Wednesday, August 22, 2012

I Would Rather Have One Of These "Isaacs" Hit The U.S.


2:35 PM Thursday Update... That darn European model is giving forecasters fits right now.

There's always the "what if" when you see what it's showing.  Keep in mind, it has been the outlier model as many of the others show the track of Isaac much further to the east.  Some so far east that it never gets into the Gulf of Mexico.  The official track brings it into the far eastern Gulf affecting Florida and maybe the beaches of Alabama.  Remember this is going to change since this is still very much in the long range. 

The Canadian model run Thursday morning brings Isaac along the western coast of Florida then moves it into Georgia.  This is valid next Monday morning and it's well east of Arkansas

The European model shows the storm in northeast Texas next Friday morning.  This is NOT good news for Arkansas.  This would place us in the dangerous sector of the storm with flooding and severe weather.  REMEMBER, THIS IS THE ONLY MODEL SHOWING THIS AND IT'S AN OUTLIER.  IT DOESN'T HAVE MUCH OF A CHANCE OF VERIFYING, BUT IT MUST BE WATCHED!!!!!!

6:40 AM Thursday Update...  Right now, there is enough uncertainty in the long range to keep a close eye on Isaac.  The most likely scenario would be a track well east of the state towards the western coast of Florida and maybe as far west as Mobile, AL.  If the storm takes this track, the main effect on our state would be very warm temperatures and super dry air.  A strong tropical system results in strong upward movement of air, to counter that, around the periphery of the storm, a strong downward motion to the air results.  This is called subsidence.  I have seen situations before where a strong tropical system produced such strong subsidence that it dries the air and temperatures can soar well past what the models project.  So let's keep that in mind as we watch the intensity and location.

If the storm tracks far enough to the west, we could get some wet weather.  While that's possible, it's unlikely at this point.  Even the Euro, which has been the outlier showing a far westward track, has moved the storm slightly to the east in its latest run.

Check out the models below from Thursday morning

Everyone likes to give credit to the Euro as it shows a far west solution.  The NAM is completely the opposite.  It brings Isaac east of Florida Sunday.

The GFS shows a more southern and eventually a more westward track.  It has been fairly consistent with the storm impacting the west coast of Florida up to the panhandle.  This is what the Tropical Prediction Center is following right now.

This is the latest European model and its solution is furthest to the west with an impact near Mobile, AL.  So you can see the spread in all the models, but whatever model you buy into, the track is east of Arkansas.  You DON'T want to be on the eastern side of one of these storms.  That's severe weather and flooding.  I know we need rain, but tropical rains can be devastating and sometimes it brings tornadoes.


"The Love Boat" tune will be playing in your head for the rest of the day now won't it?

So where will Isaac go?  The models diverge as he heads towards Florida.  Will he go up the east coast, move across Florida, or continue more to the west into the open Gulf and pose more of a threat to the Gulf coast states?  It should be noted that only one model brings Isaac far enough to the west to impact Arkansas and that's the European.

You may remember Tropical Storm Debby in late June.  Debby was forecast by the European model to make a westward track towards Texas and many forecasters including the Tropical Prediction Center bought into that track.  However, the GFS (thought to be "out to lunch") insisted on a more easterly track towards Florida.  At one point, the Euro started to change its tune and forecasts literally changed 180 degrees.  Debby went east giving the GFS a much deserved and needed victory.

With all that said, I urge caution on a far westward track towards Arkansas.  While it's within the realm of possibilities, I think a track further to the east is more likely.

I know we want rain, but tropical systems are NOTHING to play around with!  They don't bring needed rain usually, they can sometimes brings devastating floods.  So be careful of what you ask for!  IF the storm were to make a move to the west, Arkansas would likely be on the west side of the circulation.  This usually brings the least amount of rain and severe weather.  The system would have to track up towards the Arklatex, then go more north to bring a threat for severe storms and flooding.  But like I said, I think a more easterly track is likely, but we'll watch it for you.

The Love Boat, soon we'll be ..... nevermind... check out the model maps below.

This is the Wednesday morning run of the European valid next Wednesday morning (7 days away).  It continues to show a track far enough to the west to raise concerns for our neck of the woods, but check out the other model solutions below.

This is Wednesday morning run of the Canadian model valid next Monday morning.  It indicates a more east coast threat with Isaac hitting the coast of north Florida into Georgia.  Believe it or not, few storms actually have made a direct hit in this location.
The latest version of the GFS shows it near south Florida Monday morning with a move up the west side of the Florida peninsula.
The official track from TPC shows it crossing several land masses which could tear it apart some, then strengthening into a Hurricane along the west coast of Florida.  This looks like the GFS solution here.


Anonymous said...

Wasn't Gustav in 2008 the last time we saw really "significant" rain from a hurrican landfall?

When was the last time the contest was updated? It still shows a date of August 7.

Will said...

Wasn't the Euro the one model that was indicating Isaac in the Gulf 3 days ago? Just because it's the only model showing something does not mean that it won't be the one that verifies.

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