ALEXIS, ACTIVATE CRUISE CONTROL PLEASE...
As much as I love snow I do not like the bitter wind chills we usually see in our winters. So far so good for Midwesterners this year as wind and true Arctic air have not combined to make life miserable, at least not yet. I Came across this graphic from the Iowa Mesonet that I found interesting showing the wind chills we've seen so far this year compared to what's normal in Cedar Rapids and the Quad Cities. On the right in black you can see a wind chill value. Next to it in blue you can see what average is for WC (in hours) and next to that in red you can see what this year has produced to date.
The glaring trend is that we've not come close to the average hours of expected low wind chills, especially those below 25 degrees. The coldest wind chill in Cedar Rapids so far this season is 8 below where a typical period would have experienced a reading of 26 below by now. The Quad Cities has not seen a wind chill lower that 8 above compared to a typical low level of 12 below. Now that is something to be thankful for!
Bitter wind chills are certainly not in our future anytime soon as models continue to advertise a pattern that limits cold and precipitation for the next 10 days. This is the 500mb flow the EURO projects December 9th. The source region for our air is the Pacific as opposed to Canada or the Arctic. Air masses that originate there are always going to be warmer than those that descend from Canada. The warming is further enhanced when the Pacific air is forced over the Rockies and resultant downsloping moderates the air even more and destroys its ability to contain moisture.
It's not just the Midwest that's impacted by the dry westerly flow. You can see how little moisture there is nationwide with water vapor minimal from coast to coast. Florida is about the only place where PWATs are significant.
Next Tuesday (5 days from now) little has changed with available water vapor around 1/4 inch. That won't get it done as far as meaningful precipitation is concerned.
To prove my point, the GFS has no measurable rain or snow out 10 days.
The EURO goes 9 days before it finally shows some precipitation approaching.
Towards mid December the pattern does show signs of change as the mean trough in the east retrogrades into the center of the U.S. At that time we should see a more active pattern and some colder air is also anticipated, at least for a short period of time. Until then, here's what the NWS in Chicago tweets regarding temperatures in the 6-10 day period. No doubt about it, some good weather is ahead of us. The question is, will we pay for it? We usually do at some point and that will be a focus for me going forward.
WHITE CHRISTMAS WATCH
With Christmas just over 3 weeks away I'm continuing a feature called white Christmas Watch. I will try to put the ensembles of the EURO, GFS, and CANADIAN GEM up on a regular basis to give you an idea of what the models are showing for snow potential approaching Christmas. I do want to stress these are absolutely NOT forecasts and are not intended to be taken as such. Ensembles are an average of numerous solutions, some with more snow and often others with none at all. However, the average gives forecasters an idea of where trends are heading. When all three models are showing 6 or more inches in a given area that is a strong trend and one that probably has merit. 1-2" is low end and nothing to bank on. Just wanted you to see what I see behind the scenes and thought you might find it fun to watch as arm chair quarterbacks. There's a multitude of other factors that must be considered. Alright then, here you go with output that extends out to roughly Dec. 18-19th.
The EURO ensembles (51 member solutions)
The GFS ensembles
The Canadian (GEM) ensembles
Well, that's the latest and greatest for now. Have a fantastic weekend and roll weather...TS
21 DAYS UNTIL CHRISTMAS, WHAT ARE YOU WAITING FOR?
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