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000
FXUS63 KBIS 190535
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1235 AM CDT Sat Jun 19 2021

.UPDATE...
Issued at 1232 AM CDT Sat Jun 19 2021

No major changes needed for this update. Just blended in the
latest observations to the going forecast.

UPDATE Issued at 958 PM CDT Fri Jun 18 2021

The forecast for tonight is on track, thus no deviations from the
ongoing forecast.

UPDATE Issued at 634 PM CDT Fri Jun 18 2021

Clouds will quickly clear over the next few hours as the mid level
wave continues off to the southeast and as sfc high pressure
builds south across the region. Overall the forecast remains in
good shape for tonight.

&&

.SHORT TERM...(This evening through Saturday)
Issued at 312 PM CDT Fri Jun 18 2021

Strong northwest winds will continue through the remainder of the
afternoon behind an exiting shortwave before brief ridging and an
area of high pressure sets in. This will quickly diminish winds
later this evening as well as clear out any lingering clouds.

Cloud cover is then expected to increase tomorrow morning as a cold
front approaches the area ahead of a deepening upper level trough.
While increasing cloud cover is expected to precede the front,
shower and thunderstorm activity is expected to initiate along the
front as it moves in later in the day Saturday into Saturday
night. A few isolated showers and thunderstorms could pop up
tomorrow afternoon across the southwest ahead of the front, but
confidence in this occurring is low at this time with only slight
PoPs in the forecast prior to 00Z Sunday.

.LONG TERM...(Saturday night through Friday)
Issued at 312 PM CDT Fri Jun 18 2021

Shower and thunderstorm chances, along with cooler temperatures,
highlight the beginning of the long term period, with quiet weather
and warming temperatures to follow.

Widespread showers and thunderstorms are expected at the beginning
of the long term period along a cold front as it moves west to east
through the area. Due to a relative lack of instability and
moisture, severe weather is not currently expected; however, a
strong storm or two cannot be ruled out.

Weak instability and vorticity will remain in the atmosphere behind
the front due to the strengthening surface low to our southeast,
which will allow for wrap-around showers and isolated thunderstorms
through most of the day on Sunday. Along with lingering
precipitation behind the front, cooler air will be ushered into the
area which will lead to an unseasonably cool start to the upcoming
week. Highs on Sunday and Monday are only expected to reach the 60s
and low 70s, with lows potentially dipping into the upper 30s in a
few spots Monday morning.

Temperatures do not remain cool for long however, as the upper
trough moves off to the east and a ridge begins to build in from the
west. Highs should reach the 80s again in some locations by Tuesday,
with minimal chances for precipitation through the middle of the
work week as dry northwesterly flow takes over aloft. By the end of
the week, the upper level flow looks to become more zonal as the
ridge shifts slightly east and begins to flatten. This pattern could
allow for a few weak waves to move through, which results in highly
uncertain chances for precipitation at this time for late in the
upcoming work week.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1232 AM CDT Sat Jun 19 2021

VFR conditions are expected through the period. However, some
lower ceilings (and increasing precipitation chances) will begin
to develop towards the end of the period. Precipitation type will
mainly be rain showers, but a few thunderstorms will also be
possible. Due to the uncertainty regarding thunderstorm coverage,
elected to just stick with vicinity showers in the forecast for
now.

&&

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

$$

UPDATE...ZH
SHORT TERM...Gale
LONG TERM...Gale
AVIATION...ZH