Saturday, May 31, 2014

"Six Key Questions for the 2014 Atlantic Hurricane Season""

From Wunderblog:
The 2014 Atlantic hurricane season is officially underway on Sunday, June 1. What will this year's hurricane season bring? My top six questions for the coming season:

1) When will the first "Invest", tropical depression, and named storm of the 2014 Atlantic hurricane season form? We have a chance of all three of these events occurring in the Gulf of Mexico during the first week of hurricane season, though the models are currently hazy about this. An area of disturbed weather in the Eastern Pacific located a few hundred miles south of Southeast Mexico is forecast to move slowly northwards towards the Gulf of Mexico Sunday through Tuesday. In their 8 am EDT Friday Tropical Weather Outlook, NHC gave this system a 50% chance of developing into a tropical depression or tropical storm by Wednesday. The 06Z Friday run of the GFS model predicts that this disturbance will make landfall in Southeast Mexico on Tuesday, then spread moisture northwards over the Gulf of Mexico late in the week. The model predicts that wind shear will be light to moderate over the Gulf late in the week, potentially allowing the disturbance to spin up into a tropical depression. The 00Z Friday run of the European model has a different solution, predicting that the Eastern Pacific tropical disturbance will remain south of Mexico through Friday.
However, the model suggests that moisture streaming into the Gulf of Mexico late in the week will be capable of spawning an area of low pressure with the potential to develop in the Southern Gulf of Mexico's Bay of Campeche. In any case, residents of Southeast Mexico and Western Guatemala appear at risk to undergo a multi-day period of very heavy rainfall capable of causing flash flooding and dangerous mudslides beginning as early as Monday. This disturbance may cross over Mexico and into the Gulf of Mexico and create the Atlantic's first "Invest" with the potential to develop late in the week, sometime June 5 - 7.

Figure 1. Satellite image taken at 7:45 am EDT Friday May 30, 2014, showing an area of disturbed weather a few hundred miles south of Southeast Mexico. Will this disturbance cross over into the Gulf of Mexico and create the Atlantic's first "Invest" of 2014 late in the week? Image credit: NASA/GSFC.

2) All of the major seasonal hurricane forecasts are calling for a below-average to near-average season, with 9 - 12 named storms, 3 - 6 hurricanes, and 1 - 2 major hurricanes. Hurricane seasons during the active hurricane period 1995 - 2013 averaged 15 named storms, 8 hurricanes, and 4 major hurricanes. Will an El Niño event indeed arrive, bringing reduced Atlantic hurricane activity, allowing the pre-season predictions to redeem themselves after a huge forecast bust in 2013?

3) How will the steering current pattern evolve? El Niño years tend to feature more storms that recurve out to sea and miss land; will this be the case in 2014?...MORE