April high winds continue, but with huge temperature contrast:
April winds continue to howl in most places. Many climate stations report a high frequency of wind gusts over 30 mph (10 or more days). MSP reports wind gusts greater than 30 mph on 11 of the first 14 days, while Rochester reports 10 such days and 6 days with wind gusts over 40 mph.
While high winds are the constant climate element this month, temperatures are by far the most variable. During the first week of the month (April 1-7) temperatures around the state averaged 7°F to 9°F cooler than normal, with even some record-setting cold readings like:
-a maximum temperature of only 24°F at Park Rapids (Hubbard County) on April 5
-a maximum temperature of only 25°F at Pipestone on April 6th
-a minimum temperature of -5°F at Brimson (St Louis County) on April 7th
-a minimum temperature of -2°F at Hibbing on April 7th
Then starting on April 8th, the strong winds turned more southerly and ushered in very warm air temperatures indeed. Temperatures for the second week of April (April 8-14) averaged 18-22 degrees F above normal. Many climate stations including MSP reported their first 60°F reading on April 8th, their first 70°F reading on April 10th, and their first 80°F reading on April 11th.
Many daily warm maximum and minimum temperature records within the state climate network were shattered by the influx of very hot and dry winds from the south starting on April 11th. At least 15 long term climate stations reported new record high temperatures on April 12th, including:
71°F at International Falls
87°F at Rochester
88°F at MSP
New Ulm, Red Wing, Owatonna, and Winona all reported 90°F readings that day (April 12) which tied the state record high temperature at Beardsley (Big Stone County) set in 1931. In addition, MSP reported a record warm overnight low temperature of 63°F on April 12th and Rochester a record warm low of 57°F.
The warm weather pattern continued on April 13 with many climate stations reporting record high temperatures in the mid to upper 80s F. Some new record highs from long-term climate stations included:
90°F at Hastings Dam
89°F at Windom, Albert Lea, Winnebago, Winona Dam, Waseca, and St Peter
88°F at Austin, Zumbrota, and Elk River
87°F at MSP, Grand Meadow, Lamberton, Marshall, and Gaylord
The bottom dropped out of the humidity measurements on April 13th as well as many climate stations around Minnesota report RH values ranging from only 12 to 18 percent. The National Weather Service had Red Flag warnings for much of the southern part of the state.
Interesting trivia note for April 13th at 5pm CDT, MSP reported 87°F with relative humidity of 15 percent, while Phoenix, AZ reported 81°F with relative humidity of 21 percent.
The warming trend for Minnesota will end on April 14th (Friday), with a cooler than normal temperature pattern taking over, followed by near normal temperatures for much of the rest of the month.
Farmers and gardeners are anxious to get started with plantings, and even with the cooler temperature pattern in play there will be plenty of days to work outside the rest of the month.
Severe Weather Awareness Week: April 17-21:
It is that time of year to remind yourselves and family members about severe weather possibilities in Minnesota and how to be prepared. Minnesota Department of Public Safety: Homeland and Security Emergency Management provides a great deal of material to update your company or family members on severe weather safety and protocols (for flash flooding, lightning, hail, strong winds, tornadoes), and they also feature a Power :Point presentation on their web site. It is worth reviewing.
Weekly Weather Potpourri:
The next webinar presented by the Minnesota Climate Adaptation Partnership (MCAP) will be on April 18th at noon. It is titled “Adaptive Forest Management.” Dr. Lucia Fitts and Dr. Jamie Mosel will present their findings concerning tree species responses to climate change, and insights on adaptation plantings to help natural resource managers in the Great Lakes States identify best practices in adaptive planting. To find out more and register please go to the MCAP web site.
Tropical Cyclone Ilsa hit the western coast of Australia just before midnight on Thursday this week with rare Category 5 force winds (over 160 mph wind gusts), heavy rains and high surf. It was expected to cause a great deal of flooding and wind damage. Up to 15 inches of rainfall was expected for some areas. The BBC reported extensively on this storm.
The Weather Underground reported this week on the supercell thunderstorm that drenched portions of Ft Lauderdale, FL with 13 to 25 inches of rainfall on Wednesday and Thursday, smashing all records for a 24-hour rainfall. Official observers near Hollywood, FL reported over 18 inches, and near Plantation, FL over 15 inches. Airports, schools, and roads were closed during this once in a thousand year event.
MPR listener question:
Not to be a pessimist, but when was the last time the Twin Cities had measurable snowfall in May, and how often does this occur?
Answer:
Dread the thought! After the slight chances for snow flurries on Sunday, I see no further chances for snowfall over the rest of spring. The last measurable snowfall in May was in 2013, just 0.5 inches In nearly 140 years of Twin Cities climate history, measurable May snowfalls have occurred only 22 times.
Twin Cities Almanac for April 14th:
The average MSP high temperature for this date is 56 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 37 degrees F (plus or minus 8 degrees F standard deviation).
MSP Local Records for April 14th:
MSP records for this date: highest daily maximum temperature of 89 degrees F in 2003; lowest daily maximum temperature of 30 degrees F in 2018; lowest daily minimum temperature of 18 degrees F in 1928; highest daily minimum temperature of 64 degrees F in 2003; record precipitation of 1.56 inches in 1983. Record snowfall is 13.6 inches also in 1983.
Average dew point for April 14th is 31°F; the maximum dew point on this date is 61°F in 1976; and the minimum dew point on this date is 4 degrees F in 2014.
All-time state records for April 14th:
The state record high temperature for this date is 94 degrees F at Benson (Swift County) in 2003. The state record low temperature for this date is -5 degrees F at Roseau (Roseau County) in 1950. The state record precipitation for this date is 2.95 inches at Northfield (Dakota County) in 1886. Record snowfall is 16.0 inches also at Farmington (Dakota County) in 1983.
Past Weather:
Fast-moving strong thunderstorms dropped 1.5 to 3.0 inches of rainfall across portions of eastern Minnesota on April 14, 1886, compounding the already wet conditions from spring snow melt. In southeastern Minnesota both the Cannon River and Vermillion Rivers flooded.
April 14, 1950 was the coldest in Minnesota history with many climate stations reporting single digit low temperatures. Portions of Roseau, Kittson and Beltrami Counties recorded subzero morning low temperatures and afternoon high temperatures remained in the mid 30s F.
A late season winter storm brought a good deal of snowfall to Minnesota on April 14, 1983. Heaviest amounts ranging from 6 to 15 inches were reported from eastern Minnesota, where some schools were closed. MSP recorded a record 13.6 inches, while Faribault reported 17 inches, and Hastings 19 inches.
Word of the Week: Vectopluviometer
This is a special type of rain gage whose characteristics can be inferred from the name: vecto referring to speed and direction, pluvio is the Latin for rain, and meter meaning to measure. Thus, this type of gage accounts for the inclination and direction of falling rain. Two types have been used: one type is a recording gage mounted to a windvane such that it always faces into the wind and catches rainfall coming from that direction. Another type is a series of four gages each oriented to a cardinal compass direction (E,W,N,S), such that the gage oriented most parallel to the trajectory of falling rain drops will capture the most water.
In case you are interested falling rain drops in April most commonly come from northwesterly, northeasterly or southeasterly directions.
Outlook:
Much cooler temperatures this weekend with widespread rains on Saturday, then a chance for rain/snow mixture early on Sunday, perhaps all snow in northern areas. Drier Monday and Tuesday with cooler temperatures. Chances for rain return late Tuesday into Wednesday as temperatures moderate towards normal.
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