Wednesday, December 28, 2011

How will I know?
-  1986 single by Whitney Houston


9:45 PM EST 12/29/11 | Now we know... weekend Alberta Clipper takes first step in pattern development leading to a significant Eastern U.S. snow event in weeks ahead. Details by Affiliate Forecaster Matt Baranowski of Storm Central are posted in our Winter Stormcast Zone and in the Western Great Lakes page.


9:45 AM EST 12/28/11 | The latest North America snowcover map from the NOAA National Ice Center shows our current winter pattern has much work remaining before snow can be delivered to hungry Powderhounds across the country. Large High pressure systems entering the U.S. continue to take up residence in the same place in recent weeks: Where snowcover is the most extensive. This "Day 6 projection" from the Hydrometeorological Prediction Center below shows that once again, another large High is set to park deep in the heart of Texas. This High will further solidify snowcover left behind by the two recent storms, both of which were covered by our Central Plains Winter Stormcast Team in facebook.

This map for Monday, January 2 shows a near-direct "Polar flow" for much of the MidWest and into the East. North winds on east side of the High, in combination with a departing weak Low pressure in the St. Lawrence River Valley, will fuel the Lake Effect Snow engine into New Year's Day. However, for those along the East coast yearning for snow, this type of pattern is great at delivering the cold air needed, but also shoves the energy needed for a storm off the coast or out to sea. So if Whitney Houston were a Powderhound, and asking, "How will I know" when we will ever get snow...

Since you're "asking us what we know about these things,"  when it comes to Winter Weather forecasting, we're passionate about procedure before releasing a grandiose storm projection. Thus, the team has reviewed latest winter weather data and set these requirements for a big coastal storm:
  • Several Alberta clippers deliver periods of snow to the Appalachians, with trailing cold fronts;
  • This introduction of cold air and occasional snow, produces consistent snowcover in all U.S. land areas from Montana to Kansas to Ohio;
  • A full latitude trough establishes in the Eastern U.S., complemented by a strong western U.S. ridge, delivering a large High pressure to the region;
  • A parcel of this high pressure arranges in the vicinity of southern Ontario, with companion dome in the Mid-south;
  • The Sub-Tropical Jet Stream begins to amplify and over-run the southern dome of high pressure.
Simply put, it is called "Cold Air Damming." This meteorological phenomena is the most sure-fire way to get a snowstorm cranking along the Eastern U.S. A wave of Low pressure can develop along a trailing front in the Tennessee Valley, and fueled by moisture transport from the Gulf, the Low would charge into a continual supply of cold air funneled down the Appalachians. 


Once those factors begin to align, then we can start talking about something like this...the February 12-15, 2007 Snow & Ice Storm. 


Until then, keep dreaming about your walks in a winter wonderland, and soon enough your dreams will come true. 


(Forecaster Foot and the Winter Stormcast Team)



14 comments:

NeedaSnowday said...

Just read Wes Junker's CWG outlook...  deee-pressss-ing!

http://www.washingtonpost.com/blogs/capital-weather-gang/post/january-weather-outlook-warmer-than-average-below-average-snow/2011/12/28/gIQAjjLoMP_blog.html#pagebreak

"I am forecasting above average temperatures and below average snowfall, but I do think we’ll see accumulating snow."

Andy, Southern York County, PA said...

He may bust, but time will tell ;)

NeedaSnowday said...

True....

AND GUESS WHAT !!!!   ..... got a lil snow today... heavier than flurries...  melted upon cotact, but hey, it was snow! :)

NeedaSnowday said...

Saw your pics on AMWX... sweet!

Amy said...

Talk about a bummer of winter so far.  Doesn't look like it's getting any better either. Oh well... at least HoCo won't go to school through the 4th of July this year.

Andy, Southern York County, PA said...

something is better than nothing 8-)

NeedaSnowday said...

Yep... combine that with a return to schools on JAN 2 and VOILA... <insert> happy campers.. </insert>

hocoKtchr said...

Amen sistah!  Preachin to the choir!!! 

Andy, Southern York County, PA said...

<span>My half inch of snow from yesterday melted.  I have filed a formal complaint with the owners of Foot's forecast for the lack of snow</span> :( :'(

Julee said...

Andrew,

Let me know how that pans out.

HAPPY NEW YEAR FELLOW FLAKEY FOOT FOLLOWERS!

Julee

ravensbbr said...

<span>Not sure which I want to happen more, sig snowfall or a Ravens win and bye week. Ehh, it's close...OK, both! </span> :-P

Tina said...

One outta two ain't bad...

Amy said...

I can only imagine the grumpiness waiting as we wake tomorrow, in the dark, while everyone and their brother enjoys the federal holiday.  Grrrr.

hocoKtchr said...

Yeah, it was a real joy!  But... we are one day closer to June!!!   O:-)   That was my only saving grace today!!!  But, there were snow flurries at dismissal which made all of my kindergatners scream, "It's snowing!!!"  over and over again!  Too fun, and I was joining in!!!!  Bring some more snow man!