Going into the last 10 days of August, the St. Cloud Regional Airport had picked up only 0.30 inch of rain, which would have been the driest August in St. Cloud records. The difference since May 1 was 7.91 inches (6.03 inches actual, 13.94 inches average), the biggest departure from average of any period. However, the St. Cloud Airport picked up 3.33 inches of rain from August 20 through August 29. The average for the entire month of August is 4.00 inches. Parts of central and southern Minnesota picked up from 2 to 8 inches of rain during this period.. With the August rainfall of 3.63 inches, the May through August shortfall is now 5.65 inches (9.39 inches actual, 15.01 inches average), the 9th driest May through August in St. Cloud records and the driest since 1976.

While portions of western Stearns and eastern Pope County have now caught all the up to average, since these areas have seen over 8 inches of rain in the past two weeks, areas to the south and east of St. Cloud are still more than 4 inches behind over the past 90 days with some parts of Wright County through Mora more than 6 inches behind. Also, much of northern Minnesota is more than 6 inches short on rainfall, including the northeastern part of Minnesota, which has the large wild fires.

The effect of the late August rain can be seen in the change of the US Drought Monitor between August 31 and August 24 (set date tabs on the comparison and the state to Minnesota). All of the extreme drought (red) across central and southern Minnesota has been reduced to moderate (tan) or severe (dark brown) thanks to additional rain. In addition, the level of the Sauk River in St. Cloud has climbed from 0.24 feet (second lowest on record) before the rain to 1.18 feet. The Mississippi River in St. Cloud has climbed from 3.50 feet (second lowest on record) before the rain to 4.1 feet. Most rivers and streams in central Minnesota are either in the lowest 10-24 percentile (orange) or the near average (green) category on the USGS Minnesota streamflow map. Nearly all streams in central Minnesota were in the lowest 10 percent (red) before the rain. That still is the case from Brainerd northward.

Minnesota top soil moisture was ranked as 84 percent short or very short on August 22, but only 48 percent short or very short as of August 29. 69 percent of sub-soil moisture is still ranked as short or very short, so a lot more rain is needed.

There were two days with at least an inch of rainfall, 1.41 inch on August 24 and 1.21 inch on August 28. Only the smaller amount on August 28 was enough to break the daily record rainfall of 0.85 inch, set in 1940. That's because the old record for August 28 was a relatively easy record to break; all other days between August 21 and 30 had records of at least one and a half inches, with all but one over 2 inches.

August finished a degree warmer than average (68.7 degrees, 1.0 degrees above average). There were 5 more days with a high of at least 90 degrees, bringing the summer 2021 total to 21 days. That's the most 90-degree days, since 1988, the center of the last prolonged drought in 1986-1989. There were 33 highs of at least 90 degrees in 1988 with 7 of those highs of at least 100 degrees.

There were no more lows of at least 70 degrees. The summer of 2021 had 4 lows of at least 70 degrees, the most seen since 2013.

The August average high was 3.6 degrees warmer than average. However, the dry conditions meant that the low temperatures were dictated by the dew points on clear and calm nights. So, there were 7 lows of 52 degrees or cooler. The August low was only 1.3 degrees warmer than average, keeping St. Cloud from a top 10 warm August.

Meteorological summer (June 1-August 31) in St. Cloud produced an average temperature of 71.1 degrees. This tied the summer of 1932 for the 10th warmest summer in St. Cloud records. 1988 (tied for 4th place) is the only other summer since 1940 to rank among the 10 warmest.

The summer precipitation was 7.09 inches, 4.26 inches below average and the 13th driest summer in St. Cloud records.

    August 2021 Statistics

Summer (June 1-August 31) 2021 Statistics