Friday, July 11, 2014

NO POLAR VORTEX, A Quick Explanation and Misconseptions

Thoughts on Recent "Polar Vortex" Forecast:

Well....Polar Vortex coming next week, good joke. To clear up one of the largest misconceptions in the public weather belief, this winter we never had the polar vortex over us....just various pieces of cold air from this synoptic scale circulation that someone decided to call the whole "polar vortex" in the media somewhere! Furthermore, the polar vortex is formed by pools of cold air of which are caused by long dark nights and significant snow cover. It is then trapped near the north pole by a strong west to east jet stream....but since its summer and light 20-24 hours a day this pool of very cold air never fully develops and the snow pact sees and large dent in its depth.  Yes, early next week will bring a "similar" upper level pattern to January, but NO Polar vortex.  Anyways....if you are stuck in clouds Monday and Tuesday highs will be nearly 20 degrees below normal in most places!
Please spread the word if you hear friends chatting about the upcoming polar vortex or share on Facebook! Good night all.

Wednesday, July 9, 2014


Here is the latest 6-10 day outlook from the Climate Prediction Center, this is looking like the same weather pattern in late winter and early spring!

Some computer models have low temperatures in the upper 30s over the weekend in the far northern Great Plain, nonetheless in the lower 48!

For the Midwest....any days of complete cloudiness during the afternoon will likely keep highs 15-20 degrees below normal!

Saturday, July 5, 2014

Strong and Severe Thunderstorm Across the Midwest Sunday

An area of low pressure will pass through the Northern Great Lakes on Sunday bringing the threat for severe weather across Iowa, Wisconsin and northern Illinois.
Winds will shift into a more southerly direction on Sunday, this flow ushers in a much more humid and unstable atmosphere during the afternoon building a high CAPE values. With a cold front trigger and upper level shear the atmosphere will be primed in the yellow area and especially in the red shaded area on the map to the left.

On the right is the NAM Hi-Res Simulated Radar off the 00z model run. It shows a line of strong to severe thunderstorms developing in the Upper Mississippi River Valley during the late afternoon and passing through Wisconsin and Illinois in the evening hours. This is one solution, but this model has been fairly reliable in recent weeks.

The 18z GFS run develops the heaviest thunderstorms around 8-10pm and puts the location of the cold front from Lake Superior to Central Iowa around 10pm Sunday.  With this in mind, any storms to do form into an MCS or line should hold together into the early overnight hours as severe dynamics should still be in place, according to the GFS.

The latest model run can be found in the "Computer models" tab at the top of this screen.