Disturbance brewing off Panama coast...

With less than a week remaining in the official Atlantic hurricane season, an area of persistent convection has been festering in the extreme southern Caribbean Sea, just off the northern Panama coast.  It's been there for well over a week now, stationary, yet growing in size and ever so slowly getting better organized.

An active microwave scatterometer, a satellite-based instrument which indirectly measures surface wind speed and direction over water, detected reliable winds in the disturbance up to 35kts this morning, but more commonly in the 20-25kt range.  There is moderate southwesterly vertical shear over the system, and SSTs are around 29C.  There is a 1007mb surface Low embedded in the disturbance.  The forecast is extremely difficult, as is usually the case with minimal steering flow.  Some models keep it basically stationary for the next few days, while others give it a slow nudge off to the north or northeast.  If it remains over water, it certainly has the potential to continue organizing.  However, given the motion (or lack thereof), there is time to monitor it.  The biggest immediate threat is flooding rains in Panama, Costa Rica, and Nicaragua.  In the off-chance this gets named, the next name on the list is Rene.

The season has been an active one, with 16 named storms and 8 hurricanes, 5 of which became major hurricanes (CAT3+).  Although there were no CAT5 storms this year, there was a major hurricane in every month from July through November, which was a first.  In July, Bertha reached 105kts, Gustav reached 130kts in August, Ike reached 125kts in September, Omar reached 110kts in October, and Paloma reached 125kts in November.
If one considers an "average" season based on 1950-2000 climatological values of the number of named storms, hurricanes, and intense hurricanes, as well as the longevities of each, and defines that to be 100% of normal activity, this season was 165% of average activity.  It was similar in total activity to 1998's season.

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