Lukewarm July; Cool August start; Warmer by State Fair time?


Lake Wobegon July

Like the children of Lake Wobegon, July in Minnesota wraps up today as "above average."

Our green lawns and brimful lakes and ponds reflect consistent spring rains and a July 13 deluge that dumped a month's worth of rain overnight in the west and south metro.

Our early July heat burst boosted crops in most Minnesota fields after our wet cool spring. Corn fields are now 71 inches high on average, just 4 inches shy of last summer at this time.

As July winds to a close today we begin to realize that about two-thirds of summer is now in the books. Tomorrow is August. The "back to school sales" are in full swing. Fall season previews flash by on your TV screen. Vikings preseason games start next Friday. College kids start heading back to campus in the next 3 weeks.

The good news? I always remind people this time of year that usually our best two to three months of weather during the year lie ahead. It's hard to beat August, September and October in Minnesota.

Before you keep reading ...

MPR News is made by Members. Gifts from individuals fuel the programs that you and your neighbors rely on. Donate today to power news, analysis, and community conversations for all.

So as we look to August and the last month of "summer" several pressing questions flow into the Weather Lab. How long into August will the cool weather last?  Will it warm up again before State Fair time? Will we hit 90 degrees again this summer? Any way to tell what kind of fall we can expect?

As usual with weather, there may be more questions than answers. But there are some trends. One thing we can count on. Gaining an extra pound or two at the fair.

524 fair crowd

22 days until the Minnesota State Fair begins

3 days above 90 degrees last year during the Fair

1,788,512 last year's attendance (2nd highest on record)

40 number of new food items at the Fair for 2013

July 2013: Split Personality

July offered two seasons this year: summer -- and Septober.

The month started with warm summery tones. The Twin Cities sweated through 7 days at or above the 90 degree mark this month. That's actually above the long term average of about 5 days of 90 degree heat in July.

So far this summer we've logged 9 days of 90 degree. That's not far from the long term average of 13 days at MSP but it's a far cry from the 31 days we sweated through last summer. Here's a good look at the history of 90 degree days from the Twin Cities NWS.

524 MSP_DAILY_MAX_TEMPS_90 degree days_2013_1
Image: Twin Cities NWS

If you arrived in chilly Minnesota last weekend though, you might be forgiven if you thought you missed a couple of months on the calendar. The month closed on a "Septoberesque" note, with record late July chill last weekend.

Overall we squeaked out another "above average" temperature month, just the 3rd this year. (January, June & July) Pending final numbers later today, it looks like July will finish close to +1 degree vs. average in the Twin Cities. June finished almost dead bang average at +0.1 degrees vs. average.

It seems hard to believe with the cool days, but so far overall this summer temperatures are running near to slightly above average in the Twin Cities.

Cool front today

Our next Canadian cool front slides through Minnesota today. As it does, scattered showers and a few rumbles of thunder ride along. Rain totals look spotty and generally under .25", but a couple hours of rain today are possible.

524 gc
Image: Twin Cities NWS

August Starts Cool

Our persistent "northwest flow" means the first week to 10 days of August looks decidedly cool, with a dry bias for rainfall. Temps will likely  run a good -5 to -10 degrees vs. average in early August.

524 wxs
Image: Twin Cities NWS

This trend is not lost on NOAA's CPC, which paints a bright blue bull's eye right over the Upper Midwest for the next 10 days.

524 10 day

The good news about this early September weather pattern is that it features plenty of sunshine and low humidity. Most days will be in the comfy 70s and that's good weather no matter what time of year for most Minnesotans. The coolness may peak next Thursday when highs may not climb out of the upper 60s in the metro with the potential for 50s up north.

Here's' the Euro models take on the next week.

524 euro
Image: Norwegian Met Institute

Will 80s or even 90 return for the State Fair?

I don't see a huge change in the overall weather pattern just yet. But there is hope that more frequent 80s, and even a stray 90 degree day or two will return by mid-late August...just in time for the Minnesota State Fair.

Both the Arctic Oscillation and the North Atlantic Oscillation show signs of trending to a more neutral or "positive" phase in about 2-3 weeks. When the NAO/AO go positive, Minnesota usually warms up.

524 NAO

It's too early to rule out an extended stretch of summer weather later in August or in early September just yet.

As we say in the weather biz, stay tuned!