Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KBIS 230820

Area Forecast Discussion
National Weather Service Bismarck ND
320 AM CDT Fri Jun 23 2017

.SHORT TERM...(Today and tonight)
Issued at 320 AM CDT Fri Jun 23 2017

GOES 16 non-operational water vapor imagery nicely shows cutoff
upper lows upstream over southwest Ontario and central
Saskatchewan, both slowly drifting southward in broad cyclonic
flow aloft. These features will help maintain the deep upper
trough over the Great Lakes region, leaving the Northern Plains in
continued cool northwest flow. Stratus deck currently in place
over much of the state, including some isolated showers, will
gradually erode during the day, though linger farther east closer
to upper low. Expect a breezy day, though winds will not be as
strong as on Thursday. Models are in decent agreement with
boundary layer winds on Friday around 25 knots and mixed layer to
around 700-750mb. Winds at top of mixed layer also are lower
today, 30-35 knots.

For tonight, will continue to carry low pops mainly across the
northeast as the second upper low, currently over Saskatchewan,
clips the eastern part of the state overnight. Otherwise, another
cool night expected with lows only in the 40s, and even some upper
30s across the southwest.

.LONG TERM...(Saturday through Thursday)
Issued at 320 AM CDT Fri Jun 23 2017

Continued cool on Saturday with somewhat lighter winds, but still
breezy. Upper level northwest flow continues with surface high
drifting across the Dakotas later on Saturday and Sunday. Will
continue to carry low pops across the northeast Saturday and
Sunday. Otherwise, highs will only be in the mid 60s Saturday and
slightly warmer, near 70 on Sunday. Cool nights will also continue
with lows in the 40s.

By Monday we begin to see a pattern change with upper level flow
flattening somewhat as upper trough pushes eastward and upper
level ridge begins to nudge closer to our region from the west.
Some differences begin to develop between global model height
fields, but potential exists for measurable precip by Tuesday.
Highs increase back to the 80s by Tuesday, possible into the 90s
if the GFS were to verify. Return flow by Tuesday increases low
level moisture return and instability with GFS sounding for KBIS
giving MLCAPE of 2800 J/KG, based on 95F high temp, however. ECMWF
is more conservative, around 1000 J/KG of CAPE. Timing of frontal
passage will be critical, with models hinting at most activity
across the eastern half of the state. Obviously, much uncertainty
for this time period, but the potential for better coverage of
showers and thunderstorms exists.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1228 AM CDT Fri Jun 23 2017

An area of mvfr cigs stretching from KISN/KDIK, will push into
KMOT/KBIS/KJMS during the 06z-15z Friday timeframe. Expect a return
to vfr cigs at all terminals 15z Friday through 06z Saturday. Gusty
northwest winds of between 20kt and 35kt will continue through
Friday afternoon, then abate after 00z Saturday.




AVIATION...KS is the U.S. government's official web portal to all federal, state and local government web resources and services.