August 2012 Saint Cloud Weather Summary

Yet Another Part of the Summer Dry

Saint Cloud Weather Summary for August 2012 and Summer 2012

Issued: Saturday, September 8, 2012 9:06 AM

Dry Spell Intensifies in August

The brown lawns and parched grass you see reflects the driest month St. Cloud has seen all year. The August rainfall at the St. Cloud Regional Airport totalled only 1.22 inches, 2.57 inches lower than the average. So, in August, St. Cloud caught a piece of the dry weather that has plagued northwestern and southern Minnesota for much of the summer. Rainfall deficits since mid-June are 4-5 inches in northwestern Minnesota and 5-8 inches in many portions of the southern half of Minnesota, so there are areas ranked in moderate to severe drought by the US Drought Monitor. The Mankato area actually represents an arm of the severe drought that continues to plague most of the Central and Southern Plains and did affect Missouri and Illinois before heavy rains from the remants of Tropical Storm Issac eased conditions a bit.

In central Minnesota, conditions are more complicated. Note that the rainfall shortfall documented by the State Climatology Office shows Rice being short by about 2 inches, but conditions drying out to as much as 5-6 inches below normal in Paynesville, Willmar, and Elk River. The wetter conditions towards Morrison County were caused by these areas catching the southwestern edge of the heavy June rainstorm that produced major flooding in Duluth, southern St. Louis County, and northern Carlton County.

The St. Cloud rainfall total is in the middle of the pack. Between June 1 and September 5, the Airport is 4.77 inches behind on rainfall (7.17 inches fallen, 11.94 inches average). The biggest parts of this shortfall were in June and August with actually near normal rainfall in July. All of this dryness comes on top of a very wet April and May when the rainfall total was 5.76 inches above average. That and the heavy June rainstorm covering part of the Upper Mississippi River Valley has kept the river flowing throughout the summer.

This marks the fourth year out of the past 5 with a significant dry spell that began sometime in the summer and only broke some time in the fall. Note that, in the 2008, 2009, and 2011 seasons, these short dry periods also ended up producing rainfall totals more than 4 inches below average. Each of those years had at least a hot July, which drove using of water through evaporation higher. Note also that the dry spell in 2009 lasted most of the growing season, so that the Mississippi River levels in St. Cloud droped to their fifth lowest on record.

These seasons have also led to some wildfire problems on warm and windy days during the dry periods.

However, the sobering part is that St. Cloud has much longer dry periods on record. From the fall of 1986 through much of 1989, St. Cloud endured three extremely dry years in a row. The total rainfall deficit from those three growing seasons combined was nearly eighteen and a half inches. Those years saw the crops dying out similar to all of the scenes in Missouri and Illinois this year and in Texas and Oklahoma last year. There is no question that this year's dryness in Minnesota hasn't reached that level, with the longest dry period in the Red River Valley which has put together two dry years.

None of this counts the Dust Bowl years of the 1930's, in which there were 10 straight poor growing seasons.

Average Temperatures Are Far From Average in St. Cloud Recently

After the sixth warmest July in St. Cloud records and 13 straight months of well above normal temperatures, August 2012 in St. Cloud finally broke the streak. The average temperature at the Saint Cloud Regional Airport was 67.8°F, exactly the average in the 1981-2010 period. And, it took a bit of warming to get it there. After hitting 93°F, the hottest temperature for the month, more seasonable air masses began to push into St. Cloud regularly. Since the air was so dry, high temperatures still remained near average (12 days with a high in the 70's during August 3-25), but low temperatures frequently dropped into the 40's. In fact, the first 21 days of the month averaged 64.8°F. The last 10 days of the month saw high temperatures climb more often into the 80's and low temperatures stay in the 50's or higher. The last month with a below average temperature was May 2011.

The normal August weather cost St. Cloud a chance to have one of the 10 hottest summers on record (since . The average meteorological summer (June 1- August 31) temperature was 71.0°F, 3.1°F above average, but only good enough for 11th place ........again!! It was still the hottest summer in St. Cloud since 1988. Note that the 1988 and 2011 summers are the only once since 1936 to break into the 11.

Still, it was much hotter not much further to the south. Minneapolis-St. Paul International Airport had its third hottest summer on record and Eau Claire had its 5th hottest. Minneapolis has had 30 days with a high of at least 90 degrees (tied for 9th most), while St. Cloud has only amassed 16 such days (one on Sept. 3). That St. Cloud total is still less than the 20 such hot highs St. Cloud saw in both the summers of 2006 and 2007.

What's Up Next?

September, on the average, has highs ranging from the upper 70's early in the month to the middle 60's by late in the month. Low temperatures drop out of the 50's to near 40 by the end of the month. Still, there has already been one 90-degree high during the month. Both 2003 and 2007 produced three 90 degree highs. On the other hand, St. Cloud should see its first frost of the year (average date of Sept. 22). We'll also see the leaves changing in northern and central Minnesota. With an El Nino current developing, the outlook for the winter season looks to be mild again, but we will be hard pressed to match last year's record warm winter.

    August 2012 Statistics

Summer (June 1-August 31) 2012 Statistics