Cold Snap Forecast: When Is the Next Cold Front Near You?

Enter your ZIP code above. The tool plots the next 7 nights from the National Weather Service forecast against the normal low for each date at your nearest reference station, names the coldest night ahead and how far below normal it runs, and adds the Climate Prediction Center outlook for the two weeks after.

Each night's forecast low is compared with the NOAA normal low for that date at the nearest reference station. A night 20 or more degrees below normal is an arctic blast, and so is a night below zero where the normal low is 10°F or warmer. A night 10 to 19 below is a cold snap. A night 5 or more below, or a week that runs 3 or more below on average, is colder than normal, and a week 5 or more above is mild. Measuring against the local normal is what makes a 25°F night a cold snap in Atlanta, where the coldest week has a normal low of 35°F, and a mild one in Minneapolis, where it is 8°F.

For the biggest city in 38 of the 49 states, the coldest week of the 1991 to 2020 normals starts in January, for example Portland (Jan 23 to 29), Manchester (Jan 21 to 27) and Burlington (Jan 24 to 30). In the other 11 it starts in December, including Billings (Dec 29 to Jan 4), Cheyenne (Dec 17 to 23) and Denver (Dec 17 to 23). The ranking below lists every state.

No. NOAA's climate.gov describes the polar vortex as a band of strong westerly winds in the stratosphere, 10 to 30 miles above the North Pole, and says: “It’s the polar jet stream that plays such a big role in our day-to-day winter weather in the mid-latitudes, not the polar vortex.” Disruptions of the vortex often lead to cold air outbreaks, it adds, but NOAA's Amy Butler notes that plenty of them happen in a winter without any help from the vortex.

About a week in detail. The National Weather Service forecast gives a low for each of the next 7 nights. Past that, NOAA's Climate Prediction Center issues 6 to 10 day and 8 to 14 day outlooks, which give the odds that the stretch runs colder or warmer than normal rather than a temperature. Each of the three outcomes happens one time in three over 1991 to 2020, so the outlook only leans a way when the odds beat one in three.

It is the National Weather Service's warning for dangerous cold. On Oct 1, 2024 the Wind Chill Warning became the Extreme Cold Warning, the Wind Chill Watch became the Extreme Cold Watch and the Wind Chill Advisory became the Cold Weather Advisory. In the Weather Service's words: “These changes seek to clarify that cold can be dangerous with or without wind, addressing a common misconception that extreme cold is only tied to colder temperatures when there is wind.”

The first night of 50°F or colder is a fair marker. In the median of the last 10 falls it came around Oct 23 in Jacksonville, around Oct 10 in Birmingham, around Oct 12 in Jackson, around Nov 2 in New Orleans, around Oct 20 in Houston and around Nov 15 in Phoenix. Each Gulf and desert state page has the first freeze too.

Honolulu's coldest week is usually Jan 15 to 21, with a normal low of 67°F. The coldest night of the last 10 winters at the airport was 56°F on Dec 4, 2021, and the record is 52°F on Jan 20, 1969. A Hawaii ZIP in the tool compares against Honolulu, and the Hawaii winter forecast covers the season.