667 
FXUS63 KBIS 081925
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
225 PM CDT Fri Oct 8 2021

.SHORT TERM...(This evening through Sunday) 
Issued at 130 PM CDT Fri Oct 8 2021

Presently, isolated showers are occurring over portions of
southwestern North Dakota. Generally speaking, CAMs indicate these
showers should dissipate over the next few hours. Either way, 
even if they persist, minimal precipitation is expected through 
midnight. Smokey skies persist across the majority of the forecast
area through the day today, although conditions should improve as
a strong upper level low moves into the Dakotas tonight through 
Saturday. 

The aforementioned upper level low will bring widespread moderate
to heavy rain with a few rumbles of thunder possible late tonight
through Saturday night and lingering into Sunday. Enhanced
rain chances begin in southwestern North Dakota after midnight and
increase to the northeast through the remainder of the overnight
hours and through the day Saturday. Surface low pressure will 
track across South Dakota resulting in a warm frontal boundary
splayed west to east along/near the North/South dakota border. A 
few strong thunderstorms are possible in south central North 
Dakota Saturday ahead of the warm front as a low CAPE, strong 
shear environment develops. Overall, widespread severe weather is 
not expected, although it's possible a few storms could become 
severe.

Typically speaking, most of the forecast area could see an inch 
or two of precipitation with some localized areas potentially 
receiving higher amounts. Especially in areas where stronger 
thunderstorms could develop. Localized ponding of water is 
possible. However, given drought conditions and a lack of good 
soil moisture, as well as the progressive nature of any strong
thunderstorms, rain should absorb relatively quickly into the 
ground.

One major question in regards to precipitation totals comes from
the location of the dry slot. Models vary a little bit on the
exact track of the surface low, although generally keep the center 
in South Dakota as previously mentioned. That said, the majority 
of CAMs show the dry slot punching into North Dakota, especially 
in the southwestern and south central part of the state. Thus it 
is possible some locations could underperform a bit in regards to 
precipitation totals. 

.LONG TERM...(Sunday night through Friday) 
Issued at 130 PM CDT Fri Oct 8 2021

The extended period starts out with the previous upper low moving
off to the east and cold air advecting into the region. This will
start out a period dominated by below average temperatures. Many 
locations could see their first freeze of the year by the weekend 
with some potentially seeing a hard freeze. The biggest highlight
of the extended, however, is a potent Colorado low that develops 
and pushes through the region in the middle of the week. 

Models are becoming very consistent that it will develop and it
will track somewhere through the region. However, while 
confidence on the exact track of this system is starting to 
improve, it still remains relatively low at this point in regards
to effects on any exact location. Nevertheless, it definitely has
the potential to produce additional significant precipitation for
at least some, and perhaps more likely, most of the forecast 
area. Presently, models indicate the system stays warm enough that
little to no snow is expected. Still, will have to maintain an 
eye on that aspect as well. 


&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1226 PM CDT Fri Oct 8 2021

Areas of thick smoke are leading to MVFR and even IFR visibility 
across most of western and central North Dakota. Most readings are
between 3 and 5 SM, although KMOT has been 2 SM over the past few
hours. Smoke should clear out of the area tonight as widespread 
rain chances enter the region. However, that itself will create 
IFR/MVFR ceilings and visibility as well at times. Occasional 
rumbles of thunder late tonight are not out of the question at 
most TAF sites and chances for thunder increase through the day 
Saturday.


&&

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

$$

SHORT TERM...Telken
LONG TERM...Telken
AVIATION...Telken