North Dakota is widely known for its intense cold and significant snowfall, characteristics that define its winter season. Understanding typical patterns and influencing factors helps to anticipate when the first flakes might appear and accumulate each year.
Average First Snowfall Dates
Across North Dakota, the first measurable snowfall generally occurs between late October and mid-November. This timeframe marks the transition from autumn to colder winter months. It is important to distinguish between scattered flurries and measurable snowfall that accumulates on the ground.
Fargo typically sees its first accumulating snow around November 2. In Bismarck, the average first measurable snowfall ranges from late October to early November, with averages recorded as October 26 and November 8. Minot’s snowy period often begins around October 16, while Grand Forks typically experiences consistent snow cover starting in mid-November.
Factors Influencing Early Snow
The timing of North Dakota’s first snowfall depends on specific meteorological conditions. For snow to form and fall, air temperature from the clouds to the ground needs to be at or below 32°F (0°C). Heaviest snowfalls often occur when air temperatures are slightly above freezing, between 32°F (0°C) and 35.6°F (2°C), as this allows snowflakes to stick together, creating larger flakes. Adequate moisture is also necessary, as very cold and dry air can limit significant snowfall.
Cold air masses, particularly those originating from the Arctic, play a significant role in bringing temperatures down. Specific weather patterns, such as “Colorado Lows,” are crucial for substantial early-season snow events. These systems draw considerable moisture northward from the Gulf of Mexico, leading to heavy snowfall as they move across the Central Plains. In contrast, faster-moving systems like “Alberta Clippers” typically bring less moisture, resulting in lighter snow accumulations.
Regional Variations Across North Dakota
The timing of the first snowfall can exhibit subtle differences across North Dakota due to geographical nuances. Western parts of the state, including cities like Williston and Dickinson, often experience colder temperatures slightly earlier. Williston has recorded its earliest snowfall as September 12. Dickinson’s average October snowfall is around 3.7 inches.
Central North Dakota, represented by cities like Bismarck, typically sees an average of 2.5 inches of snow in October. In eastern North Dakota, including Fargo and Grand Forks, the first measurable snowfall tends to occur slightly later than in the western regions. Fargo’s average October snowfall is 1.2 inches, while Grand Forks averages 1.5 inches for the same month. These regional distinctions highlight that the precise kickoff of the snowy season can vary by a few weeks.
Historical Earliest and Latest Occurrences
North Dakota’s recorded weather history shows considerable variability in first snowfall dates, illustrating the unpredictable nature of the climate. The earliest recorded snowfall in Bismarck occurred on September 16, 1965. Fargo’s earliest recorded snow event was on September 25, a date that has occurred twice, most recently in 1942. Grand Forks experienced its earliest snow on September 24, 1912. In western North Dakota, Williston holds the record for the earliest snowfall, which was September 12, 1903.
Conversely, the latest first snowfalls on record extend well into the spring. Bismarck’s latest recorded snowfall occurred on May 26, a date seen twice, most recently in 1965. Fargo’s latest first snowfall was on May 21, 1963. Grand Forks recorded its latest first snow on May 27, 1947. Williston also saw a late first snowfall on May 26, 1965. These historical extremes underscore that while averages provide a guide, the actual timing can fluctuate significantly from year to year.