June 2012 Saint Cloud Weather Summary

Continued Record Warmth, But Drier Just in Time

June 2012 Saint Cloud Weather Summary

For the ninth consecutive month, St. Cloud, MN posted a monthly average temperature more than three degrees above the normal value. The St. Cloud Regional Airport averaged 68.8°F for the month of June. That's 3.2°F warmer than the average June temperature. While this June temperature ranks only as the 21st warmest out of the 131 Junes on record, it was warm enough to continue the incredibly warm period begun last June. There have now been 13 straight months with an above average temperature and 9 consecutive months.

Record Warm Heating Year (July-June)

The 2011-2012 heating season, defined as between July 1 and June 30, the 12-month average temperature of 48.3°F was 6.0°F warmer than the 1882-2012 average (gray dashed line) and ranks as the warmest heating season temperature in St. Cloud records. As was the case for the June-May 12-month period, the 2011-2012 heating season was well warmer than the previous record of 46.7°F in 1920-1921. Note that this past winter (Dec-Feb) and spring (Mar-May) also either tied or broke the warm record.

I do not know if St. Cloud has set a record low for heating requirements. That is measured by heating degree days. It is possible, because of the high average temperature. The total number of heating degree days for 2011-2012 was 6746, nearly 1800 lower than the average of 8532. This means that the demands on heating was 21% lower than the usual. (The State Climatology Office notes that the Twin Cities did set a record low for heating degree days.)

However, June 2012 was less extreme than May. While the high temperature broke 90 degrees three times, no temperature broke a daily record and all were cooler than the 94 degrees set on May 18. The dew points were high at times as well, producing 10 low temperatures of 60 or milder, but didn't yield any high temperatures in the 70's.

And, there was a bit of a cooler period. Between June 11 and June 26, the high temperature was only 85 or warmer twice. This trend mirrored last June, when the temperature hit 101 on June 7, but spent the next three weeks not reaching 80 degrees.

Below Normal Rainfall As St. Cloud Catches Edges of Major Flood Events

However, the biggest change from May was a slowing down of the heavy rainfall rate, even though this did not extend to other parts of Minnesota. The June St. Cloud rainfall was 2.36 inches, 1.81 inches less than the average of 4.17 inches. There was even a break in the April-May rainfall that produced 12 straight days without measurable rainfall between May 29 and June 9 and another 10 days without measurable rainfall to finish the month.

Still, June 2012 will be recorded as producing two major floods, one from Northfield through Cannon Falls on June 14, and the other the historic Northeastern Minnesota flood of June 19-20 that produced damage in the tens of millions of dollars from Two Harbors and Floodwood through Duluth, Jay Cooke State Park, and into the lower St. Louis River and Upper Mississippi River valleys.

Still 6 Inches Above Normal for Past Three Months

St. Cloud only got some of the rainfall from these two devastating events, picking up 0.69 inch during the June 13-14 rain event and 0.71 inch during the June 19-20 event. However, this comes at the tail end of three incredibly rainy months. Between April 13 and June 20, the St. Cloud Regional Airport picked up 13.69 inches of rain, more than six inches over the 7.42 inch period average. This has been part of a statewide trend that has produced 12-22 inches across the southeast two-thirds of Minnesota since the start of the growing season.

These heavy rain outbreaks also produced "conventional severe weather" in the form of large hail and straight-line damaging winds. On June 10, there was hail up to nickel-sized and downed trees from straight line winds in Avon, Rice, St. Stephen, and St. Joseph. On June 14, there was some large hail in Richmond and St. Cloud from a morning rush hour storm. On June 17, winds gusted up to 77 MPH in Cosmos.

The June 19 storm also produced "conventional severe weather" in the Minnesota River Valley to the west and south of St. Cloud saw straight line wind damage with gusts up to 45 MPH in Redwood Falls and 83 MPH in the Twin Cities.

Besides the extreme flood damage in parts of northeastern and southeastern Minnesota, the heavy rain has created high water in many lakes and fast-moving flow in several rivers. The high water has overwhelmed several septic systems, so swimming has been frowned upon. And, the huge inflow has deposited a large amount of silt into Lake Superior. On the other hand, the prominent waterfalls of northeastern Minnesota and other parts of the state have been even more spectacular. And, the heavy rainfall, where it didn't flood, has recharged the soil moisture, something needed after last year's dry second half of the growing season.

On the other hand, northwestern Minnesota has been mostly missed by these storms, so most of the Red River Valley, Red Lakes and Lake of the Woods areas are running 2-4 inches below normal for the year so far.

The reason for all of this rain is that Minnesota has been mostly just on the cool side of a persistent storm track across the Northern Plains and Great Lakes states. The occasional flow of very moist air into storms along this track has produced a series of large, slow-moving rainy weather systems during the past three months. Note the area from eastern Nebraska across Minnesota as one of the areas of heaviest rainfall during the past 30 days with other areas across the northern tier of states to the Northern Rockies, across northern Maine, and in Florida, where Tropical Storm Debby dumped 10-25 inches of rain this month. On the other hand, note the lack of rain from the High Plains westward through Wyoming, Colorado, Utah, and points south. This dryness, combined with a low snow season in the central and southern Rockies and the major heat wave that has developed from Colorado to the Carolinas (daily highs in the 100s and 110s; see last ten days, for example) has produced one of the worst fire seasons on record in the Rockies. There have been 384 high temperature records for the month of June with thousands of daily record highs set. This combination of hot and sticky air moving over cooler air at the ground produced one of the most widespread straight line damaging wind events in US history on Friday.

Northern Edge of Heat Through July 4 Week

Some of the long range forecasts are trying to show some relief for at least the eastern heat as July wears on. However, for the next week at least, the searing heat is expected to continue with St. Cloud being closer to the hottest temperatures and having a shot at several days over 90. This very hot air is also very dirty with ozone levels high to the east of the Mississippi (and more created by rush hour traffic), smoke from the Rockies fires, and additional smoke from large fireworks displays this week will make breathing outdoors difficult at times.

    June 2012 Statistics