Tuesday, November 8, 2011

Not much reason for discussion other than there is a new tropical storm. Sean has developed from the low pressure system northeast of the Bahamas but posses little threat to land, even Bermuda.
The system has been nearly stationary since late last week. This is not to say there hasn't been some impacts to winds and seas along the southeastern United States. Gale force winds over the weekend have diminished somewhat but the swell and wind waves from the low are still a factor.
From the National Weather Service WaveWatch III model the image below shows the current conditions off the east coast of Florida.
The GOES East satellite image below shows tropical storm Sean northeast of the Bahamas.
In the image above we see there is a trough across the Mississippi Valley, this trough will absorb the storm at first taking the upper level low off to the northeast. The upper level low associated with the trough will spawn a short wave the will pick up and surface and low level feature and by day 5 with a more pristine wind and wave environment expected. Below is the 5 day WaveWatch III forecast for Florida's east coast.
Sean has a very weak asymmetric warm core signature and should shift quickly to deep cold core (non-tropical) as the trough interacts with the system. The phase diagram below is from Dr. Bob Hart FSU.

Have said a lot for not much of an impact-full system, but it is an interesting late season anomaly.
On a different note, 2005 YU55 will pass very close to the Earth tonight. This asteroid will be within 201,000 miles of the planet and visible with the naked eye. A view through a telescope should be amazing.
BC