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000
FXUS63 KBIS 231354
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
854 AM CDT Wed Aug 23 2017

.UPDATE...
Issued at 853 AM CDT Wed Aug 23 2017

Have increased clouds a bit over portions of central North Dakota
as a short wave gradually approaches. Otherwise, remainder of
forecast looks good.

UPDATE Issued at 652 AM CDT Wed Aug 23 2017

No change with this update for today other than for observed
trends through 11 UTC.

&&

.SHORT TERM...(Today and tonight)
Issued at 303 AM CDT Wed Aug 23 2017

Latest suite of satellite imagery shows few/sct mid and high
clouds over central ND early this morning, which lines up well the
3hourly pressure falls/vertical motion. Upstream, water vapor
depicts a potent closed mid/upper level low circulating along the
central Saskatchewan/Manitoba border. The NAM/GFS indicate large
scale ascent and low level frontogenetical forcing aligning
strongly over southern Manitoba into eastern ND today. Large scale
ascent does weakly extend into the Turtle Mountains later this
morning, then shifts south into the far eastern James River Valley
this evening. At the surface, a weak backdoor cold front slips
into the Turtle Mountains by 21z, then sinks south into the James
River Valley between 00z and 06z Thursday. The National Blend of
Models, along with the ESRL HRRR/NAMNEST/RAP/HiRes NMM East all
suggest some light precipitation in/around the Turtle Mountains
this afternoon, then over the far southeast James River Valley
this evening. After coordinating/collaborating with Grand Forks,
we have decided to keep the given gridded solution of slight
chance/chance of showers in those areas mentioned above.
Elsewhere, expect mostly sunny and dry weather elsewhere. Other
than a high of 71F at Rolla today, highs will generally range from
the upper 70s in the James River Valley, to the 80s central and
west. Mostly clear tonight with lows in the upper 40s to mid 50s.

.LONG TERM...(Thursday through Tuesday)
Issued at 303 AM CDT Wed Aug 23 2017

Models have been fairly consistent with the large scale flow and
subsequent timing/placement of precipitation Thursday through
Saturday. A transitory mid/upper level ridge moves from eastern
Montana into central ND Thursday. This is ahead of our next mid
level shortwave trough which is forecast to impact western ND
beginning Thursday night, western and central ND Friday/Friday
night, lingering over the James River Valley Saturday. Instability
in the west Thursday night enough to warrant a mention of
thunderstorms, which shifts into central ND Friday/Friday night,
then over the James River Valley Saturday. An isolated strong to
severe thunderstorm possible, but nothing much more than that in
terms of severe potential at this time.

An upper level high builds strongly over the desert southwest this
weekend into early next week. Mid/upper level height rises occur
over ND Sunday and Monday, falling slightly Tuesday as a
shortwave and surface cold front slide through. The GFS and ECMWF
differ on the strength and location of this frontal passage.

Highs through the period generally range from the low/mid 80s west
to the upper 70s central.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 652 AM CDT Wed Aug 23 2017

Vfr cigs/vsbys will continue through this TAF period for all
terminals except late in the period at KJMS. Between 09z-15z
Thursday, trends for mvfr/ifr cigs and mvfr vsbys at KJMS are
becoming more likely as upslope flow and an increase in lower
level moisture occurs.


&&

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

$$

UPDATE...JJS
SHORT TERM...KS
LONG TERM...KS
AVIATION...KS