A monthly electronic newsletter summarizing Minnesota's climate conditions and the resulting impact on water resources. Distributed on the first Thursday of the month.
State Climatology Office - DNR Division of Ecological and Water Resources, St. Paul
distributed: March 5, 2015
What happened in February 2015:
- February monthly precipitation totals were below historical averages in nearly every Minnesota community. In many locales, monthly precipitation totals were roughly one-half of the long-term average. February is Minnesota's driest month. For that reason, below-average monthly precipitation totals in February have relatively little impact on the state's hydrologic landscape.
[see: February 2015 Precipitation Map | February 2015 Precipitation Departure Map | February 2015 Climate Summary Table]
- There were no major winter storms in Minnesota during the month of February. However, three moderate snow events occurred during the month: February 3-4, February 10, and February 25.
[see: February 3-4 Snowstorm | February 10 Snowfall Totals | February 25 Snow Event]
- Average monthly temperatures for February in Minnesota were well below historical averages, ranging from 8 to 13 degrees below normal. Extremes for February ranged from a high of 49 degrees F at Pipestone (Pipestone County) on the 7th, to a low of -43 degrees F at Cotton (St. Louis County) on the 20th. A number of minimum temperature records were set at various Minnesota locales during the final two weeks of the month.
[see: February 2015 Climate Summary Table]
Where we stand now:
- Snow depths are highly variable across Minnesota. Many northwest, southwest, and south central communities have little or no snow on the ground. Whereas, portions of southeast Minnesota report six inches of snow depth and much of northeastern Minnesota, inland from Lake Superior, has 16 inches or more of snow cover. Snow depths are below median for this time of the year in many Minnesota communities.
[see: NWS Snow Depth Estimation Map | Weekly Snow Depth Maps]
- The U. S. Drought Monitor, released on March 5, indicated that Abnormally Dry conditions exist over nearly all of Minnesota, the result of a dry late summer and autumn, and a snow-sparse winter. Two small areas of west central and north central Minnesota are placed in the Moderate Drought category. The Drought Monitor index is a blend of science and subjectivity where drought categories (Moderate, Severe, etc.) are based on several indicators.
[see: U.S. Drought Monitor]
- In their final report of the season (November 24), the Minnesota Agricultural Statistics Service reported that topsoil moisture across 20 percent of Minnesota's landscape was described as Short or Very Short. Topsoils across Minnesota are solidly and deeply frozen. Therefore, very little overwinter precipitation will enter the soil profile.
[see: Agricultural Statistics Service Crop Progress and Condition]
- Cold temperatures and relatively little snow insulation have driven soil frost depths down to two to three feet (under sod) at many Minnesota observing locations. Soil frost depths under surfaces kept free of snow, such as streets and roads, have advanced to four to six feet at some locations. Historically, frost reaches its maximum depth in late February and early March.
[see: Corps of Engineers Snow, Ice, Frost Data | National Weather Service Frost Depth Data | MnDOT Road Frost Depths | University of Minnesota - St. Paul Campus Soil Temperatures Under Sod]
- Minnesota lakes and rivers are nearly completely ice covered. Lake Superior is 91% ice-covered. Lake and river ice is never completely safe. Caution is always advised when venturing onto the ice.
[see: DNR Conservation Officer Reports | Great Lakes Ice Concentration]
- The March precipitation outlook offers equal chances of below-normal, near-normal, or above-normal conditions in all Minnesota counties. Historically, average March precipitation totals range from near three-quarters of an inch in northwestern Minnesota to around two inches in southern sections of the state. March is a transition month when cold, dry continental air masses are gradually replaced by warmer, moister air on a more frequent basis. This is demonstrated by the fact that March's normal precipitation is 50 percent higher than February's normal precipitation, the greatest percentage increase between any two successive months.
[see: Climate Prediction Center 30-day Outlook | March Precipitation Normal Map]
- The March temperature outlook tilts towards below-normal conditions across Minnesota. Normal March high temperatures climb from near 30 degrees early in the month to the low to mid-40s by month's end. Normal March lows begin the month in the single digits above zero in the far north and mid-teens in the south. By late March, normal lows are in the low 20s in the north, near 30 in the south.
[see: Climate Prediction Center 30-day Outlook | March Temperature Normal Map]
- The 90-day precipitation outlook for March through May offers equal chances of below-normal, near-normal, or above-normal conditions across Minnesota. The March through May temperature projection also indicates equal chances of below-normal, near-normal, or above-normal conditions.
[see: Climate Prediction Center 90-day Outlook]
- The National Weather Service produces long-range probabilistic river stage and discharge outlooks for the Red River, Minnesota River, and Mississippi River basins. These products address both high flow and low flow probabilities. At this time, spring flood risks remain well below historical probabilities.
[see: National Weather Service - North Central River Forecast Center]
From the author:
Upcoming dates of note:
- March 19: National Weather Service releases 30/90 day temperature and precipitation outlooks
Greg Spoden, DNR Climatologist