Friday, October 26, 2012

Hurricane Sandy: October 26, Update B

‘Hurricane’ Sandy is still out there. She’s really not a hurricane any more, but more of a Tropical Storm and the NHC know this too… but I think they are waiting for confirmation from an Air Force hurricane hunter plane before downgrading her. I think she’s been a Tropical Storm for a number of hours now. So far, Sandy has been a relatively straightforward storm… but now it gets a little tougher.

Track: She is officially at 27.7N, 77.1W, moving N at a very slow 7mph. To me it looks like she’s moving a little slower than that, which means she is still stuck in an area of high pressure. In fact I don’t see her moving anywhere fast in the next few hours. Regarding her future track, I can see that she will start moving generally northward when the high pressure breaks, but whether it is northeast or northwest depends on when she starts moving. At the moment it looks to me like she could even head for the Carolinas if she started moving soon! I find it interesting that because I’ve already seen the forecast track I think I can see what the models are predicting will happen. Without knowing the forecast track ahead of time, I would not have come to the same conclusion. I think this is the first known example of Schrodinger’s Track!! ;-) In this case I would really go with the NHC track because the models for the track (not intensity) have been doing very well lately! (so well that I might even be able to go into semi-retirement next season! ;-)).

Intensity: Officially she has winds of 75mph, central pressure 969mb. This makes her barely a cat 1 hurricane (cat 1 range: 73-95mph). The buoy in the Atlantic that is closest to her (from the SECOORA website - details were in the last update), about 150 miles from the center, is now showing that winds have increased to 54mph, with pressure at 990mb. Storm surge from the Tides Online website is showing at the most 1.5 ft above normal. As you know, she is experiencing very strong wind shear and dry air. Here is the latest water vapour satellite image of her (she’s that cloudy area just east of Florida) and the entire north Atlantic so you can see the extent of the clouds streaming away from her to the north:

You can also see the front that they think will cause a bit of a ruckus when it meets her in a couple of days… it is that line of clouds that is stretching from the northeast to the southwest, ending over Louisiana and Texas. I think she will continue to weaken, maybe down to a weak-to-mid strength Tropical Storm. In addition to the dry air and wind shear, water temperatures are a little cooler at 27-28 deg C (still warm enough to sustain her), with the upper 50-75m warmer than 26 deg C.  

The forecast for Sandy says that she will re-intensify into a hurricane on Sunday afternoon because she will interact with a low pressure front. I am not sure she will be quite as strong as they are forecasting, but the bigger effects will be from winds and storm surge along the coast. Here’s an article from USGS that covers the wave impacts they expect to see along the beaches on the Delmarva Peninsula (Delaware, Maryland, Virginia), New Jersey, and Long Island (New York) (from Karen): http://coastal.er.usgs.gov/hurricanes/sandy/.

That’s all for today. Tomorrow is the St. Petersburg Science Festival, so come along and see some FUN science stuff! I’ll be hanging out with the cool kids at the Florida Institute of Oceanography table… stop by and say hello if you are in the vicinity of the USF-SP campus.

And for my friends in the states north of here (or elsewhere)… let me know if you have any questions!

Ciao for now,
J.

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

-------------------------------
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.
-----------------------------

No comments: