May and Spring 2020 Saint Cloud Weather Summary

Dry Spring Characterized by Handful of Heavy Rain Events

May and Spring 2020 Saint Cloud Weather Summaries

May continued the four-month trend of mainly drier than average conditions in central and northern Minnesota. The May rainfall at the St. Cloud Municipal Airport was 1.05 inch, 1.90 inch below average. This marks the 9th driest May in St. Cloud records and the driest since 1976.

This dry trend began in February. During that four-month period, St. Cloud has picked up only 4.34 inches of precipitation, more than 3 inches below the average of 7.66 inches. This slowdown of precipitation from the fast snow start (37.5 inches of snow through January; 9.0 inches above average) was crucial to easing the potential for snowmelt flooding in most of Minnesota, except in the Red River Valley. It also has helped the water table return closer to average across central and southern Minnesota, which had near record precipitation last year. However, northern Minnesota has been not only dry in 2020, but was also relatively dry in 2019.

Not only has rain been relatively rare over the past four months, but it also has come during infrequent large rainfall events. The table below shows that the St. Cloud area has received more than 70 percent of its total precipitation in three large events over the past four months. The largest one of these was the heavy rain of March 28-29, which produced over 1.7 inches of rain. On April 27 and 28, a steady rain produced three-quarters of an inch over the two days. This accounted for over half of the April rainfall, mainly because central Minnesota missed the southern Minnesota heavy snow event of April 12-13. In May, a storm that produced two and a half to four inches of rain in southern Minnesota dropped 0.69 inch in St. Cloud. Overall, these three events produced 3.15 of the 4.52 inches of precipitation since February 1. However, that has been more than 3 inches below average.

Another measure of the infrequency of recent rainfall is that there have been only 10 days since February 1 with at least 0.10 inch of rain or more in St. Cloud. This is the fewest number of February-May days with at least 0.10 inch since 1934 (tied for the record lowest with 1926).

The meteorological spring (March 1-May 31) had only 4.36 inches of precipitation, more than two and a half inches short of the 7.07 inch average. That marks the 19th driest spring of 123 years on record.

The dry weather came with some cold periods during the first half of May, but there was some major warming late in the month. The St. Cloud average May temperature was 56.0 degrees, half a degree colder than average. The cold period produced a pair of 27 degree lows on May 9 and 12. These were the last St. Cloud frosts of the year. The last date was right near the median of May 10, but having a temperature drop below 28 degrees was unusual since the median last freeze date is April 29.

After being close to right on time with the first 50-degree, 60-degree, and 70-degree highs of the spring, St. Cloud had to wait quite a while for that first 80-degree high. It finally occurred on May 25 and was followed by an 83-degree high on May 27. Still, the month closed by failing to reach 70 degrees on two of the last three days of the month.