San Antonio is kicking off Saturday, June 20, with a 50% chance of showers and thunderstorms and a high near 91°F — check radar before you head out this morning and keep your day flexible.
Today’s Setup
The National Weather Service flagged a flash flood concern along and south of the I-10/US Highway 90 corridor overnight into this morning. A storm complex pushing up from the Rio Grande valley can produce rainfall rates of 2-3 inches per hour in heavy cells — if you’re near the River Walk, Mission Road, or the south side, watch water levels closely through mid-morning. The River Walk can turn dangerous fast when the drains are overwhelmed. Turn around, don’t drown.
The afternoon storm threat is lower but the heat is relentless. SE winds at 5-10 mph won’t cut the humidity, and the heat index could reach 101°F. Stay hydrated — an insulated tumbler 30oz keeps drinks cold far longer than any plastic bottle will in this air. talc free body powder is a Texas summer essential when it’s this sticky out.
Best Window To Be Outside
Before 10 AM CT is your best shot at a dry window, though some cells may already be active. Storm coverage should decrease through the afternoon, but a 30% chance lingers overnight into Sunday morning.
Rain & Heat Risk
The flash flood risk is real this morning south of I-10 — that includes areas near Lackland AFB and along US-90. The National Weather Service is watching this closely given the chaotic storm complexes in weak steering flow aloft. If the power flickers during overnight storms, a compact power station like the DARAN 288Wh Power Station — on sale for $90 for Prime members — keeps phones and fans running.
Tonight & This Weekend
Tonight’s low holds around 78°F with a lingering 30% storm chance — another muggy night. Sunday gets better: a 30% chance of morning showers before 10 AM CT clears to mostly sunny skies, but the heat index climbs as high as 105°F. South winds gust to 25 mph Sunday afternoon. A drier pattern settles in heading into next week.
Concerts This Weekend
Nate Bargatze: Big Dumb Eyes World Tour plays Moody Center ATX tonight — grab tickets on SeatGeek and pack a rain jacket for the drive. 5 Seconds of Summer: EVERYONE’S A STAR! World Tour hits Moody Center ATX Sunday, June 21 — evening conditions should be mostly clear. Later this week, Ariana Grande’s Eternal Sunshine Tour arrives at Moody Center ATX on June 24. Rep your fandom with an Ariana Grande t-shirt or Ariana Grande hat — and pick up tickets on SeatGeek.
Beat The Heat: Meals & Cool Gear
With 91°F and a heat index near 101°F, nobody should be standing over a stove. Cold Thai noodle salad or smoothie bowls are the move — a high-powered blender handles both in minutes. Set up an inflatable family pool in the backyard and arm the kids with water guns super soaker toys for an afternoon they’ll beg to repeat. Need ingredients? You can order groceries on Amazon and have everything for tonight’s dinner delivered to your door.
Next Few Days
Sunday: 93°F, mostly sunny after morning showers clear, heat index near 105°F with gusty south winds. Drier and hotter conditions hold through next week. Stay current with the San Antonio weather forecast and check outdoor gear deals to stay comfortable all summer long.
