Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 250555

Area Forecast Discussion
National Weather Service Bismarck ND
1255 AM CDT Sat Mar 25 2017

Issued at 1250 AM CDT Sat Mar 25 2017

Fine tuned the sky grids based on satellite.

UPDATE Issued at 937 PM CDT Fri Mar 24 2017

The area of stratus is not expanding westward as fast as earlier
thought so updated the cloud/sky forecast to maintain clear skies
a bit longer central tonight. The fog is also slow to develop but
starting to see temperature and dewpoint spreads close to
saturation at many locations and with an upslope component in the
windflow believe its juts a matter of time tonight. Delayed the
fog generally until after midnight.

UPDATE Issued at 635 PM CDT Fri Mar 24 2017

Am concerned about stratus area across the James River Valley
north through the Devils Lake Basin which appears to be expanding
westward in broad low level easterly flow. Expanded the clouds a
bit more into Bismarck and Minot tonight. Otherwise current
forecast looks ok.


.SHORT TERM...(This evening through Saturday)
Issued at 310 PM CDT Fri Mar 24 2017

A progressive pattern both in the short and long term period will
result in several fast moving systems with chances for precipitation
nearly every other day.

The latest suite of satellite imagery shows a mostly clear sky
across western and central ND this afternoon, with some cumulus
sprouting up in western ND. Webcams indicate shallow fair weather
cumulus, and this should be the extent of it as a mid/upper level
ridge and associated subsidence aloft continues to propagate
through this afternoon. By tonight, the ridge shifts east with a
southwest flow and low level warm air advection ensuing. With
increased vertical motion, expect an increase in mid/high clouds
per GFS 700-300mb RH field, mainly in the west and northern portions.
Latest HRRR visibility forecast maintains the development of fog
mainly along and east of the Missouri River tonight, especially
where we have the ongoing snowpack in the north central. However,
if clouds become thick enough overnight across the north, the fog
would likely be tempered a bit and reside farther south and east
from our current gridded forecast.

Current water vapor shows a shortwave trough along the northwest
coast with several lead shortwaves set to begin moving into
southwest ND early Saturday. These shortwaves will then move from
southwest to northeast throughout the day Saturday. At the surface,
low pressure forms in eastern Wyoming early Saturday morning and
shifts across southern South Dakota Saturday afternoon and evening.
An inverted surface trough from this surface low reaches into
western ND Saturday, which links up with a cold front sweeping
through central Saskatchewan. This cold front weakly extends into
north central ND, with a surface convergence setting up from
southwest to north central by afternoon. Thus will continue with a
chance for rain in the afternoon southwest through north central ND.
Afternoon highs will range from around 40F Turtle Mountains to
lower 60s southwest.

.LONG TERM...(Saturday night through Friday)
Issued at 310 PM CDT Fri Mar 24 2017

Chances for precipitation continue Saturday night north central/Turtle
Mountains and into south central ND as the convergence boundary
via the inverted surface trough to our south, and the Canadian
cold front to our north, propagate east. NAM BUFKIT soundings
sampled at Minot/Rolla/Devils Lake/Carrington/and Jamestown show
surface temperatures just above freezing late Saturday night,
with the exception of a couple hours before sunrise Sunday. That
being said, this leaves a small window of opportunity for light
freezing rain, but areal coverage this forecast cycle has shrunk
quite a bit from previous. At this point, would expect patchy/light
freezing rain from the Turtle Mountains into the northern James
River Valley, but not enough confidence to warrant advisory
criteria being met at this time. Future shifts can re-evaluate
this potential for any changes. Elsewhere, expect a high chance to
likely pops for rainshowers Saturday night through Sunday morning.
Although the probability for precipitation becomes less during
the afternoon, expect additional showers to develop as the main
mid/upper level shortwave slides through.

Beyond Sunday, expect a series of transitory ridges/troughs to
slip by with periodic chances for rain/snow at night and
rainshowers during the day. Nothing significant in terms of
precipitation amounts or a long duration event. Right now, expect
dry weather Monday into Tuesday morning, then chances for
precipiation increase from west to east Tuesday afternoon through
Wednesday. Thursday appears dry with the next system possible by
Friday into Saturday per GFS. The ECMWF keeps this system to our
south. High temperatures are forecast to remain above normal next
week with highs mostly ranging between 45F and 55F west and
central, and some 60s expected across the southwest.


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1250 AM CDT Sat Mar 25 2017

VFR at KDIK and KISN through the forecast period. A band of IFR
ceilings was pushing west-northwest from KJMS to near KBIS and
into KMOT. The back edge was just east of KJMS and will expect
clearing there by 25/08Z. Questionable whether or not these clouds
make it in to KBIS. Patchy fog is possible but not likely over the
east half until 25/15Z. Wind shear possible KISN-KMOT-KDIK


Issued at 310 PM CDT Fri Mar 24 2017

The continuation of a relatively benign spring melt season continues
as the spring melt is now upon the Souris (Mouse) River basin.
Thus far, minor flood stage has been reached only at the Souris
River below Lake Darling forecast point, but minor flooding is
expected to spread as snow melt in Canada initiates runoff and the
melt rate in North Dakota hits its stride over the coming days.




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