Prepping in San Antonio
San Antonio sits in Flash Flood Alley. In June 2025, a pre-dawn flash flood killed 13 people in the city. Alerts that wake you up matter here more than anywhere.
- Flash floods
- Extreme heat
- Freezes and outages
Sign up today
The official San Antonio alert and lookup tools. Each takes a few minutes and works even if you do nothing else on this page.
- Bexar County REAN alertsSign up for REAN alerts
The Regional Emergency Alert Network sends free calls, texts and emails for emergencies in Bexar County. Register your cell phone and home address; landlines are already included.
- TexasReadyGo to TexasReady
The City of San Antonio points residents to TexasReady to sign up for emergency alerts and learn how to prepare.
- STEAR registryRegister with STEAR
If someone in your home would need help evacuating, register with the State of Texas Emergency Assistance Registry online or by calling 2-1-1.
Links checked October 2026. Wireless Emergency Alerts reach most phones automatically; these add local detail.
What can go wrong in San Antonio
- Flash flooding
- Heavy rain turns creeks and low-water crossings deadly within minutes. Most flood deaths happen in cars or near swollen creeks, often at night.
- Extreme heat
- Long stretches near or above 100°F, with warm nights, make outages dangerous for older adults and anyone without AC.
- Winter freezes
- February 2021's winter storm knocked out power and water across the city for days and left burst pipes behind.
- Hail and severe storms
- Spring storms bring large hail and damaging wind that break windows and roofs.
- Tropical rain
- Storms moving inland from the Gulf can drop days of heavy rain on the region.
What that means for your plan
Never drive or walk into flooded roads. Turn around; it takes very little moving water to carry off a car. Learn the low-water crossings on your routes.
Have alerts that wake you at night. A NOAA weather radio with a battery backup and phone alerts turned on cover the flash floods that come before dawn.
Plan for heat and cold without power: a way to cool one room, warm sleeping bags for freezes, and two weeks of water for boil notices.
Do these first, in this order
- Alerts that wake you
A NOAA weather radio plus REAN, for night flash floods.
Radios and communication guide - Two weeks of water
Freezes and floods both bring boil-water notices.
Water storage and filters guide - Power station
Fans, phones and medical devices through outages.
Power stations and generators guide - Warmth without power
The lesson of February 2021.
Lighting and staying warm guide - Battery CO alarm
For anyone using a generator or gas heat in an outage.
Power stations and generators guide - First-aid kit
Storm cleanup brings cuts and injuries.
First aid and medical guide
Questions
Why is San Antonio so prone to flash floods?
It sits in Central Texas's Flash Flood Alley, where thin soil and steep terrain send heavy rain into creeks fast. Low-water crossings flood within minutes.
How do I get emergency alerts in San Antonio?
Register for Bexar County's REAN alerts, sign up through TexasReady as the city recommends, and keep Wireless Emergency Alerts turned on in your phone settings.
How ready is your San Antonio home?
The quiz weights every item for suburbs risks and shows your top gaps. About 3 minutes, no sign-up.