THURSDAY WEATHER HEADLINES

Weather Headlines
Thursday January 24, 2002
The pattern looks more springlike than winter in the short term. Models
converging on an arctic air invasion next week. I am nibbling, but not
quite biting yet.
There is no denying the recent warmth. Temperatures overnight in parts of
the East approached 40 degrees above normal. While we do have a cold front
moving in, the cooling is moderate at best and very short in duration.
Temperatures are already rebounding in the Plains and will blow East this
weekend into next week. Five day numbers will remain well above normal. I
believe the West remains in a below normal mode. The flow is wet and
alternating between zonal off the Pacific and NW out of Western Canada.
Either way it is chilly and rain could come deep into Southern California
with very heavy Intermountain Snows.
I am once again nibbling at some arctic cold in the 6-10 day period. It is
encouraging to see the models in pretty good agreement. The cold has been
in Canada all along and the trough may finally migrate into the Plains and
become deep enough. Stopping me is recent history and the fact the Canadian
and European solutions do not bring the center of high pressure across the
border. The MRF brings it well South, but I find that unlikely. I also
believe a split flow will develop in the jet stream with two distinct jets.
One will run across the Southern U.S. with the polar jet across the North.
This may help to spin up a winter storm during the period. Its my opinion
we will finally see the coldest air of the season invade the Northern
Plains with subzero cold from Nebraska northward. This may expand East to
the Great Lakes by the end of the period and to the Eastern U.S. in a
modified form after Day 10. I do not anticipate a significant arctic cold
to go into the Pacific NW at this time though they will remain below
normal. The SE ridge should hold until just after this period so much of
the Southern and Eastern U.S. will grade out above to well above normal
this period. I should also point out that overall I am considering this a
glancing blow of cold air, not an all out pattern change. My winter
forecast from October indicated a feeling on my part that one or two
significant arctic airmasses would invade. Its certainly taken awhile and
this will definitely be a factor farther North, but this appears to be one
of those airmasses. A quick attempt to quantify this: I could see readings
as low as -25 along the Canadian border (ND and MN) with subzero lows to
Omaha and Chicago. This would be the middle or latter part of next week. I
hesitate to go that cold farther South because this is still 5+ days away
and we are absent of snowcover.
For the period Thursday January 24 through Monday January 28, expect the
following temperature trends:
Average 4 to 6-degrees below normal: Intermountain West, Desert SW,
California...
Average 1 to 3- degrees below normal: Pacific NW...
Average 1 to 3-degrees above normal: Southern Plains and Rockies...
Average 4 to 9-degrees above normal: Gulf Coast, Southeast, Central Plains,
Mississippi Valley, Northern and Central Rockies...
Average 10 to 15-degrees above normal: Northern Plains, Great Lakes, Ohio
Valley, Mid-Atlantic, Northeast...
Andy Weingarten, Meteorologist APB Energy / True Quote