TROPICAL STORMS LAURA AND MARCO TO BOTH BE IN GULF BY MONDAY… Tropical Storm Laura continues to rapidly move west near Puerto Rico while Tropical Storm Marco continues its trek northwest across the western Caribbean Sea. Marco will likely cross into the southern Gulf of Mexico later tonight, while Laura will arrive into the southeastern Gulf on Monday evening. While Marco is moving toward the Texas or western Louisiana coast and will probably be a weaker system in 4-5 days, Laura will probably be strengthening in 4-5 days over the warm waters of the central Gulf of Mexico. The official forecast from the National Hurricane Center shifted a bit farther west throughout the day on Friday. NHC now calls for Laura to be a hurricane Tuesday night before potentially approaching the Louisiana coastline on Wednesday. We note that the cone of uncertainty extends from the Texas-Louisiana border eastward to Navarre, Florida. That means that it is still too early to pinpoint exactly where the center of circulation will move onshore. Impacts will extend well beyond the center, reaching potentially 200+ miles away in some cases. Locally on this Saturday, isolated thunderstorms will likely pop up, but we are not expecting widespread severe weather issues. Let’s look at all of your Saturday morning forecast details…
POTENTIAL LOCAL IMPACTS DUE TO LAURA IN SOUTH ALABAMA & NW FLORIDA… This has not changed since last evening. I suspect we’ll be able to get a bit more specific later this evening. Local impacts will be possible Tuesday, Wednesday, and early Thursday from what is currently Tropical Storm Laura. Forecast confidence remains unusually low, as we don’t know just yet how much land interaction will degrade the storm over the next few days. While local impacts will be possible, it is too early to suggest specifics for any city or town across our region. At a minimum, I expect gusty winds at the immediate coast and high surf & rip currents at local beaches. Depending on the exact future track of Laura, potential local impacts may have to be adjusted significantly. Direct local impacts from TD14/Marco appear unlikely.
TIMING FOR LOCAL IMPACTS IN SOUTH ALABAMA & NW FLORIDA… IF (and that is a massive IF) we have impacts in south Alabama and northwest Florida due to Tropical Storm Laura, there is good evidence in the model guidance to suggest Wednesday would be our “bad weather” day due to Laura. Tuesday evening through Thursday morning is the 36 hour window when impacts from Laura would be most likely locally, IF we have impacts in our region. The future track will determine the magnitude of potential local impacts.
FUJIWHARA INTERACTION UNLIKELY – BUT STILL A POSSIBILITY… The world has been fascinated over the last few days by the fact that there may be two hurricanes in the Gulf of Mexico early next week. That possibility seems diminished as Marco is currently not forecast to become a hurricane. What seems likely, however, is that Laura and Marco may exist simultaneously as two, distinct tropical storms in the Gulf on Monday into Tuesday. That event has happened twice before in recorded history, once in 1933 with the other instance in 1959. While the current forecasts do not indicate a “Fujiwhara effect interaction” between Tropical Storms Laura and Marco, that doesn’t mean the chances are zero. IF Laura (as a hurricane midweek) moves farther west than the current forecast track, there is a chance Laura’s circulation may push Marco to the south once it is near the Texas coast. There also is a chance Marco will be so weak that the system dissipates with lingering moisture being absorbed by Laura. Again, those are hypotheticals at this point that likely will never happen. It certainly is interesting to think there even is a small possibility of a Fujiwhara interaction in the Gulf of Mexico. I never expected to see something like that in my lifetime. The effect is more commonly observed in the Pacific, where typhoons have virtually unlimited space and ocean to work with. I cannot imagine quantifying how rare it would be to get a true Fujiwhara interaction in the Gulf of Mexico. Not likely to happen, but still a remote possibility.
TROPICAL STORM MARCO NEAR THE YUCATAN TONIGHT… Tropical Storm Marco will make its closest approach to the Yucatan Peninsula of Mexico this evening. We note that a Tropical Storm Warning is in effect from Punta Herrero to Dzilam in Mexico, including Cancun and Cozumel. The forecast track for Marco has shifted a bit to the right (east) and there is a chance the system may never make landfall in the Yucatan and actually remain over water in the Yucatan Channel between the Caribbean Sea and Gulf of Mexico. Marco has a very limited window today, tonight, into early Sunday to strengthen before the system gets absolutely pounded by upper-level atmospheric shear Monday into Tuesday. That should keep the system’s strength in check as it approaches the Texas coast on Tuesday.
TEXAS IMPACTS LIKELY BECAUSE OF MARCO… The cone of uncertainty for Tropical Storm Marco continues to shift around a bit, but the general consensus remains that Marco is likely headed for the Texas or western Louisiana coastline. Impacts may begin in parts of Texas and southwestern Louisiana as early as Monday afternoon. The National Hurricane Center is currently forecasting landfall between Corpus Christi, Texas and Morgan City, Louisiana as a weakening tropical storm some time on Tuesday. Landfall seems most likely to happen around Houston and Galveston, but there is still a large swath of coastline included in the cone of uncertainty. It is too early to rule out a Louisiana landfall.
POP-UP STORMS TODAY AND SUNDAY… Storms will likely be more isolated this afternoon into this evening compared with the last few days, meaning storms should have plenty of space between them. We’ll call it a 40% chance of showers and storms this afternoon into this evening. High temperatures will be in the upper-80s. Coverage of storms will increase on Sunday with most of the storms likely happening again in the P.M. hours.
APP ALERTS… If you haven’t already downloaded the RedZone Weather app, now is a great time to do that. redzoneweather.com/app is the link to the free download. Once you have the RZW app installed on your iOS or Android device, be sure to visit the Alerts tab to turn on the specific notifications you’d like to receive. All notifications are handcrafted by me. No automation and we promise not to bug you!
NEXT UPDATE… I will have another detailed update discussing Tropical Storm Laura and Tropical Storm Marco posted later this evening. I also will have shorter form updates posted throughout the day into this evening in the RedZone Weather app.
Have a great Saturday!