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Area forecast discussion 
National Weather Service Grand Forks ND
335 PM CST Thursday Dec 18 2014

Short term...(this evening through Friday night)
issued at 323 PM CST Thursday Dec 18 2014

Main issue is clouds and low precipitation chances over the next several
days as a weak upper trough moves through. This afternoon water
vapor shows a 500 mb trough over central ND. This will move slowly
east and be into northwest Minnesota Friday. Area of clouds associated with this
system over most of the forecast area at this time. Not much precipitation as
deeper moisture is not present. But got a layer of middle level
moisture and some low level moisture present tonight as trough
moves into eastern ND. Radar shows a few weak returns right near the
Minot and Bismarck radar sites and was a few reports this afternoon of
light mist in north central South Dakota and earlier today near Bismarck.
Think as this upper system moves east enough low level moisture
for a few flurries. BUFKIT soundings indicate some potential for
freezing drizzle in far southeastern ND tonight so included. Upper
trough slowly moves into northwest Minnesota Friday and will continue with
flurry mention and continue a flurry/freezing drizzle combo in
parts of west-central Minnesota as BUFKIT soundings indicate a chance of that
mainloy Fergus Falls-Wadena areas. Overall though expect a cloudy

Friday system will slowly exit to our east with lingering flurries or
light snow chances in eastern forecast area. All in all only very light

As for temperatures went a tad warmer than most guidance for lows due to
clouds. Afternoon temperatures to warm up slowly into the 20s to around 30.

Long term...(saturday through thursday)
issued at 323 PM CST Thursday Dec 18 2014

Saturday will see a break in the precipitation but clouds likely tough to
get rid of. Sat night into Sunday will see next upper short wave
to drop southeast into the area giving once again some light
precipitation chances mainly for the Red River into Minnesota. Once again
soundings would show some threat for a fzdz/-sn mix with this
system Sat night so included to match up with weather forecast office dlh. Temperatures this
weekend to be mild running 10-15 degrees above normal.

Long wave ridge/trough over western North America/Mississippi River
valley respectively will amplify through the period. More so trough
digging day5 and thereafter. The GFS was faster than the European model (ecmwf)
through much of the period. Upper level jet forecast to dig trough
over the plains Monday through Wednesday. Both the European model (ecmwf) and GFS were
trending farther north with the last couple model runs. Will prefer
the European model (ecmwf).

High temperatures were increased on Monday by a degree or so. Temperatures were
lowered one or two degrees on Tuesday and high temperatures were increased one
to four degrees on Wednesday and Thursday.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1112 am CST Thursday Dec 18 2014

As high pressure drifts east...the area will see light S to southeast
winds continue through the next 24 hours. Based on the latest
trends and model data...lower MVFR to IFR ceilings will be increasing
over much of the area over the next 6-12 hours. The NAM MOS data
support ceilings below 1000 feet...with NAM bufr soundings saturated in
the low leves as well. Some ceilings may dip below 500 feet by late
tomorrow morning according to the NAM MOS. Have not included ceilings
this low yet...but will need to monitor trends and model data to
see if the likelihood increases.


Fgf watches/warnings/advisories...


Short term...Riddle
long term...hoppes/Riddle

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