The week ahead: Ridging builds in, turning air temperatures up and storms down
High pressure will ridge into the area for much of the new week ahead, sending air temperatures up and thunderstorm chances down before weakening into the weekend, bringing back a better chance of afternoon and evening showers and thunderstorms.
Monday will start out with one more day of decent afternoon and evening thunderstorm chances. We start the day in the mid-to-upper 70s and warm to the low 90s before thunderstorms initiate. A nearby front combined with the inland-moving seabreeze should help provide decent storm coverage across the area, so be ready for the potential for a soggy Monday evening commute. Heavy rain and frequent lightning will be the main concerns.
From there, the ridge begins to build across the area. West to northwest flow aloft keeps the seabreeze pinned closer to the coast, and this will help temperatures warm into the mid-90s across much of the area as the more maritime air remains pinned closer to the coast. Heat indices in the relatively “drier” airmass only top out to around 100° or so, but once the seabreeze moves inland, somewhat more humid air behind it could allow heat indices to briefly spike up to around 105° or so, particularly in the Highway 17 corridor. A shower or thunderstorm in the afternoon and evening hours can’t be discounted, but don’t expect much relief.
We turn even warmer for Wednesday into Thursday. Highs top out around 97° on Wednesday and approach 98° on Thursday, with lows possibly not getting below 80° even inland of the coast Thursday morning. Showers and thunderstorms will be few and far between in the afternoons as northwest flow keeps drier air in place aloft and the seabreeze pinned closer to the coast. The elevated air temperatures, despite somewhat lower surface dewpoints especially inland, should still drive heat indices into the danger zone (105°+). In the immediate wake of the seabreeze, it wouldn’t be surprising to see some heat indices spike even higher, at least for a brief time.
Ridging begins to weaken somewhat as we get into Friday, and we’ll start to see a slight uptick in shower and thunderstorm chances in response. Friday will be another quite hot day with highs in the mid-to-upper 90s once more after starting out again near 80°. Troughing then gets re-established across the eastern US for the weekend, which will kick afternoon storm chances up a little higher while driving high temperatures down slightly (but not really enough to be perceptible this time of year!)
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