Arctic Outbreak Forecast

Arctic Outbreak Forecast Issued: 10:30 AM Tuesday November 27, 2001=
Arctic Air Invading the Deep South Blizzard in the Northern Plains - Wi=
nter Precipitation in Texas Arctic air continues to push southward down =
the Plains states all the way into central Texas this morning. Blizzard con=
ditions continue from northern Wisconsin across much of Minnesota and the e=
astern Dakotas and eastern Nebraska this morning. Farther south, light snow=
has begun falling in north Texas and western Oklahoma. The storm center =
in southern Minnesota is forecast to move slowly eastward and weaken over t=
he next 24-48 hours, spreading heavy snow across the Great Lakes. Blizzard =
conditions from the Dakotas east through Minnesota will begin to slowly sub=
side by Wednesday as the low moves eastward. Most of the Ohio Valley will r=
emain above freezing to the south of this storm center, so all precipitatio=
n there should fall in the form of heavy rain. The second problem area is=
the deep south. Cold, Arctic air has now reached central Texas. As the col=
d air continues to funnel southward through Texas, a strong upper-level dis=
turbance will move across the state tonight and on Wednesday. This will res=
ult in the development of a low center near the upper Texas coast. A band o=
f moderate snowfall is forecast from the central Texas Hill Country to just=
west of the Dallas/Fort Worth area, eastern Oklahoma, and northwestern Ark=
ansas on Wednesday. Snowfall accumulations may reach 2-3 inches in central =
Texas and 3-6 inches in western and northwestern Arkansas on Wednesday. T=
here will be a very narrow band of mixed precipitation extending from centr=
al Arkansas southwest through the Dallas/Fort Worth Metroplex to between Wa=
co and College Station, TX on Wednesday and Wednesday night. With temperatu=
res hovering near freezing and a very warm ground, we do not expect much in=
the way of accumulations except for elevated surfaces like trees, power li=
nes, and bridges. Accumulations of ice in this narrow band may reach 1/4 in=
ch - particularly Wednesday late afternoon and evening. By Thursday morni=
ng, the low is forecast to be accelerating northward through the Tennessee =
Valley toward western Ohio. A band of heavy snow will extend from northwest=
Arkansas through central Missouri to northern Illinois and southern Wiscon=
sin west of the low center. A ccumulations of 3-6 inches can be expected. E=
ast of the low, heavy rain will spread across the southeastern U.S. northwa=
rd through the central Ohio Valley. Beyond the next 48 hours, we can see =
no evidence of any major Arctic air intrusion into the lower 48 states. Hig=
h pressure will be building across northern and central Canada through the =
first week of December and into the second week of December. We certainly w=
ould not be surprised if the next significant Arctic air intrusion were to =
occur during the third week of December. Chris Hebert =09