Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 242353

Area Forecast Discussion
National Weather Service Bismarck ND
653 PM CDT Sat Sep 24 2016

Issued at 637 PM CDT Sat Sep 24 2016

Surface and upper level low pressure will lift northeast across
the forecast area tonight into Sunday morning. Currently the
surface low is situated over west central ND with the upper low in
far southwest ND. Cold front has made it through northwest ND and
should move across the southwest this evening as the surface and
upper low finally begin to lift northeast.

For the early evening update we adjusted pops/weather based on the
latest radar and satellite analysis. Basically a slower trend
through the night. Day shift had delayed the start of the wind
advisory in the southwest until 7 pm MDT and this looks reasonable
as winds are beginning to move into the northern portion of the
advisory. Will send out updated hazard and text products shortly.


.SHORT TERM...(This evening through Sunday)
Issued at 253 PM CDT Sat Sep 24 2016

Deep cut off upper level low was centered around southeastern
Montana at 18Z with the associated surface low over southwestern ND.
Dry slot of system was supporting mostly dry conditions across
south central ND Saturday afternoon with low level southerly flow
in the warm sector helping increase instability. Dew points in
this area were mainly in the mid/upper 60s and SB CAPE around 1500
J/Kg. High res models show convection developing after 20Z, with
the HRRR showing the stronger cells just outside our area. Any
severe threat should be relatively short lived and over by 00Z
Sun. Also expect showers and stratiform precip to spread from west
to east overnight as upper low progresses across the state,
reaching southern Manitoba as an open trough by 18Z Sun.

Expect strong winds to develop behind the system as the surface
low reaches northcentral ND this evening. Wind advisory that is
in effect tonight for the extreme southwest will be expanded to
the north and east. Will also make some adjustments to the
starting time as winds will be a little slower to strengthen than
originally thought. GFS depicts strongest BL winds around 40 kts
over this area. 0.5 km AGL winds also max at around 50 knots near
Adams/Sioux counties at 09Z.

On Sunday, precip will end from west to east and should be
completely out of the area by late afternoon. Breezy to windy
northwest winds will continue through the day as the low pushes away.

.LONG TERM...(Sunday night through Saturday)
Issued at 253 PM CDT Sat Sep 24 2016

A longwave upper level ridge will build over the Plains during the
week leading to mostly dry weather along with a warming trend. High
temps initially in the 60s on Monday will warm to the low 70s on
Tuesday, with similar highs through Friday.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 637 PM CDT Sat Sep 24 2016

A low pressure system over western ND will lift northeast across
central ND tonight and into eastern ND Sunday morning. At the
beginning of the 00Z TAF period, VFR conditions with a southerly
flow at KJMS KBIS and KMOT ahead of the low. Strong northwest flow
at KISN with mvfr ceiling and rain showers, and poised to push
into KDIK within the next 1-2 hours. MVFR-IFR and possible LIFR
ceilings will spread west to east across central ND TAF sites
tonight, with winds shifting northwest and increasing. Conditions
will improve quickly Sunday morning at each site from west to
east. VFR conditions at all sites by Sunday afternoon, but still
strong northwest winds through 00Z Monday.


Wind Advisory from midnight CDT /11 PM MDT/ tonight to 6 PM CDT
/5 PM MDT/ Sunday for NDZ019-020-034-042-045-046.

Wind Advisory until 6 PM CDT /5 PM MDT/ Sunday for NDZ017-018-



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