|HydroClim Minnesota - November, 2000
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
WHAT HAS HAPPENED
- October precipitation was below normal across most of Minnesota. With the exception of some northern counties, precipitation across the state was very light until the final days of the month. October precipitation totals ranged from one half inch to one and one half inches below average in most communities. Precipitation totals in some northwestern and north central Minnesota locations exceeded the norm by more than an inch.
- early November precipitation was extraordinarily heavy. As of the morning of November 7th, all of Minnesota had received more than one inch of rain for the month; most of the northern two thirds of Minnesota had received more than two inches; and November precipitation totals in many areas topped three inches.
- October temperatures were two to five degrees above the historical average across Minnesota. A record-breaking cold snap on October 8th and 9th was more than counterbalanced by mild mid-October weather including record-breaking warmth on the 19th.
WHERE WE STAND NOW
- the heavy early November rainfall brought relief to parched water resources affected by the significant precipitation deficits found in southwestern, central, east central, and far northeastern Minnesota over the last 14 months. Falling before soil freeze-up, the rains helped to replenish dehydrated topsoil in these areas. Additionally, surface hydrology levels have climbed in response to the heavy precipitation. Nonetheless, the accumulated long-term precipitation shortfalls were significant in these areas, and precipitation remains four to seven inches below normal for the year. Unfortunately, the torrential early November precipitation also fell upon northwestern Minnesota, a region already wet from heavy late summer and autumn rains. In many northwestern Minnesota counties, annual precipitation is far above average and streams in the area are at or above bank full.
- as of their November 2 release, the National Drought Mitigation Center - "U.S. Drought Monitor" shows much of southwestern and central Minnesota in their "D1" category ("Drought - First Stage"). The remainder of the southern two thirds of Minnesota falls in the "D0" grouping ("Abnormally Dry). The November 9 release will reflect the heavy early November precipitation and the depiction is sure to change. The NDMC index is a blend of science and subjectivity where intensity categories are based on six key indicators and numerous supplementary indicators.
- the November 4th Palmer Drought Severity Index (PDSI) depicts most of Minnesota in the "Near Normal" category. Counties in north central Minnesota are categorized as experiencing an "Unusual Moist Spell". The Palmer Drought Severity Index is used for assessing long-term meteorological conditions.
- the Minnesota Agricultural Statistics Service reports that topsoil moisture conditions across the state were rated 5% very short, 22% short, 60% adequate, and 13% surplus as of Friday, November 3. This is a large decrease from last month in the amount of acreage categorized as short or very short. Due to excessive soil moisture, farmers in the northern third of the state will need to wait for the ground to freeze in order to complete harvest.
- discharge values for central and east central Minnesota streams have rebounded significantly over the last seven days. According to the U.S. Geological Survey, most streamflows in these regions now fall between the 25th and 75th percentile when compared to historical values for the date. A significant number of streams in the northern one half of Minnesota are above the 75th percentile. Stream discharge ranks in the "high flow" to "record flow" categories along the Red River and its tributaries.
- the wildfire danger potential, determined by DNR Forestry, changed dramatically over the last two weeks. The fire danger is now considered "low" for all Minnesota counties.
- the 90-day outlook for November through January indicates near normal precipitation statewide. The November through January temperature outlook also calls for near normal conditions throughout Minnesota.
FROM THE AUTHOR
Conversely, soil moisture and surface water systems are at unusually high levels in northwestern Minnesota, and above average spring snow-melt runoff or above average early spring rains would pose problems in the spring of 2001.
(excerpted from "St. Cloud October, 2000 Weather Summary)
We got more rain during October 2000 in Saint Cloud than we did in September. However, the October rainfall of 1.61 inches was still more than half an inch below normal. The total growing season (1 April through October 31) rainfall at Saint Cloud Municipal Airport now totals only 14.06 inches, more than eight and a half inches below normal. This is the fifth lowest growing season rainfall among the 108 years on record.
Ironically, 3 minutes after the October statistics became final, a line of thunderstorms began producing rain in St. Cloud at 1203 AM on November 1. By late morning, 0.88 inches had been recorded at the Saint Cloud Airport (1.14 inches at Saint Cloud State University), breaking a record for daily rainfall on November first (old record of .86 inch on 1 November 1974). The heavy rain also provided nearly three-quarters of the normal rainfall for the entire month of November. Still, the dry conditions combined with downed foliage, high winds, and warm temperatures frequently during October to produce local grass and prairie fires throughout central Minnesota. However, none of these fires reached the size of the fire in northern Anoka County which burned more than 1000 acres.
- from Bob Merritt, DNR Waters Area Hydrologist - Detroit Lakes
Field moisture conditions in Eastern Polk county are wet. Definitely don't want to drive on black dirt and fields have standing water in swales and tractor tire ruts. Soil moisture is up in the whole area.
- November 16, Climate Prediction Center releases 30/90 day outlooks
http://climate.umn.edu - Minnesota
Climatology Working Group
Bob Weisman, Meteorology Professor, Earth Sciences Department - St.
Cloud State University
Contributions of information and suggestions are welcome!