August 2004 Saint Cloud Weather Summary

Subject: Saint Cloud Weather Summary for August 2004 and Summer 2004

Saint Cloud's Coldest August Since 1886

Tied for Fourth Coldest Summer on Record

     If you didn't like July 2004, you really hated August 2004. The upper-air flow that brought cool air frequently into central Minnesota in July became stronger and more persistent in August. For this reason, the average August temperature at the Saint Cloud Municipal Airport was only 62.3°F, 4.9°F colder than normal. This reading made August 2004 the second coldest August in 123 years of Saint Cloud temperature records. (Ten coldest/warmer Augusts are here.) The only August that has ever been colder was in the early settlement days of 1886 when the average temperature was more than three degrees colder than this past month. The August average high of 73.8°F and the average low of 50.8°F are the normal temperatures for September third and fourth.

     There were two major cold surges in August 2004 statewide. The first cold air surge was on August 9-15, and was marked by a cold air mass that had a lot of residual moisture. (See August 2004 daily highs and lows here.) The persistent cloud cover allowed Saint Cloud to tie or set three daily cold records, including the high of 57°F on August 10, tying August 21, 1966 and August 23-24, 1940 for the second coldest Saint Cloud August high temperature. The only colder high temperature was 55°F, set on August 25, 1958. (See August daily temperature records here.) The skies slowly cleared during the last 3 days of the outbreak, but clear skies allowed low temperatures to approach record lows in the 40's. In all, Saint Cloud had 5 days averaging more than 10 degrees below normal. While Saint Cloud fell two degrees short of its coldest August high temperature, International Falls had a high of only 49°F on August 10, setting a new August record for the coldest high temperature and marking only the 6th time the high temperature failed to reach 50°F in their history. (See NWS Duluth summary on this record.) Embarrass and Tower had low temperatures drop into the upper 20's, producing daily Minnesota record low temperatures on several dates.

    The second cold outbreak, on August 18-21, had drier, but colder air. For this reason, Saint Cloud high temperatures were able to climb to the upper 60's to low 70's, but plunged into the 30's on three straight mornings. (See August 2004 daily highs and lows here.) Four daily cold temperature records were set during this period (See August daily temperature records here.), plus the coldest August low temperature of 33°F was tied on August 21. The only other August day that has had a low of 33°F was August 31, 1974. While the official Saint Cloud thermometer escaped its first August frost ever, many neighboring cities and townsto the north and east of Saint Cloud had sub-freezing temperatures, including Brainerd, Pierz, and Garrison. In addition, many personal accounts from the rural areas to the north and east of Saint Cloud confirmed a frost and temperatures in the upper 20's. (See statement on cold August 19-21 lows from the State Climatology office). On this morning, Hibbing managed to set its coldest August low temperature in history with a reading of 27°F. The previous night, frost and, in some places a freeze with lows in the middle to upper 20's, hit the northern Red River Valley and other non-forested parts of northwest Minnesota. During this period, Embarrass again set three statewide daily record lows with the coldest being 20°F on August 21.

   Unlike many months of recent years, the cold statistics for August 2004 were representative of the entire month's weather. The high temperature never got above 83°F. The only high temperature that was more than 4°F above normal was Tuesday's (August 31st) 82°F, 8°F above normal.

     The cool August helped drag the meteorological summer (June 1 - August 31) average temperature to 64.4°F, 3.0°F colder than normal. So, summer 2004 tied the summer of 1945 as the fourth coldest summer in the 123 years of Saint Cloud temperature records. (Ten coldest/warmer summers are here.) (Note that the SCSU monthly temperature statistics are more complete than those of the NWS, so tied for 4th is the correct rank). In the past 90 summers, only the summer of 1992, the coolest summer on record, has been colder. While there have been only 4 highs of at least 90 degrees during this warm season, and one of these days was in April, there have now been 12 cold records set in July and August. There are now links to other Minnesota cold season statements including the coldest August and Summer 2004 on record at both Alexandria and International Falls, the 5th coldest August and 11th coldest summer in Duluth, the 6th or 7th coldest, at the bottom of this summary. Note that these links will move from temporary pages to permanent pages during the first couple of days of September.

    One weather statistic that has been underpublicized during the cool summer is the relative lack of rainfall. In August, only 1.64 inches fell at the Saint Cloud Regional Airport. This total, more than 2.3 inches below normal, was the 20th driest August in Saint Cloud history. Moreover, the summer 2004 rainfall ended up being just about three inches below normal. The growing season rainfall (April 1 - August 31) was very close to normal (16.82 inches of rain compared to the normal of 16.88 inches). Much like last year, most of the rain fell during a relatively short period. Between May 16 and June 16, 9.72 inches of rain fell, accounting for 58% of the warm season rain. Without the rainfall from those 32 days, this warm season has been more than 5.7 inches below normal. In fact, the monthly rainfall statistics through August look a lot like those from last year. The cause of this year's dryness has been the persistent northwest flow of weather from northern Canada. True moisture from the Gulf of Mexico has been pushed much further south than normal. So, when fronts come through, few of them have had access to enough moisture to produce widespread heavy rainfall. Given the sporadic nature of thunderstorms, areas have been frequently missed.

    The dry August has allowed the dry conditions in the north central part of the state to greatly expand over the past two months. The August 30 growing season precipitation map from the Minnesota State Climatology Office shows that the worst conditions remained from the northern half of Morrison County to Leech Lake and eastward through Grand Rapids and the Iron Range, similar to the area that has been short of rain all year. However, this dry area, with less than 80% of the normal rainfall, has spread into the Bemidji, Bagley, and Park Rapids. In addition, the area of slightly below normal rainfall has extended southwestward from Wheaton and Ortonville northwestward through Alexandria and Saint Cloud. In all of this area, rainfall has been short over the past month. However, conditions are not as bad as last year because of the cooler weather, which limits moisture loss due to evaporation.

    What are the consequences of the cool, dry weather this summer, aside from the complaints I get? The first consequence is the potential crop loss. The cool, rainy May and June delayed crop germination and the early frost has damaged much of the crops in northwestern Minnesota. Crop damage from the August 19-21 cold period is still being assessed in north central and central Minnesota.

     The cool conditions will apparently be good for the foliage, increasing the likelihood of leaves turning brightly at the same time. The negative factor is the dry conditions, tending to have leaves shrivel. Based on recent weather, there will be spectacular foliage viewing potential except possibly in the dry areas of north central Minnesota. However, that does not include the North Shore which has had plenty of rain.

     Finally, the dry conditions is of some immediate concern due to the hot and windy conditions expected later this week. This morning, these conditions are producing a red flag warning for a high forest fire danger in western North Dakota. While we won't get as hot, the combination of winds and heat will increase fire danger into the high to very high category on the Minnesota DNR wildfire forecast on Thursday and Friday.

    Ironically, weather conditions for the first few days of September are expected to approach levels we haven't seen for most of the summer. According to my latest forecast, high temperatures will be near normal on Wednesday, then well above normal at least on Thursday and Friday with a chance of 90 degrees for the first time since July 21 on both days.

Links to Other Cold August and Summer Statements

• NWS Minnesota Statements on August and Summer Records as they come in (9/1/2004)
• NWS Wisconsin Statements on August and Summer Records (including Rochester; 9/1/2004)
• NWS South Dakota Statements on August and Summer Records (9/1/2004)
• Cold August in Grand Forks (coldest), Fargo/Moorhead (2nd coldest) (9/1/2004)
• Cold summer in Grand Forks (coldest), Fargo/Moorhead (7th coldest) (9/1/2004)
• Update on Cold August and Summer in Central and Southern Minnesota from NWS Chanhassen (Updated Daily)
• Cold Low Temperatures on August 19-21 from Minnesota State Climatology Office
• Minnesota State Climatology Office statement on cold August 9-11 (8/11/2004)
• All Time Cold High Temperature at International Falls from NWS Duluth (8/11/2004)

    August 2004 Statistics

Summer (June 1-August 31) 2004 Statistics