Sep 8, 2011

DAY 99

There are now 3 active named storms in the Atlantic Basin. Tropical Storms Maria and Nate both formed today. But the only hurricane on the board is still Katia. She is now a category 1 hurricane with just 80 mph sustained winds and a pressure of 982 mb. The microwave satellite image shows that Katia has got some major problems with the west side of her eye-wall. She is just barely a hurricane really. 

(Hurricane Katia Microwave Satellite)

Hurricane Katia has started to make a bit of a turn. Her heading is now NNW. She is forecast to remain a category one hurricane as she makes a full turn to the northeast and then this weekend accelerate towards the UK. Katia will become post-tropical as she hits the cold water of the north Atlantic, but is forecast to remain a named cyclone all the way to Scotland. You don't see the little "H" symbol inside a white post-tropical dot very often. I guess what the NHC is trying to tell us is that Katia will lose her tropical characteristics, but remain at hurricane strength. The question then is what do we call her? I've never hear of a post-tropical hurricane before, so I guess we'll call her "very strong post-tropical cyclone Katia".

Tropical Storm Nate has formed in the Bay of Campeche today. He is our 14th named storm this year, so we only have 5 more to go to catch last years active hurricane season of 19 named storms. And this is the 2nd earliest time that the "N" storm has formed, only 2005 was earlier and that was just by 2 days. The time-lapse shot from the visible satellite shows a very active system. Thunderstorms are blowing up so high that their hitting the Tropopause and flattening out, this is a sign of a strengthening system. You can also see below the convection, surface clouds spinning cyclonicly around an area that a Hurricane Hunter recon mission found a closed circulation earlier today.

(Tropical Storm Nate)

The forecast for Tropical Storm Nate is very tricky. This is only of those storms that Recon Flights will prove very important. Nate will likely meander about in the Bay of Campeche for a couple of days before revealing it's true intentions. It looks like Nate is well on his way to become our 3rd hurricane of the season, unless he runs into the Yucatan Peninsula.

The front that he was attached to before becoming tropical is moving off to the northeast, so that seems like a possible path that Nate could follow in. The Hurricane Center is going with a forecast that favors the weakening of a ridge of high pressure over Mexico to break down in a couple of days, drawing Nate onto Mexico's eastern shore. There is actually now a model consensus for that as well.

Tropical Storm Maria is struggling a bit with some dry air in the central Atlantic. She does still have a broad cyclonic spin, but she lacks focus. Maria has 50 mph maximum sustained winds and a pressure of 1002 mb.

(Tropical Storm Maria)

Maria will have to contend with that dry air all the way to the Antilles Islands. The NHC's forecast track keeps Maria below hurricane strength all the way through it's 5 day forecast. Maria is expected to reach the northern part of the Lesser Antilles by Friday night then move just northeast of Puerto Rico on Saturday night.

The forecast models agree with this track for the most part. The trend is still to guide Maria away from the Bahamas and out to sea.

There is one other thing that sticks out in my mind tonight. On the water vapor image below, you can make out the long front over the eastern US. Usually when those things start making their way all the way down the Florida peninsula like this one did, that is signifying that hurricane season has more days behind that there are in front. These will take their toll on the Bermuda High, and Cape Verde type storms will start to take more northward paths. Our focus will soon start to shift back to the Caribbean soon. The current setup with Maria and Nate are a testament to that.

(Continental US Water Vapor)

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