July Review: Dry and Warm Overall

Drought unfortunately not only continued but deepened over the course of the month for many across central South Dakota. While some locations in this area received one or more thunderstorm-induced bouts of heavy rain during the second half of the month, others unfortunately missed out. For instance thunderstorms on the 29th produced 1.6” of rain 2 miles south of Fort Pierre, but the Pierre airport picked up a mere 0.03”. Also, on the 30^th, 1.93” of rain fell 3 miles west Sisseton while the airport received 0.01”. At the end of the month, Pierre had recorded just 0.17” of rainfall… the second driest July on record (surpassed only by the July of 1936 when 0.10” of rain fell). Sisseton received only 0.69” of rain: 5^th driest on record. July featured several rounds of severe weather as well, including microbursts (http://www.weather.gov/abr/20170705_Microburst_Hail) , 3” hail (http://www.weather.gov/abr/20170711_WatertownHail) and a 100 mph straight-line wind gust (http://www.spc.noaa.gov/climo/reports/170719_rpts.html).

Temperatures reached record heights as a ridge of high pressure largely dominated the region from the 1^st through the 17^th. Temperatures ended above average overall across the area for the month, and several records were reached as well. While not a record for the day, Aberdeen’s 104 degree reading on the 17^th was the warmest temperature since July 30^th, 2006 and was their 5^th 100+ degree day this year. Sisseton’s 101 degree reading on the 17^th was similarly the warmest temperature since July 30^th, 2006. Meanwhile, Pierre has reached 100 degrees 6 times this year, and Mobridge 7. The hottest temperature for July in our region was 109 degrees at Gann Valley on July 10th.

*JULY 2017*
Temperature Data	Aberdeen	Sisseton	Wheaton	Watertown
Warmest Temperature / Date	104 / 17^th	101 / 17^th	98 / 17^th	94 / 17^th
Coldest Temperature / Date	46 / 1^st	47 / 14^th	52 / 14^th	49 / 1^st, 14^th
Average High / Departure from Normal	88.3 / +4.8	86.5 / +3.6	82.4 / -0.1	83.8 / +1.2
Average Low / Departure from Normal	59.5 / +0.5	59.3 / -0.2	61.4 / +0.7	60.2 / +0.6
Monthly Average / Departure from Normal	73.9 / +2.6	72.9 / +1.7	71.9 / +0.3	72.0 / +0.9
Precipitation Data
Monthly Precipitation / Departure from Normal	2.05 / -0.97	0.69 / -2.89	0.98 / -2.22	3.21 / +0.19
Most Precipitation in 24 hours / Date	0.79 / 18^th	0.30 / 19^th	0.56 / 22^nd	1.59 / 11^th

Temperature Data	Pierre	Kennebec	Mobridge	Timber Lake
Warmest Temperature / Date	106 / 9^th	107 / 9^th	106 / 9^th	101 / 3^rd, 4^th
Coldest Temperature / Date	49 / 1^st	43 / 1^st	51 / 1^st	54 / 14^th
Average High / Departure from Normal	94.1 / +5.3	97.4 / +7.7	92.2 / +6.4	92.5 / +6.5
Average Low / Departure from Normal	63.5 / +1.6	63.9 / +1.9	62.8 / +3.3	61.3 / +1.6
Monthly Average / Departure from Normal	78.8 / +3.4	80.6 / +4.7	77.5 / +4.9	76.9 / +4.1
Precipitation Data
Monthly Precipitation / Departure from Normal	0.17 / -2.44	2.79 / +0.30	2.97 / +0.27	1.16 / -1.46
Most Precipitation in 24 hours / Date	0.04 / 5^th	1.50 / 26^th	1.18 / 19^th	0.39 / 18^th

Animation of the U.S. Drought Monitor over the month of July. For those who are experiencing drought conditions/impacts and would like to submit a report on such, please visit http://droughtreporter.unl.edu/submitreport/

This photo, from Haakon county on July 26 just south of the Cheyenne River on State Highway 63, highlights how much of an impact such abnormally dry conditions have had on pastureland.

The following images are courtesy of the Midwestern Regional Climate Center and summarize July's precipitation and temperature in terms of observed values and departures from normal.