000
FXUS63 KBIS 270253
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
953 PM CDT Fri May 26 2017

.UPDATE...
Issued at 945 PM CDT Fri May 26 2017

Only minor changes to the late evening forecast. Updated current
sensible weather elements and interpolated to late evening values.

Isolated shower activity over portions of eastern Montana
continues to dissipate as we lose daytime heating and activity
moves into more stable air. Will keep the remainder of the evening
dry. After midnight a couple models bring some very light showers
into the northwest. Already had some patchy slight chance pops in
the forecast and will leave that be. Do not expect any measurable
precip. Utilized a blend of the short term models for pops
Saturday morning, bringing some slight chance to chance pops into
the northwest and north central mid to late morning. Left previous
pops in through the afternoon, which right now is a broad brush of
slight chance to chance pops dropping south and east through the
forecast area. Think the overnight shift will have a better chance
of pinpointing timing and placement after the 00Z and 06Z model
runs arrive. Limited the mention of thunder to afternoon. Updated
text products will be sent shortly.

UPDATE Issued at 531 PM CDT Fri May 26 2017

Scattered showers continue to move southeast across southern
Saskatchewan and north central into northeast Montana. Could see
a few showers track across the border into northwest and far north
central ND this evening. The threat of thunder looks to be
minimal with a dry and warm layer situated around 600MB. Thus will
keep just the mention of showers. Adjusted winds a little higher
late this afternoon and made some minor adjustments to sky cover
based on latest satellite trends. Otherwise no significant changes
other than updating latest sensible weather elements and
interpolating to mid evening values.

&&

.SHORT TERM...(This evening through Saturday)
Issued at 220 PM CDT Fri May 26 2017

Breezy conditions highlight the short term forecast.

Saturday will be a near copy of Friday across western and central
North Dakota under cyclonic northwest flow aloft. As supported by
the recent observed trend, did favor the higher edge of forecast
guidance for wind with northwesterly gusts of 25-35 kts for most
areas. Diurnal scattered showers and isolated thunderstorms are
possible Saturday ahead of a vort max embedded in northwest flow
that will propagate southeast out of Canada during the afternoon.
Given inverted V-soundings and environmental momentum, a few
storms could have gusty winds over 40 mph.

.LONG TERM...(Saturday night through Friday)
Issued at 220 PM CDT Fri May 26 2017

A windy Sunday followed by dry and quiet weather into next week
highlight the extended forecast.

Once again, trended towards the higher edge of the 12 UTC guidance
suite for winds on Sunday under cyclonic northwest flow aloft.
Winds are expected to be stronger on Sunday with gusts between
30-40kts possible. There is a chance of rain showers and perhaps a
thunderstorm from the Turtle Mountains through the James River
Valley on Sunday in association with the impacts from another
impulse embedded in northwest flow aloft. Cyclonic northwest flow
aloft is favored by the 12 UTC global models through mid next
week, suggesting a continuation of dry and near to slightly below
normal temperatures.

&&

.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 945 PM CDT Fri May 26 2017

VFR conditions are expected through the forecast period. Gusty
northwest wind early this evening will diminish to around 10 mph
but will pick up again on Saturday late morning and afternoon.
Cumulus and stratocumulus deck will dissipate through the evening.
There will be an area of mid and high level clouds along the
southern tier counties with no affects to aviation. Expect another
round of cumulus development again Saturday. In addition a vort
max embedded in northwest upper flow is expected to bring an area
of showers and possible thunderstorms across the north around
17-19 UTC and spreading south and east through the afternoon. May
include a VCSH some area based on Saturday PoPs but not confident
enough at this time for a mention of Thunder at any one TAF site.

&&

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

$$

UPDATE...TWH
AVIATION...TWH