Jacksonville is starting Wednesday, August 19, with mostly clear skies and temperatures around 80 degrees, but dangerous heat is building quickly. A Heat Advisory will be in effect from 11 a.m. to 8 p.m., with heat index values reaching as high as 112 degrees before thunderstorms move in later today.
Dangerous Heat Before Afternoon Storms
Temperatures are expected to climb to near 97 degrees, with the heat index reaching around 110 as mostly sunny skies hold through early afternoon. Showers and thunderstorms become likely after 3 p.m., with a 60% chance of rain and possible rainfall totals between a tenth and a quarter of an inch.
Storms Could Bring Sudden Wind And Flooding
The National Weather Service in Jacksonville says stronger storms could produce frequent lightning, torrential downpours and wind gusts of 40 to 60 mph. Storms may become more concentrated near the Interstate 10 and U.S. 301 corridors around sunset, with localized flooding possible in urban and flood-prone areas.
For drivers, the biggest shift may come late in the afternoon, when a hot and bright commute can turn into a sudden downpour. Outdoor workers and anyone planning strenuous activities should try to finish early, keep water nearby and have a shelter plan before storms develop.
Hot Again Thursday With Stormier Weather Friday
Wednesday night will stay muggy, with a low near 77 degrees and a chance of showers and thunderstorms before 11 p.m. Thursday will again reach near 97 degrees, with heat index values up to 107 and another round of storms possible after 4 p.m.
Friday brings a slightly lower high near 95 degrees, but thunderstorms are likely after 2 p.m. The weekend remains hot, with highs near 93 on Saturday and Sunday and afternoon or evening storm chances around 50% to 60%.
Heat Advisory Safety Tips
The weather service recommends drinking plenty of fluids, staying in air conditioning when possible and limiting time in direct sun. Wear lightweight clothing, take frequent breaks in shade or air conditioning, and check on relatives and neighbors who may be vulnerable to the heat.
Anyone showing signs of heat exhaustion should be moved to a cool location and given immediate attention. Heat stroke is an emergency, so call 911 if symptoms become severe.
