Sunday, June 24, 2012

Tropical Storm Debby: June 24, Update C

The 5pm update from the NHC has shifted her track to the east so the center of cone is now directly heading into the Florida Panhandle with landfall on Weds. afternoon.  They have removed the warnings for Louisiana. The ‘cone’ takes her anywhere from Alabama to the Big Bend/Cedar Key area of Florida. I think we are more on target with this. If she is heading to the western side of this range, we’ll see her turn to the north and then northwest in the next few hours, so that’s something to look out for today.

She is at 28.4N, 85.8W and still more-or-less stuck, crawling NE at 3mph. She must have had one too many martini’s yesterday! Winds are 60mph, with a central pressure of 993mb.

Her convection is currently taking a hit from many sides. Not only is she already interacting with land (as everyone in Florida can attest to!), but she is no longer over the Loop Current and there is still a little bit of shear. I mentioned these earlier today. But there is another factor that will help us a bit: the western Gulf has some dry air that she is pulling in, which is why the really strong thunderstorms are diminishing (or will be soon). You can see this in the latest infrared satellite image:
Compare this to the one I sent out earlier and you’ll see a huge reduction in the really cold cloud tops (the red areas). This means that the parts of the storm that are currently producing tornados will decrease, as will the really heavy rain over the next day or so. They won’t completely vanish, but it shouldn’t be as it was today. We’ve had a lot of rain over the past 24 hours – almost a foot in some places in Pinellas County.

However the wind shear has definitely decreased and with that her circulation has improved in all levels of the troposphere. If she had more convection, she would be a category 1. This means that even though the convection won’t be as ferocious, it will still be windy tomorrow and on Tuesday at least. There are two problems with this. First, because she is not moving very quickly, water from the Gulf will continue to be pushed on-shore along some parts of the coast. Water moves (along with the winds) in an anti-clockwise direction around a low pressure like Debby. Her center is north of Tampa Bay, so the water will be blowing into Tampa Bay. On the other hand, water will be blowing away from the coast on the northwestern edge of her circulation. This will mean that the coastal flooding will continue. Currently the surge is 2.5 ft above the normal tide in the St. Petersburg area, and 3ft above the normal tide in Apalachicola. We are at high tide in many places now though, so actual water levels are much higher. The second problem is that as her wind field strengthens and expands, she will be pulling in moisture from a larger part of the Gulf. This may result in more convective activity– she is already pulling thunderstorms from the Yucatan area into the northeastern Gulf and across Florida.. So… depending on how long she stays in the Gulf, she may actually become a hurricane before all is said and done.

A lot of reports of damage from downed trees, tornados and high water are coming in. Thanks to all the intrepid reporters on the ground who are sending me videos and photos! I am going to try and put a couple of videos from Steve M. from St. Petersburg on my blog (jyotikastorms.blogspot.com). One was at Pinellas Point just after noon today:
video


The dock that is in that video was destroyed four hours later. He also sent me a video from Coffee Pot Bayou in St. Petersburg at 5.40pm, which shows a lot of flooding:

video


From Shore Acres in St. Petersburg, Molly M. sent this photo of a car driving through some of the street flooding:

Also here is a photo of a downed tree branch from Dawn M. in St. Pete (luckily it missed her house):

It is now just windy where I am. The rain has lightened up and the sky is brighter. It’s wine-o-clock! Yay! I’ll attach more photos in the next update.

Stay safe out there!
More later,
J.

p.s. I’m sick of ice cream. For today anyway. ;-)

Blogs archived at http://jyotikastorms.blogspot.com/
Twitter @JyovianStorm

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DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.
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