THREE TROPICAL DISTURBANCES, ONE TO APPROACH GULF THIS WEEKEND… The Atlantic Basin is now quite active with 3 tropical disturbances to monitor. INVEST 97L, located in the central Caribbean Sea, will move into a more favorable environment for tropical storm formation in the western part of the Caribbean Sea (west of Jamaica) this weekend. This tropical disturbance will likely move into the southern Gulf on Saturday or early Sunday. It remains too early to know where the system will ultimately move, but the odds of direct United States impacts are growing. We’re also watching a separate tropical wave several hundred miles east of the Lesser Antilles in the middle of the Atlantic Ocean. This disturbance is on the cusp of becoming a tropical depression this evening. In addition, one thing that has changed since yesterday’s update is that another tropical wave is moving off the African continent that is poised to develop into a potentially long track, Cape Verde-type storm in the days ahead. Below are all of the details.
LEVEL 1 (OUT OF 5) SEVERE WEATHER RISK ON THURSDAY… Outside of the tropics, tomorrow (Thursday) looks to be quite wet across south Alabama and northwest Florida with numerous showers and thunderstorms likely in the afternoon and evening hours. The Storm Prediction Center has placed the entirety of Alabama and northwest Florida in their low-end, Level 1 (out of 5) severe weather risk valid for Thursday. This is because some of the thunderstorms on Thursday may briefly ramp up to severe levels and produce damaging straight line winds. The tornado risk on Thursday remains very low, if not zero in most spots. Any severe thunderstorms that flare up on Thursday will be most likely from 2PM to 8PM. Storms will gradually fade away after sunset, but we may have another round of storms at the immediate coast tomorrow night after 10PM. I’ll have radar updates posted throughout the day in the RedZone Weather app.
97L: TROPICAL WAVE SOUTH OF HISPANIOLA NOW… INVEST 97L, the tropical wave in the Caribbean Sea, is the system that warrants the most concern over the next few days. The National Hurricane Center gives the disturbance an 80% chance of becoming a tropical storm this weekend, once the wave axis reaches the western part of the Caribbean Sea. Right now, visible satellite imagery shows a disorganized mass of showers and thunderstorms located squarely in the middle of the Caribbean Sea, south of Haiti and southeast of Jamaica.
97L: LIKELY TO BECOME TROPICAL STORM THIS WEEKEND… Several ‘ingredients’ will be ripe for the development of a tropical storm once this tropical disturbance moves west of Jamaica. 1) The disturbance will have an uninterrupted flow of moisture from the south, due in part to another, weaker tropical wave axis currently over Venezuela. More moisture will allow the tropical disturbance to ward off drier air, located to the north of the system. 2) Wind shear in the upper-levels of the atmosphere will be more relaxed this weekend over the western Caribbean, allowing thunderstorms to grow and consolidate around a low-level circulation center that will likely develop. 3) Sea surface temperatures in the central and western Caribbean are sky high. Right now, 97L is over a patch of the Caribbean where SSTs are around 84 degrees. The western Caribbean is even warmer, with water temps in the 87-89 degree range. This will act as high octane fuel for the developing storm.
97L: LOCAL IMPACTS IN SW AL & NW FL POSSIBLE… While it is important for me to tell you that we do not know just yet where 97L will go, there is a chance the system will move toward our local area in south Alabama and northwest Florida by midweek of next week, aka one week from today. Obviously smaller scale movement of the system will determine a lot about specific local impacts. There is no way to know where the system will track once it arrives in the Gulf of Mexico just yet. Some models have indicated the system may move into our area or perhaps just to our east into the Florida Panhandle region. Other models suggest more impacts for Texas and Mexico. We note that the reliable ECMWF/Euro model *and* the American-based GFS continue to show a weak, non-developed low pressure area moving into Texas in about a week. The big takeaway is we must continue to monitor this tropical disturbance.
98L: TROPICAL WAVE EAST OF THE ANTILLES… I suspect, based on the satellite appearance of INVEST 98L, that this system will become a tropical storm tonight or tomorrow. Satellite imagery shows a classic mid-level circulation and spin in the center of the tropical wave, indicating tropical storm formation is likely happening right now. The disturbance has isolated and consolidated itself away from the monsoon trough that it was previously embedded in yesterday. IF this system becomes a tropical storm before 97L, it will take the name “Laura.” I expect that to happen in the next 24 hours.
98L: GOOD TRACK CONFIDENCE AT THE MOMENT… Uncertainty is the word for the system in the Caribbean, but it is interesting to note that track guidance for 98L seems a bit more confident. There is good agreement that 98L will develop into a tropical storm and move near or just north of the Lesser Antilles this weekend. Impacts in Puerto Rico and Hispaniola will be possible this weekend into early next week. Unfortunately, most model guidance suggests 98L *might* move toward the Gulf of Mexico in about a week’s time. While that idea is certainly not set in stone just yet, it does serve as yet another reminder that we must be prepared for the peak of hurricane season.
NEW TROPICAL WAVE EMERGING FROM AFRICA (99L SOON)… In addition to the tropical wave in the Caribbean Sea (97L) and the tropical wave in the central Atlantic (98L), the National Hurricane Center is also keeping tabs on a robust tropical wave slated to move off of the African continent by Friday. This disturbance is (quite literally) on the other side of the world and is more of a curiosity at this point. Even if development happens soon, we have a long amount of time to track the system. Early model guidance points to a disturbance that may develop and recurve into the open waters of the Atlantic. From NHC: A large area of showers and thunderstorms, located over Guinea and Sierra-Leone, Africa, is associated with a vigorous tropical wave. Environmental conditions are expected to be conducive for some development of this system while the wave enters the extreme eastern Atlantic on Friday. By early next week, however, conditions are forecast to become less favorable for tropical cyclone formation while it moves west-northwestward at 15 to 20 mph toward the central tropical Atlantic.”
APP ALERTS… Now is the time, long before we get to this severe weather potential, to set up the RedZone Weather app on your smartphone! redzoneweather.com/app is the link where you can download the iOS or Android version of the app. Once you have the app downloaded to your device, be sure to visit the Alerts tab (lower right corner of the app), then tap the large, yellow Alert Settings button to customize the alerts you would like to receive straight from me.
NEXT UPDATE… I will have the next regularly scheduled RZW forecast video posted by 7:15AM on Facebook and in the RedZone Weather app on Thursday with the very latest information concerning all of the tropical disturbances. Have a nice Wednesday evening!