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Area forecast discussion 
National Weather Service Grand Forks ND
250 PM CDT Tuesday Jul 28 2015

Short term...(this evening through Wednesday night)
issued at 250 PM CDT Tuesday Jul 28 2015

Wind speeds will be the main forecast challenge for tonight into
Wednesday. As of middle afternoon the most sun remained over the
southern Red River valley into west central Minnesota. Winds were from
the southwest...with the strongest winds yet over the western
Dakotas where they were gusting above 50 knots. Have not quite
reached Wind Advisory criteria from kdvl to kjms but should soon.
Still have large differences between the GFS and NAM for raw MOS
guidance...with the GFS much higher. Either way both models show
the strongest winds moving into the kdvl area between 00z and 06z
tonight. This is traditionally not the best time for mixing
stronger wind gusts down to the surface. Not seeing the best push of
cold advection during this time confidence not high
that advisory needs to be expanded or extended in time. Will
therefore keep the wind headlines as they are and let evening
shift keep an eye on things.

There are some showers over northeast Montana too which models hold
together in some fashion overnight. For this kept the idea of
some of this reaching the kdvl region around midnight and the
northern Red River valley toward Wednesday morning. This will then hang
around into northwest Minnesota into the day Wednesday. Also expect winds
to crank up again on Wednesday...but not as strong as they will be later
this afternoon and evening.

Long term...(thursday through tuesday)
issued at 250 PM CDT Tuesday Jul 28 2015

Models still showing some energy sliding into the northeast forecast area Thursday
afternoon into kept some low chances for precipitation with
this feature too. Possibility for anther weak wave Friday afternoon
but most models keep any precipitation associated with this in southern
Canada. Therefore will keep this time frame dry for now and see
what later models have in store.

Friday night through next Tuesday is looking pretty quiet with
temperatures near seasonal normals. There 500 mb upper ridge will
shift a bit east and our area will be in a bit deeper northwest flow
aloft. A couple of weak systems are poised to move through in this Saturday into Saturday night and again early next week.
However the airmass ahead of these systems will not as moist or
unstable and thus chances for organized convection is much lower.
So while there are some low precipitation chances in the extended
per the model blend...most areas get to enjoy a reprieve from the
humid and wet weather of late.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1245 PM CDT Tuesday Jul 28 2015

Unseasonably strong for middle Summer surface low and upper low will move
east across southern Manitoba the next 24 hours. As it does look
for winds to shift from a more southwest direction this afternoon
and evening to a more west direction overnight and then west-
northwest Wednesday. Big issue is wind speeds and how high.
Highest wind core aloft at 925-850 mb (40-50 kts) comes over NE ND
overnight and not at time of peak heating. Thus not expecting that
to reach the surface. However...enough gradient south of the surface low
for sustained winds of 20-30 kts in eastern ND/Red River with higher gusts
through the afternoon and through the night into Wednesday. A bit lighter
winds the farther east you go in northern Minnesota. High wind
gusts expected west of the Red River valley over higher
terrain...where around dvl some wind gusts over 40 kts possible late
this aftn-eve. Dry slot and clearing area will work east through
the area this afternoon/evening followed by a period MVFR or low end VFR
ceilings for a time overnight into Wednesday morning.


Fgf watches/warnings/advisories...
ND...Wind Advisory until 11 PM CDT this evening for ndz006-007-014-

Wind Advisory until 11 PM CDT this evening for ndz008-016-

Minnesota...Wind Advisory until 11 PM CDT this evening for mnz001-004-005-



Short term...godon
long term...godon/Riddle

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