The Coldest Day of the Year

Did you know the coldest day of the year doesn’t arrive at the same time for everyone in the U.S.? While Groveland, California, is shivering through its chilliest day today, parts of the East Coast are still weeks away from their coldest temperatures. This is because the coldest day of the year, on average, occurs at least a month earlier on the western seaboard than on the eastern seaboard of the United States.

According to NOAA's Coldest Day of the Year interactive map, the farther west you are in the United States, the more likely it is that you have already experienced the coldest day of the year. The map is based on 30 years of temperature data and shows the average coldest day of the year at thousands of weather stations across the country. 

NOAA explains that in the eastern part of the United States, the "coldest day of the year is typically later ... thanks to cold air from snow-covered parts of Canada dipping down into the area."

Thanks, Canada!

If you want to know when the first snow of the year is most likely to fall, you can refer to NOAA's handy interactive First Snow Map. This map provides a nationwide guide to when you can expect the first snow of winter. It displays the date at your location when the chance of snow is at least 50%, based on historical weather records from 1981 to 2010.

Latitude and altitude play the biggest roles in determining when you are most likely to experience snow. On average, the farther north you are and the higher your altitude, the earlier you are likely to see snow.