There are no threat areas in the tropical Atlantic to discuss, and none of the computer models are forecasting tropical storm formation over the coming week. However, there is there a major development to report--it appears likely that a major shift in the weather pattern will occur in late July across the Northern Hemisphere. If the GFS model is correct, the trough of low pressure that has been consistently in place over the Eastern U.S. will finally move off, to be replaced by a ridge of high pressure (Figure 1).
This would bring a hurricane steering pattern much like we saw in 2004 and 2005, with increased risk for the Gulf of Mexico and reduced risk for the U.S. East Coast from the Carolinas northward. The GFS model has been inconsistent in its prediction of the timing of this shift, but has been persistent enough about it that I'm forecasting a 70% likelihood of this major pattern shift occurring by the end of July. Such a shift would bring the western U.S. some relief from the current heat wave, and bring high heat and air pollution problems to the Midwest and East Coast. How long such a shift might last is impossible to predict--it could last for a week, or could remain in place for the remainder of hurricane season. I'll have an updated forecast on this pattern shift Monday, when I issue my bi-weekly hurricane outlook
Jeff Masters Complete blog here
Updated Dr.Masters Blog 7/14/07...
The long-range GFS model continues to forecast that the persistent trough of low pressure that has been present over the Eastern U.S. the past two months will finally move off, to be replaced by a ridge of high pressure by late July. This would bring a hurricane steering pattern much like we saw in 2004 and 2005, with increased risk for the Gulf of Mexico and reduced risk for the U.S. East Coast from the Carolinas northward. The east coast of Florida would remain at normal to above normal risk.
