National Weather Service Raw Text Product

308 
FXUS63 KFGF 030027
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
627 PM CST Wed Feb 2 2022

.UPDATE...
Issued at 622 PM CST Wed Feb 2 2022

Extreme cold conditions this evening and overnight expected with a 
1042mb arctic high pressure building into the region. Temps 
currently ranging from 7 to 15 below from east to west this hour 
with wind chills as low as 35 below. As the SFC high tracks
directly across the FA light winds and clear skies will create 
ideal radiational cooling which will allow temps to fall into the
25 to 35 below range. 

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 337 PM CST Wed Feb 2 2022

Main highlights within this evening through Thursday night revolve 
around the very cold temperatures and associated hazardous wind 
chills tonight, followed by a weak clipper late Thursday resulting 
in light snow, breezy winds, and potentially some patchy blowing or 
drifting snow.

Arctic air mass continues to keep the region entrenched in very cold 
conditions. Its sfc high is expected to center itself over the tri-
state and WC MN area by 12 Z Thursday. This should allow for optimal 
for radiational cooling within the arctic air mass. Latest ensemble 
guidance continues to carry likely (70%) chances of at least -30 F 
for many locations within the CWA, more so for locations north of
I- 94 corridor. There will be usual mesoscale influencers like 
topography, urban heat island effects, and land coverage that help
temps tip on either side of the -30 F threshold.
 
Depending where the sfc high is located by sunrise, winds are 
expected to increase out of the southerly first starting west of the 
Valley behind the departing sfc high. This will only decrease wind 
chill values even in the face of warming temps. With air 
temperatures expected to be so low, any wind at all will likely push 
apparent temps into wind chill warning criteria. Hence, the current 
warning tonight through Thursday morning is still on track. 
Eventually winds will likely become breezy out of the south along 
and west of the Valley, perhaps enough to get some patchy blowing 
snow and/or some drifting snow by Thursday afternoon.
Uncertainty lies in snowpack susceptibility in being blown around.
Latest VIIRS Snowmelt RGB reveals a ripened or crusted over snowpack 
in much of central ND extending into the Devils Lake basin and 
northeast North Dakota west of the Red River Valley.
This may be evidence of limited "blowability" by the snowpack in 
these locations, and could limit the amount of blowing snow 
impacts and/or coverage. Regardless of this evidence, should any 
blowing or drifting snow develop Thursday afternoon, some minor 
impacts to travel will be possible within northeast North Dakota 
into the Red River Valley.

A weak clipper system is progged to move through the Northern Plains 
late Thursday bringing a 30-50% chance of light snow mainly along 
and north of US Highway 2 corridor. Synoptic forcing looks to be 
generally on the weak side and a lack of mesoscale forcing increases 
confidence in snow amounts given by hires and ensemble guidance of 
less than 2 inches.

.LONG TERM...(Friday through Wednesday)
Issued at 337 PM CST Wed Feb 2 2022

The main weather impacts for this period will come from cold and 
wind chills early on, then some impacts from snow/wind on Sat. 

Less frigid temps to start on Fri but still enough wind to generate 
apparent temps in the 30 to 40 below range Fri morning. After a 
reasonably tranquil Fri attention will turn to the next clipper 
system scheduled to affect the area Fri night overnight into Sat. 
This looks (similar to recent events) to be a producer of only minor 
doses of snow. ECMWF/GEFS near nil in their prob of 24 hr snowfall 
to reach 3 inches or more. As winds increase Sat afternoon, the 
question will be as to whether the stronger winds will be coincident 
with snow that is still falling. Looks like the highest push would 
succeed most or all of the falling snow, and the more west northwest 
surface wind direction could keep impacts lower along the spine of 
the Valley. Chances for coincident snow and wind thus still look to 
be east of the Valley, over areas that generally support less wind, 
so impacts from blowing snow might not be as dire for those areas as 
well.  

Flow turns more zonal early next week, increasing temps along the 
way, but we are likely to be free of more active weather through the 
middle of next week. The mercury will be trending toward 30 by Mon, 
exceeding that value on Tue.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 622 PM CST Wed Feb 2 2022

Another night of SKC and extreme cold conditions with light 
winds as arctic high pressure slides across the region. Behind the 
high south winds will develop with Thursday afternoon winds at 10 to 
15kts.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Wind Chill Warning until noon CST Thursday for NDZ006>008-
     014>016-024-026>030-038-039-049-052>054.

MN...Wind Chill Warning until noon CST Thursday for MNZ001>009-
     013>016-022-023-027-029.

     Wind Chill Advisory until noon CST Thursday for MNZ017-024-028-
     030>032-040.

$$

UPDATE...JK
SHORT TERM...CJ
LONG TERM...WJB
AVIATION...JK