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Earliest snow on record in 10 major U.S. cities, from Denver to Charleston

Earliest snow dates on record for 10 U.S. cities, from Denver in early September to Charleston in December, show when winter weather has first arrived

The earliest snow on record in Denver fell on September 3, 1961. In Charleston, South Carolina, the record-early snow did not come until December 11, 1958. Those two dates mark the calendar edges of the 10 cities profiled here. The cities in between differ in latitude, elevation and distance from large bodies of water.

The city dates come from an AccuWeather list of the earliest snow dates in U.S. cities, which covers 33 cities in all. This article looks at 10 of them, chosen to span the country from the Rocky Mountains and the northern Plains to the Great Lakes and New England. The selection also includes the Pacific Northwest, North Texas and the Southeast coast. Each date is a historical record, not a forecast.

A record-early date is also different from a typical first snow. It marks the single earliest snowfall in a city's history of observations. In other years, the first flakes in each of these cities arrived later. Readers looking for when to expect a first snowfall should treat these dates as the outer limit of what has already happened. They are not a guide to an ordinary season.

The Weather Channel compiled a parallel set of records by state, counting measurable snowfall as at least one-tenth of an inch. In its tally, 19 states have an earliest-on-record snowfall in September. That group includes Colorado, North Dakota, Utah, Vermont, Washington state and Texas. Another 20 states, among them New York, Massachusetts and Illinois, have records set in October. Eight states, including South Carolina, have November records. Florida, Hawaii and Louisiana showed no data in the report.

State records and city records measure different places, so they do not always match. Washington state's earliest snow on record falls in September, for example. Seattle's own record-early snow came on October 27, 1971.

Early-season snow brings its own hazards. The National Weather Service has warned that snow landing on ground that is still warm makes for slushy, slippery surfaces. The agency also said trees still holding their leaves can bend under the extra weight. That can break branches and may cause power outages, according to the agency. Its advice is to check the local forecast and leave extra time for travel.

Denver's earliest snow on record fell September 3, 1961

Denver's earliest recorded snow fell on September 3, 1961, according to an AccuWeather list of 33 U.S. cities.

That date came before fall officially began. The autumnal equinox, which marks the astronomical start of the season, comes later in September. By that measure, the city's record snow arrived during astronomical summer.

September 3, 1961, was a Sunday. Labor Day fell the next day. Many Americans treat that holiday weekend as the unofficial end of summer. In 1961, it brought Denver its earliest snow on record.

Denver is the capital and most populous city of Colorado. Its nickname, the Mile High City, refers to an elevation of about one mile above sea level. A marker on a step at the west entrance of the Colorado State Capitol shows that height. Air temperature generally drops with height in the lower atmosphere. That altitude is one reason snow can reach Denver so early in the season.

The city sits on the western edge of the Great Plains, along the South Platte River. West of downtown, the land rises into the Front Range of the Rocky Mountains. That position leaves Denver open to cold air masses moving south across the Plains from Canada. It also puts the city in the path of weather systems crossing the mountains.

The terrain also shapes how snow forms there. When winds blow from the east, they push moist air west toward the Front Range. As that air rises along the higher ground, it cools and can release snow over Denver and nearby cities. Meteorologists call this pattern upslope snow.

The mountains can work the other way, too. Chinook winds descending the eastern slopes of the Rockies warm and dry the air as they sink. Those winds can melt snow in the city quickly. As a result, snow on the ground in Denver can vanish soon after a storm ends.

Bismarck, North Dakota, earliest snowfall date: September 16, 1965

Bismarck's earliest snow on record fell on September 16, 1965, according to AccuWeather's list of first-snow dates for U.S. cities. Among the 10 cities in this selection, only Denver has an earlier record date.

That mid-September snow arrived before the autumnal equinox, while the calendar still showed summer.

Bismarck is the capital of North Dakota. It sits on the east bank of the Missouri River in the south-central part of the state. The city of Mandan lies across the river.

The city is on the northern Great Plains, far from any ocean. That distance gives Bismarck a continental climate. Summers are hot, winters are cold and temperatures swing widely between seasons.

Large bodies of water store heat and release it slowly. In coastal places, that stored warmth eases the shift into autumn. Bismarck has no such buffer.

Latitude adds to the picture. Of the 10 cities profiled here, only Seattle lies farther north than Bismarck. Seattle's record-early snow nonetheless came in late October.........

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