Weather Headlines
Thursday December 20, 2001
Important storm about to hit the West coast. By the time it exits the East
for Christmas, a moderate arctic airmass should have finally invaded much
of the Eastern two thirds of the U.S.
The air behind the storm now exiting the NE turned out to be a little
colder than expected as 20's and 30's are widespread this morning even down
to the Gulf Coast. The first real Lake Effect snows of the season are
underway in the Eastern Lakes. Sunshine farther West will modify this
airmass to near if not slightly above normal this afternoon. But, it is a
part of a stepping down in temperatures that has gradually occurred over
the last week to 10 days. That pattern should continue as Canadian highs
are lined up to our NW and I still expect each one to be progressively
colder into early January. The next storm is plowing into the West Coast
today with rain this morning well South into Central California. This
system should emerge into Colorado tomorrow with a weekend track to the NE
toward the Great Lakes then East from there. I do expect some Christmas
weekend snows in the Northern fringes of this storm, but more real estate
will see rain rather than snow. A below normal plunge of air should follow
this storm by Christmas as ridging rapidly develops in the West deepening a
trough into the East. Five day temperature numbers still reflect an above
normal bias as we see one final warm-up the next 2-3 days before the colder
air strikes late in the period.
With model consistency on my side, I am confident that this 6-10 day
forecast period will verify colder than normal for much of the East. If it
does, it will be the first period in over two months that runs cold.
Relative to normal, it may not be as significant as some of the warmer
departures have been, but it should get some attention. There are some
differences on where the heart of the cold sets up. I believe it will tend
to be more on the Plains rather than the East Coast. But all models in this
time frame have a strong ridge West/trough East signature on them. One
additional surprise could be a Southern jet stream storm. I don't see
anything particularly ominous yet, but the setup suggests something could
be in the offing.
For the period Thursday December 20 through Monday December 24, expect the
following temperature trends:
Average 1 to 3-degrees below normal: Pacific NW, California, Intermountain
West?
Average 1 to 3-degrees above normal: Desert SW, Rockies, Gulf Coast,
Southeast?
Average 4 to 6-degrees above normal: Plains, Ohio and Mississippi Valleys,
Great Lakes, Northeast, Mid-Atlantic ?
Andy Weingarten, Meteorologist APB Energy / True Quote