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Area forecast discussion 
National Weather Service Grand Forks ND
635 PM CST Sat Nov 22 2014

issued at 635 PM CST Sat Nov 22 2014

Gaining some confidence in the forecast for tonight. Water vapor
imagery indicates a feature within central North Dakota...likely
responsible for the area of rain seen on radar. Did increase probability of precipitation
across the Devils Lake basin to 40% for this activity...but still
do not think it will be heavy or widespread. Rap indicates 925mb
temperatures increase this evening...and with all sites currently at or
above freezing will go all liquid for this activity. In
fact...wherever models indicate quantitative precipitation forecast tonight they also increase
925mb feel that the freezing rain threat is very
minimal. Thinking the only real chance for mixed precipitation will be
the leading edge of the deformation precipitation later tomorrow...but
even that threat appears minimal. Did adjust the grids to decrease
the mixed precipitation threat.

The other concern for tonight will be fog potential. Low
clouds/fog have already arrived into the southern Red River valley
and Wadena area. Hrrr/rap handling these ceilings best...and following
their lead most areas along and east of the valley will be
affected by midnight. Adjusted the sky grids...and expanded the
patchy fog mention. Not sure how dense fog will become...and will


Short term...(this evening through Sunday night)
issued at 317 PM CST Sat Nov 22 2014

Very tricky forecast tonight into Sunday. Will continue with Special Weather Statement
mentioning some light mixed precipitation tonight and then wind and snow
potential later Sunday into Sunday night.

Water vapor shows main upper low west of Regina Saskatchewan at middle
afternoon...and this will move east. Main snows with this north of the
upper low and this will translate east into central Manitoba
tonight into Sunday. Now just south and east of the upper low
there are several weak disturbances and light precipitation moving
through. These are not picked up by models very well. One area of
precipitation is in SW Manitoba into the Rolla area with light mixed
precipitation. Most of it is Canada and temperatures on the U.S. Side just above
freezing. Another wave with some light rain around Dickinson.
Unsure about this one as some models dry it up but would think
some chances of light precipitation making into parts of eastern ND later
this evening. Temperatures too a bit tricky as in warm sector so temperature fall
not great but they could drop into the 30-34 range making for some
tricky ptype issues. For now kept the broadbrush mixed precipitation
wording as given by top down method. Confidence is low tonight.
Also overnight northwestern edge of low clouds and fog may brush
far southeastern forecast area and some fog may spread into far
southeast and east central as well. 925 mb winds do turn a bit
more southwest tonight and suggest most of it will stay in dlh/mpx
forecast area.

For Sunday...not expecting too much to start but could be some
grunge and fog in the far east...but overall expect that very
moist airmass to be east of US with our area in 850 mb dry slot
Sunday morning. Surface low will move into southwestern Manitoba 15z
sun and then east along the border toward Warroad by sun evening.
Winds will turn northwest and increase quickly as low passes by
and some light snow will spread south. However...latest 12z and
18z model runs keep backing off on snow amounts it seems south of
the border with idea of 1-2 north of Highway 2 (if that) and then very
light amounts south of there. Wind with some falling snow will
result in low visibilities issues. But with models downplaying snow
amounts now unsure how far south snow will get and since main
threat is 21z and after Sunday will let Special Weather Statement ride.

Long term...(monday through saturday)
issued at 317 PM CST Sat Nov 22 2014

Cold and windy Monday with lingering light snow east and areas of
blowing snow in open areas even if just a light snow cover. High
pressure moves in Monday night. Next short wave to move southeast
into the area later Tuesday aftn/night. 06z GFS and 00z European model (ecmwf) quite
bullish with precipitation but 12z GFS now weak again and 12z European model (ecmwf)
weaker but still shows potential for accums with system mostly
Tuesday night.

For Tuesday night through Saturday...basically stay entrenched in
northwest flow aloft. Will have to deal with the first exiting
system Tuesday night. 12z GFS has now become the weakest model with the
European model (ecmwf)/Gem hanging onto precipitation the longest or into Wednesday morning. Then
there is model disagreement in how fast the next system spreads in
Wednesday night. European model (ecmwf) keeps surface high over the area while the GFS spreads
a swath of light snow across the far southern forecast area. Have gone more
with the GFS Route for now but kept chances quite low. Surface high
stays in control keeping it quiet but cold Thu/Fri. Could be a
little more light snow across the far south on Friday night or Sat but
again it looks pretty minimal.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 635 PM CST Sat Nov 22 2014

Rap/hrrr appear to be handling the low cloud/fog approaching from
the south. This guidance suggests these low clouds/fog will
continue to rapidly advect northward through the evening
hours...affecting sites along and east of the Red River valley.
Thus...IFR/LIFR conditions expected to move into the
kfar/kgfk/ktvf/kbji sites this evening...with a period of VFR
conditions for a good part of the day on Sunday before a cold
front brings windy conditions...snow showers...and at least MVFR


Fgf watches/warnings/advisories...

short term...Riddle
long term...godon/Riddle

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