19 July 2011
Plains Heat is Moving East, While Iowa & Minnesota Melt Under Extreme Heat
Posted by Dan Satterfield

The intense heat and humidity will spread east by Friday. Dangerously high heat indexes appear likely in VA and NC.

The latest GOES 13 imagery shows the intense heat and the ring of fire (thunderstorms) around the upper level high. NOAA img ctsy Univ. Wisc- CIMMS.
The intense upper level high responsible for the heat in the Plains will move eastward later this week, with heat indexes over 115 are very possible in the Washington, DC area. There are some signs that the heat will abate somewhat next week, especially east of the Mississippi, but the Southern Plains will continue to bake. I saw an 80+ dewpoint in North Dakota yesterday- amazing. Minneapolis tied their highest all time dewpoint at 81F (27.2C).
Tropical Storm Bret is undergoing shear, and the center is now exposed, so weakening is very likely…
From NOAA’s Hydrometeorolgical Prediction Center:
...SELECTED HIGH HEAT INDEX VALUES FROM MONDAY JUL 18 2011... ...ILLINOIS... FREEPORT 124 MOLINE 112 RANTOUL 111 ...INDIANA... GRISSOM AFB 110 LAFAYETTE 106 ...IOWA... KNOXVILLE 131 NEWTON 129 ATLANTIC 126 COUNCIL BLUFFS 126 ORANGE CITY 123 ALGONA 122 ANKENY 122 ...KANSAS... LAWRENCE 110 TOPEKA 108 ...MICHIGAN... LENAWEE COUNTY ARPT 107 ANN ARBOR 105 ...MINNESOTA... MADISON 124 HUTCHINSON 123 AUSTIN 121 REDWOOD FALLS 119 ROCHESTER 118
The unit of the Celsius or centigrade scale is degree, Celsius degree (°C), not “Celsius” (C)…
True, but I wrote that post on Windows junk which makes getting a degree symbol a pain. Point taken, but I should have used Kelvin and not had to worry about it!