HydroClim Minnesota for Early April 2015

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: April 2, 2015


What happened in March 2015:

  • March monthly precipitation totals were below historical averages across Minnesota. Monthly precipitation totals ranged from one-half inch to one and one-half inches below the long-term average.
  • An early spring snowstorm blanketed much of central and southeastern Minnesota with heavy, wet snow during the evening hours of March 22 and the morning of March 23. The heavy snow created travel hazards and led to school closures in some southeast Minnesota districts. The snow fell along a relatively narrow arc extending from northeast South Dakota to northeast Iowa. Snowfall totals in excess of eight inches were reported in McLeod, Sibley, Carver, Dakota, Scott, Rice, and Goodhue counties. Some daily snowfall total records were set. For most communities in the heavy snow band, it was the heaviest snow event of the 2014-2015 season.
  • Average monthly temperatures for March were two to four degrees above normal across much of the state. In far northeast and far southeast Minnesota, monthly mean temperatures were near normal. Extremes for March ranged from a high of 78 degrees F at Browns Valley (Traverse County) on the 15th, to a low of -40 degrees F at Cotton (St. Louis County) on the 5th. Numerous high temperature records were set around the state during the second week of March.

Where we stand now:

  • Minnesota's snow cover is gone in nearly all locales, except for northern St. Louis, northern Lake, and Cook counties were some snow remains in forested areas.
  • The U. S. Drought Monitor indicates that Moderate Drought conditions exist over 91% of Minnesota's landscape. The lack of snow during the 2014-2015 winter, combined with the dry early-spring weather, has led to precipitation deficits of three to five inches below average across the state since October 1st. The Drought Monitor index is a blend of science and subjectivity where drought categories (Moderate, Severe, etc.) are based on several indicators.
  • The U.S. Geological Survey reports that stream discharge values along many of Minnesota's major rivers are well below the historical median due to the lack of spring snowmelt runoff.
  • Water levels on many Minnesota ponds, wetlands, and lakes are lower than average due to the lack of spring recharge thus far this season.
  • 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. The first soil moisture status survey of the spring will be available April 6.
  • Frost is rapidly leaving the soil profile. During the early spring, frost leaves the soil from both above and below, leaving a layer of ice roughly two feet below the surface to thaw last.
  • Many lakes in the southern one-half of Minnesota are now free of ice. Lake ice-out dates for these lakes were one to two weeks earlier than the historical median.
  • The potential for wildfires is currently rated by DNR Forestry as Very High to Extreme across most of Minnesota. Historically, 80 percent of all wildfires in Minnesota occur during April and May.

Future prospects:

  • The April precipitation outlook offers equal chances of below-normal, near-normal, or above-normal conditions in most Minnesota counties. The April outlook leans towards below-normal precipitation in southwest Minnesota. April precipitation normals range from one and one-half inch in northwest Minnesota to around three inches in southeast counties. The historical probability of measurable precipitation for any given day in April ranges from 20 percent in the far northwest to 35 percent in the southeast.
  • The April temperature outlook indicates equal chances of below-normal, near-normal, or above-normal conditions across Minnesota. Normal April high temperatures are in the mid to upper 40s early in the month, rising to the low 60s by month's end. Early April normal low temperatures are near 20 in the north, near 30 in the south. By month's end, low temperatures average in the mid-30s in the north, near 40 in the south.
  • The 90-day precipitation outlook for April through June favors below-normal conditions across Minnesota. The April through June temperature projection indicates a tilt towards above-normal conditions for much of the state.]
  • 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. Spring flood risks remain well below historical probabilities.

 

Greg Spoden, DNR Climatologist