Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 300238

Area Forecast Discussion
National Weather Service Bismarck ND
938 PM CDT Sat Apr 29 2017

Issued at 937 PM CDT Sat Apr 29 2017

Clouds over the northwest continue to diminish, though some high
cloud cover has been surging in from the south. Latest guidance
continues this surge through around midnight, then starts shifting
it off to the east. Have updated forecast to address this.
Otherwise, going forecast is in good shape.

UPDATE Issued at 617 PM CDT Sat Apr 29 2017

A broad swath of cloud cover had developed over northern and
western portions of the area in weak cyclonic flow aloft and
strong mixing. Expect these clouds to be primarily diurnally
driven, so should dissipate later this evening. As for
precipitation, only expect a few sprinkles may reach the ground if
anything given the dry lower levels. Otherwise, a pleasant quiet
evening is expected.


.SHORT TERM...(This evening through Sunday)
Issued at 325 PM CDT Sat Apr 29 2017

Currently, North Dakota was beneath a weak flow aloft, with a large
upper level low over the 4-Corners/west Texas area, another low
over central Saskatchewan/Manitoba, and a third shortwave
low/trough over northern Alberta. Surface winds were mainly
southerly. Temperatures had climbed into the upper 50s/lower 60s.

Regarding fire weather: relative humidity values ranging widely
from around 15-20 percent in most of central ND to around 30-35
percent over northwestern ND. This is likely due to the lingering
dry but cool surface high pressure ridge axis along southern ND into
eastern ND, across northern MN into Ontario.

The upper level low in the southwest US is forecast to move/develop
eastward and deepen across the southern Plains. Meanwhile the
Alberta shortwave moves east into the Canadian Prairies. As it does,
a surface low develops over southern Alberta and moves east into
southern Saskatchewan. A surface trough extending south from the low
moves east across Montana. The models indicate drying at lower
levels ahead of this trough. Expecting the highest temperatures
Sunday in the northwest (mid 60s) ahead of this trough with
southerly winds and driest air allowing good mixing. The lowest
temperatures are expected in the James Valley (mid 50s) with
northeasterly winds develop in response to the developing southern
Plains storm.

Fire weather conditions Sunday: With the drying ahead of the
advancing trough, expect afternoon relative humidity values to drop
below 20 percent along the ND/MT border, with 20 to 25 percent
values across much of central ND. The exception would be the James
Valley, where relative humidity values should be around 30

.LONG TERM...(Sunday night through Saturday)
Issued at 325 PM CDT Sat Apr 29 2017

A more active pattern sets up for the first part of the long term,
followed by above normal temperatures to end it.

The upper level low continues to deepen and moves out of the
southern Plains and lifts northward into Iowa by late Sunday
night/Monday morning. This stacked system then continues towards the
central Great Lakes Monday afternoon. As the low moves toward Iowa
it spreads its precipitation shield into the southeast part of the
Bismarck NWS forecast area, the Dickey county area. This will make
for a period of wet weather Sunday night and Monday there. Also, a
short wave approaching from the west brings rain chances to the
western half of the forecast area coincident for Sunday night
through Tuesday night. Enough instability is forecast for Monday
afternoon that thunderstorms were included for monday afternoon west.

Ridging builds in behind the exiting shortwave with temperatures
warming through the 60s and lower 70s for highs for the end
of next week, along with low temperatures above freezing.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 617 PM CDT Sat Apr 29 2017

VFR conditions through the forecast period.




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