June-Tober: Summery week opens warm October

LHYC webcam shows picture perfect morning on Lake Harriet Monday.

80 degree high at MSP Sunday (80 is average for June 18th!)

+16 degrees vs. average (Average High Sunday was 64 degrees)

83 in Fargo and Grand Forks Sunday!

96 degrees in Rapid City Sunday

Thermal Ridge:

Welcome to life under the "thermal ridge." That's what meteorologists call the axis of warmest temperatures under these big ridges of high pressure called "Omega Blocks."

Omega Blocks are so named because they look like the Greek letter Omega on upper air charts. This one will be around all week.

While both coasts shiver with 40s and snow in Pennsylvania and 50s and in the Pacific Northwest, Minnesota lies under the warm summery ridge of high pressure. In fact, it was warm in the Twin Cities Sunday than New Orleans (74 degrees) and Los Angeles (76 degrees) and every bit as warm as Tampa which also topped out at 80 degrees Sunday!

Look for a string of days at or above 80 in southern and western Minnesota this week!

Warm October preview?

The first week of October will run a good 15 degrees above average for Minnesota. A weekend cool front may drop temps into the upper 60s for highs by early next week, but there are signs we may warm back into the 70s again later next week.

That should put the first two weeks of October a good 10 degrees above average or so, and that could be an "insurmountable" lead on an above average October in the Upper Midwest. Looks like CPC has the right idea with the monthly temp forecast we first showed you last week.

Warm October trends:

The jet stream has been shoved north this month. Historically, a fast moving jet stream right over Minnesota in October means rapid weather changes, with sharp cold fronts punctuated by brief warm spells.

Not this month, and not lately. My MPR colleague and UM Professor Dr. Mark Seeley has mentioned many times that data is showing warmer weather lingering into fall the past few decades in Minnesota.

Spetepmeber: Driest on record for much of Minnesota

Mark also highlights the driest September on record for Minnesota in his weekly Weather Talk blog post.

Topic: Preliminary Climate Summary for September

"Most Minnesota climate observers reported an average monthly temperature that was within 1 or 2 degrees of normal, either side (warmer or colder)-. Some were slightly cooler than normal (SE Minnesota for example), while others were slightly warmer than normal (central MN). Extreme temperatures for the month were: 94 degrees F at Madison, Canby, MSP, Redwood Falls, and Winona on September 1st; and just 19 degrees F at Embarrass, Wannaska, and International Falls on the 15th. Minnesota reported the nation's coldest temperature for the 48 contiguous states 4 times during the month: on the 15th, 16th, 17th, and 24th.

On the 28th (Wed) this week, International Falls set a new temperature record with a high of 82 degrees F, while a number of other Minnesota communities reported near-record values, including: 91 F at Milan, 85 F at Artichoke Lake, 82 F at Thief River Falls, and 80 degrees F at Grand Rapids.

September was a drier than normal month across nearly all of the state, especially western and southern counties. Many observers reported less than 1 inch of rainfall. One of the few observers reporting above normal rainfall was Grand Meadow in southeastern Minnesota where they had 4.27 inches. For many September, 2011 was one of the driest in history with less than half an inch of rainfall, and measurable rain on only 4-5 days during the month. Some of these included:

0.36" at MSP Airport (driest ever)

0.25" at Marshall (2nd driest)

0.05" at Lamberton (driest ever)

0.23" at Pipestone (2nd driest)

0.39" at Chaska (3rd driest)

0.41" at Wheaton (5th driest)

0.21" at Madison (driest ever)

0.34" at Browns Valley (3rd driest)

0.36" at Milan (4th driest)

0.39" at Gull Lake (5th driest)

Traces of snow were reported in NE Minnesota on the 14th.

Several observers reported multiple days with wind gusts over 40 mph. Wind gusts over 50 mph were observed on the 29th, including 55 mph at New Ulm, 56 mph at Rochester, and 53 mph at MSP. A steep pressure gradient was driving the wind across the region."

With rainfall now over 3" below average since August, much of Minnesota is slipping back into drought.

This is a good week to get some water on your yellowing pine & spruce trees. A slow soaking with your hose on a trickle for a couple of hours will do wonders. It's also a great week and to get those outdoor projects done!

PH