A monthly electronic newsletter summarizing Minnesota climate conditions and the resulting impact on water resources.

Distributed on the Wednesday following the first Monday of each month.

State Climatology Office - DNR Waters

compiled 6/4/03

WHAT HAS HAPPENED

- precipitation totals in May 2003 were generally near normal across most of Minnesota. In portions of north central and northeastern Minnesota, May precipitation fell short of normal by one half inch to one inch. May precipitation topped the historical average by more than one inch in the Red River valley, in some southern counties, and in east central Minnesota. In the Twin Cities metropolitan area, May precipitation totals exceeded the norm by more than two inches.
(see: http://climate.umn.edu/cawap/monsum/monsum.asp, http://climate.umn.edu/img/journal/dry_winter_2002-2003/may2003dept.gif )
- May 2003 temperatures for Minnesota were near normal to somewhat cooler than normal. Temperature extremes ranged from 86 degrees at Morris on the 29th, to 11 degrees at Embarrass on the 2nd.
(see: http://climate.umn.edu/cawap/monsum/monsum.asp )


WHERE WE STAND NOW

- growing season precipitation totals to date (April 1 - June 2) are quite variable across Minnesota. Precipitation totals in portions of southwestern, northwestern, central, and east central Minnesota are above normal for the season, and rank above the 75th percentile for the period when compared with historical data. Growing season precipitation totals for some areas of north central and northeastern Minnesota are below normal, and in some cases rank below the 25th percentile.
(see: http://climate.umn.edu/doc/weekmap.asp )
- (repeated from last month) surface water levels in some northern Minnesota counties are well below historical averages. This can be attributed to precipitation deficits that have accrued over a 7-month period across much of Minnesota; and a 17-month dry spell affecting north central Minnesota, northeastern Minnesota, and scattered areas of southern Minnesota. The shorter of the dry spells commenced in mid-October 2002. The period from November 2002 through March 2003 was among the driest five-month periods in Minnesota's climate history. Five-month precipitation totals were less than two inches for large areas of Minnesota, and less than four inches for almost the entire state. April and May rains helped to ease moisture deficits across much of the southern two thirds of Minnesota. However, many areas in far northern Minnesota failed to receive substantial April and May rain. Longer-term precipitation deficits have impacted north central and northeastern Minnesota counties, as well as scattered areas of southern Minnesota, since early 2002. Precipitation shortfalls during this 17-month period are greater than six inches in some counties. 
(see: http://climate.umn.edu/doc/journal/dry_spells_2002-2003.htm )
- as of May 29, the National Drought Mitigation Center - U. S. Drought Monitor indicates that portions of north central and northeastern Minnesota are judged to be in the "D2 - Drought Severe" category. Most of the remainder of the northern one third of Minnesota is placed in the "D1 - Drought Moderate" or the "D0 - Abnormally Dry" classification. The NDMC index is a blend of science and subjectivity where intensity categories are based on six key indicators and numerous supplementary indicators.
(see: http://www.drought.unl.edu/dm/monitor.html )
- the Minnesota Agricultural Statistics Service reports on May 30 that the state's topsoil moisture was 8% surplus, 81% adequate, 10% short, and 1% very short.
(see: http://www.nass.usda.gov/mn/cwmn.htm , http://mrcc.sws.uiuc.edu/Watch/Drought/moisture.htm , http://swroc.coafes.umn.edu/Weather/Charts/Soil/2003/03_soil_water.htm , http://climate.umn.edu/img/soil_moisture/wassm12.gif )
- the U.S. Geological Survey indicates that stream discharge values for nearly three quarters of Minnesota's rivers rank between the 25th and 75th percentiles for the date. Low stream flows continue to be common in north central and northeastern portions of Minnesota. Stream discharge rates in some of these areas rank below the 10th percentile for the date.
(see: http://water.usgs.gov/cgi-bin/dailyMainW?state=mn&map_type=weekd , http://climate.umn.edu/dow/weekly_stream_flow/stream_flow_weekly.asp )
- water levels on many Minnesota lakes have dropped considerably from last summer's very high values. Water levels on lakes with significant connections to river systems are below average for the date. For many lakes located in land-locked basins, water levels are near average.
(see: http://www.dnr.state.mn.us/lakefind/index.html )
- the potential for wildfires is rated by DNR Forestry as high in portions of Lake county and all of Cook county. The fire danger is rated as moderate in the remaining areas of the northern one half of Minnesota. The fire danger is considered low in the southern one half of the state.
(see: http://www.dnr.state.mn.us/forestry/fire/ )


FUTURE PROSPECTS

- the June precipitation outlook from the Climate Prediction Center shows no significant tendencies away from climatological probabilities. June is historically the wettest month of the year with precipitation normals ranging from three and one half inches in western Minnesota, to over four inches and one half inches in many central and eastern Minnesota counties. The June temperature outlook also shows no significant tendencies away from climatological probabilities. Normal June high temperatures are in the low to mid 70's early in the month, rising to around 80 by month's end. Normal June low temperatures are in the low 50's to start the month, and rise to around 60 as the month ends.
(see: http://www.cpc.ncep.noaa.gov/products/predictions/30day , http://climate.umn.edu/img/normals/precip/precip_norm_06.htm , http://climate.umn.edu/img/normals/mean_temp_norm_adj/mean_temp_norm_adj_06.htm )
- the 90-day precipitation outlook for June through August shows no significant tendencies away from climatological probabilities. The June though August temperature outlook also indicates no significant tendencies away from climatological probabilities.
(see: http://www.cpc.ncep.noaa.gov/products/predictions/90day/lead01/index.html )
- the National Weather Service produces long-range probabilistic river stage and discharge outlooks for the Red River, Minnesota River, and Mississippi River basins. A hydrologic model is initialized using the current conditions of stream flow and soil moisture across a basin. The model is allowed to run into the future with multiple scenarios using more than 30 years of historical climatological data. The climatological data are weighted by 90-day climate outlooks for temperature and precipitation trends. Model output offers a complete range of probabilistic values of stream stage and discharge for numerous forecast points. The product provides a risk assessment tool which can be used in long-range planning decisions involving flooding or low flow concerns. These products are part of the National Weather Service's Advanced Hydrologic Prediction Service (AHPS) and are produced near the middle of each month. 
(see: http://www.crh.noaa.gov/ahps )


FROM THE AUTHOR

- none


NOTES FROM AROUND THE STATE

- none


UPCOMING DATES OF NOTE

- June 19, Climate Prediction Center releases 30/90 day temperature and precipitation outlooks


WEB SITES FEATURED IN THIS EDITION

http://climate.umn.edu - Minnesota Climatology Working Group
http://www.drought.unl.edu/ - National Drought Mitigation Center
http://www.nass.usda.gov/mn/cwmn.htm - Minnesota Agricultural Statistics Service
http://mrcc.sws.uiuc.edu/ - Midwestern Regional Climate Center
http://swroc.coafes.umn.edu/ - University of Minnesota Southwest Research and Outreach Center, Lamberton
http://water.usgs.gov/cgi-bin/dailyMainW?state=mn&map_type=weekd - U.S. Geological Survey, Minnesota
http://www.dnr.state.mn.us/waters/ - Minnesota DNR Division of Waters
http://www.dnr.state.mn.us/forestry/ - Minnesota DNR Division of Forestry
http://www.cpc.ncep.noaa.gov - Climate Prediction Center
http://www.crh.noaa.gov/ahps - National Weather Service, Central Region Headquarters


ACKNOWLEDGEMENTS

- Dr. Mark Seeley, University of Minnesota Extension Service

Contributions of information and suggestions are welcome!