“Light switch” Summer of 2013: Cool wet start, extreme heat now; Cooler by Labor Day?

"Weather Whiplash" 101

It's called weather whiplash. The term was coined by Climate Central's Andrew Freedman a few years back. The idea is simple. Weather patterns seem to jump from one extreme to the next. Few things in weather seem "average" anymore.

Minnesota's "Light Switch Summer of 2013" is one example. Record late season snowfall in May and a cool wet start to summer. Flip the switch and instant summer in July with 7 days above 90 degrees. Off again in late July and early August with reports of "Snowsquatch" and frost in northern Minnesota. Now, a record breaking late summer extreme heat surge as temps soar to near 100 degrees. This summer is like as a wild weather roller coaster ride on the Midway at the State Fair.

Some cite so called "Arctic Amplification" as the reason the jet stream is buckling into more frequent/severe dips and ridges.

Now a new study by Elizabeth Barnes of Colorado State University questions the role of arctic amplification in jet stream changes. Welcome to "peer reviewed science."  This is how we learn in science. Hypothesize-attempted proof-critical challenges-refined data and findings. It's a sometimes messy but remarkably effective process.

From drought, to flood, to drought again in 6 months? Welcome to the "new normal" in Minnesota weather.

97 degrees - New record high at MSP Airport Monday (reached at 2:12pm, previous record was 94 set in 1948)

Best place to cool off? Live MN DNR "FishCam" at the Minnesota State Fair

Hottest State Fair Ever?

This is already among the hottest State Fair runs on record. Here are the details from the Minnesota Climate Working Group.

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Drought Creeps Back

Our Seattle-like early summer has trended strongly warm and dry in the second half. Rainfall is running -1.2" below average at MSP Airport since June 1st. Now areas of dryness...and even moderate drought are creeping back into Minnesota. 80% of Minnesota soil is now "abnormally dry"...the precursor to drought status.  Here's the latest US Drought Monitor.

Fire Danger Too

Scant rainfall and extreme heat = a rise in fire danger. Heres' the latest from the MN DNR on dry conditions and increasing fire danger. Keep that campfire in check Labor Day Weekend.

Crops doing okay...but dryness catching up

Soggy spring soils left a good reserve for crops to draw on this year. Timely summer rains this summer have helped make a pretty good crop so far. But dryness now has 66% of Minnesota's topsoils short or very short of moisture according to this week's MN Crop Report.

Heatwave Eases Slightly This Week: More Relief by Labor Day?

We may set fewer records this week...but it's still going to be plenty warm/hot around these parts.

There is a risk for an overnight storm the next few nights in the metro...but storm coverage continues to favor central and northern Minnesota.

A weak cool front will drop dew points Wednesday into the 60s...you'll feel some relief from the high humidity.

Thursday may bring more clouds and a chance of a little rain...but the heat returns Friday and Saturday. Here's the Euro model output from Weatherspark.

Longer Range Forecast: Models Diverge

How long will the late summer heat surge last?That depends which model you ask. The Euro brings a significant cool front south by Labor Day with highs in the 60s and 70s.

NOAA's GFS model keeps the heat into the middle of next week...then cools things off into the upper 60s and 70s.

To be continued.