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Area forecast discussion 
National Weather Service Grand Forks ND
937 am CDT Wednesday Aug 27 2014

issued at 936 am CDT Wednesday Aug 27 2014

Still a little bit of fog around but it should not last too much
longer. Expect quite a bit of Morning Sun with more late morning
and afternoon cumulus. Will only need to make minor cloud changes
as rest of forecast is looking good.


Short term...(today through thursday)
issued at 353 am CDT Wednesday Aug 27 2014

Today...surface high pressure in northern Minnesota will shift eastward
to the western Great Lakes...with subsident drying under an
approaching 500 mb ridge leading to generally fair skies and a light
southerly low level flow. Shallow and patchy fog early this
morning should burn off with sunrise leading to a seasonably mild

Tonight and Thursday...split flow in the polar jet stream has a
shortwave trough digging through the Great Basin and ejecting a weak
shortwave into the Central Plains from late Wednesday into
Thursday. For the northern plains... we can expect an increasing
southerly flow overnight tonight with scattered showers and
thunderstorms reaching across the southern half of the Red River
through the day on Thursday. Heaviest rainfall amounts should stay
well south of the area... nearer a quasi-stationary frontal band
across Nebraska and Iowa.

Long term...(thursday night through tuesday)
issued at 353 am CDT Wednesday Aug 27 2014

Thursday night and Friday...a shortwave trough in the northern
branch of the polar jet stream will slide across the northern
plains early on Friday... with a cold frontal system pushing
through the Red River basin during the day. Scattered showers and
thunderstorms are expected ahead of this system...put any deep
moisture return and related low level jet forcings are most
likely to stay engaged with the quasi-stationary frontal band in
the Central Plains states.

Saturday through Tuesday...long wave trough over the northwest
Pacific settles into western North America then shifts into
central Canada on day 7. Zonal pattern at the beginning of the
period becomes a little more meridional by the end of the period.
Pattern also shifts south a bit over the northern plains. Implying
jet stream to the north shifts south of the area by sun. Also
stability decreases.

Models in reasonable agreement at the beginning of the period. GFS
fast...NAM slow and European model (ecmwf) the compromise. GFS remains fast
through the period. GFS and European model (ecmwf) are quite out of phase at the
end of the period. Both the GFS and European model (ecmwf) have been trending
faster with the last couple runs. Will prefer the European model (ecmwf).


Aviation...(for the 12z tafs through 12z Wednesday night)
issued at 635 am CDT Wednesday Aug 27 2014

Expecting patchy fog across portions of northwest Minnesota and southeast
ND through sunrise...with light winds and clearing air behind VFR
cloud deck now pushing across the southern forecast area...into central Minnesota.
Local area will see light southerly flow today with a fairly dry
and stable airmass aloft. Some VFR cumulus formation is possible over
central Minnesota lakes this afternoon.


Fgf watches/warnings/advisories...


short term...gust
long term...gust/hoppes

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