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Area forecast discussion 
National Weather Service Bismarck ND
1243 PM CDT Monday Jul 28 2014

issued at 1236 PM CDT Monday Jul 28 2014

Clouds continue to develop over central into portions of western
North Dakota. Early afternoon update will up cloud cover towards
current trend. Otherwise...going forecast is on track.

Update issued at 927 am CDT Monday Jul 28 2014

Patchy fog has dissipated over the area so have removed that from
the forecast. Otherwise...current forecast is on track. Will keep
low probability of precipitation going around the Minot area as models continue to suggest
a few light showers possibly developing with weak approaching
wave...but will re-evaluate it later today. Updates have been sent.

Update issued at 627 am CDT Monday Jul 28 2014

Morning lows so far close to 40 degrees south central. Patchy fog
continues across the region with some low/middle clouds associated with a
weak middle level impulse streaming across the north central. So far
current forecast trending well.


Short term...(today and tonight)
issued at 350 am CDT Monday Jul 28 2014

Northwest flow almost always presents a challenge...and the short
term concern today will be the development and extent of isolated
showers from southeast Saskatchewan into north central North Dakota.
In the near term this morning...patchy fog can be expected over
western and central North Dakota.

The latest water vapor imagery shows a shortwave which has
initialized well with the NAM/GFS near Prince Albert Saskatchewan.
This shortwave is forecast to slide into southeast Saskatchewan and
into north central North Dakota by 18z today. Middle level vorticity
advection is more or less channeled resulting in a lack of strong
vertical motion/weak differential positive vorticity advection.
However per fog/stratus loop and surface observations...850mb-700mb
moisture is already in place and will continue to remain in tact
through most of the afternoon per model guidance. Lapse rates in
the 850mb-700mb layer in the north central are forecast between
6.5c/km to 7c/km early this afternoon with a couple hundred joules of
cape forecast at Minot. With the NAM and other high resolution NAM
based models indicating some potential for light quantitative precipitation forecast over north
central North Dakota...have decided to mention isolated showers
from around Minot to Sherwood from late morning into the early

With the exception of the west which will remain sunny...the rest
of the forecast area will once again see scattered to broken cumulus clouds
at times. Have utilized a blend of the rap13/hrrr/nam12 for sky grids.
Highs today will range from the middle 70s north to lower 80s west. A
mostly clear sky is expected Monday night with lows 50 to 55.

Long term...(tuesday through sunday)
issued at 350 am CDT Monday Jul 28 2014

Blocking flow continues to dominate the weather for the extended
period with a large and persistent longwave trough over the
eastern US and a ridge across the west. This will leave the
northern plains on the eastern side of the h500 ridge in northwest
flow aloft. Models are showing a quiet weather pattern for the
region through Friday with a bit more activity making its way
into the region over the weekend as several shortwave features
make their way through the ridge into the region. That being
said...have raised the sky cover across central North Dakota
Tuesday and Wednesday to partly cloudy in anticipation of the
northwest flow conundrum for the northern pains. Summertime
northwest flow often can bring weak shortwave elements through
resulting in isolated showers or a thunderstorm. BUFKIT soundings
for the NAM suggest there will be shallow cape between 5 and 10
thousand above ground level that is capped above. While showers could be an
issue...more likely there will be sufficient shallow instability
for the formation of widespread cumulus field capped above 10k. So
added the clouds for partly sunny instead of sunny. Otherwise
should see a slow warming trend this weak with scattered to
isolated thunderstorms over the weekend period.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1236 PM CDT Monday Jul 28 2014

VFR conditions will continue through the forecast period with 4000
to 6000 foot ceilings over much of central into portions of
western North Dakota.


Bis watches/warnings/advisories...


short term...Kansas
long term...warm air advection

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