June 2020 Saint Cloud Weather Summary

Hot Times in June (For a Change), But Is It a Drought?

June 2020 Saint Cloud Weather Summary

Hot summers have been relatively rare in central Minnesota since the heat wave and drought in the second half of the 1980's. While the average winter temperatures since 1996 have frequently been among the warmest on record, summers have rarely reached the level of 1988 or the 1930's, with only the later years of the 2000's getting close.

12th Warmest June, Warmest Since 1988

However, the summer of 2020 is off to a very warm start. June, the first month of meteorological summer, ended up being 4.6 degrees above average in St. Cloud. The average temperature was 70.2 degrees, only 0.1 degree short of 10th place, making June 2020 the warmest June since 1988. While June of 1988 had extremely hot high temperatures (11 highs of at least 90 degrees, 5 highs of at least 100 degrees, and half of all of the 100 degree highs recorded since 1950), June 2020 produced 4 highs of at least 90 degrees, including the record-setting 93 degree high on June 1. There were 4 highs of at least 90 degrees, the most since June of 1996. The hottest high temperature of the month, 96 degrees on June 8, fell two degrees short of the record, but was only St. Cloud's second high temperature above 95 degrees since 2011.

Where June 2020 outdid June 1988 was in the low temperatures. The June 2020 average low was 57.5 degrees, 3.6 warmer than average, and 2.5 degrees warmer than the June 1988 average. These mild overnight temperatures included 13 lows of at least 60 degrees, and a low of 73 degrees on June 8. That set a record warm low for the day and was the warmest low in St. Cloud since August 25, 2013 (74 degree low). The warm lows also contributed to 3 record average temperatures (average of high and low temperatures) being tied or broken.

Dryness Continued...

The drier than average conditions that have marked 2020 continued in June. The St. Cloud Municipal Airport received 2.63 inches of rain in June, 1.54 inches below average. For the growing season (since April 1), St. Cloud is 4.70 inches short (total 4.99 inches; average 9.69 inches) and, for all of 2020, St. Cloud is 4.22 inches short (total 8.24 inches, average 12.46 inches).

...Eased in Spots by Late Month Rain

Once again, a large portion of the monthly rainfall fell in a concentrated period. Between June 28 and June 30, much of eastern Minnesota was affected by a slow-moving low pressure system that touched off heavy thunderstorms. There were 6-8 inches of rain from south central and southeastern Minnesota into the Twin Cities and a narrow strip of 6-9 inches of rain in southern Morrison County, including Little Falls. The St. Cloud Airport picked up 1.39 inch of rain on June 28 and 29. Without that late month rain, St. Cloud's January through June rainfall would have ranked as the 6th lowest first 6 months of the year. With that rainfall, St. Cloud has had the 19th driest first 6 months of the year.

Note that June rainfall widely varied in Minnesota (northwestern Minnesota picking up 10-15 inches of rain partly in a severe weather outbreak, while west central Minnesota and the Duluth area had under 2 inches. Even within Stearns County, total rainfall ranged from between 2 and 5 inches. For the growing season so far, growing season rainfall is less than 50 percent of the average in most of central, west central, and northeastern Minnesota, except in the strip that includes Little Falls. This lack of rainfall has shown up as drought conditions on the US Drought Monitor.

Drought Category Mitigated by Plentiful Ground Water From Last Year's Record Rains

But, the impact of any rain shortfall in central Minnesota is not as severe as depicted, because we are coming off the huge 2019 precipitation that broke records in many places, including St. Cloud. The deep soil moisture is still high due to that huge rainfall in most of Minnesota, except a strip from International Falls and the western Boundary Waters to Ortonville and Lake Traverse. The latest Minnesota Weekly Crop Summary rates statewide topsoil and sub-soil moisture as 88-92 percent adequate or surplus. Plants with shallow roots, like grass, are struggling at times, but any plant with deeper roots can tap the deep ground water supply. So, the area outlined in the US Drought Monitor of most concern is north central and west central Minnesota with less serious conditions in central Minnesota.

Precipitation Still Coming in Rare, Large Batches

Those shallow-rooted plants are also struggling since the precipitation is coming on relatively few dates. Once again, St. Cloud had more than half of its monthly rainfall in the big dose on June 28-30. The 1.39 inch on June 28 and 29 accounted for 53 percent of the monthly rainfall. The table below shows this trend continuing since the start of February. Four events, one in each of March and June, have accounted for more than 63 percent of the precipitation since February 1. The long periods between major rainfall can stress those plants, especially if we continue the hot trend, since evaporation is above average. For the average summer temperatures, the lawn needs about an inch per week, and that should be added early in the morning, when temperatures are coolest, so the evaporation of the water is minimized.

In general, this growing season has been everything that 2019 was not. Crops were planted on time since the soil was much drier and the warm weather has allowed good progress so far.

    June 2020 Statistics