Honestly, if you've been glancing at the forecast for Sunday, January 18, 2026, you've probably noticed something a bit jarring. We aren't just looking at a standard January chill. Across a massive chunk of the United States, Sunday is shaping up to be a legitimate weather event that’s going to catch a lot of people off guard—especially down South.
The big headline for Sunday is the high temperature of 31°F and a bone-chilling low of 7°F for the broader United States forecast area. When the mercury hits 31 degrees as a high, you know the arctic gates have swung wide open. We're talking about a day where the sun might be out, but the air has a bite that doesn't care about the sunshine.
What’s Actually Happening With the Sunday Temperature?
It’s easy to say "it's winter, it's supposed to be cold," but the mechanics behind this Sunday’s freeze are pretty specific. We’ve got a massive, highly amplified trough of low pressure digging deep into the central and eastern U.S. Basically, a cold front is sweeping down from the Plains and the Midwest, and it's bringing some serious baggage with it.
In places like San Antonio, they are bracing for their very first hard freeze of the season. We’re talking about a drop where the National Weather Service has already flagged temperatures between 26 and 32 degrees for Sunday morning. If you’re in Bexar County, you’re looking at about six to eight hours of sub-freezing air. That’s enough to kill off those sensitive plants you forgot to bring in and potentially wreak havoc on exposed pipes.
Further north in Chicago, Sunday is a different beast entirely. It’s not just "cold"—it’s dangerous. The high is hovering around 18°F, but with wind gusts hitting 30 mph, the "feels-like" temperatures are diving into the single digits or even below zero. If you're heading to the Rams vs. Bears game at Soldier Field, you're looking at a 60% chance of snow and winds that will make a 20-yard pass feel like a miracle.
Regional Breakdown: From Sunshine to Snow Squalls
Weather in the U.S. is never uniform, and Sunday is a perfect example of that. While the national average high is that 31°F mark, the experience on the ground varies wildly depending on your zip code.
- The Southeast: This is where the surprise is. Places like Atlanta and Macon, Georgia, are opening warming centers. There's a legit possibility of snow in central Georgia, with totals ranging from a dusting to maybe an inch. It's not much, but in Georgia, an inch of snow on a Sunday morning is a city-stopper.
- New England: They’re tracking a coastal low moving up from the Carolinas. For Boston and Foxborough, the Sunday afternoon forecast is messy. Light snow could start during the Patriots game, intensifying as the evening goes on. Southeastern Massachusetts could see 3 to 5 inches by the time everyone’s tucked in Sunday night.
- The West Coast: It’s a totally different world. In places like Santa Clara and Richmond, California, temperatures are staying much more civilized, with highs in the 60s (around 62°F to 66°F). There's some patchy fog to deal with, but no one's shoveling snow out there.
Why the UV Index and Humidity Matter on a Day Like This
It sounds weird to talk about the UV index when it's 31 degrees out, but the forecast is calling for a UV index of 2 on Sunday. It’s low, sure, but with the "sunny" conditions expected for much of the country, that sun-on-snow glare is real.
The humidity is sitting at 50%, which is actually quite dry for a winter day. Dry air feels colder because it zaps moisture off your skin faster. Combine that with a steady 12 mph west wind, and you’ve got a recipe for chapped lips and "ice cream headaches" just by walking to your car.
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Making Sunday Manageable: Real-World Steps
Since we know the temperature is going to bottom out at 7°F overnight into Monday, Sunday is your window to get ready.
First, if you're in the South or the Plains, check your "P's": People, Pets, Pipes, and Plants. It’s a cliché because it works. For those in the Northeast, the Sunday afternoon snow is the "travel" window closer. If you have errands, get them done before 2:00 PM when the coastal low starts to really crank up.
For the football fans and outdoor workers: layers aren't just a suggestion. Wicking base layers are a must because if you sweat while shoveling or walking to the stadium, that moisture will turn into an ice block against your skin once you stop moving.
Sunday is going to be a sharp reminder that winter has finally found its teeth. Stay warm, keep an eye on the local radar if you're in the path of that coastal low, and maybe just keep the kettle on.
Actionable Next Steps:
- Check your exterior faucets: Disconnect hoses and wrap any exposed pipes tonight, especially if you're in the Texas or Georgia freeze zones.
- Plan your travel for Sunday morning: If you're in New England or the Midwest, the heaviest snow and wind gusts are timed for the late afternoon and evening.
- Bring in sensitive greenery: Any potted plants left outside in the South will likely not survive the 26-degree dip expected Sunday morning.