San Antonio woke to partly cloudy, muggy skies Wednesday morning, with temperatures in the low 70s and a high near 85°F expected today. A few sprinkles or an isolated shower are possible this morning, but most of the afternoon should stay partly sunny and breezy with east winds of 10 to 15 mph. The real story arrives late Wednesday into the overnight hours, when renewed thunderstorm activity could drop heavy rain in spots.
Tonight's Storms Could Be Heavy
Late Wednesday evening (May 20) there is a 70% chance of showers and thunderstorms, with new rainfall amounts of a half to three quarters of an inch possible overnight. The National Weather Service Austin/San Antonio warns that storms may produce brief heavy downpours that lead to localized flooding, and that isolated severe storms with damaging wind gusts and hail are possible. Forecasters expect the heaviest activity between about 7 p.m. and 1 a.m., with east-southeast winds easing to 5 to 10 mph overnight.
Weekend Outlook And Memorial Day
The active, unsettled pattern looks likely to hang around through the Memorial Day holiday weekend, with additional rounds of storms possible Friday into Monday and the highest rain chances on Saturday. Our earlier storm outlook flagged this trend, and city officials are already urging residents to be aware of water-over-road closures. For local guidance on flood safety and reporting street closures, consult the City of San Antonio flood resources.
How To Prepare
Plan for slower evening commutes and pockets of standing water on low-lying streets. If you encounter a flooded road, turn around and do not drive through it. Keep phones charged, bring rain gear, and secure loose patio furniture, and have multiple ways to receive warnings in case flash flooding develops. If you have outdoor plans for the holiday weekend, consider moving them earlier in the day or lining up an indoor backup plan so the storms do not wash out your fun.
