Watching 96L; How do you solve a problem like Maria? Easy - throw a trough at her

Please note that these tidbits do NOT reflect the official forecasts of the National Hurricane Center, and should not be taken as such. While tropical cyclones exist in the Atlantic, the official NHC forecasts will be posted in the lower part of this blog. Please refer to those when making decisions, and heed the advisories and evacuation statements of your local National Weather Service Office. If you can, playing the video in HD makes it much easier to see things. The video will play in low quality by default. If HD quality isn't available, then it will be in a few minutes. Let me know if you have problems with the video, and please feel free to ask me any questions regarding what I talk about in these tidbits, or about the weather in general. You can post in either of my blogs or on Youtube. I will do my best to answer. Thanks for stopping by! Find me on Youtube Find me on Facebook (also on Twitter)

Hurricane Katia continues to weaken and will pass on the most harmless path possible, right between Cape Hatteras and Bermuda, and then well south of the Canadian Maritimes on its way northeastward. Invest 96L is the most immediate concern for the U.S., sitting in the southern Bay of Campeche. This system may try to develop into a weak tropical storm over the course of the next few days, but it is unlikely to get very strong due to extremely dry air to its northwest, caused by upper convergence on the back side of ex-Lee's upper trough. This trough is also imparting southwesterly shear on the Gulf of Mexico, which will also limit 96L's intensification. The air is so cold and dry that you can actually see small cumulus cloud streets north of 96L due to cool air moving over warm water, similar to what you would see in the winter, which is quite amazing for the first week of September. 96L will likely move northward slowly towards the weakness from ex-Lee's trough, and may eventually approach the north gulf coast. A hook to the left into Mexico is also possible if the trough tries to leave 96L behind, especially if it remains a weak system. We will be hoping for such a hook to occur near the Mexico/Texas border so that south Texas might get some rain, but with such weak steering currents it is hard to know for sure if a left hook will occur. Now, we must figure out how to solve a problem like Maria. Tropical Storm Maria is 2-3 days from impacting the northern Leeward Antilles Islands and Puerto Rico. Maria looks decent but nothing like a rapidly strengthening storm, and there are outflow boundaries to the southwest of her circulation, indicating that she is struggling with some dry air. The current downward MJO pulse is likely contributing to sinking motion over the central Atlantic, and this may be one reason why none of the models are strengthening Maria before reaching the islands. Due to these conditions ahead of her, Maria will likely continue to struggle with dry air and may not even be able to become a hurricane before reaching the islands, though it's not impossible that she could. I would be prepared regardless in the leeward islands, and since Irene just recently came through, hopefully preparations will go quickly there. Maria should then start curving to the northwest, likely missing the Bahamas. I'm going to go out on a limb and say that I think Maria is likely to miss the United States entirely. Solving a problem like Maria is easy. Just throw a trough at her. The upper trough associated with ex-Lee will be stuck over the central U.S. for the next 5 days or so, and the only way it's going to escape is if it gets rescued by a big trough from Canada. Such a trough should come down in 5-7 days and phase with Lee's old trough over the eastern U.S. before taking it out. This means that a big trough will have to be in place over the eastern U.S. at some point during the next 6-10 days. As a result, Maria should be recurved out to sea between Cape Hatteras and Bermuda by this trough. The only two ways she could hit the U.S. in this pattern are either to pass into the heart of the Caribbean instead of north of it, or to wait 7-8 days before crossing 70W. Neither of these possibilities seems likely right now. While it is not impossible for Maria to be a problem for the U.S., I think it is more likely that she misses. The next real problem may come after Maria in the northwestern Caribbean, southern Gulf of Mexico, or Bahamas area, because everything is cooling down north of this region. The eastern U.S. is under a cold spell right now, and storms like Irene, Katia, and Maria are cooling the waters north and east of the Bahamas. All of this acts to force convergence and upward motion in the Caribbean, which, combined with a quiet eastern Pacific, supports activity flaring up in there between September 15th and 25th. We shall see what happens! NHC Official Forecast for Tropical Storm Maria: Tropical Storm Maria Model Track Forecasts: Caribbean/East Pacific Visible/IR2 Satellite (click image for loop): Central Atlantic Visible/IR2 Satellite (click image for loop): Atlantic Tropical Surface Analysis: 200mb Vertical Velocity Potential (green areas represent upward motion associated with the MJO):