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Area forecast discussion 
National Weather Service Grand Forks ND
706 PM CST Tuesday Nov 24 2015

issued at 659 PM CST Tuesday Nov 24 2015

Very tricky forecast. Model soundings and various short range models
do have a saturation in the sub 850 mb layer overnight...mostly
late tonight into Wednesday morning. So idea of low cloud development
does seem reasonable. Just using 925 mb relative humidity not working as GFS
would have low clouds now is using that. The hrrr would argue
lower ceilings will drop south with the front into NE ND overnight and
reach southeast ND/west-central Minnesota past 12z. With uncertainity did keep Post
06z probability of precipitation/weather the same as previous forecast but lots of uncertainity. The
main 850 mb moisture plume will shift a bit more east overnight
with the MVFR clouds moving north through eastern Kansas more destined
for southern Minnesota into western WI Wednesday morning. Did raise lows a tad and
did go dry through 06z.


Short term...(this evening through Wednesday night)
issued at 302 PM CST Tuesday Nov 24 2015

Challenge for tonight into Wednesday night remains drizzle and or
freezing drizzle with the timing and light snow with frontal passage tomorrow.
Moist near surface layer to develop tonight...along the frontal boundary
is an area with high confidence. Another possible area...lower
confidence...continues to be the southern valley and into west
central Minnesota. Areas where it does develop may create the
possibility for some drizzle or freezing drizzle with the dry layer
aloft. Early Wednesday the frontal passage moves from northwest into the
valley by 12 to 15z and through the southeast during early afternoon. The
light drizzle or freezing drizzle will turn over to light snow with
any drizzle or snow accumulations to be minimal. Some widely
scattered icy spots remain possible though travel impacts are
expected negligible.

Long term...(thursday through tuesday)
issued at 302 PM CST Tuesday Nov 24 2015

Thanksgiving day will be relatively cold with northerly surface winds
bringing in 925mb temperatures at 10c to 15c below zero. This will
produce daytime highs in the middle 20s. Surface highs continue to build
into the forecast area with clearing skies for Thursday afternoon in to the
overnight. Some temperature recovery as surface winds turn to the SW and full
sun is expected Friday afternoon bringing maximum temperatures to near 30.

Friday night through Tuesday...the first part of the period should
be fairly quiet as the blocked pattern continues and the cut off low
is still wobbling over the western Continental U.S.. the models all start
bringing the cut off out into the plains Sunday/Monday...although
differ in the details. Continued to keep the low probability of precipitation that the
blended solution gives US for Sunday night and early next week given
the lack of certainty with blocking systems. Temperatures should be back
above seasonal averages.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 659 PM CST Tuesday Nov 24 2015

Low confidence taf forecasts for the overnight into Wednesday morning
in regards to development of light fog and IFR ceilings. Kept previous taf
idea in tact but pushed back timing a bit to more after 08z-10z
period for IFR ceilings at taf sites. Fzdz chances there but high
degree of uncertainity in coverage and if any forms. Wind shift to
the northwest reaching dvl 10z or so and the Red River 12-14z and bji
17z or so.


Fgf watches/warnings/advisories...


short term...jk
long term...jk/Jr

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