Record Heat for Early June

Record Heat for Early June:

Heat has been the dominant signature of the weather pattern across Minnesota over the first 10 days of June. In fact, based on average temperatures reported from all the climate stations in the state it has been the hottest first 10 days of June in state history, with temperatures ranging from 11 to 14 degrees above normal for the entire 10 day period, and up to 23 degrees above normal on individual days. At least 35 climate stations have reported a maximum temperature of 100°F this week, with many overnight low temperatures remaining in the 70s F.

Dew points have gradually increased over the week from the 40s and 50s F to the 60s F and even near 70°F, making the Heat Index approach or exceed 100 degrees in places. Some Heat Index values ranged from 105 to 110 degrees F this week.

Within the Minnesota climate station network over 300 new daily warm maximum and warm minimum temperature records were set, including a reading of 98°F at International Falls on June 4th, the earliest date ever for such a temperature there. In addition, three new statewide warm maximum daily temperature records were set this week, along with two statewide warm daily minimum temperature records. These were:

June 4 maximum temperature of 101°F at Georgetown (Clay County)

June 5 maximum temperature of 103°F at Milan (Chippewa County)

June 7 maximum temperature of 104°F at Warren (Marshall County)

June 6 minimum temperature of 79°F at Sabin (Clay County)

June 10 minimum temperature of 79°F at La Crescent (Houston County)


There have been very few weekly periods in state history that have produced 5 or more statewide warm temperature records (February 1981, March 2000 and 2012, May 1934, June 1933, July 1936, August 1976, and September 1931, and December 1998). So it is likely this early Heat Wave of June 2021 will be long remembered.

Little rainfall fell this week, except in some parts of far northern Minnesota where over an inch of rainfall was reported. Gunflint Lake (Cook County) and Orr (St Louis County) reported over 2 inches of rain. The heat this week coupled with the absence of rainfall in most places has accelerated produced drought concerns over many areas of the state. According to the U.S. Drought Monitor portions of 6 Minnesota counties are in severe drought, and 55 counties are designated in moderate drought, with the rest of the state drier than normal, but not yet in drought. Some areas of southern and western Minnesota have received less than 50 percent of normal precipitation for the year so far. Further the outlook models show continued trend for hot and dry through most of the rest of the month. Many lawns are already showing signs of browning, and some tress are under stress as well.

More updates on the June Heat Wave can be found at the Minnesota State Climatology Office web site.

Weekly Weather Potpourri:

The Weather Channel reported this week that parts of Arkansas and Mississippi received up to 20 inches of rainfall this week causing widespread flash flooding in many areas. Rohwer, AR reported 20.57 inches with nearly 10 inches coming on June 9th. Charleston and Lambert, MS received over a foot of rain


A recent study from Imperial College scientists shows that transmission of COVID-19 virus varies seasonally, but warmer temperatures alone are not enough to prevent transmission. In this study “results show that summer weather cannot be considered a substitute for mitigation policies, but that lower autumn and winter temperatures may lead to an increase in transmission intensity in the absence of policy interventions or behavioral changes.”

MPR listener question:

With the Twin Cities reporting a record number of consecutive days with high temperatures of 90°F or greater this month (9 days), we were wondering what is the statewide record for such a streak of days in June, and what is the overall records streak for summer?

Answer:

Indeed, the consecutive days over 90 degrees in the Twin Cities during the month of June is exceptional. There were 14 such days from July 5 to July 18, 1936 which is the summertime record in the Twin Cities. The record amount of consecutive days with 90°F or above in June is from Milan (Chippewa County), MN with 16 such days (June 15-30, 1933). The record for summertime is 25 such days at Beardsley (Big Stone County), July 4 to July 28, 1936.

Twin Cities Almanac for June 11th:

The average MSP high temperature for this date is 78 degrees F (plus or minus 7 degrees F standard deviation), while the average low is 57 degrees F (plus or minus 7 degrees F standard deviation).

MSP Local Records for June 11th:

MSP records for this date include: highest daily maximum temperature of 96 degrees F in 1956; lowest daily maximum temperature of 55 degrees F in 1877; lowest daily minimum temperature of 40 degrees F in 1903; highest daily minimum temperature of 74 degrees F in 1956; record precipitation of 2.58 inches in 1975. No snowfall has occurred on this date.

Average dew point for June 11th is 55°F; the maximum dew point on this date is 71°F in 1953; and the minimum dew point on this date is 31 degrees F in 1962.

All-time state records for June 11th:

The state record high temperature for this date is 102 degrees F at Fairmont (Martin County) in 1933. The state record low temperature for this date is 24 degrees F at Fort Ripley (Crow Wing County) in 1877. The state record precipitation for this date is 5.31 inches at Camp Norris (Lake of the Woods County) in 2002. No snowfall on this date.

Past Weather Features:

June 11, 1877 brought April-like weather to many parts of Minnesota. Low temperatures were in the teens and twenties across northern counties. Duluth saw a high temperature of only 42°F, and in the Twin Cities the afternoon temperature only reached 55°F.


June 9-11, 2002 brought a series of strong thunderstorms to northwestern and north-central Minnesota. Record-setting rainfall amounts were reported with as much as 14.55 inches near Lake of the Woods. Widespread flooding occurred on the rivers and streams in the area.  The Minnesota State Climatology Office offers a narrative review of these storms.

Outlook:

Cooler on Saturday with lower dew points. Then warmer again on Sunday. Continued warm and dry next week with daytime temperatures from the mid 80s F to mid 90s F. Slight chance for rain and thunderstorms Wednesday and Thursday, especially in northern areas of the state.