ISOLATED SEVERE STORMS POSSIBLE TODAY; NEW TROPICAL DEPRESSION 13… There is a low-end risk of a few strong to severe thunderstorms today (Thursday) across Alabama and northwest Florida today. Gusty winds, capable of knocking down a few trees, will be the main concern. Most of the storms will happen in the afternoon and evening hours. The overall tornado risk today remains very low locally. Our focus continues to be on the developing tropical disturbances in the Atlantic and Caribbean. The National Hurricane Center started issuing advisories late last evening on Tropical Depression 13, located in the central Atlantic Ocean. This system will rapidly move west-northwest in the days ahead as it gradually strengthens. TD13 may be a tropical storm or even a hurricane by the time it reaches areas near The Bahamas, Cuba, South Florida, and the Florida Straits by Sunday into Monday. As if one tropical threat wasn’t enough, we’re also monitoring a tropical wave in the central Caribbean Sea (INVEST 97L). There is a chance 97L could strengthen this weekend as it, also, moves into the southern Gulf of Mexico. Let’s look at all of your forecast details on this very busy Thursday.
LOW-END SEVERE WEATHER RISK TODAY ACROSS ENTIRE AREA… The Storm Prediction Center maintains a low-end, Level 1 (out of 5) marginal severe weather risk for the entirety of Alabama and northwest Florida. This includes all of south Alabama and northwest Florida. This low-end risk is mainly in place because of the risk of a few stronger to marginally severe thunderstorms this afternoon into this evening. These storms will be capable of producing gusty winds that could knock down a few trees. Torrential downpours of rain and cloud-to-ground lightning will also be concerns in the thunderstorms today. The overall tornado risk remains very low, if not zero in most spots. I will have radar updates posted in the RZW app as needed throughout the day and into this evening. High temperatures this afternoon will be in the upper-80s.
SCATTERED TO NUMEROUS STORMS LIKELY FRIDAY AND SATURDAY… Rain chances will remain elevated both Friday and Saturday as a strong southerly flow from the Gulf of Mexico continues to usher in plenty of moisture for storms to “feed on” each day. Most of the showers and thunderstorms on Friday and Saturday will happen in the P.M. hours. Highs will be in the mid- to upper-80s with morning lows around 70 degrees.
TROPICAL DEPRESSION 13 IN THE ATLANTIC RAPIDLY MOVING NORTHWEST… The National Hurricane Center kicked off advisories on Tropical Depression 13, formerly known as INVEST 98L, last night at 10PM CDT. TD13 remains in the formative stages today. There is a high chance this will become a tropical storm later today, tonight, or on Friday. If/when it does, it will take the name Laura (or Marco if 97L in the Caribbean happened to form first, which seems less likely at this point). TD13 will approach the northern Lesser Antilles tomorrow into Saturday, probably passing near or just to the north of the islands as a tropical storm. Interests in the Lesser Antilles, the U.S. and British Virgin Islands, Puerto Rico, Haiti, the Dominican Republic, the Turks & Caicos, The Bahamas, and Cuba should closely monitor the progress of this developing tropical depression.
TD13 LIKELY TO BE NEAR SOUTH FLORIDA SUNDAY… The general, future track of Tropical Depression 13 is pretty confident, BUT what is not confident is the future strength. IF TD13 takes a more southerly track, it will be significantly hindered by the Greater Antilles (Puerto Rico, Hispaniola, and Cuba). That could allow a weaker system to move into the Gulf of Mexico by Sunday into Monday. On the contrary, if TD13 takes more of a northerly track, there could be bigger issues for South Florida Sunday into Monday. The system may be an approaching hurricane. Unlike Hurricane Isaias a few weeks ago, model guidance has been firmly suggesting TD13 will move into the Gulf of Mexico early next week, potentially as a strong tropical storm or hurricane. I am certain that wild speculation and fear mongers will post the model guidance showing Gulf Coast impacts, but again, we all need to take a step back (I’m speaking to myself too!) and remember that NO ONE knows exactly where this system will end up. No one. Gulf Coast impacts are possible as we go into next week. Unfortunately, that’s the best statement I can give on this right now. I’ll let you know more when I know more. Don’t get caught up on any one run from any one model. They will change drastically in the days ahead.
INVEST 97L MOVING TOWARD WESTERN CARIBBEAN SEA… The tropical wave we’ve been tracking over the last few days in the Caribbean Sea continues to be somewhat disorganized, which is a good thing. This, however, was somewhat expected as the disturbance is MORE likely to develop Friday through Sunday when it is located in the western Caribbean Sea closer to the Yucatan Peninsula of Mexico. NHC continues to give this disturbance an 80% chance of developing into a tropical storm over the next 5 days.
INVEST 97L MORE LIKELY TO DEVELOP THIS WEEKEND… Several ‘ingredients’ will be ripe for the development of a tropical storm once INVEST 97L 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 part of the Caribbean Sea 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.
WHAT HAPPENS TO 97L AFTER THE WEEKEND… It truly is anyone’s guess at this point. Forecast confidence in the overall future track of Tropical Depression 13 is (and has been) much more consistent and predictable in the short- and medium-term. Model guidance continues to be “all over the board” this morning. We just do not have a good grip of the specifics that could steer INVEST 97L. Some model ensembles take the system on a more northerly route toward the Florida Peninsula, while some bring the system north toward the Florida Panhandle. Other models move the system toward Louisiana, Texas, or Mexico. Confidence in the future track of 97L will probably become higher tomorrow (Friday) into Saturday. Stay tuned!
TROPICAL WAVE NEAR AFRICAN COAST… NHC says there is a 40% chance that a tropical wave currently situated over western Africa will emerge in the eastern Atlantic and quickly become a tropical storm as the tropical wave moves westward. Early model indications point to this system recurving into the open waters of the Atlantic. We’ll keep you posted, but this system is halfway around the world right now. TD13 and 97L clearly warrant our attention more than this wave at the moment.
REVIEW HURRICANE PLAN TODAY… I do not say this strictly because we have two potential tropical threats over the next 7-10 days, I say this because it is what we ALL should do as we approach the peak of the Atlantic Hurricane Season. Hopefully our local area won’t have any issues, but NOW is the time (before we get to any imminent tropical threat) to review your hurricane safety plan. If you’re in a coastal area, do you know your evacuation route and where you would go if a strong hurricane approached our area? If you’re inland, do you have a hurricane prep kit and supplies ready? I’m not talking about supplies you need to buy right before a hurricane hits, I’m talking about the things we all should have in place WELL in advance of any storm: Batteries, first aid kits, non-perishable food items, plenty of prescription drugs, cell phone chargers, etc. Now is a great time to review your emergency plan and make sure you have the things we should have every, single day of hurricane season. More info here: https://www.ready.gov/hurricanes
APP ALERTS… Now is the time, long before we get to this tropical 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 post another detailed update later this evening here on Facebook and in the RedZone Weather app with the very latest on TD13 (which may be Tropical Storm Laura by then) and INVEST 97L. In the meantime, be sure to catch my updates throughout the day in the RedZone Weather app. I’ll have radar updates posted as needed today. Have a great Thursday!