August 2018 was near normal in terms of temperatures on a whole. Record cold was recorded however, at both Aberdeen and Sisseton on the 2^nd: 40 degrees and 42 degrees respectively. There were a number of days where thick smoke from Western U.S. and Southwestern Canadian wildfires blocked out enough sunlight to reduce daytime high temperatures by a few degrees. Smoke was thick enough even at the surface to reduce visibility, and the air smelled of it as well. Haze filled our skies on and off again throughout much of the month thanks to a favorable upper-level wind pattern and an active fire season.

Precipitation departures range from up to 2” below average and up to 3” above average. Those who entered the month dry generally remained as such, and thus the U.S. Drought Monitor changed little throughout the month. D2/Severe Drought continues to impact portions of Brown, Spink, Edmunds and Faulk counties as of the 28^th. Further west, severe weather was a reoccurring theme especially towards the end of the month. Typically, after the jet stream jogs north into Canada in July, it tracks back into the Northern Plains in August and so a “secondary severe weather season” can emerge. This season’s began on the 23^rd when Hyde county observed two tornadoes and a 3” diameter hailstone fell just northwest of Hoven (https://www.weather.gov/abr/SevereWeatherSummary8-23-18). 4” diameter hail fell in Blunt on the 26^th, and 3.5” diameter hail fell near Presho on the 27^th. Hailstones this large are fairly uncommon, as these events accounted for 3 of the 41 days that our forecast area (http://tinyurl.com/jzlnoq8) has had reports of 3” or larger diameter hail since 1950 and one of the 25 days with 4” or larger diameter hail (last occurrence on June 21^st, 2013 in Spink County). Therefore, on average, a 3” hailstone is recorded about once every other year and a 4” hailstone about once every three years.

Temperature departures during the month of August, from the Midwestern Regional Climate Center

Precipitation departures during the month of August, from the Midwestern Regional Climate Center

Precipitation totals during the month of August, from the Midwestern Regional Climate Center

U.S. Drought Monitor comparison between the beginning (right) and end (left) of August, from the University of Nebraska - Lincoln