National Weather Service Raw Text Product

Displaying AFOS PIL: AFDBIS Received: 2022-01-19 18:07 UTC


372 
FXUS63 KBIS 191807
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1207 PM CST Wed Jan 19 2022

.UPDATE...
Issued at 1158 AM CST Wed Jan 19 2022

Wind chills in the southwest have warmed above -25 F and therefore
the advisory there was allowed to expire as planned. Though there
will be some diurnal warming today in areas of the ongoing
advisory and warning, forecast wind chills don't improve above -25
F for much of the areas. Cleared sky grids of cloud cover today
with satellite imagery showing clear skies with high pressure
building in, otherwise no changes needed. 

UPDATE Issued at 936 AM CST Wed Jan 19 2022

Surface high pressure remains parked over southern Saskatchewan
and into western North Dakota. With the maintained pressure
gradient, 15 to 25 mph winds continue this morning, mostly central
and east. With observed temperatures of -10 F to -20 F at 15Z,
wind chills remain from -30 F to -45 F. Current headlines remain
in good shape, as well as the expected expiration of the southwest
advisory at 18Z. No changes needed with this update. 

UPDATE Issued at 523 AM CST Wed Jan 19 2022

Updated the near-term wind grids based off the latest observations
and guidance, otherwise no major changes with this update. Will
maintain current headlines.

&&

.SHORT TERM...(Today and tonight)
Issued at 306 AM CST Wed Jan 19 2022

Continuing breezy conditions leading to patchy blowing snow across
portions of central and eastern North Dakota will be the highlight
of the short term period.

Surface high pressure is continuing to build into the area this
morning, with pressure rises (albeit weaker than during the day
Tuesday) contributing to a strong northwesterly breeze. Both
pressure rises and the associated winds will continue to gradually
weaken through the morning before moderating a bit during the day
today and then dropping off later this evening as the center of 
the high pressure (currently located near the Alberta/Saskatchewan
border) traverses the CWA. These winds, in addition to the much
colder airmass invading the region, will contribute to frigid 
wind chills across the area both this morning and later tonight
into Thursday. 

By taking a look at current observations and accounting for the 
continued cooling trend expected prior to sunrise this morning, 
the decision was made to upgrade to a wind chill warning for 
counties north and east of the Missouri River for wind chills as 
low as -45F. Wind chill readings are expected to rise above 
warning criteria during the day today, but then fall below again 
after sunset. Winds are expected to be rather light tonight into 
Thursday, but temperatures will be much colder with high pressure
more centered over the area. 

The advisory for the far southwest is still expected to be able to
be let go later this morning, while the "new" advisory area for
counties just along the south/west side of the river may continue
through Thursday morning as originally planned.

.LONG TERM...(Thursday through Tuesday)
Issued at 306 AM CST Wed Jan 19 2022

Cold temperatures continue to begin the long term period, followed
by a potentially more active and somewhat uncertain weather
pattern through the weekend and into the beginning of next week.

A quick warming trend is expected through Friday as brief upper 
level ridging moves across the northern Plains. A shortwave 
trough is expected to move in behind this ridging, with an 
associated clipper low bringing widespread chances for light snow 
out ahead of this shortwave Thursday night into Friday.

Beyond Friday, there is inherent uncertainty with the forecast as
strong northwesterly flow sets up across the northern Plains. The
northwesterly flow will allow for occasional chances for light
snow with any embedded waves moving through, with the blend of
guidance from the NBM currently suggesting that Sunday afternoon 
into Monday will have the best chances as another clipper low 
looks to move through. However, a lot of the uncertainty lies with
the temperature forecast as the northern Plains will be in 
between mean ridging aloft off the western U.S. coast and mean 
troughing from the Great Lakes and northeastward through Ontario. 
WPC cluster analysis suggests the uncertainty is with the 
amplitude of both of these features by analyzing the 500 mb EOF 
patterns, which is the result of significant temperature spread 
in the NBM's 25th and 75th percentiles for many of the high and 
low temperature forecasts heading into next week. In general, 
colder temperatures will be favored northeast with warmer 
temperatures favored southwest, but just how warm/cold is likely 
to change as we get closer in time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1158 AM CST Wed Jan 19 2022

Northwest winds of 15-25 kts at KMOT-KBIS-KJMS through the
afternoon, which may produce some blowing snow and brief periods
of MVFR visibility. Generally VFR conditions expected this
afternoon though. High pressure builds tonight with winds becoming
light. There is a possibility of fog after 06Z, but disagreement
in short-term guidance about placement. This may need to be added
in future updates.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Chill Advisory until noon CST /11 AM MST/ Thursday for 
NDZ017>020-034-042-045.

Wind Chill Warning until noon CST Thursday for NDZ001>005-
009>013-021>023-025-035>037-046>048-050-051.

&&

$$

UPDATE...AE
SHORT TERM...Gale
LONG TERM...Gale
AVIATION...AE