Missouri Winter 2010 Weather Summary

Pat Guinan
State Climatologist
Commercial Agriculture/University of Missouri Extension

Preliminary numbers are indicating the current winter in Missouri will rank as one of the coldest winters nearly 30 years. Since the winter of 1979-80, only three winters have had much below normal temperatures for the December through February period and this is the first time since the winter of 1981-82 that all three months reported below normal temperatures for the state.

An unusually persistent weather pattern contributed toward many below normal temperature days. One of the strongest cold snaps in more than a decade occurred during the first 10 days of January and the most recent current cold period had a grip on the Show Me state for much of February with temperatures averaging 5-7 degrees below normal.

As February came to an end, the preliminary average statewide temperature for winter in Missouri was 28.1 degrees F, which is similar to the cold winters of 1981-82 (27.6°F) and 2000-01 (28.3°F). This winter will rank as the 13th coldest winter for the state over the past 116 years.

Its not only been a cold winter, but a wet one as well. Winter precipitation was above normal across northern and central sections and has set the stage set for potential spring flooding. There has been little moisture loss since the cold and very wet October we witnessed last year. The state averaged nearly 10 inches of rain that month and it ranked as the second wettest October on record.

Evaporation rates were minimal with the unusually cold winter temperatures and soils remained frozen for extended periods of time, contributing to continued surplus soil moisture conditions statewide. River and streamflow levels are running higher than normal and lakes, livestock ponds and lagoons are at capacity. Below normal temperatures are expected to persist through March and will mitigate drying opportunities.

The St. Louis weather forecast office is forecasting a greater than 50% chance of significant flooding in their region over the next 90 days. Flood potential will be monitored closely over the next several weeks since snowpack over a large part of the upper Missouri and Mississippi River basins will likely translate to runoff as spring temperatures rise. Climatologically, spring is also Missouri’s wettest season.

Another aspect of this winter has been snowfall. The cold temperatures provided numerous opportunities for snowfall across the state with portions of far northwestern Missouri reporting nearly 50 inches of snow. Some communities in northwestern Missouri reported a continuous blanket of snow on the ground for three months! A weather observer located near Gallatin, MO, in Daviess county, reported 50.1 inches of snow so far this winter. Other reports from Nodaway county were approaching 50 inches. Generally, statewide snowfall totals ranged from 20-40 inches across the northwestern half of the state with 10-20 inches more common across the rest of Missouri.