Summer outlook: Heat wave to wane, temps expected to be average
IRON MOUNTAIN — A week-long heat wave may taper off this weekend while a long-range forecast from the National Weather Service suggests the Upper Peninsula might see an average summer overall.
The Climate Prediction Center has a fairly neutral temperature outlook for Iron Mountain-Kingsford through the end of the season, as well as no clear indication for precipitation.
Record highs in early June are in the low- to mid-90s at Iron Mountain-Kingsford. Saturday’s unofficial high of 94 degrees would be a record for that date — June 5 — while temperatures most days since have been slightly below record levels.
The weekend forecast calls for highs in the low 80s, slipping into the 70s by early next week. Although it may stay relatively warm, the outlook suggests no more highs in the 90s in June.
The summer solstice arrives at 10:32 p.m. Central time Sunday, June 20, as the Northern Hemisphere receives sunlight at the most direct angle of the year.
La Nina, the periodic cooling of water in the central Pacific Ocean., has ended and neutral conditions are now present, NWS forecaster Brad Pugh said. That, along with other factors, leads forecasters to predict hot months ahead, but the trend is less likely for a slice of the Midwest that includes the Upper Peninsula.
For the three-month period from July through September, the CPC calls for a 36% chance of above-normal temperatures at Iron Mountain-Kingsford and a 29% chance of below normal.
“Beginning in July and through November, above-normal temperatures are favored through the entire continental U.S.,” Pugh said. For areas of the Southwest experiencing extreme drought, the CPC sees a 60% chance of above-normal temperatures this summer.
A heat dome that settled recently over the northcentral U.S. has been more severe just west of the Upper Peninsula and northern Wisconsin. Minneapolis and St. Paul, Minn., have had the earliest seven-day period of consecutive temperatures at 90 degrees or above on record, said Jessica Storm, AccuWeather meteorologist.
Dickinson and Iron counties, along with Florence County in Wisconsin, are showing abnormally dry conditions after below-normal precipitation in May.
Rainfall for the month totaled 1.69 inches, which is about 1.5 inches below average, according to observations at the Iron Mountain-Kingsford Wastewater Treatment Plant.
Local temperatures last month averaged 52.7 degrees, which was nearly 1 degree below normal. The highest temperature was 84 degrees on May 22 and the lowest was 28 degrees on both May 10 and 12.
Temperatures continued to dip below freezing late in the month, with a low of 30 on May 29.