September Heat Wave Heads East
The unusually long, late summer heat wave that has wilted residents of the Midwest for the past two weeks has begun to shift eastwards today (Tuesday, September 10th). Cleveland, Ohio has measured its hottest day of the entire summer with a 96° reading. Yesterday, (September 9th) Des Moines tied its all-time September monthly heat record with a 101° temperature.
Temperatures reached close to 100° in a few communities from Ohio to Iowa by 4 p.m. ET Tuesday afternoon: 98° at Lima, Ohio; 96° in Detroit City and Troy, Michigan; 97° at Valparaiso, Indiana; 99° at Taylorville, Illinois; 97° at Janesville, Wisconsin; and 99° in Des Moines, Iowa. Some very warm nights as well: the low of 77° at Chicago’s O’Hare Airport on Tuesday morning was the warmest low ever recorded so late in the summer and the minimum was just 79° at Cleveland’s Lakefront Airport.Temperatures across the country at 4 p.m. ET (1900 UTC) on Tuesday, September 10th. Notice the exceptionally large area affected by 95°+ temperatures, more like a mid-July map rather than mid-September.
Map from NCAR.
The core of the heat since late August has been centered over south-central Nebraska where McCook, for instance, was the hottest place in the nation for a couple of days earlier this month when the temperature reached 106° on September 6th and 7th. Since August 24th the temperature has reached or exceeded 100° eleven times (that’s 11 out of the past 17 days). The 101° in Des Moines, Iowa on September 9th was the latest 100°+ temperature ever recorded for the city, the previous being 101° on September 7, 1939. Moderate to Severe drought conditions now prevail over most of the state.Drought monitor for the Upper Midwest as of September 3rd. Conditions are likely to have deteriorated further in Iowa following this past week’s record-breaking hot weather.
It has been very hot in the western Plains as well. Denver tied its all-time monthly record with a pair of 97° days on September 5th and 6th and broke its record for the longest stretch of consecutive days in September over 90° with seven such from September 2nd to September 8th.Denver’s record streak of seven consecutive days above 90° ended on September 8th. There have been some years when snow has fallen at this time of the year in the city.
Table from NWS-Denver office.
A cold front has swept down from Canada and will push the hot air ahead of it towards the East Coast over the next few days but not before daily record highs being set from Iowa to Ohio.
Christopher C. Burt