April continues trend of warm and wet:
So far this month most Minnesota climate observers are reporting warmer and wetter than normal conditions. Temperatures are averaging 5 to 7 degrees F warmer than normal. Through April 19th eight daily record maximum temperatures have been tied or set within the climate observation networks, while thirty-nine daily record warm minimum temperature records have been tied or set.
Precipitation this month has been in surplus across much of central and southern Minnesota, but deficit in west-central and northwestern counties. Thunderstorms have brought new daily precipitation records to nine climate stations so far, including 2.45 inches to Winona Dam on April 19th. A number of areas have reported measurable precipitation on over half of the days of the month and a total of over 3 inches. Some other observers in southeastern Minnesota report over 5 inches for the month. The abundant precipitation this month has prohibited farm field work in many areas as soils are too wet for equipment.
Clearly this month is following a trend from the last two years (24 months) during which 22 months have been warmer than normal, and 16 months have been wetter than normal.
Look at early growing season:
One of the more recent forecast models deployed by NOAA is the North American Multi-Model Ensemble (NMME). This approach takes a composite from many different models to assess the probability of monthly and seasonal climate anomalies being above or below average values. For Minnesota, the recent NNME output favors warmer than normal conditions across the state for the May through July period, and less than normal precipitation. The precipitation outlook if it verifies would break the trend of wetter than normal which we have experienced over the past two years.
March for Science:
This year, Earth Day, April 22 (Sat), will also see widespread activity around the nation and state of Minnesota associated with the "March for Science." This is about demonstrating and speaking out for how important science is to understanding the world we live in, managing our natural resources, our societal infrastructure, and our care for each other. I will be part of the March for Science in St Paul at the State Capitol starting at 11am Saturday. Please join in if you care about science. There will be comments from many people advocating for science based knowledge to be used by our policy makers at all levels.
Larson-Allmaras Endowed Lecture:The Annual Larson-Allmaras Endowed Lecture will take place at 2pm in Rm 335 Borlaug Hall on the University of Minnesota St Paul Campus. This annual public lecture will focus on the Red River and Lake Winnipeg this year. Speakers include Dr. David Lobb and Dr. Donald Flaten from the University of Manitoba, and Aaron Buesing,from the District Office of the Army Corps of Engineers, and project engineer for the Fargo-Moorhead Diversion on the Red River.
Weekly Weather Potpourri:
There is an excellent article this month by NOAA's Caitlyn Kennedy about changing Plant Hardiness Zones and how those who garden should give this consideration when they decide about their spring planting. There is an interactive map to show how these zones have changed over time. For many parts of Minnesota Zone 4 and Zone 5a plants can now be planted in the landscape with minimal risk of winter injury. This NOAA analysis was done with the collaboration of the American Public Garden Association.
Romania, Hungary, Austria, and Ukraine reported winter-like conditions this week with cold temperatures, heavy snows, and strong winds. Travel and business were disrupted in those countries by a strong low pressure system that ushered in some Arctic air which dropped temperatures by 30 degrees or more.
A recent paper "Savor the Cryosphere" published by the Geological Society of America highlights the visible evidence of climate change through a temporal series of photographs of ice sheets and glaciers as they are retreated significantly over recent decades. This strong visual evidence dovetails nicely with the upward trend in temperature records at most of these places.
MPR listener question:Getting anxious about planting corn here in Blue Earth County. Any idea when we might see a few dry, sunny days to do so? In recent years we have been able to get some of our corn planting finished by late April.
Answer:If you have tile drainage, it will definitely be an asset this month in drying out wet soils. The next best opportunity appears to be Friday through early Wednesday, as we will see several sunny days with little chance of precipitation. Unfortunately from Wednesday (April 26) through the first few days of May looks to be a rainy period.
Twin Cities Almanac for April 21st:The average MSP high temperature for this date is 61 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 40 degrees F (plus or minus 7 degrees F standard deviation).
MSP Local Records for April 21st:
MSP records for this date include: highest daily maximum temperature of 95 degrees F in 1980; lowest daily maximum temperature of 34 degrees F in 1893; lowest daily minimum temperature of 22 degrees F in 1966; highest daily minimum temperature of 59 F in 1885 and 1926; record precipitation of 0.74 inches in 1912. Record snowfall on this date is 6.6 inches in 2002.
Average dew point for April 21st is 34°F; the maximum dew point on this date is 60°F in 1952; and the minimum dew point on this date is 11°F in 1984.
All-time state records for April 21st:The all-time state high temperature for today's date is 100 degrees F at Ada (Norman County), Montevideo, Georgetown, and Campbell in 1980; the all-time state low for today's date is -14 degrees F at Embarrass (St Louis County) in 2013. The all-time state record precipitation for this date is 2.49 inches at Warroad (Roseau County) in 1974. The all-time state record snowfall for this date is 15.0 inches at Lynd (Lyon County) in 1893.
Past Weather Features:
Perhaps the worst ever storm on this date (April 21) occurred in 1893. A large late season winter storm brought rain, sleet, ice, and snow to the state over three days from the 19th to the 21st. Snowfall totals ranged from 10 to over 30 inches for the 3-day storm, which shut down the railroad for a time. Blizzard conditions prevailed in parts of central Minnesota, where St Cloud reported an all-time record of 36 inches.
The hottest April 21st in state history occurred in 1980, a very dry, sunny month. At least 40 Minnesota climate stations reported a maximum temperature of 90°F that day, while Ada, Montevideo, Georgetown, and Campbell reached 100 degrees F, the earliest known date in Minnesota for such a reading. Even International Falls and surrounding areas reached 90 degrees F.
By far the coldest April 21st in state history was in 2013. Eight northern Minnesota communities reported subzero morning low temperatures, ranging from -1°F to -14°F. As far south as Worthington it was just 17 degrees F, while many daytime high temperatures only climbed up to the freezing mark.