Brief July Climate Summary

Brief July Climate Summary:

Despite a very warm conclusion to the month, most areas of the state reported a mean monthly temperature for July that was 1 to 3 degrees F cooler than normal. Although there were many days that brought 90°F maximum temperatures to various parts of the state, there were a number of nights when the minimum temperatures dipped well below normal.

According to NOAA data for the Minnesota climate station network, there were 19 daily warm maximum temperature records set or tied and 8 daily warm minimum temperature records set or tied. On the other hand, and mostly during the first half of July there were 65 cold daily minimum temperature records set or tied and 37 cold daily maximum temperature records set or tied, including an afternoon high of only 57°F at Two Harbors on July 20th. Extremes of temperature for the month ranged from 102°F at Canby (Yellow Medicine County) on the 27th to 33°F at Goodridge (Pennington County) on July 6th.

Overall, most Minnesota climate stations reported a drier than normal month. However, some highly variable strong thunderstorms helped produced widespread hail above normal rainfall in some areas, especially in far southeastern counties where some observers reported over 5 inches for the month. Conversely over 50 climate stations reported less than 1 inch of rainfall for the month, and in some cases record low rainfall, mostly in northern and southwestern counties. A sampling of those reporting a very dry month include:

Springfield (Brown County) 0.39 inches, driest July of record
Brainerd (Crow Wing County) 0.67 inches, 3rd driest July of record
Hawley (Clay County) 0.88 inches, 5th driest July of record
Park Rapids (Hubbard County) 0.73 inches, 7th driest July of record
Minneota (Lyon County) 1.58 inches, 11th driest July of record

With the somewhat spotty July thunderstorms there were just 5 daily record rainfall amounts reported during the month within the state climate network. Those included a record 2.81 inch rainfall at Jordan (Scott County) on July 26th.

Though drought in Minnesota held somewhat steady over the past week, the drought picture across the state worsened during the month of July. The drought outlook released earlier this week by the NOAA Climate Prediction Center shows that drought will persist across the state through the end of August. The good news is that climate models suggest the drought situation across the southern half of the state should improve during September and October.

By month’s end 49 percent of the state corn crop and 49 percent of the state soybean crop were in poor to fair condition, with 60-70 percent of stored soil moisture conditions rated short or very short of normal according to the USDA.

Weekly Weather Potpourri:

The NOAA National Weather Service Forecast Office in Phoenix, Arizona published some July climate summaries for Phoenix and Yuma this week. They both recorded their hottest July in history, with Phoenix reporting daily high temperatures of 110°F or greater on every day but one. The average daily high temperature was 114.7°F for the month in Phoenix and 110.7°F in Yuma. Twelve daily high temperature records and 16 warm daily minimum temperature records were broken in Phoenix.

Speaking of hot months, the Weather Underground featured an article this week about some of the cities in the USA that recorded their hottest month in history during July. Some on this list include Baton Rouge, Las Vegas, Tucson, Albuquerque, El Paso, and in Florida places like Tampa, Miami, Ft Myers, and Key West. Caribou, Maine also recorded its hottest month.

Typhoon Khanun damaged homes and took out power on Okinawa and other parts of southern Japan earlier this week and moved over the east China Sea. But the Joint Typhoon Warning Center was expecting it to make a U-turn and head northeast to bring even more rainfall to portions of Japan again by early next week.

MPR listener question:

We recorded 20 days with 90°F or greater maximum temperatures here in the Twin Cities through July 31st and have started August with at least two more such days. On average how many more days might the temperature get that high before we get some nice autumn weather?

Answer:

Indeed, by the end of the day Friday, the count of 90°F days for the Twin Cities this year will likely be 23. On average we get 4-5 such days in August, plus another 1-2 in September. On rare occasions we have had as many as 5 or more such days in September. This year I would guess we might see 25-28 days of 90°F weather before the real autumn season sets in.

Twin Cities Almanac for August 4th:

The average MSP high temperature for this date is 82 degrees F (plus or minus 8 degrees F standard deviation), while the average low is 65 degrees F (plus or minus 6 degrees F standard deviation).

MSP Local Records for August 4th:

MSP records for this date: highest daily maximum temperature of 102 degrees F in 1947; lowest daily maximum temperature of 64 degrees F in 1952; lowest daily minimum temperature of 48 degrees F in 1978; highest daily minimum temperature of 76 degrees F in 1947; record precipitation of 2.65 inches in 1941. No snowfall on this date.

Average dew point for August 4th is 59°F; the maximum dew point on this date is 75°F in 2001; and the minimum dew point on this date is 37 degrees F in 1923.

All-time state records for August 4th:

The state record high temperature for this date is 106 degrees F at Beardsley (Big Stone County) in 1947. The state record low temperature for this date is 29 degrees F at Tower (St Louis County) in 1972. The state record precipitation for this date is 6.00 inches at St Francis (Anoka County) in 2002. No snowfall has been reported on this date.

Past Weather:

This Sunday marks the 157 Anniversary of the Wisel Flood in southeastern Minnesota. On August 6, 1866 a stationary weather front parked over southern Minnesota generated thunderstorms that produced up to 10.30 inches of rainfall in Sibley County. St Paul weather observers reported a rise of 4 feet in the Mississippi River. Many other areas of south-central and southeastern Minnesota received enormous amounts of rainfall as well. In Fillmore County tragedy struck as the Root River near present day Lanseboro rose so rapidly with the flash flooding that it swept away 30 pioneer settlers to their death. Among them were members of the Wisel family in Preble Township, thus the storm took on the name of the Wisel Flood. The town of Houston was completely submerged and the nearby railroad tracks were under 7-8 feet of water.

The warmest August 4 in state history was in 1947 when over 50 climate stations reported an afternoon high temperature of 100°F or greater. It was a very sweaty day too because of high dew points.

A cold morning greeted campers in northern Minnesota on August 4, 1972 when many climate stations reported temperatures in the 30s F. Some areas reported frost and Tower reported a morning low of just 29°F. Kelliher (Beltrami County) saw the afternoon high only climb to 62°F.

Outlook:

Cooler temperatures with chances for showers and thunderstorms over the weekend, especially in the southern half of Minnesota. Generally dry with cooler than normal temperatures across the state continuing for Monday and Tuesday. Increasing chances for showers and thunderstorms on Wednesday. It will remain cooler than normal for much of the week.