Today, we're getting a taste of what's to come starting in a month or so as summery heat and humidity surge into our state. Temperatures are heading for the lower 90s over most of the state this afternoon, with the heat index flirting with 100 in the hotter spots. We will remain rain-free across the state through this evening, but a cold front is on the way.
The cold front will move into the Upstate around daybreak Saturday and produce a shower or thunderstorm in some places. It's the least favorable time for thunderstorms because it arrives during the coolest part of the day. However, any thunderstorm that survives over the mountains can be locally severe with damaging wind and hail.
We will probably see spotty dying showers and storms cross the Upstate early Saturday. As the front moves into the rest of the state during the midday and afternoon, the chances of thunderstorms shift southeastward. The Storm Prediction Center puts most of the state in a level 1 of 5 risk area for severe storms due to the risk of locally damaging wind and hail. The risk is relatively low because the thunderstorms will remain spotty; we don't have a good setup for widespread storms due to weak upper-level support.
Drier and somewhat cooler air will push into the Upstate starting Saturday afternoon as the front shifts southward while the rest of the state remains sultry. Highs Saturday will range from the mid-80s in the Upstate to the lower 90s over the inland part of the Coastal Plain.
The front will become stationary over Georgia Saturday night into Sunday. Spotty thunderstorms with the front might sneak into areas south of I-20 and the Savannah River Basin Sunday afternoon, but other areas will enjoy a pleasantly warm spring day. It will remain warm, but not as hot as we're seeing today, and the humidity will drop to much more tolerable levels. Highs will range from the mid-80s in the Upstate to near 90 along the Coastal Plain away from the beaches. More of the state has a chance for a shower and thunderstorm Sunday night as the front begins a retreat northward.
Monday through Tuesday will be a tricky forecast period. The front will slowly slide northward, while the upper-level flow will be out of the west to northwest. Forecasting the timing of disturbances aloft that help trigger thunderstorms in that weather pattern is challenging. As a result, I have to allow for a shower or thunderstorm any time on those days. Should one of those disturbances pass through during the afternoon or evening when it's warmest, we'd have a risk for locally severe storms; some computer models show that.
What looks most likely to me is a round of locally gusty thunderstorms Monday afternoon and evening, then storms mostly pass by to our north on Tuesday afternoon and evening. I'm more confident that humidity will increase throughout the period, and it will remain warm with highs mostly 85-90, though a shower or thunderstorm early in the day where you live would keep it from getting as warm in your backyard.
Another cold front will move through on Wednesday, trailing a storm system passing by not too far to our north. Similar setups have brought us a notable outbreak of severe weather in the past. However, this time, the upper-level feature driving the cold front eastward looks disjointed on our computer models at the middle of next week, so we may not see a great setup for severe storms. There is also a question of timing: Will the front move in during the warmest part of the day, or wait until Wednesday night or early Thursday? We won't know the risk level or how widespread the storms will be until we get closer to the event, and a better agreement between computer models provides more clarity. It may be Monday or even Tuesday before we have good confidence, but it's something to watch.
Behind the front, cooler and drier air will move in for the end of next week. Perhaps there is a leftover shower or thunderstorm on Thursday (the best chance for that near the coast) before the front moves offshore, but right now, odds favor a spell of nice weather Friday through next weekend.
As expected, the drought situation has improved thanks to the widespread soaking rains we saw late last week, over the weekend, and earlier this week.
Unfortunately, our rain prospects for the next week are not great. Storms with the front coming through Saturday will be spotty, and any rain we see Sunday through Tuesday will also be spotty. Wednesday's cold front will be our only good chance for widespread rainfall over the next week. Also, long-range outlooks for the week after next favor near-average or slightly below-average precipitation. So, the drought will likely remain steady-state or backslide through the rest of the month.
