The forecast models run with data input this morning are now coming out in regard to the Gulf of Mexico disturbance. They show a situation, as discussed earlier, that’s pretty much the same: confused.

The storm continues to show signs of developing, and the National Hurricane Center believes there’s a 70 percent chance it will become a depression or Tropical Storm Debby within the next two days.

Of the major dynamical models, the GFS has the the Gulf disturbance eventually being pulled to the east-northeast next Tuesday and across the Florida peninsula. So do the hurricane-specific U.S. models, the GFDL and the HWRF.

However the other global models are still forecasting a turn to the west after the Gulf system wobbles northward over the weekend.

The Canadian model brings a rather substantial hurricane to the upper Texas coast by next Thursday morning. I think this model is overcooking the storm’s development, as other forecast models do not envision such explosive intensification.

Also favoring a more westward track are the European model, which brings the storm toward south Texas, and the U.S. Navy’s model, which brings it into northern Mexico.

If you’re wondering, here’s the latest forecast from ImpactWeather, which favors a westward track for the system over the Florida option.

But they’re hedging. “Considering the divergence track paths and times in the model guidance beyond 72 hours, confidence in the forecast track remains low,” their forecast concludes.

I have to agree with that.

WHY ARE THE MODELS SO DIVIDED?

I wanted to provide some context for why the models are so split on what will happen to the Gulf storm. The map below, from Ryan Maue’s excellent site, shows air pressures as well as wind directions at the 500 millibar level of the atmosphere, essentially the middle, where half of the atmosphere is above and half below.

In the image above you’ll see a large white area centered over Oklahoma. That’s the high pressure that’s going to keep us hot and dry this weekend. Highs circulate clockwise, so over the northern Gulf there’s a westward steering flow. Now, over the northeastern United States you can see a low-pressure system, which is rotating counter-clockwise.

The GFS forecast model thinks the rotation of that low will be strong enough such that it will provide a southwesterly steering current, dragging the Gulf low across Florida and into the open Atlantic off the eastern United States.

However, most of the other models foresee the high being more dominant, forcing the storm to the west and blocking a northeast movement.

To find out which models are correct we’re just going to have to wait and see.