Weather SummaryWritten by Theresa Rose on June 18, 2019
Provided by Justin Glisan, Ph.D., State Climatologist, Iowa Department of Agriculture and Land Stewardship
Unseasonably cool temperatures returned to Iowa after a week of warmer than normal conditions. Drier than normal conditions also prevailed across a majority of the state with rainfall deficits between a half to an inch below normal in the western half of Iowa. Pockets of above average rainfall were found in north-central and eastern Iowa.
A weak cold front moved through on Sunday (9th) bringing cooler than normal conditions across western Iowa. Overnight lows into Monday (10th) remained cool, dipping into the low to mid 50s; northwestern Iowa reported lows in the upper 40s, six to nine degrees below average. Monday was dry and windy under mostly sunny skies. Northwest winds behind the cold front kept highs in the upper 70s, two degrees below average statewide. Tuesday (11th) saw rainy conditions across much of the state as multiple waves of showers and a few thunderstorms moved through Iowa ahead of a low pressure system. Northern and western Iowa saw the highest rainfall accumulations, with totals up to 0.20 inches above normal.
The low and attendant cold front continued to move through on Wednesday (12th) bringing measurable rain across much of Iowa. Two-day rain totals, reported at 7 a.m. on Thursday (13th), ranged from 0.10 inches in Van Meter (Dallas County) to 0.86 inches in Waukon (Allamakee County). The statewide average was 0.22 inches, 0.12 inches below average. Thursday was pleasant and mostly sunny, as a high pressure system over Missouri brought nice conditions across to the region. Highs were in the low to mid 70s in eastern Iowa and mid to upper 70s across the western half; temperatures statewide were six degrees below average.
Friday (14th) remained unseasonably cool under partly to mostly cloudy skies with rain showers moving across much of the state. Another wave of showers moved through extreme southern Iowa into the morning hours on Saturday (15th). Rain totals for the 24-hour period ending at 7 a.m. were generally under 0.10 inches with higher accumulations near the Iowa-Missouri border. Creston (Union County) reported 0.67 inches.
Saturday afternoon was active with thunderstorms firing in an unstable atmosphere, initially across northern and eastern Iowa. Many of the thunderstorms turned severe almost immediately with multiple reports of hail and straight-line winds across 12 counties. A land spout tornado also reportedly caused barn damage in Whitten (Hardin County). As the afternoon progressed, strong storms began to pop in central Iowa and eventually consolidated into a squall line that moved into eastern Iowa during the evening hours. There were pockets of moderate to heavy rainfall with totals ranging from 0.22 inches in Dakota City (Humboldt County) to 2.28 inches in Toledo (Tama County); nearly 20 stations reported measurements above one inch. The statewide average rainfall was 0.74 inches, 0.57 inches above average. Overnight lows into Sunday (16th) remained near seasonal with temperatures in the low to mid 60s.
Weekly rainfall totals ranged 0.10 inches at Allerton (Wayne County) to 2.59 inches in Garwin (Tama County). The statewide weekly average precipitation was 1.06 inches, while the normal is 1.19 inches. Temperatures averaged 65.0 degrees, 5.2 degrees below normal. The week’s high temperature of 88 degrees was observed in Ames (Story County) and Des Moines (Polk County) on the 15th, on average six degrees above normal. Estherville Municipal Airport (Emmet County) reported the week’s low temperature of 40 degrees on the 13th, 17 degrees below average.