Saturday, October 27, 2012

'Hurricane' Sandy: October 27, Update A

Mother Nature has upstaged American politics. With 10 days to go before the Presidential election, Hurricane Sandy was a higher ranking news item (from what I heard), followed by the changes in the candidates’ schedules because of the storm. Science is important! :-)  

The NHC had a brief moment of clarity this morning and downgraded Sandy to a Tropical Storm, but then decided that too many people would think that would sound just like a walk in Central Park, so they better call her a hurricane after all. Sigh. Officially she now has winds of 75 mph, central pressure 961mb. This makes her very barely a cat 1 (cat 1 range: 74-95mph), so calling her a Hurricane is really for the psychological impact.

She is at around 30.5N, 74.7W, heading NE at 13 mph, and is pretty much on that NHC forecast track. Given the data I have today, I would agree with their general forecast. The slower she goes, the farther north will her landfall be. At the moment it looks like landfall will be in Delaware, but if she slows down, then her landfall will be farther north. She is forecast to make the turn to the north and then northwest tomorrow evening.

Here is a visible satellite image of Sandy (taken at night, so a little dark, but you can see her center), as well as the matching infrared satellite image so you can see how much convection she has:

For all you new kids tuning in (hello & sorry about the circumstances!), the blue area is mostly cloud, the light yellow is light rain, the dark yellow/orange is heavy rain, and if I show you an image with red surrounding dark gray, that means thunderstorms and possible tornadoes. As you can see, she is mostly just clouds and light rain, nothing too strong at all. For those of you who remember Irene last year, Sandy is nothing like that. Nowhere near the same amount of rain!

Also, here is an infrared satellite image of the Northwest Atlantic so you can see Sandy in a larger context:

The concern really isn’t Sandy-the-tropical-storm (which alone is pretty weak), but Sandy-the-hybrid-tropical-storm/low-pressure-front. The front has almost merged with Sandy’s western flank – you can see the ‘straight’ line of the front, it is currently over western Florida and Georgia/Tennessee/Kentucky/Ohio etc. The front also doesn’t have much rain in it either. So Sandy will be a windy, with some some storm surge (and a bit of rain).

The storm surge on the eastern seaboard (from tides online; see this entry for instructions on how to do this: http://jyotikastorms.blogspot.com/2012/08/tropical-storm-isaac-august-26-update-b.html), is highest in Virginia at the moment, with water levels at Sewells Point and Money Point on the southern side of the Chesapeake Bay showing water levels at 2 ft above normal. Although the winds are not very strong (about 35mph max), the wind direction is just right in blowing water into the Chesapeake Bay estuary and onto the southern shore.  

<Observations Alert>Yesterday I told you where to look for some fabulous real-time data in the Atlantic and along the coast from Florida to North Carolina. If you want to see what is going on in the ocean and along the shoreline from Cape Hatteras, NC to Cape Cod, MA, look here: http://assets.maracoos.org/. On the lower left panel, click on the button next to ‘Turn all models off’ under the ‘Models’ section so you can actually see the stations with real observations clearly. Also make sure there is a tick mark in the top 5 boxes under the top left section called ‘Point Observations’ so you get a larger range of coastal stations as well. Then scroll over the dot (station) on the map that you are interested in, and click to look at the real data. If you click on the graph looking icon next to the observation you are interested in (for example, wind speed in mph), the graph at the bottom of the page shows a timeline of those observations. You have to close the ‘data’ box to see the graph though. Ta-da. <End Observations Alert>   

It looks like there are a lot of preparations going on for ‘Hurricane’ Sandy in the Virginia/Maryland/Delaware/New Jersey/New York area today, for example, as seen on a shoreline in New Jersey…...

I’ll be back with more tomorrow! Time for a glass-o-wine and a bit of Saturday night classic British TV… As Time Goes By (which, coincidentally has a character called Sandy!). :-)
Ciao,
J.

p.s. Ok, ok, actually, that photo is one I took today at the science festival… thanks to the anonymous person who let me take that photo of his t-shirt! J

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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