Update 12/8/15

I'm a little preoccupied at the moment with my daughter getting married this weekend, so this post will be somewhat brief.

In the previous post I did on the 3rd (read it here) in the outlook portion, I said "starting around December 12 and persisting for a week or two, the weather pattern will get active and likely stormy across much of the western and central U.S.".  Those changes are on track and have been showing up recently on computer forecast models with numerous differences in spatial and temporal solutions.   Here in lies the problem...

There are several global long range computer forecast models.  Most are run every 6 hours with output to many weeks into the future.  The more notable are the GFS and the ECMWF (but there are others).  Many times these (and shorter range models) have numerous errors in the output (forecast elements) and as early as 12-24 hours out!  By 4 or 5 days out these solutions are completely wrong!  It is challenging to forecasters in determining what may or may not be right.

To give an example, the following two images are snowfall for a 48 hour period ending December 18th.  The first had a large area of heavy snow across Kansas.  Just 6 hours later when the same computer model processed data, the solution for the exact same time had absolutely nothing!

 

 

This is a common theme with forecast models, especially many days out.  Every 6 hours there typically is a large difference in many elements.

Over the next few days and more, you are going to see and hear of "rumors" of storms or no storms.  Many sources of weather you will see on the internet are often going to post this output, as if it is gospel truth!  For example, go to Accuweather.  Look at specific forecasts in the future.  Check back often and notice the changes for specific days.  Why is this?  Because they typically just post this computer model output.  Many others do the same (The Weather Channel for instance).

What I do is try to look for trends and find repeating patterns and then give the most likely solution.  At this point, since I've been wrapped up in personal issues, I don't have a really confident idea.  But as I stated in the December 3 post, I was and still do expect changes lending to unsettled weather.  From this weekend and for at least 2 weeks (perhaps even longer) there should be quite a few storms across the middle of the country.  Look for a turn to wetter and often colder weather.  Once I get past the wedding (and recover lol), I'll try and pin it down.  Enjoy the rest of this mild December week!