Monday, August 13, 2012

Hurricane Season Forecast Revised From NHC

From the "In Case You Missed It" file:  The National Hurricane Center revised their hurricane forecasts last Thursday (something we didn't report on since we were getting deluged in parts of the region on both Thursday and Friday).

The new projections are a bit higher in overall numbers of storms -- reflected in the faster start the Atlantic basin experienced this year with four tropical cyclones before the end of June.  The new NHC forecast for the Atlantic (in concert with the Climate Prediction Center) is between 12 and 17 named storms, five to eight of which are projected to intensify into hurricanes.  This is an increase from the old forecast of nine to fifteen named storms, four to eight hurricanes, from May.

“We are increasing the likelihood of an above-normal season because storm-conducive wind patterns and warmer-than-normal sea surface temperatures are now in place in the Atlantic,” commented Gerry Bell, Ph.D., lead seasonal hurricane forecaster at the Climate Prediction Center. “These conditions are linked to the ongoing high activity era for Atlantic hurricanes that began in 1995. Also, strong early-season activity is generally indicative of a more active season.”

The reference to above normal is to historical long-term normals (back to the 1850's), which are about 11 tropical storms or stronger. However, since 1995 the average hurricane season has featured 15 named storms, eight of which have become hurricanes. In all reality, the forecast is pretty close to the normals for the active Atlantic pattern.

Through today, we have had six named storms in the Atlantic basin and with the next eight weeks the historical "active" part of the hurricane season I think the possibility of a season that ends up near 15 storms is doable.  However, much of that development will need to take place in the next six weeks or so...El Nino is starting to slowly fire up in the Pacific, which should help to mitigate and slow tropical development after the peak of the hurricane season in September as unfavorable upper level winds start to take over the Atlantic basin's tropical regions.

One of the other "big name" forecasters in the tropical realm, Dr. Grey and Dr. Klotzbach out at Colorado State, have increased their projections to 14 named storms, six of which become hurricanes.  Their April projection called for 10 named storms, which they increased on June 1st to 13 named storms.