October is here and with Fall officially underway the weather will be turning increasingly colder across the nation, leaving many wondering when we will experience our first snow. How early it snows obviously depends on your specific location and elevation as well as weather patterns from year-to-year. For some, the earliest snow could actually happen in September, while others do not see their first flakes until late-November or early-December. Below is a map that shows the earliest measurable snow recorded for select cities across the Lower 48. The National Weather Service considers measurable snow an accumulation of 0.1 inches or more. Many locations from the Rockies to the northern Plains, northern Great Lakes, and northern New England have received their earliest measurable snow in September. Below are a few of the cities and the specific date of their record earliest accumulating snow: (Source: TWC, NOAA)
Denver: Sept. 3, 1961
Billings, Montana: Sept. 7, 1962
Marquette, Michigan: Sept. 13, 1923
Salt Lake City: Sept. 17, 1965
Flagstaff, Arizona: Sept. 19, 1965
Minneapolis/St. Paul: Sept. 24, 1985
Fargo, North Dakota: Sept. 25, 1912
Omaha, Nebraska: Sept. 29, 1985
Burlington, Vermont: Sept. 30, 1992
A bunch of cities from the Midwest to the Great Lakes and Northeast have received their record first accumulating snow in October.
Boston: Oct. 10, 1979
Baltimore: Oct. 10, 1979
Washington: Oct. 10, 1979
Philadelphia: Oct. 10, 1979
Chicago: Oct. 12, 2006
Detroit: Oct. 12, 2006
Pittsburgh: Oct. 18, 1992
Indianapolis: Oct. 18, 1989
Cincinnati: Oct. 19, 1989
New York: Oct. 21, 1952
Seattle: Oct. 27, 1971
Portland, Oregon: Oct. 29, 1935
Ultimately, all of these dates mentioned are on the record-breaking early end of the spectrum. The average first accumulating snow typically arrives later in the season, as illustrated by the map below. Much of the Midwest and Northeast see their first measurable snow of the season in November or December. The South doesn’t see accumulating snow every year, but on average, January and February are the most favored months for at least a coating of snow. Since we are on the topic of snow, do you know just how much snow can fall in a 24-hour period in your part of the U.S.? Incredibly, almost every state in the U.S. has seen more than a foot of snow in 24-hours. Thundersnow can also sometimes occur, an indication of unstable air and strong upward motion in the atmosphere, resulting in heavy snow. Colorado leads the pack with the most extreme 24-hour snowfall record in the Lower 48 states. Below is a map showing your state record 24-hour snowfall.
