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Area forecast discussion 
National Weather Service Grand Forks ND
955 am CDT Tuesday Oct 21 2014

Update...
issued at 951 am CDT Tuesday Oct 21 2014

No changes needed. 12z NAM shows strongest 925 mb winds (50 kts)
over the Red River valley 00z-06z and at this time the inversion
will be setting up. During the time of maximum heating winds to mix
are in the 35kt range...a tad higher up around Hallock-Pembina.
Thus forsee windy conditions but just below advisory levels.
Possible exception is small area around Pembina-Hallock. Full sun
today and temperatures appear OK. &&

Short term...(today through wednesday)
issued at 400 am CDT Tuesday Oct 21 2014

The main challenge will be winds today then precipitation chances late
tonight through Wednesday night. Models are in good agreement...the GFS
seems a bit too fast with the Wednesday system...so will side with the
NAM/European model (ecmwf) this morning.

For today...expect a windy day in the valley and points west by
afternoon. There will be 35kt to mix from about 900mb in the
19-23z timeframe...and winds could briefly touch advisory levels
with gusts to around 40 miles per hour. For now will hold on a Wind
Advisory...but something the day shift can monitor. Temperatures should
warm nicely with nearly full insolation.

For tonight...winds will remain in the windy/breezy category
through the night with 50kt low level jet developing. There will some
elevated instability moving into the west and south late...with
showalters around 3c and even some 850mb cape around 600 j/kg.
This coupled with middle level warm air advection should promote some elevated
convection with showers at least. There could be some thunder as
well...but for now will just mention a few showers into the south
and west after 9z.

On Wednesday...a band of middle level fgen and a shortwave will move
through from west to east. Deeper layered saturation should occur
by afternoon into the valley...then move east around 00z Thursday.
There should be a band of showers developing by afternoon in
eastern ND...moving into western Minnesota into Wednesday evening. Can/T rule
out a few lightning strikes mainly east of the valley with precipitable waters
around 1.20 and strong 850mb moisture transport. For now will keep
it showers but may eventually need to add some isolated thunder if
model trends continue.

Long term...(wednesday night through monday)
issued at 400 am CDT Tuesday Oct 21 2014

For Wednesday night...the rain shower band will shift into the Minnesota
counties after 03z Thursday...then out of the forecast area by 12z Thursday.

For Thursday...a dry day is expected with highs once again well above
normal with temperatures in the low/middle 60s.

For Friday through Monday...long wave trough off the West Coast of North
America and long wave ridge over the western Great Lakes at the
beginning of the period. Pattern deamplifies and becomes more zonal
through the period. GFS and European model (ecmwf) were in reasonable agreement at
84 hours. The European model (ecmwf) upper air was faster than the GFS at day
7...timing of surface features were in good agreement at day 7
however the European model (ecmwf) solution was farther north. Will blend the GFS
and the European model (ecmwf).

Cold front/wind shift is is expected to move through Friday as short
wave trough move across southern Canada. Will trim back probability of precipitation on sun
and Sun night.

High temperatures generally increase one or two degrees on Friday and Sat and
one to four degrees on sun and Monday from yesterdays model runs.

&&

Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 615 am CDT Tuesday Oct 21 2014

The main challenge will be increasing southeast winds today. Winds
should gust to around 35kt by this afternoon at most sites...and
continue into tonight. There will be some increasing middle/high
clouds overnight...but VFR conditions expected.



&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Update...Riddle
short term...dk
long term...hoppes/dk
aviation...dk

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