8/10/15: The Heat is On

The summer to this point has been slightly above average for much of the area, yet, extreme heat has been lacking.   90° plus days have been well below average to this point in the summer.

Average Temperature June 1 through August 9
Average Temperature June 1 through August 9

That may change in many locations this week as the warmest air mass of the season is expected to move into the northern plains.  A large ridge in the upper level wind flow is projected to be centered over North Dakota later this week as a trough develops over the Pacific Northwest.

ECMWF WMO Essential 500 mb Height/ Anomalies for 00Z Saturday
ECMWF WMO Essential 500 mb Height/ Anomalies for 00Z Saturday

Atmospheric conditions should allow for maximum temperatures in the 90° plus range from Wednesday through Saturday across this area with portions of western North Dakota perhaps reaching 100°.  The dry soils already in place, or turning dry with the projected lack of rainfall this week should help the temperatures reach these levels later in the week.

This surge in heat will be short-lived as cooler air is expected to arrive next week. Current timing looks to be on Saturday Night into Sunday as a cold front, with the best chance of storms this week moves through the region. Behind the front average, if not below average temperatures are projected for at least a few days.

 

Projected ECMWF WMO Essential 500 mb Height/ Anomalies for 00Z Thursday, August 20, 2015
Projected ECMWF WMO Essential 500 mb Height/ Anomalies for 00Z Thursday, August 20, 2015

With the ridge in place later this week, any precipitation that would occur would be isolated, meaning, much of the region will likely record little if any precipitation this week with evaporation far exceeding precipitation through Saturday.

Precipitation through Saturday from the GFS guidance
Precipitation through Saturday from the GFS guidance

With the heat will not come high dew points if projections are correct as the mean low level inflow from the Gulf of Mexico does not look to be pointed toward North Dakota at this time, so a fairly “dry” heat is expected.

Warm and dry.  The weather words of the week.

Daryl Ritchison