248 
FXUS63 KBIS 211505
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
905 AM CST Thu Nov 21 2019

.UPDATE...
Issued at 859 AM CST Thu Nov 21 2019

Surface observations show pressure rises in eastern North Dakota
as a surface high centered over the western side of the state
builds. Implications on the forecast today focus on how fast
stratus over the James River Valley retreats to the east. Flurries
under stratus cover were reported in Jamestown and will likely
continue until stratus erodes. This should occur by the early
afternoon. Otherwise expect clearing skies through much of the
west/central. 

We also adjusted surface temperature trends through the afternoon,
focusing on fresh snow covered areas in the northern counties.
These areas will see a slow warm-up today with the Turtle Mountain
area only reaching around 20.

UPDATE Issued at 622 AM CST Thu Nov 21 2019

Surface high pressure was over the border of eastern Montana and 
western North Dakota. Although the drier air associated with the 
high had helped clear some of the stratus clouds associated with the 
departing low pressure system, there was some redevelopment of low 
stratus and patchy fog. Meanwhile, stratus clouds across southern 
and eastern North Dakota continue to clear from northwest to 
southeast. Clouds should continue to dissipate and give 
way to partly to mostly sunny skies. After a cool morning with lows 
from around zero F northwest to around 20 south, afternoon highs 
should reach only into the mid and upper 20s from the Turtle 
Mountains and James Valley...to the lower 30s southwest.

Current forecast appears to be on track.

&&

.SHORT TERM...(Today and tonight)
Issued at 334 AM CST Thu Nov 21 2019

Currently, the strong low pressure system that brought snow to parts 
of North Dakota on Wednesday was centered over Iowa, with cold high 
pressure over Montana. Skies were clearing gradually near the high 
center in eastern Montana and northwestern North Dakota, with the 
large stratus shield remaining over the rest of North Dakota. Some 
patchy fog continued in the clearing areas in northeastern Montana, 
northwestern North Dakota and over part of Saskatchewan.

The cold surface high is forecast to drift east over the Dakotas 
today and slide southeast toward Iowa/Nebraska tonight. Clouds 
should decrease gradually today, but it will be a cool day with 
highs from the 20s to the mid 30s. Southerly winds will develop 
tonight as the high exits our area to the southeast, but mostly 
clear skies should allow temperatures to fall into the teens over 
much of western and central North Dakota.

.LONG TERM...(Friday through Wednesday)
Issued at 334 AM CST Thu Nov 21 2019

On Friday, as the cold surface high exits our region to the 
southeast, we will see warm advection as an upper level shortwave 
ridge builds over the Rockies and northern Plains. The surface 
pressure gradient will tighten as well, as a fast-moving upper level 
shortwave trough over southern Alberta Friday morning intensifies as 
it moves toward western ND by late Friday afternoon. We should see 
highs Friday in the 40s mainly south and west of the Missouri River. 
Farther north (where recent moderate to heavy snow fell) 
temperatures should remain in the 30s.

Friday night the shortwave clipper moves southeast across the 
Dakotas. We should see some gusty northwest winds behind the 
associated cold front.

Warm advection returns on Saturday as another shortwave ridge builds 
into the Northern Plains. The warmest day could be Sunday - just 
before we see a cooling trend begin as a large upper level 
low/trough develops over central Canada and the north central US by 
Sunday night. Some locales in the southwest and far south central 
could see 50F on Sunday with widespread 40s elsewhere.

A cooling trend is in store next week as upper level low pressure 
continues to expand across much of central North America. High 
temperatures Monday look to be mainly in the 30s...but by mid-week 
we should see highs only in the 20s, with lows in the single digits 
and teens above zero. The cyclonic flow aloft would favor some hit 
and miss chances for light snow Monday through Wednesday.

Each model run cycle the medium range model runs continue to differ 
in their solutions regarding the possibility of a more organized 
storm system developing somewhere over the US by next Thursday - the 
Thanksgiving Holiday. As always, we will continue to assess model 
run-to-run consistency for this potential storm system.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 622 AM CST Thu Nov 21 2019

High pressure across the border of eastern Montana western North 
Dakota will move southeast across the Dakotas today, moving 
southeast to Iowa later tonight. This will gradually bring 
decreasing clouds to the region today and tonight. Expect 
IFR to Low MVFR conditions most areas to become VFR after 16-18z.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...AE
SHORT TERM...JV
LONG TERM...JV
AVIATION...JV