Jacksonville could see morning showers, with temperatures in the low to mid-70s, but the quiet morning is expected to give way to a muggy afternoon of showers and thunderstorms. Rain chances rise around 11 a.m., with the best opportunity for storms from noon through 5 p.m. The high should reach about 88 degrees before temperatures ease through the afternoon.
Tuesday storms could bring brief heavy rain
Most of Tuesday should remain partly to mostly sunny as northeast winds increase to around 12 mph. Storms are not expected to be widespread, but slow-moving cells could produce brief heavy downpours, gusty outflows and localized flooding, especially inland. No watches or warnings were listed for Jacksonville Tuesday morning, though drivers should allow extra time for sudden rainfall on roads that collect water.
The flooding concern is local rather than uniform across the city. The City of Jacksonville’s Public Works division says Duval County faces coastal, inland and river flooding, with the most common flooding occurring during the June-through-November rainy season. That broad vulnerability does not mean every neighborhood will flood Tuesday, and the forecast does not establish where any flooding will occur.
Wednesday turns wetter and windier
Showers and thunderstorms become more likely Wednesday, with a 60% rain chance and a high near 87 degrees. Rain could continue from morning into afternoon as winds strengthen. Near the coast, northeast winds could gust around 26 mph overnight.
Stronger onshore winds are expected to increase the rip-current risk at area beaches from Wednesday evening into late week. Beach conditions and exact storm coverage can vary considerably over short distances, so the current forecast should not be read as a guarantee that every beach or inland location will see the same impacts.
Coastal water concerns build Thursday
Thursday looks cooler, with a high near 83 degrees and a lower chance of showers and thunderstorms. Along the Northeast Florida coast, north-northeast winds could become much stronger, with frequent gusts of 35 to 40 mph possible. Minor coastal flooding could begin around Thursday evening’s high tide and continue through the weekend. Flooding concerns may also spread into the St. Johns River basin starting Friday.
High tide matters because water-level impacts depend on timing as well as wind. During the separate Hurricane Nicole event, the National Weather Service Jacksonville reported that the south bank of the St. Johns River flooded and inundated Southampton Road around high tide. Nicole was a much different, hurricane-related situation, so it is a historical example of why tide timing matters—not evidence that the current forecast will produce the same outcome.
For current travel safety, JaxReady warns that six inches of moving water can knock over an adult and urges residents not to drive through flooded roads. Whether Tuesday’s storms or the later coastal-water concerns produce meaningful travel impacts remains dependent on the exact storm track, rainfall rates, wind and tide levels.
How unusual is the temperature pattern?
The heat ahead of the front is modestly above Jacksonville’s late-September benchmark. The National Weather Service Jacksonville climate report lists 1991-2020 normal temperatures for September 22 at 86 degrees for the high and 70 degrees for the low. Tuesday and Wednesday are forecast to run a little warmer during the day, while Friday and Saturday should be cooler, with overnight lows near 67 degrees.
Rainfall totals also show why a wet-season forecast does not automatically describe persistently wet conditions. The same climate report listed 3.52 inches of rain month to date through September 21, compared with a 5.31-inch normal—a deficit of 1.79 inches. That comparison describes rainfall through the reporting date, not a prediction that the coming storms will erase the deficit.
A cooler, drier weekend follows
Conditions should turn noticeably cooler and drier by Friday, with a high near 81 degrees and an overnight low around 67. Saturday should be sunny with a high near 82, followed by another mostly clear night near 67. Sunday stays mostly sunny and reaches about 84 degrees, with Monday warming slightly to around 85.
The practical sequence is a quick one: muggy storms Tuesday and Wednesday, stronger coastal winds and possible minor flooding concerns Thursday into the weekend, then a cooler and more comfortable setup for outdoor plans. The forecast supports preparing for abrupt rain and changing beach conditions, while the exact location and severity of any flooding remain uncertain.
