - just don't be down there right now. They are evacuating, anyway.)



NOTES:



If you haven't already done so, now is the time to review your hurricane preparedness, particularly if you are close to the Gulf Coast. Even those of us in North Alabama could stand to glance at this though.



And here is another nifty page from NWS Mobile with all kinds of information on the tropics.



I would encourage everyone to tune in to the WeatherBrains Podcast tonight at 7 p.m. These guys are going to do an in-depth discussion on the tropical situation.



DISCUSSION:



















It was a mostly sunny day today in Cullman and the rest of the TN Valley. Our High was 88. Our Low was 66. Huntsville made it up to 90. Muscle Shoals made it up to 91. Fairly low humidity. Pretty good weather for late August.



But tropical season is well underway, and obviously Tropical Cyclone Isaac is getting ready to knock on our back door down at the Gulf Coast within the next couple of days. After watching is so long, it's somewhat surreal to see such a good presentation on local radar/satellite.









Our winds are still northerly, and we are so clear and dry because we have some subsidence from T.C. Isaac moving closer.









Tomorrow the GFS model has Isaac moving just slightly to the northwest, affecting a large area of Florida. I do want to note that there have been no reports of tornadoes with this so far. However, if it does strengthen to a hurricane tonight/tomorrow, that could change.









The NAM model has it in a similar position but a tad weaker.









By Tuesday the GFS brings it to the coast of New Orleans or Biloxi, Mississippi, that vicinity. We could see a few spiral bands of showers later in the day Tuesday if this pans out.









The NAM has it just south of Pensacola at the same time.









At this point the GFS gets hard to "buy," as it takes it well into Louisiana. I think that's just going too far from previous guidance, way too far out west. That's just my opinion. This is for Wednesday.









The NAM is showing landfall on Wednesday around Destin, Florida. So already you can probably see why the Hurricane Center has a warning up from Louisiana to the Florida Panhandle. Things have not come into better focus, and at this point each forecast (including me) is just going to have to make his/her best call.





The ECMWF has landfall around Mobile or Biloxi Wednesday morning and a pretty wide-reaching circle of bad weather out to the north and east, which would affect us with flooding rains and sustained high winds.









The GFS moves it into Texas on Thursday, but at this point I think I may drop that guidance. All bets are off . . . right now we're just trying to nail down where the storm is going . . . what is does after that is not all that interesting to me at this point. First things first.





The ECMWF has really rough weather for us on Thursday - flooding rains, high/damaging wind gusts, and perhaps a few brief, isolated tornadoes. Pick your poison; the models continue to be all over the place.



All bets are off beyond Thursday, but in any case, the storm should be moving out of our area (or already out) by Friday and the weekend. Some moisture will probably try to linger and kick off some showers/thunderstorms though.









The tropical models are still trending west, but a lot of them have come back east a bit, showing a track along the Mississippi/Alabama line, which is closer to the official NHC track and certainly rings truer with me.



The intensity guidance mostly takes this up to only a category-1 hurricane, and indeed, although the waters appear favorable and all, Isaac remains a tropical storm for the moment. There is still some chance that it could intensify into a more significant hurricane, but since the time has come to make some decisions, then my forecast for the moment will be based on it being a category-one or two at most.









The satellite presentation looks pretty good - I think I can see a fairly well-defined eyewall developing. The official forecast track from the National Hurricane Center in Miami calls for this to make landfall on Wednesday between New Orleans and Biloxi as a Category 1-2 Hurricane and then to drift north/northwest inland. On this track, we would have a few issues in North Alabama with heavy rains and perhaps some minor wind damage, but it would be far enough away that most our problems would likely be west of I-65. Also more likely in our southern counties like Cullman/Winston/Marion. It's important not to get too hung up on the specific track since there is still much uncertainty, but in the same breath, time is ticking away, and this is the best we've got to go on.





There are places along the extreme Gulf Coast that may see well over a foot of rain, horrible flooding conditions. Around here, we'll probably see at least six inches of rain from this tropical cyclone.






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Everybody make what preparations you think best, and I'll see you in the funny papers. This storm is no laughing matter, wherever it lands.



As a matter of fact, Mobile and Baldwin counties are being evacuated, and Governor Bentley has just declared a state of emergency. These evacuations are mandatory, by the way.

Forecast, Tropical

Updated: 3:36 AM GMT on August 27, 2012

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About mgwxta19

Howdy. I'm a former weather student who likes blogging but is sometimes distracted by boring things like magic shows or fun things like regular work.