Invest 94 update 06041630Z
June 4, 2011
There was a short period of time yesterday in which it appeared that tropical cyclone formation was going to occur sooner rather than later. Late yesterday afternoon, the National Hurricane prepared for this possibility by requesting a late addition to the Plan of the Day for the Hurricane Hunters. The addition scheduled a flight for this afternoon (was subsequently canceled this morning). Statistical intensity guidance suggested that if the area of low pressure was organized like a tropical depression (and it seemed to be getting close), it would be a tropical storm within the next 36 hours.
Since then, however, the old standby phrase “development, if any, will be slow to occur” seems to be the better outlook. Satellite imagery showing thunderstorm activity away from a center of circulation that can be seen clearly makes it evident that the low is not close to being classified as a tropical depression. As such, the statistical intensity forecasts are hypothetical and not particularly reflective of reality.
As of last night, the forecasts from the global models with regard to the low developing were unchanged. Reliable models show the low persisting, but not developing into a tropical cyclone. The two dynamic models specialized for hurricanes GFDL and HWRF aren’t particularly useful when a tropical cyclone is in an embryonic stage. Yesterday evening’s HWRF run was a bit excitable (as was the one that followed it), showing near immediate development into a tropical storm:
As conditions stand at the moment, the assertion that the only sound forecast is for a near stationary system bringing rain to Jamaica and Hispanola remains valid. The are recon flights scheduled to check out Invest 94 tomorrow; though if it ‘s clear that the low is not near tropical depression status, they will be canceled as today’s was.
If events cause me to have anything substantial to say, I’ll have another post today. Otherwise, observations, if any, will be restricted to Twitter.