Lack of tornadoes in JulyThe dominance of heat and lack of rainfall across the USA had a silver lining......fewer severe storms and the smallest number of tornadoes reported in July during the modern era with just 24 nationwide. In fact according to Dr. Harold Brooks of NOAA the USA reported fewer July tornadoes than the Canadian province of Saskatchewan which had plenty of thunderstorms and tornadoes (nearly 30). You can read more about this at the Climate Central web site.
August bringing a respite from July heat and drynessSo far August has brought more seasonable temperatures to Minnesota, and thankfully moisture for some areas, including portions of some of the 28 Minnesota counties in severe drought status. Through the first ten days Halstad, Itasca State Park, Bemidji, Gull Lake, Cass Lake, Park Rapids, Ottertail, Redwood Falls, Worthington, Albert Lea, Owatonna, and La Crescent have received over 1.50 inches. A few areas have received over 2 inches including Spring Grove, Zumbrota, Lamberton, Morris, and Wheaton. Caledonia in Houston County already reports over 3 inches. August 4-5 brought the first back to back days with below normal temperatures since late June, and August 10th brought the coldest temperatures (39 F at Crane Lake, Big Fork, and Orr) and lowest dewpoints since June 13th.
For the first time in many months the NOAA Climate Prediction Center is forecasting a persistent spell of cooler and wetter than normal weather for Minnesota during the mid-August period. This will continue to bring welcome relief to Minnesota agriculture, though it may be too late to boost corn yields. It will likely help soybeans, pasture grasses, and alfalfa fields.
Bullet points from Farmfest 2012-Severe drought prevails in 28 Minnesota counties, yet just 16 percent of the corn crop is in poor to very poor condition, and just 13 percent of soybeans, relatively small percentages when compared to the crop conditions in so many other states (IL, IA, MO, IN)
-Drought has pushed major commodity prices high (corn $8.29/bu, soybean $16.31/bu) and they may go higher yet. This may lead to higher food prices and higher costs for livestock feeding as the supply chain in these crops is suppressed by lower yield estimates.
-Congress left for recess with many pieces of legislation unsettled, including the new Farm Bill and other agricultural legislation.
-August weather is expected to bring some relief from stress in Minnesota's crops (with cooler and wetter conditions), but the same relief from the weather pattern may not prevail in other Midwestern states to the south.
-This is the 8th consecutive summer that severe drought has appeared somewhere on the Minnesota landscape (2005-2012), a persistence pattern than has not appeared since the Dust Bowl Era of the 1930s.
Weekly Weather potpourriUSDA Secretary Tom Vilsack designated Rock County, Minnesota as a drought disaster this week, eligible for special federal program assistance. This will include the contiguous counties of Murray, Pipestone, and Nobles as well.
NOAA released an updated North Atlantic Tropical Storm Seasonal Outlook this week. They raised the expected numbers of tropical storms for the current season to a range of 12-17, and expected hurricanes to 5-8. There have already been 6 named storms this season the latest being Ernesto. You can read more at their web site.
NOAA also stated that July of 2012 was the warmest month in history for the USA surpassing July of 1936. Persistence of hot temperatures was the signature climate pattern in July with little respite of the heat, except for the odd day or two. As a marker of this persistence 15 nights in the Twin Cities area never dropped below 70 degrees F during the month. NOAA also noted that 63 percent of the nation's landscape was in drought during July, and over 2 million acres had been consumed by wildfires. Find out more here.
Persistent heavy rains from a series of tropical storms brought flooding rains to portions of the Philippines this week, including the Manila area. Rivers flowed out of their banks and some dams overflowed displacing much of the population. The flooding caused at least 43 deaths.
The Brazilian Weather Service has sent representatives to the London Olympics to study how the United Kingdom Meteorological Service has monitored and forecasted weather for the Olympic Games venues. They will learn as much as they can to take home and prepare for their responsibilities of forecasting for the next Olympic Games in Rio in 2016.
Heat prevailed in the southwestern sections of the USA this week. On Wednesday, August 8th Tucson, AZ reported 108 degrees F, Las Vegas, NV 110 degrees F, Phoenix, AZ 114 degrees F, Thermal, CA 115 degrees F, Needle, CA 118 degrees F, and Death Valley, CA 127 degrees F. In many of these areas the overnight low temperature remained in the 90s F.
MPR listener questionI know that you said July was the 10th month in a row with above normal mean temperature, but the forecast shows we are in for a spell of below normal temperatures in August. When was the last time the August mean temperature was below normal?
Answer: The last time August mean temperature was below normal was in 2009, and just barely. That August 15 of the 31 days brought below normal temperatures. Of the top 10 coldest months of August in the Twin Cities climate record only two (1992 and 2004) are of recent vintage. See list below:
Coldest Mean Temperatures in August from the Twin Cities Climate Record (1871-2011)
65.0 F in 1890
65.1 F in 1903
65.5 F in 1915
65.9 F in 1992
66.1 F in 1977
66.2 F in 1967
66.3 F in 2004
66.3 F in 1904
66.5 F in 1902
66.5 F in 1885
So far through the first 9 days of the month the mean temperature is about 74 degrees F, so we would have to see considerably colder weather prevail for the balance of the month to make the top ten coldest.
Twin Cities Almanac for August 10thThe average MSP high temperature for this date is 81 degrees F (plus or minus 8 degrees F standard deviation), while the average low is 61 degrees F (plus or minus 6 degrees F standard deviation).
MSP Local Records for August 10thMSP weather records for this date include: highest daily maximum temperature of 101 degrees F in 1947; lowest daily maximum temperature of 59 degrees F in 1888 and 2004; lowest daily minimum temperature of 46 F in 1904; highest daily minimum temperature of 80 F in 1944; and record precipitation of 2.47 inches in 2010.
Average dew point for August 10th is 58 degrees F, with a maximum of 75 degrees F in 1938 and 2010 and a minimum of 37 degrees F in 1982.
All-time state records for August 10thThe state record high temperature for this date is 110 degrees F at Beardsley (Big Stone County) in 1947. The state record low temperature for this date is 27 degrees F at Duluth Experiment Station (St Louis County) in 1923. State record precipitation for this date is 7.72 inches at Mankato (Blue Earth County) in 1948; and no snowfall has been reported on this date.
Past Weather Features:Probably the hottest August 10th in Minnesota history was 1947 when 24 communities reported afternoon temperatures of 100 degrees F or higher. As far north as Detroit Lakes the mercury hit 100 degrees F. The heat wave lasted from August 8-11 with little respite. The overnight low at Beardsley on the 10th was a very uncomfortable 82 degrees F. Finally on the 12th temperatures dropped by 20 to 30 degrees F and brought relief.
The next year, August 9-10, 1948 brought intense thunderstorms to parts of central Minnesota. Buffalo, Cokato, and Le Sueur received over 4 inches of rainfall, while Faribault, Mankato, and Winsted reported over 7 inches, still a record amount today.
Intense thunderstorms brought heavy rains, high winds, and flash flooding to southwestern and south-central Minnesota on August 10, 1994. Mankato, New Ulm, Owatonna, St Peter, Worthington, and Lake Wilson reported over 4 inches of rain. Minnesota, Redwood Falls, and Windom reported over 5 inches, while Marshall and Vesta reported over 6 inches.