Another "Heat Spike"
Who has endured more 90-degree days this year, residents of Atlanta or the Twin Cities? If you guessed MSP you are correct. We've seen 18 days at or above 90F compared with 17 at ATL. Odd. The heat usually builds gradually, but every now and then we see a sudden hot spike, a fast-forward northward surge of soul-sapping heat.
We went from a high of 72F May 13 to 98F May 14 (hottest day of the year so far). We'll go from mid-70s yesterday to mid-90s today; a 1 in 3 shot at 100F from the far south metro to the Iowa border. Heat Advisories are posted - it may feel like 100-104F by late afternoon. I'm tempted to cool off in "Hot-lanta". A few T-storms can't be ruled out, especially over central and northern counties, but it probably won't be the sustained soaking we need to put a serious dent in the drought.
And yes, Sunday's forecast was a bust. A dud. A real stinker.
A stormy swirl held together as it pushed out of the Dakotas, producing significant rain up north; just enough sprinkles to settle the dust in the metro. With most of Minnesota in moderate to severe drought it's hard to get indignant about any rain, even on a Sunday.
Good news: we cool off into the 70s, even some 60-degree highs by late week. Enjoy, because I suspect today won't be the last 90-degree day of 2013.
Beastly-Hot. Models are consistent bring a surge of desert-heat (and tropical dew points) into southern and central Minnesota later today. The only complication: morning convection. If T-storms do push across the state during the morning or midday it will delay the "hot prod", which would mean low to mid 90s, keeping us a few degrees cooler than we would be otherwise. But even if that happens dew points will be higher, so the heat index may be nearly as high (topping 100 by mid-afternoon). 4 pm NAM forecast above courtesy of Ham Weather.
Atmospheric Wild Card. Today's surge of super-heated air may set off scattered T-storms, with a chance of an MCS system, a swarm of strong to severe storms capable of frequent lightning and very heavy rain - something you'd expect to see in June, not the 9th day of September. HRRR model data shows a potential for some 1" rains close to the metro, with a few inches over the Dakotas. I hope this 3 km, 15 hour accumulated rainfall prediction pans out. Map above: Ham Weather.
Welcome Rain? 12 km. NAM guidance shows a potential for T-storms today, especially central and northern Minnesota, but storms may brush the MSP metro area. The sun should be out by afternoon as temperatures soar into the 90s. The arrival of slightly cooler air may prolong our shower and thunder (opportunity) into a portion of Tuesday. Animation sequence: NOAA and Ham Weather.
Big Swings. A few models are predicting 100-degree heat today, which may still happen IF T-storms fail to develop and the sun is out most of the day, with southwest winds at 15-25. Relief is brewing; highs in the upper 60s to near 70 from Thursday into Sunday. Keep shorts and sweatshirts in your closet until further notice. Graph: Iowa State.
Not For The Faint-Of-Heart. With a dew point surging above 70F today (especially if rain moistens the lowest few thousand feet of the atmosphere) the afternoon heat index should top 100F. Within 72 hours temperatures may be 45-50 F cooler across much of Minnesota; morning lows dipping into the 40s by late week, with a welcome drop in dew point. Graph above: weatherspark.com.
Last Hot Front? Don't Bet On It. The way our expanded summer is going I'm not sure this is our last outbreak of stuffy air. GFS guidance shows 80s returning between September 19 and September 22, with a better chance of more significant rain the last week of September.
Photo credit above: "A view of the devastation caused by the Great Galveston Hurricane of 1900. The destruction wrought by the hurricane brought forth a new focus on the study of hurricane prediction." (Library of Congress)
Photo credit above: "In this photo provided by the U.S. Forest Service, members of the Horseshoe Meadow Interagency Hotshot Crew, from Miramonte, Calif., walk near a controlled burn operation as they fight the Rim Fire near Yosemite National Park in California Sunday, Sept. 1, 2013. The massive wildfire is now 75 percent contained according to a state fire spokesman." (AP Photo/U.S. Forest Service, Mike McMillan).
Photo credit above: REUTERS/Lucy Nicholson.
Image credit: ThinkStock.
Photo credit above: "A white snowshoe hare against a brown background makes the animal easy prey." L.S. Mills Research Photo.