Weather Headlines
Friday October 19 , 2001
***  Zonal flow keeps the short term quiet. Major jet stream amplification
expected in the medium range with arctic outbreak possible.***
     A weak cold front is crossing the Midwest today, but with very little
change in sensible weather. The only significant storminess over the next
several days would be a heavy rain threat over the Southern half of Florida
and a moderate rain threat in the Pacific NW. When I last wrote on Monday,
I discussed the potential for a trough to form in the Western U.S. It
clearly has not happened though I mentioned that a zonal flow would also
accomplish the forecasted warm up. This milder air should stay in place
into the middle of next week. The Western Atlantic ridge has also
strengthened in recent days which should force Gulf and East coast
temperatures to go above normal by early next week after a couple of more
coolish days. There are no named storms in the tropics at this time. A
couple of flare-ups in the Caribbean bear watching, but likely would not
develop until Monday at the earliest, if then.
Weather patterns in the 6-10 day range should become much more interesting
and bullish. All of the models forecast a strong dip of the polar jet to
occur into the Plains late next week. There are some discrepancies in the
intensity and how fast it moves East. However, given some very strong winds
in the Pacific and some very cold air now over the Arctic, I expect this to
be significant. Persistence also should pay off in this forecast. These
troughs have not had any problem digging into the Eastern U.S. since Labor
Day while troughs into the West have been non-existence. This could be
giving us clues on how the winter will go. The good news is that will aid
in verifying my winter outlook, the bad news is it could result in a long
season in the East. Specifics can wait until next week as the event gets
closer. A couple of highlights though would likely be accumulating snows in
the Northern U.S. and double digit below normal temperatures invading the
Plains and spreading East. As is usually the case, a strong trough in the
East results in significant ridging(with warmer, drier air) in the Western
U.S.
For the period October 19 through October 23, expect the following
temperature trends:
Average 1 to 3 degrees below normal: Gulf Coast, Ohio Valley, Northeast,
Mid-Atlantic, Southeast, Northern Rockies, Pacific NW...
Average 1 to 3-degrees above normal: Plains, Mississippi Valley,
California,  Central Rockies...
Average 4 to 6-degrees above normal: Desert SW, Intermountain West,
Southern Rockies...
Unspecified areas will average close to normal...