Tropical Update 9 AM EDT Thursday, May 24, 2018 Invest Area 90L (80%) This update is intended for government and emergency response officials, and is provided for informational and situational awareness purposes only. Forecast conditions are subject to change based on a variety of environmental factors. For additional information, or for any life safety concerns with an active weather event please contact your County Emergency Management or Public Safety Office, local National Weather Service forecast office or visit the National Hurricane Center website at A disturbance near the Yucatan Peninsula will drift northward this weekend into the Gulf of Mexico. There remains some uncertainty with the track and intensity of the system, but will still result in a wet pattern continuing to affect Florida for the next several days. Chance of Development within 48 hours = 40% Chance of Development Saturday-Tuesday = 80% Caribbean/Gulf Satellite Image Thunderstorm activity has increased, but is still displaced to the east of the center. Once the low moves into the Gulf of Mexico, additional development is likely. Steering Currents Steering currents near 90L remain very weak, thus a continued slow northward movement is expected for the next several days. Forecast Weather Map – This Weekend 90L will slowly move northward towards the central Gulf Coast through Memorial Day, but showers and storms will spread well to the east of the center and affect much of Florida. Showers and storms may begin to affect South Florida Friday morning and spread northward into North and Central Florida throughout the day on Saturday. Widespread showers and storms will affect all of Florida Sunday. Showers and storms will linger through Monday for much of the state, with additional lingering storms activity expected along the Florida Gulf Coast on Tuesday. Current Wind Shear (shaded) and Shear Tendency (lines) Moderate to high wind shear in the Gulf will initially limit intensification, but shear is now expected to decrease by Sunday, allowing for a better chance of intensification as it approaches the northern Gulf Coast. Observed Rainfall Over Past 7 Days All of Florida has had well above normal rainfall over the past 7-10 days. This results in saturated grounds that will reduce the amount of time and rain needed to create flood conditions. Above Normal Flow Normal Flow Below Normal Flow Many West Central Florida and some Panhandle rivers are now at above normal flow, meaning additional rainfall may cause flooding issues. Forecast Total Rainfall Accumulations for next 2 Days Soggy conditions will continue this week with rain amounts of 1-3” over the next 2 days. Forecast Total Rainfall Accumulations The rain from 90L will begin to affect South Florida on Friday into Saturday and spread northward through the weekend. With the possibility of this system stalling over the Southeast U.S., additional rainfall may continue into the middle of next week. Saturday Sunday-Monday Forecast Total Rainfall Accumulations for next 7 Days EXACT RAINFALL AMOUNTS WILL DEPEND ON THE STRUCTURE AND TRACK OF 90L, WHICH COULD BE HIGHER THAN WHAT IS SHOWN. At this time, widespread average rainfall amounts of 3-6” inches are possible statewide, with isolated higher totals of 7 to 13 inches possible over portions of the Panhandle and Southeast Florida. This should result in street flooding and river flooding, especially in areas where several storms repeatedly move over the same area. • Since soils are already saturated, any additional heavy rain (generally 3-4” in less than 3 hours) will cause flash flooding issues. • Lower amounts, or 3-6” over a longer time period can still cause flooding of roads and low-lying areas. • Note: hydrograph forecasts only account for anticipated rainfall over the next 48 hours. Although a recession is forecast, additional rises this weekend are likely. In addition to the flash flooding potential, minor to moderate flooding on area rivers will be possible, but this will ultimately be dependent on where the heaviest rain falls. The areas for concern are currently in West Central Florida, the Florida Panhandle, and the Santa Fe River basin and Paynes Prairie State Park. Summary • A broad surface low (Invest 90L) centered over the Yucatan Peninsula is gradually getting better organized. • Continued development is expected once the system moves into the southern Gulf of Mexico by Saturday morning, and environmental conditions are forecast to become more conducive for development in the central and northern Gulf of Mexico over the weekend. • As a result, the National Hurricane Center is now predicting a 40% (medium) chance of 90L becoming a tropical depression or storm within the next 48 hours, and an 80% (high) chance of becoming a tropical cyclone within the next 3-5 days. • Although computer models are getting into better agreement, there is still a fair amount of uncertainty with regard to the track, intensity and timing of the system. • The low pressure system should reach the northern Gulf coast region on Sunday or Monday (a day later than previously forecast) and then linger over the region into the early part of next week, increasing the rainfall totals and threat for flooding. • If named, the first name on the 2018 Atlantic Storm name list is Alberto. Florida Outlook: • Regardless of track or intensity, this system will result in a multi-day widespread rainfall event that may impact a large portion of Florida, mainly Friday-Sunday across South Florida and Saturday through at least next Wednesday for North Florida and portions of Central Florida. • There are currently no watches or warnings, but Flood Watches, Flash Flood Watches, Coastal Flood Watches and High Surf Advisories may be issued by Friday. • Widespread rainfall amounts of 3-6” are expected statewide, with locally higher amounts of 7-12+” possible, especially for the Florida Panhandle and possibly West Coast of Florida. • River flooding will also be a concern for portions of the state, especially in West Central Florida, North-Central Florida and the Florida Panhandle/Big Bend. • Increased wave heights are also expected along the Panhandle and East Coast and will lead to a high risk of rip currents for the holiday weekend. • Any other possible impacts late this week through early next week (wind, tornadoes, and surge) will depend heavily on how this system evolves and more information will be available in the coming days. Another briefing packet will be issued this afternoon. For more information on this system visit the NHC website at Tropical Update Created by: Amy Godsey, Chief State Meteorologist This email address is being protected from spambots. You need JavaScript enabled to view it. State Meteorological Support Unit Florida Division of Emergency Management Users wishing to subscribe (approval pending) to this distribution list, register at _Tropics. Other reports available for subscription are available at
For questions about Fair Housing, Equal Employment Opportunities and/or Section 504 procedures regarding the Americans with Disabilities Act, please contact Joan O'Connor, Town Clerk by telephone at 386-649-4902, who serves as the Coordinator for Fair Housing, the Equal Employment Opportunity and the Section 504/ Americans with Disabilities Act.

Contact Us

  • 1775 US Hwy 17 South
  • P.O. Box 518
    Pomona Park, FL 32181
  • 386-649-4902
  • Email US