073 
FXUS63 KBIS 070017
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
617 PM CST Sun Nov 6 2016

.UPDATE...
Issued at 606 PM CST Sun Nov 6 2016

Have decided to remove shower/thunderstorm chances over the
southern James River Valley this evening. High res models have
backed off with precipitation chances, and instability has
diminished. Otherwise, remainder of forecast looks good.

&&

.SHORT TERM...(This evening through Monday)
Issued at 227 PM CST Sun Nov 6 2016

Latest water vapor imagery loop indicative of southwest flow aloft
with increasing moisture/clouds especially across central ND. A
leading shortwave was seen across northeast Montana moving into
southeast Saskatchewan this afternoon. Local radar continues to
shows some mid level returns across northern ND. Possibility of a
shower or two developing through the afternoon as another shortwave
in southwest ND moves northeast into north central ND. Will maintain
an isolated shower mention across the north central until 00Z
Monday, as is supported by the operational GFS, GFS Ensemble Mean, 
and the SREF precipitation forecasts.

A Pacific shortwave trough now working through northwest Montana
into southern Alberta will move east with time, shifting through
western and central ND during the day Monday. An associated
surface cold front will sweep through western and central ND tonight.

Lastly, a couple of weak shortwaves were seen circulating within
the southwest flow across western and central South Dakota. These
shortwaves are associated with the closed upper low that was over
the four corners the last few days and is now an open wave over
the southern plain states. Expect these shortwaves to impact the
southern James River Valley this evening.

That being said, weak instability is evident across far south
central ND per SPC Mesoscale Analysis page with most unstable cape
around 100 J/Kg, mid level lapse rates 7.5C/km, and Pwats between
0.7 and 0.9 inches. This is forecast to slide into the James River
Valley this afternoon and evening. Hi-resolution models suggest
that if precipitation does develop, then the favored area is eastern
LaMoure and Dickey counties between 00z and 06z Monday. Forcing
per Q-vector Divergence field is weak, and given the limited areal
coverage of the above mentioned instability field, will keep the
a mention of the shower/thunderstorm potential, but limit it to
the far southern James River Valley this evening.

Behind the surface cold front Monday, H85 temps fall back to between
+2C to +4c Monday afternoon. This replaces our recent warmth which
was linked to H850 temps between +14C and +16C. Thus highs Monday
will be in the 50s, which is still above normal highs for this
time of year. Area of clouds now in western Alberta will break
off in the northwest flow behind the cold front and slide into
northern ND Monday. Hence expect more clouds than sun north
Monday, with increasing sunshine farther south. In addition with
northwest winds 15 to 30 mph, it will feel a bit more crisp all
around versus previous days when we had no wind. 

.LONG TERM...(Monday night through Sunday)
Issued at 227 PM CST Sun Nov 6 2016

Another ridge rebuilds across ND Tuesday into Wednesday with H850
temperatures returning to +14C to +16C by Wednesday afternoon. Thus
we continued the trend of adjusting given gridded guidance upward
to match highs closer to what has been occurring under these
conditions. With ample sunshine both days, highs Tuesday will
reach between 55 and 65 degrees; and upper 60s to lower 70s
Wednesday. If this trend continues, record highs in Bismarck and
Williston would be reached Wednesday, with near record highs at
Dickinson and Minot.

Another cold frontal passage will occur Wednesday night with
cooler and breezy conditions Thursday. Still no threat of any
precipitation with these frontal passages. High temperatures will
return back into the 50s Thursday and Friday. Brief ridge builds
in again Friday and Saturday, but thereafter, there seems to be a
trend toward more frequent cold frontal passages, which would limit
any significant warming as we had in previous days. Earliest signs
for any measurable precipitation possibly just beyond this long
term period, that being Monday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 606 PM CST Sun Nov 6 2016

MVFR cigs possible Monday morning through mid-day over north
central North Dakota as a weak disturbance moves through.
Elsewhere...VFR conditions are expected to prevail.

&&

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

$$

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