HOUGHTON - Despite being fairly far north, July is usually a pretty warm month in the Upper Peninsula. This year, however, is an exception.
Steve Fleegel, meteorologist with the National Weather Service in Negaunee Township, said this July set a record for cool daytime temperatures in the western U.P. and much of the Midwest.
"Our July is going to go down as the second coldest July on record," he said.
Daily Mining Gazette/Kurt Hauglie
A stalled lower-than-normal jet stream pattern is causing cooler-than-normal summer temperatures in the Midwest section of the United States, which are keeping beaches relatively empty, including the beach at the Raymond C. Kestner Waterfront Park in Houghton.
The record for the coldest July was in 1992, Fleegel said, and the third coldest was in 1924.
Fleegel said the average daytime high for July at Houghton County Memorial Airport is 65 degrees, but this July the average high was 59.7 degrees.
Since June 1, Fleegel said at HCMA the coldest daytime high temperature was 47 degrees on June 8. On June 1, 9 and 30, the high was 53 degrees. Also since June 1, the warmest daytime high was 90 degrees on May 20. June 23 and July 9 had highs of 81 degrees.
Fleegel said the cooler summer is being felt in much of the Midwest, while at the same time, the Pacific Northwest is experiencing record highs.
"It's largely due to the upper air pattern," he said.
The movement of higher elevation air called the jet stream is farther north than usual for this time of year in the Northwest, which allows warmer air from the south to move into the area, Fleegel said. At the same time, the section of jet stream which travels over the midwest is farther south than normal, allowing colder air from Canada to come into the area.
Fleegel said the jet stream has been stalled in its current location with a few intermittent "wiggles" north and south since early June, and although it does historically stall occasionally, it's not common for it to stay put for such a length of time.
"We might see something like that for a day or two," he said.
The last relatively cool July was in 2002, Fleegel said, but temperatures eventually warmed up in late August and early September.
"We saw a rebound to normal," he said. "Eventually, everything tries to even itself out."
As for this August, Fleegel said he expects no significant warming for the first week, with highs in the 60s and 70s. The normal average high temperatures for August are in the mid-70s.
Precipitation has been spotty in the Copper Country this spring and summer, also, Fleegel said. As measured at HCMA, precipitation for May was 2 inches below normal, June was three quarters of an inch above normal, and July was an inch and a half below normal.
Fleegel said an El Nino effect is expected out west this autumn, and that could have an effect on temperatures and precipitation over much of the country, including the U.P.
"Those tend to have us be a little above normal (in temperatures)," he said.
The El Nino effect originates in the southern Pacific Ocean and causes surface water temperatures to be above normal, which in turn affects weather over much of the planet.
Although temperatures may be above normal this autumn, Fleegel said it's uncertain how precipitation will be affected, because that depends on the temperature of Lake Superior.
"With Lake Superior there, that can make all the difference," he said.
Kurt Hauglie can be reached at khauglie@ mininggazette.com.