Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 272349

Area Forecast Discussion
National Weather Service Bismarck ND
649 PM CDT Sat May 27 2017

Issued at 628 PM CDT Sat May 27 2017

Classic inverted V sounding at Bismark this evening. Small fall-
rise pressure couplet with strong subsidence behind a shortwave
trough is combining with this favored environment for strong
winds with convection, to produce gusty winds as high as 60 mph
this afternoon across central ND. These conditions will continue
through early evening from south central ND into the James River
Valley. Thunderstorms have been isolated but with a slightly more
unstable environment over the James River Valley, we could still
see an increase in thunderstorm coverage for a few hours yet this
evening before convection moves out of the area. Have updated
pops/sky cover and winds based on latest satellite and radar
imagery. Winds drop off pretty quickly behind the line of
convection moving through the area. There is a secondary surge of
higher winds pushing from Saskatchewan into northwest ND at this
time but not confident this will continue to spread much farther
south into the forecast area tonight as we lose daytime heating
and winds decouple. Updated products will be sent shortly.


.SHORT TERM...(This evening through Sunday)
Issued at 335 PM CDT Sat May 27 2017

A vigorous short wave was moving out of Southeast Saskatchewan and
into the north-central North Dakota with scattered showers and
isolated thunderstorms. Severe weather is not expected as low
level moisture is low. That dry low level (inverted V sounding) is
contributing to very gusty winds with the showers, as high as 50
mph. The subsidence behind the wave is strong and the timing would
end convection by 11 PM CDT with a quickly clearing sky to just
high cirrus. The wind was diurnally driven and too will quickly
drop off this evening.

For Sunday, similar. Diurnally driven winds increasing and under
cyclonic mid level flow look for convection again in the
afternoon. With no well defined mid level wave there should be
more distance between the showers on Sunday and they should be
more confined to the central and eastern parts of the forecast
area. temperatures, in a slightly cooler airmass, about 5 degrees
lower than today.

.LONG TERM...(Sunday night through Saturday)
Issued at 335 PM CDT Sat May 27 2017

Memorial Day looks partly sunny and cooler as the area remains
under the influences of cyclonic flow, and is deeper into the
cooler surface airmass. By mid week H5 ridging begins to nose in
over the area with temperatures back consistently into the 70s and
likely around 80 by weeks end. The ridge shows signs of breaking
down for next weekend with decent chances, we will see, of showers
and storms.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 628 PM CDT Sat May 27 2017

Convection with locally gusty winds just moving through KBIS at
this time, and will move into the KJMS area in the next hour.
This will bring the chance of Thunder with winds to around 45 mph
at KJMS 01-02 UTC. Otherwise VFR conditions through the forecast
period. Northwest winds diminishing this evening then increasing
once again late Sunday morning through the afternoon. Showers and
thunderstorms possible Sunday afternoon at KMOT, KBIS and KJMS.




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