June 2023 Saint Cloud Weather Summary

5th Warmest June Since 1933

The hottest air on the continent dominated much of the month across the southwestern and south central US. The edge of that heat has successfully pushed into Minnesota frequently in June 2023. That was certainly true during the second half of June. There were a total of 7 days with a high of 90 degrees in the past 2 weeks (see red line on the 30-day graph of St. Cloud temperatures and moisture from MesoWest). Along with this heat, we have had persistent dew points from the upper 50's into the middle 60's (blue line on the 30-day graph of St. Cloud temperatures and moisture from MesoWest). That is wuss territory for heat and humidity in east Texas and Florida, but is at least noticeable to uncomfortable in Minnesota. This kind of lingering moisture was also present in much of June. Because of the persistent high dew points, 21 days had a low no cooler than 58 in the past month. Add in the 90's seen from the end of May into the start of June and we have some of the reason for St. Cloud's 71.5 degree June average temperature, which ended up being alone as 5th warmest June in St. Cloud records (hottest since 1933).

Extreme Daily Temperatures Not Seen

While there were 8 June 90-degree highs, none were hotter than 92 degrees. That's in contrast to June 2021 with 8 highs between 94 and 98 degrees and June 2022 with only 4 90-degree highs, but 2 of them were 99 and 101. 2021 and 2022 temperatures pepper the June records, while June 2023 only tied two record warm lows on June 2 and 3.

Driest May-June in St. Cloud Records; 3rd Driest June

The dominant highs, both to our south late in the month and near the Great Lakes or Canadian Prairies earlier in the month, have made any thunderstorms spotty east of the western and central Dakotas (yellow areas on the NWS Minnesota 60-day rainfall map). Much of northern and central Minnesota has picked up less than 4 inches, light green or blue in that period. We are supposed to get more than three and a half inches of rain in both May and June on the average. That's why the combined May-June St. Cloud rainfall of 1.54 inch is 5.87 inches below average, ranking as St. Cloud driest May-June on record. That's easily drier than May-June 1900, the second driest with 2.25 inches, and May-June 1988, the third driest with 2.27 inches. There have been only 3 May-Junes with less than 3 inches total.

In June alone, St. Cloud has picked up 0.67 inch, which ranks as the third driest June in St. Cloud records. Only 1988 (0.05 inch) and 1893 (0.54 inch) had drier Junes.

It Was the Snowiest of Times; It Was the Driest of Times

However, the dry period is only since the snow season ended. There has been a dizzying reversal of precipitation from the cold season to the two months. The record-setting snowfall during our cold season (with some rain and ice at times) accounted for more than a 6-inch moisture surplus. That has turned to a nearly 6 inch deficit the past two months.

Graphics courtesy of Ross Carlyon, NWS Twin Cities climate guru

How can we have been buried with snow all winter and have a water shortage? The trouble is the warm air has a higher capacity to store water vapor than cold and it's by a lot. Note that the average precipitation for the entire six months from November to April is 7.86 inches, with December, January, and February averaging less than an inch. So, the extreme snowfall only produced 2-3 inches of water per month. But, in May and June, we average more than three-quarters of an inch a week. On top of that, the warmer than average temperatures cause evaporation and transpiration (water vapor used by plants for food making) to go way up, so there is far more water loss than in the cold season. So, we can quickly offset a snowy winter with a couple of dry months.

Major Air Quality Problems Also A June Factor

The month of June will also be remembered for the air quality issues, both from ozone during the hottest days and from Canadian wildfire smoke when the steering winds were from the north. There were two major smoke outbreaks, one peaking on June 14, during which Minneapolis-St. Paul's air quality index ranked among the worst in the world, and another outbreak on June 27-28 (see June graph of St. Cloud worst daily Air Quality index from iqair.com; scroll to bar graph and set for daily), during which southeastern Minnesota shared some of the worst air quality in the world with Wisconsin, Detroit, and Chicago.

High pressure has also played a major role in the large fire outbreaks still over both the Canadian Prairie Provinces and Ontario and Quebec (see orange circles denoting incidents on the firesmoke.ca website). The split jet stream that produced our snowy cold season, with storms getting in from both Canada and occasionally from Rockies, often had high pressure near the Canadian Rockies, reducing the amount of precipitation. The spring highs brought warmer than average air, creating the potential for wildfires.

We'd Better Survive Flash Droughts

When referring to the latest drought statistics from the US Drought Monitor, I always feel a bit squeamish about the terminology of "severe" or "extreme" drought for a two-month rain shortfall. Yes, lawns are brown, crops need rain (typically an inch a week during the growing season) and the streamflow in rivers that were flooding in March and April, is down to the lowest 25 percentile in parts of northern and central Minnesota. However, this doesn't reflect the huge drop in ground water that occurs in multi-year droughts, which are the ones I consider severe or worse. 1988 was more typical of a prolonged multi-year drought, covering 1986-1989 in Minnesota On the National Climatic Data Center's historic drought monitoring website, you can set the period to March 1988 through September 1989 and see how widespread the red and especially purple (most extreme category of drought) lasted across the northern tier from the eastern Rockies into the Great Lakes. That drought was more similar to the "Dust Bowl" days of the 1930's (try 1931, 1933 through 1934, and 1936 through 1937) or the prolonged snow and rain shortage in the Intermountain West that lasted several years (run the past few years) and still have reservoirs on the Colorado River well below average.

I know June 2023 isn't up yet, but there's only one Nebraska division in purple in May 2023. Now, the data is better than 45 years ago, so the US Drought Monitor is picking up more localized areas of rain shortfall. Certainly, these short-term "flash droughts" can get low stream levels, drop some lake levels, and stress crops. Sometimes, they can be as severe as the longer term droughts, like the shortage in parts of west central Minnesota and the Minnesota River Valley from last summer (more than 10 inches in places like Redwood Falls). However, these conditions are not nearly as severe as the historic prolonged serious droughts. And, those droughts are in our weather records, so a multi-year will be return at some point.

This summer has the potential to produce a prolonged heat wave and drought in the south central US. The long-range forecasts show a persistent high across some part of the southern US well into July. If that large heat reservoir persists, Minnesota might see more hot air intervals, although the one that ended the month looks to end by the middle of this week. Also, there is the potential for some heavy rainfall on the northern fringe of where the hot air sets up, as the hot and steamy air gets far enough to the north for weather systems to lift it. Whether that will be in Minnesota remains to be seen.

    June 2023 Statistics

 Last Updated: July 2, 2023