SUBJECT: It was hot, but why wasn’t it a record? July 2001 St. Cloud weather summary The July 2001 temperature statistics from the Saint Cloud Airport showed that the average temperature of 72.0 degrees was just short of two degrees above normal. Both the average low and the average high temperature were almost two degrees above normal. There were also 8 days with a high of 90 degrees or higher, nearly double the normal amount. This month raised the total number of 90 degree highs to 13 days, about 2 days higher than normal for the year. However, the warmth was not unusual for the month of July. July 1999 was even warmer with an average temperature of 72.6 degrees. There were 9 days with a high of at least 90 degrees during July 1999. There were no temperature records set in July 2001 and it was far from the hottest July in the 120 years of Saint Cloud records. So, why does it seem like July 2001 was so extreme, especially in light of the death of Kory Stringer? The most probable reason is that we have become accustomed to cooler than normal summer weather. The decade of 1991-2000 had the coldest average summer temperature of the twelve decades on record for Saint Cloud. Of the summers since 1989, only 3 of the 11 summers (1991, 1995, 1999) have had above normal temperatures. While the extreme dew points of the last two days of July 2001 (middle to upper 70’s) were unusually oppressive, there have also been much longer periods of extreme heat and humidity in both July 1995 and July 1999. The July 2001 rainfall in St. Cloud was 2.10 inches, more than an inch below normal. Most of the rainfall fell in the last 10 days of July with 1.78 inches falling at the airport (and 2.32 inches at Saint Cloud State University). Therefore, the month from June 22 through July 21 was extremely dry with only .32 inch falling during a period when at least an inch of rain per week is required to keep crops and lawns healthy. The above normal temperatures during this period made this rainfall deficit even worse, by increasing evaporation. July 2001 was the second consecutive month in Saint Cloud with below normal rainfall, accounting for more than a 2.4 inch shortfall. However, the growing season rainfall (April 1 – July 31) is still more than 4 inches above normal in Saint Cloud. Rainfall relief has also occurred in portions of central Minnesota. While the rainfall deficit over the past 4 weeks is about an inch in Saint Cloud, rainfall has been near normal over the past month along a corridor just to the north of Saint Cloud, from Fergus Falls through Alexandria, Little Falls, to Hinckley. On the other hand, the US 12 corridor missed much of the rain during the past 10 days, so rainfall deficits over the past 4 weeks run from an inch in Willmar to over 2 inches in Hutchinson and Redwood Falls. JULY STATISTICS JULY 2001 NORMAL TEMPERATURE ( F) Average high temp 84.4 82.6 Average low temp 59.6 57.6 Average temp 72.0 70.1 Hottest high temp for the month 95 on the 9th, 31st Coolest high temp for the month 64 on the 2nd Warmest low temp for the month 77 on the 31st (broke record; see below) Coolest low temp for the month 46 on the 5th DAILY RECORD TEMPS Daily record warm low 77 on the 31st (old record: 74 in 1995) Daily record warm mean 86 on the 31st (old record: 85 in 1995) Days with highs of at least 90 8 4.7 Total for season 13 10.7 PRECIPITATION (IN) Total for month 2.10 3.11 Maximum daily amount .84 on the 27th TOTAL RAINFALL (IN) June 22 - July 31 2.10 4.49 April 1 – July 31 17.64 13.23 mcwg@soils.umn.edu URL: http://climate.umn.edu/doc/journal/stc0107.htm Last modified: August 2, 2001
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