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000
FXUS63 KBIS 190540
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1240 AM CDT Sat Aug 19 2017

.UPDATE...
Issued at 1238 AM CDT Sat Aug 19 2017

With generally clear skies there is not much to change at this
time but did add some smoke to the forecast Saturday southwest and
south central based primarily on the HRRR smoke forecast.

UPDATE Issued at 1017 PM CDT Fri Aug 18 2017

The forecast for the remainder of the night remains on track.

UPDATE Issued at 633 PM CDT Fri Aug 18 2017

Little change with this forecast update other than for observed
trends through 23 UTC under smokey skies from western US and
Canadian wildfires.

&&

.SHORT TERM...(This evening through Saturday)
Issued at 353 PM CDT Fri Aug 18 2017

Fire weather concerns on Saturday are the main focus in the short
term. See the fire weather discussion below for details.

High pressure was over the Dakotas with a light northwest surface
winds. Look for mainly clear skies tonight with lows in the mid to
upper 50s.

On Saturday, an upper level ridge over the Rockies Friday night will
build eastward into the Dakotas Saturday morning, then shift to the
Red River Valley in the afternoon. Warming with southerly winds
Saturday...and went with max temps a bit higher than model blend
guidance. As the upper ridge moves east, a surface cold front will
move southeast across the state...entering northwestern ND late
Saturday morning and reaching the James River Valley Saturday
evening. South to southwest winds ahead of the front at 10 to 15 mph
will become northwest at 20 mph with gusts to 30 mph. Mixing along
and behind the front will keep temperatures in the upper 80s to mid
90s for a few hours in the afternoon.

.LONG TERM...(Saturday night through Friday)
Issued at 353 PM CDT Fri Aug 18 2017

The extended period begins with a more zonal flow aloft following
the passage of the cold front Saturday...cooling the region back
into the 70s and lower 80s Sunday through Tuesday.

The next chance for showers and thunderstorms will be Sunday and
Sunday night. The better instability lies to our south across much
of South Dakota, but southern ND may see some strong to possibly
severe storms Sunday late afternoon and evening.

Broad ridging then develops aloft over the Rockies by early to
middle of next week suppressing convection and returning warmer, but
near normal temperatures to the region.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1238 AM CDT Sat Aug 19 2017

A dry cold frontal passage will occur this period. The frontal
passage occurs in the western areodromes KISN/KDIK around 18z
Saturday, by 00Z Sunday at KMOT/KBIS, and at KJMS by around 05z.
Expect winds shifting from southwest to northwest between 15kt and
25kt. Patchy to areas of smoke possible at KDIK/KBIS, however at
this time still expecting Vfr cigs/vsbys.

&&

.FIRE WEATHER...
Issued at 353 PM CDT Fri Aug 18 2017

Will continue the Fire Weather Watch valid for Saturday that was
issued early this Friday morning.

A cold front will move southeast across western and central ND
Saturday, passing through the northwest corner late in the morning,
then sweeping southeast across central and southwestern ND in the
afternoon before reaching the James Valley Saturday evening. South
to southwest winds ahead of the front will switch to the northwest
at 20 mph gusting to 30 mph at times.

Looking at temperatures reaching the upper 80s northwest to low/mid
90s. Good mixing should occur with the cold front, with relative
humidity values lowering to around 15 percent in the southwest to
around 20 percent in the far northwest.

Contacted FMOs from southwest and northwestern ND. McKenzie/Williams
counties have had beneficial rains lately which produced some
greenup in the grasslands. However, farther south in Billings/Golden
Valley counties are likely much drier. Stark county and south may
have had enough beneficial rains...but will see what the Fire Danger
map reveals. Northwestern ND has likely had enough recent rainfall
to have some greenup occur - even in the Crosby area.

Thus the final decision for a red flag will be made after the Fire
Danger Map is available. As of now, Golden Valley/Billings counties
and south...with Stark County and south...are the more favored areas
for a red flag warning.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from noon CDT /11 AM MDT/ today through this
evening for NDZ017-018-031>033-040-041-043-044.

&&

$$

UPDATE...WAA
SHORT TERM...JV
LONG TERM...JV
AVIATION...KS
FIRE WEATHER...JV