#943 Postby Portastorm » Sun Dec 11, 2011 10:34 am 
			
			
			
			Sunday morning thoughts from the Portastorm Weather Center prior to church:
* The operational runs of the GFS/Euro/Canadian for next weekend and beyond seem to have backed off some of the more "exciting" scenarios painted out yesterday.  But winter weather fans shouldn't be bummed as the operational runs for all models have struggled this season beyond the five-day period.  In other words, don't get too worked up over a single series change.  The 12z runs could quite possibly go back to the "colder" scenarios.
* It should also be noted that the ensembles for the GFS/Euro/Canadian all look "colder" next weekend than the operational runs.  Some of you may be wondering what the difference is.  The ensembles are a number of computer model runs (run at the same time) that slightly change factors/algorithims and, thus, see slightly different outcomes.  I’m not entirely sure how it works, but then the models pick a scenario most likely from all of the ensemble runs.  So … you may see a 0z GFS run which shows a snowstorm for Dallas, per se, which is a operational run. Yet, of the 24 options run for the 0z cycle, maybe 15 of them show rain (or nothing) for Dallas.  Sometimes it behooves weather fans to not only look at the operational run but the ensembles as well.
* That being said, I'm reading some encouraging things (encouraging if you like winter) about what lies ahead 2-3 weeks or so.  Joe Bastardi (of WeatherBell) sees a pattern change and possible dump of very cold air close to Christmas.  Larry Cosgrove sees a similar possibility and even mentions the possibility of the Polar Vortex relocating close to Hudson Bay by around Christmas.  The Polar Vortex is a major generator of winter weather and if it is close to Hudson Bay that means it could pull down some Arctic air into the Plains and lower 48.  David Tolleris of Wxrisk.com mentions the possibility of a stratospheric warming event.  These are precursors to major cold plunges of air into the lower 48.
* All in all, an active pattern continues and there definitely could be some real excitement for winter weather in Texas in the days/weeks ahead.
			
									
						
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