Good news for Houston and Texas is that Tropical Storm Debby is not expected to make landfall here…for the moment. It’s hard to understand why there is such difficulty in tracking this storm but two forecasters that I have high regard for, Tim Heller, Chief Meteorologist for Houston’s ABC Owned and Operated KTRK-TV and Eric Berger, Science Writer for the Houston Chronicle are really trying to make sense of Debby. Heller writes in his blog on KTRK.COM that “Tropical Storm Debby continues to inch northward. As of 2 PM, the center of the storm appears on satellite to be about 140 miles south/southwest of Panama City, Florida.  The storm is moving northeast at only 5 mph.” “Wind shear from the southwest continues to tear apart the structure of the storm, displaying most of the rain to the north and east. Water temperatures are warm in the northern Gulf, however, the longer Debby stays over the same general area, the less likely it will intensify due to the upwelling of cooler water from below the surface.”

Berger writes for the Chronicle that “over the course of two successive runs the forecast models have simultaneously shifted markedly away from a Texas landfall for Tropical Storm Debby, while coming into significantly better agreement. And the consensus is northern Gulf coast, probably somewhere along the Florida panhandle on Tuesday or Wednesday. The latest run of the European modelis emblematic of the expected forecast track.” After Tuesday the storm could still make a westward turn, which the models were forecasting Saturday, but it would be over land at that time, and the storm would not track all the way to Texas. It’s going to be a wet time in the Florida Panhandle. Heavy squalls are already affecting the area, and rain totals could reach 10-20 inches between now and Wednesday.

So…hang on Florida and breathe a little easier Texas but why has Debby been so difficult to track? Tim Heller explains that “tracking tropical cyclones isn’t usually this difficult. The forecast models usually display a clear tendency by this stage of development.  But Debby is developing between a trough of low pressure to the northeast and high pressure to the northwest and the influence of these two features continues to fluctuate. Since Debby is moving so slowly, over ten inches of rain will fall along the Gulf Coast the next few days.” Steering currents for Debby remain weak which means the forecast track will likely change again.  The models are updated every six hours. The forecast track is adjusted every three hours.

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