San Antonio is heading into a warm, muggy Sunday with a high near 92°F under mostly cloudy skies — and a slim but real chance of isolated storms arriving late this afternoon or evening. If you’ve got outdoor plans at Brackenridge Park, the River Walk, or anywhere in the Hill Country, aim to wrap up before 4 PM CT.
Today’s Setup
South-southeast winds at 10 to 15 mph — with gusts up to 30 mph — are pumping Gulf moisture straight into the Alamo City. The National Weather Service says precipitable water values are running above normal at 1.6 to 1.8 inches, meaning any storm that fires could drop a quick quarter-inch to near an inch of rain in a short time. That’s textbook Flash Flood Alley behavior. NWS notes a moderate cap could suppress everything entirely and it could just turn out to be a warm, muggy day with no storms at all — but keep weather alerts on your phone if you plan to be near low-water crossings or the River Walk later in the day.
Best Window To Be Outside
Morning through early afternoon is your sweet spot. Golfers, tee times before noon are solid — overcast skies knock down direct glare and winds are still manageable. High humidity calls for a cooling neck towel and light clothes; it earns its keep when the heat index climbs. Anglers eyeing Medina Lake or Canyon Lake will find morning conditions favorable; cloud cover keeps surface temps comfortable and often triggers feeding. If spring pollen has been hammering you, an allergy relief nasal spray tucked in your bag is worth the pocket space on a breezy, muggy day like this.
Rain, Wind, and Heat Risk
The biggest hazards today are heat and humidity, not severe weather. Gusts up to 30 mph are possible, and that SSE wind feels thick. Monday turns up the heat further — a high near 93°F with a heat index as high as 101°F. Take that seriously if you’re working outdoors at Lackland, Fort Sam, or on a job site. Stay hydrated and limit midday exposure. For the rest of the week, the National Weather Service is flagging a wet, active pattern beginning early next week with heavy rain potential and localized flooding concerns — keep tabs on the San Antonio weather forecast as that timeline firms up.
Spurs Game 7 Tonight
If the Spurs need it, Game 7 of the Western Conference Semifinals against the Minnesota Timberwolves tips off tonight at Frost Bank Center. The game is indoors, so zero weather drama there. If you’re tailgating downtown beforehand, fire up a portable propane grill and get set up early — before any late-afternoon storm risk materializes. Show up dressed right with Official team gear on Fanatics, or Get tickets on SeatGeek if you’re still hunting for a seat in the building.
Also worth noting: Triumph brings their Rock & Roll Machine Reloaded Tour to Frost Bank Center on Thursday, May 21 — check back on the forecast before that one.
Dinner Tonight
Perfect grilling weather — fire up the grill for burgers, steaks, or grilled chicken with corn on the cob before the storms have any chance to show up. An instant-read meat thermometer takes all the guesswork out of doneness, and a grill brush and scraper set keeps your grates ready for the whole summer ahead. Need ingredients? You can order groceries on Amazon and have everything for tonight’s dinner delivered to your door.
Next Few Days
Monday: near 93°F, heat index up to 101°F — stay cool. Early-to-mid next week, NWS Austin/San Antonio expects a significant shift to a wetter, more active pattern with heavy rain and potential localized flooding. If you’ve got outdoor plans along the Riverwalk or Hill Country, keep a close eye on updates. Check outdoor gear deals to gear up for whatever the week throws at you.
