90L comes close to being the season's first named storm

The large extratropical storm (90L) that has been pounding Florida, the Bahamas, and Haiti this week with heavy rain and high surf has moved ashore over Mississippi. Last night and this morning, the storm put on an impressive burst of heavy thunderstorm activity and came close to becoming a subtropical or tropical depression. Winds at the Fort Morgan, AL station were 44 mph, gusting to 52 mph, and winds at Dauphin Island, Alabama coastal station were sustained at 39 mph, gusting to 48 mph at between 8am and 10am EDT this morning. While these winds were in excess of the 39 mph threshold of tropical storm force, both measurements were taken at elevations higher than the international wind measurement standard of ten meters, so the top measured winds of 90L were actually slightly less than tropical storm force. Had 90L spent another six hours over water, it very likely would have been declared a tropical/subtropical depression/storm.

The circulation around 90L continues to mean rain for Florida, but the rains will be lessening today. Rainfall amounts as high as 28 inches were measured this week in Northern Florida at Brunnell. Rainfall amounts of 2 - 3 inches have accumulated along the Alabama, Mississippi, and Florida Panhandle coasts from 90L so far (Figure 1).


Figure 1. Estimated rainfall from the Mobile, AL radar.

There are no other threat areas in the Atlantic to discuss today, so have a great weekend, and I'll have a new blog post by Tuesday.

Jeff Masters