Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

256
FXUS63 KFGF 301835
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1235 PM CST Wed Nov 30 2016

.UPDATE...
Issued at 1235 PM CST Wed Nov 30 2016

Light snow continues across much of the RRV and into eastern ND.
Some enhanced returns on radar have been headed southwestward
towards the Cooperstown/Valley City area, so bumped up POPs to
categorical for a while longer over mostly central and southern
counties. Increased snow amounts a bit over the south where there
have been reports of near 1 inch in Fargo. The high res models
continue to show a decreasing trend into the afternoon, so have a
slow decrease in POPs. Mostly snow early on, but some drizzle rain
mixing in at some spots where temps are expected to climb, and
freezing drizzle possible in the north later in the day as drier
air aloft starts to move into the area.


&&

.SHORT TERM...(Today and tonight)
Issued at 258 AM CST Wed Nov 30 2016

Primary forecast challenge for today and tonight continues to be
precipitation type with a mix of very light rain, drizzle or
freezing drizzle and snow the most likely scenario for this
morning...and precipitation ending or turning to mainly drizzle
in the afternoon hours. Surface low currently vcnty of St Cloud MN
with upper low between Duluth and Minneapolis. The weakening
deformation zone remains west of the forecast area and is
weakening rather than pulling eastward as the low moves into the
GTLKS region.

Today...Models indicating band of higher QPFs over central ND
begin to weaken in the 09Z to 12Z timeframe...and all but
disappear by 18Z. Light QPFs up to 0.05 inches continue
throughout the day due to a supersaturated near surface layer.
Higher QPF values in the tri-state border region vcnty of upper
vort max over Sioux Falls. Current wet bulbs are warm enough that
most precipitation should fall as rain as snow falls through the
warmer near surface layer and melts...although snow is possible
where temps are in the 32 F to 34 F range. By this afternoon,
models continue to suggest a drying mid layer that will cut off
ice presence and should begin to turn p-types over to drizzle.
Therefore before 18Z look for mainly rain or snow with patchy
drizzle and fog...transitioning to a very light freezing drizzle
or snow as surface temperatures cool a degree or two by evening.
Overnight expect mainly freezing drizzle by midnight unless the
near surface layer dries out enough to end precipitation. Will
keep the mention of FZDZ for the overnight hours with trace
amounts of ice accumulation by Thursday morning.

.LONG TERM...(Thursday through Tuesday)
Issued at 258 AM CST Wed Nov 30 2016

Thursday through Friday night...low layers of the atmosphere
finally dry out as a much drier and colder airmass sinks over the
valley. Daytime highs will be a deg or two cooler than today but
will decline sharply tomorrow night, with model guidance
suggesting lows in the mid to low 20s...possibly into the upper
teens in the far northwest. Much of tomorrow night will be mostly
cloudy so overnight lows are possibly too cold but with decent
cold advection no plans to deviate from guidance. Surface high
remains over western ND so we will also have light NW winds,
preventing temps from bottoming out. Friday and Friday night
temperatures should be a deg or so cooler than Thursday despite
winds turning more westerly by mid Friday afternoon. Continuation
of some cloud cover Fri night will once again keep overnight lows
in the 20s, possibly upper teens where winds are the lightest in
the far west.

Saturday night through Thursday...Look for the extended period to
have a tranquil start...with light winds and high temps on
Saturday in the upper 20s and low 30s.

By Saturday and Saturday night...high pressure continue to retreat
toward the Ohio valley with return flow across the region ahead of
the next system. A trof of low pressure will cross the area on
Sunday...but limited moisture will result in some light snow with
little accumulation expected.

Otherwise...a more organized system looks to develop by late Monday.
Southerly winds should become a bit breezy with a tightening
pressure gradient...and temperatures will be slightly warmer. Some
precipitation should occur right at the end of the forecast
period...with mainly light snow as the predominate precipitation
type.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1235 PM CST Wed Nov 30 2016

Ceilings have been fairly steady around 700-1000 ft, but
visibilities have been all over the place with light snow showers
moving through. Most locations seeing light snow have 2-5SM, but a
few spots have been down to 1SM at times. Snow will taper off this
afternoon, but then some -FZDZ will be possible at times
overnight. Included FZDZ mention at most TAF sites with around
3-5SM vis and ceilings around 800-1000 ft. Freezing drizzle will
decrease by the end of the period, and visibilities should come up
to P6SM. Ceilings will stay IFR/low MVFR however through the end
of the period. Winds will stay out of the north to northwest with
speeds this afternoon around 12-15 kts going down to less than 10
kts by tomorrow morning.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&

$$

UPDATE...JR
SHORT TERM...Speicher
LONG TERM...Hopkins/Speicher
AVIATION...JR



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.