Meet and Greet at the State FairFor those who would like to visit about the weather I will be at the University of Minnesota CFANS Alumni Lounge in the Agriculture/Horticulture Building on the State Fairgrounds this Saturday from 4:00 to 5:00 pm. If you plan to attend the State Fair on Saturday, please drop by and say hello.
August Heat WaveAccording to the Mayo Clinic when the Heat Index reaches 91 degrees F or higher, people should take precautions to avoid heat exhaustion, especially young people, elderly people, or those suffering from certain chronic illness (COPD, MS, etc) that require medications. This is the reason the National Weather Service issues heat advisories (Heat Index values in the 90s F to 100 F) and excessive heat warnings (Heat Index Values above 100 F), with other modifiers to take into account how little overnight cooling occurs.
The longest Heat Wave of 2013 occurred this week in southern Minnesota, starting mid-afternoon on Saturday (Aug 24) with a Heat Index of 96 degrees F in the Twin Cities and continuing through Thursday evening (Aug 29). Many high temperature records were set around the state for both daytime maximum values and nighttime minimum values. MSP reported overnight low temperatures from the 25th to the 27th of 80 F, 80 F, and 79 F. The 80 F readings were only the 5th and 6th occurrences of such high minimum temperatures in the history of August back to 1872.
Reported Heat Index Values from MSP included: Sat (Aug 24) 96 F; Sun (Aug 25) 105 F; Mon (Aug 26) 106 F; Tue (Aug 27) 107 F; Wed (Aug 28) 92 F; Thursday (Aug 29) 100 F
In addition, on Tuesday August 27th the dewpoint reached a daily record tying value of 77 degrees F, also tying the mark for the highest value measured during a run of the State Fair (tied August 28, 1955 and August 27, 1990). Perhaps more importantly, the Heat Index values in the Twin Cities from 3:00 pm on Saturday (Aug 24) to 11:00 pm on Wednesday (Aug 28) rarely fell below 83 degrees F during any given hour. Thus the persistence of heat lasted well over 100 consecutive hours. This was problematic for the opening of the school year in many school districts, especially those buildings without air conditioning, and for Minnesota State Fair goers and workers who had to worry about staying hydrated in such stressful conditions.
Keeping children hydrated and attentive for school classroom and playground activities was a challenge, not just in Minnesota but in Iowa and Nebraska as well. Many schools took precautions to avoid any health risks to their students, such as giving them more breaks, shortening recess activities or athletic activities, and taking water breaks. In the end, some school districts simply cancelled school later in the week, a smart choice and somewhat analogous to school cancellations that have occurred historically for extreme cold in the winter season (when Wind Chill Index values have ranged below -35 F), a more well known health risk to school aged children. Perhaps modifying schools to make them useful even on warm days is a good idea as our climate behavior continues to change bringing more frequent and extreme warm spells.
The high of 92 degrees F on Thursday (Aug 29) marked the 6th day with daytime highs of 90 F or greater during the run of the 2013 Minnesota State Fair, surpassing the record of 5 days with 90 F or higher that occurred in 1922, 1931, 1960, and 1991. Undoubtedly the 2013 State Fair will go down as the warmest or one of the warmest in history (back to 1885). With a possibility of 90 F or higher again on Friday (Aug 30)or Saturday (Aug 31), then the new State Fair record for 90 F days may go to seven.
Preliminary August Climate SummaryAs August wraps up this Saturday, a look back reveals a highly variable month climatically. Average temperatures for August will end up ranging from 1 to 4 degrees F above normal for most observers. The month started cooler than normal through the first half of the month, with relatively low dewpoints, then above normal temperatures, record-setting in some cases took over for the rest of the month. Extremes for the month ranged from 98 degrees F at Forest Lake on the 27th to just 31 degrees F at Embarrass on the 14th. Browns Valley set a new record low on the 14th as well with a reading of 39 degrees F. Conversely, over the period from August 20-27 as many as 30 new daily maximum temperature records were set around the state, along with 67 new daily warm minimum temperatures. The above normal temperatures help crops "catch up" a bit and move more rapidly toward maturity.
Moisture wise, the month of August was generally dry, but highly variable too. With few exceptions Minnesota observers are reporting a drier than normal month of August. Driest areas were in northwestern counties, some central counties, and the far northeast (Cook County) where total monthly precipitation was less than 1 inch. Only a handful of reported monthly rainfall totals over 3 inches. Some of the higher amounts in the state included: 4.20 inches at Windom and Albert Lea, 3.77 inches at St James, and 3.71 inches at Blue Earth. Thunderstorms brought record-setting daily rainfall at 9 locations on the 5th of the month including 1.95 inches at Wells, 1.62 inches at Winnebago, and 1.42 inches at Milan. Again on the 11th a strong thunderstorm brought a record 2.11 inches to Windom.
The drier than normal August follows a drier than normal July which has produced a combined rainfall deficiency for the two months that ranges from 5 to 7 inches below normal in many areas. The consequence of this is a re-emergence of moderate drought in over half of the state's landscape. You can read more about this at our web site.
There were three noteworthy weather features in August. On the 6th a supercell thunderstorm brought high winds and large hail to many areas south of the I94 corridor. Many communities reported hail from 1.5 to 2.0 inches in diameter, with some crop damage. Three inch diameter hail was reported in parts of Kandiyohi County. In addition winds up to 60 mph damaged trees in Dakota, Wilkin, and Hennepin Counties.
About 8:15 pm on Tuesday, August 27 a tornado, the 7th of the season for Minnesota, touched down briefly northwest of Wadena, MN near the intersection of highways 10 and 75. No serious damage was reported. And finally on Thursday, August 29th, strong thunderstorms brought hail and damaging winds to portions of northeastern Minnesota, including a measured wind of 68 mph near Castle Danger along the north shore of Lake Superior. Further the 8th Minnesota tornado of 2013 was spotted between Remer and Hill City, fortunately with little damage associated.
Climate Change Adaptation Conference at the Science Museum on November 7, 2013Several organizations are partnering to host the first statewide conference on Climate Change Adaptation, Planning and Practice. It will take place at the Science Museum of Minnesota in downtown St Paul on November 7, 2013. Registration for the all day program is only $50. Sessions will be devoted to city planning, agriculture, transportation, natural resources (including watershed management), and public health.
Weekly Weather potpourriThe RIM fire around Yosemite Valley in California has burned for nearly two weeks, charring more than 200,000 acres and costing nearly $40 million to fight (ranking among California's worst fires historically). Smoke from the fire made the air quality around Lake Tahoe very poor for many days. Though Mother Nature has not brought rain to help contain the fire, cooler temperatures are expected over the Labor Day weekend which will assist firefighters in making better progress in cutting fire breaks.
In the Western Pacific Ocean Tropical Storm Kong-Rey was expected to bring heavy rains to Japan over the weekend, and in the Eastern Pacific Ocean Tropical Storm Juliette was dissipating, though bringing the threat of rain to portions of Baja California as well.
Comments from the Brad Rippey of the USDA-Office of the Chief Economist during the drought briefing this week include:
Highlights for the drought-monitoring period ending 7 am EDT on August 27 include:
-Overall U.S. moderate to exceptional (D1 to D4) drought coverage increased more than four percentage points (up 4.43 points) to 50.04%. It was the first time that drought covered more than half of the contiguous U.S. since April 9, 2013. Hot, dry weather in the western Corn Belt led to sharp increases in drought coverage. According to the U.S. Drought Monitor, drought coverage in the nine-state Midwestern region increased from 8 to 25% during the week ending August 27. Coverage increased from 35 to 60% in Iowa; 10 to 55% in Minnesota; 15 to 31% in Missouri; 2 to 21% in Wisconsin; and 0 to 21% in Illinois. The portion of the U.S. corn production area in drought surged from 25 to 45% during the week ending August 27. Soybeans in drought also increased sharply in the last week, from 16 to 38%. Corn and soybeans in drought bottomed out last month at 17 and 8%, respectively.
MPR listener questionWith the late August run of 90 F days in the Twin Cities I wondered how common it is to have more such days in August than any other month of the year? Also, how frequently does August bring zero 90 F days?
Answer: Over the Twin Cities climate record since 1872 (142 years), there have been only 25 years (18 percent) when the month of August brought the most 90 F days. This year August and July are tied with each bringing 7 days of at least 90 F high temperatures. Coincidentally there have been only 25 years (18 percent) when August brought zero 90 F days as well, the most recent was 2011.
Twin Cities Almanac for August 30thThe average MSP high temperature for this date is 77 degrees F (plus or minus 8 degrees F standard deviation), while the average low is 58 degrees F (plus or minus 6 degrees F standard deviation).
MSP Local Records for August 30thMSP weather records for this date include: highest daily maximum temperature of 96 degrees F in 1941; lowest daily maximum temperature of 60 degrees F in 1965; lowest daily minimum temperature is 45 degrees F in 1935 and 1974; highest daily minimum temperature of 77 F in 2010; and record precipitation of 7.28 inches in 1977; No snow has been recorded on this date.
Average dew point for August 30th is 58 degrees F, with a maximum of 75 degrees F in 1951 and a minimum of 34 degrees F in 1931.
All-time state records for August 30thThe state record high temperature for this date is 103 degrees F at Minnesota (Lyon County) in 1976. The state record low temperature for this date is 26 degrees F at Sawbill Camp (Cook County) in 1935. State record precipitation for this date is 7.28 inches at the MSP airport in 1977; and no snow has fallen on this date.
Past Weather Features:Strong thunderstorms brought flooding rains to parts of Minnesota over August 29-30, 1902. Many areas reported over 2 inches, while Lake Winnie, Pipestone, and Faribault received well over 3 inches. Farm fields in Wabasha County were flooded as over 5 inches of rain fell there.
August of 1921 ended with a heat wave across southern and western Minnesota, as over 20 communities reported temperatures from 90 to 100 degrees F. The heat wave last from August 28th to September 2nd and rapidly dried out crops. Temperatures dropped off into the 40s and 50s F by the second week of September.
Widespread and damaging frost occurred on perhaps the coldest August 30 in state history, that of 1931. Temperatures in the low 30s prevailed nearly statewide with a reading of just 33 degrees F as far south as Rochester and Zumbrota. Farmers reported frost damage to potatoes, corn, and garden vegetables, virtually ending the growing season.
On the evening of August 30, 1977 dark clouds appeared on the horizon. An intense thunderstorm began about 8:30 pm and brought 4-5 inches of rainfall to the State Fairgrounds by midnight. The maximum rainfall rate occurred between 9:00 and 10:00 pm with over 2.5 inches falling. The storm total of 7.36 inches at the MSP airport remains the 2nd greatest in Twin Cities history, surpassed only by the 10 inches that fell on July 23-24 of 1987. Hundreds of homes in the Twin Cities reported water damage. Evening events, including the Grandstand Show at the State Fair were cancelled.