Thoughts on Bill

As fast as the tropics exploded, they have pretty much settled down as quickly -- with one notable exception. Tropical Storm Claudette made landfall late last night as a weak tropical storm and is currently located just near the Golden Triangle area in Mississippi. Ana has once again been downgraded to a remnant low pressure center as it is just south of Hispaniola. It's too early to give up on Ana just yet as it should emerge into the eastern Gulf of Mexico later in the week. As we saw with Claudette, the environment in the Gulf is certainly supportive of quick intensification, so residents along the northern Gulf Coast should still keep an eye on the storm formerly known as Ana.


The big tropical news continues to be Hurricane Bill which is located about 950 miles east of the Lesser Antilles. The satellite presentation has begun to look extremely impressive this afternoon with solid banding, a symmetrical appearance, well-established outflow, and the development of what appears to be an eye. 85 GHz microwave imagery also suggests deep convection is beginning to surround the center of the hurricane. The good news is that Bill shouldn't threaten any land masses within the next several days, and that's a good thing because it will likely become a major hurricane tomorrow. The dynamic environment remains very favorable for some additional intensification, and the thermodynamic will become very favorable once Bill moves west of 50 degrees West early tomorrow morning. If it's not a major hurricane by that point, expect it to quickly attain that status and likely Category 4 strength within the next few days given the expected light shear, moist ambient air, and favorable thermodynamic environment.

The largest question remains the future track of Bill. Bill has been steered for the last few days by a deep layer subtropical ridge. A weakness in the ridge centered near 30 deg N and 47 deg W should allow Bill to turn slightly more north of west over the next couple of days. By Wednesday, the subtropical ridge re-strengthens but will quickly be pushed eastward by a trough digging into the Midwest on Thursday. As it does so, Bill should begin to move more northwest and then north by Saturday as it will be sandwiched between the trough to its west and ridge to its east. Where exactly this north turn begins will be critical as to whether the United States gets hit or whether the Canadian Maritimes gets hit.

Dynamical model guidance has shifted westward today, and it will be interesting to see if this is indeed a trend. I still prefer the consistent Canadian model, which does bring Bill very close to Maine by Sunday. I'm leaning slightly east of it's track, but based on the current model track, the New England coastal areas could experience tropical storm force conditions late this weekend. I don't want to completely write off the threat that the U.S. gets hit, but I think New England would be the most likely area to experience landfall.