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fxus63 kdlh 220008 

Area forecast discussion
National Weather Service Duluth Minnesota
608 PM CST Thu Nov 21 2019

issued at 556 PM CST Thu Nov 21 2019

Updated for the 00z aviation discussion.

Cloud cover and flurries are going to be the main concern for the
next 12-18 hours. Model guidance has been very optimistic in
reducing cloud cover and ceilings during the overnight time frame,
which considering the time of year, and how extensive the existing
cloud cover is, have increased cloud cover for overnight tonight
significantly over the previous forecast. This will likely have
some effects on the temperature forecast as well, but will have to
revisit that later on this evening as I see how well the sky cover
change is going.


Short term...(this evening through Friday night)
issued at 355 PM CST Thu Nov 21 2019

A cold front stretched from Eastern Lake Superior into central
Wisconsin this mid-afternoon with another area of low pressure
near Green Bay. A cold front then trailed southwest from this low
to the Southern Plains. The bulk of the snow showers have shifted
east of the Northland, but persist across north-central Wisconsin.
Additionally, light anthropogenic snows were seen from the Iron
Range to near the twin ports. High pressure will build in from the
west overnight which will lead to clearing skies and bring an end
to any lingering snow showers. Winds are expected to back to the
west-northwest this evening, which will shut off the lake-effect
snows over the Iron County snowbelt in Wisconsin. Any additional
snowfall amounts will be under an inch, although the Hurley-Gile
area may seen another inch or two. Lows tonight will cool into the
teens and high single digits.

High pressure will then pass by to the south for Friday and Friday
night. A weak shortwave will approach the Northland Friday night,
which will lead to a slight increase in clouds in our northwestern
zones, but any precipitation will remain north of the
international border. Highs Saturday will reach into the upper 20s
to middle 30s with lows Saturday night in the upper teens to lower

Long term...(saturday through thursday)
issued at 355 PM CST Thu Nov 21 2019

A fairly quiet weather pattern is expected though with some caveats.
Current model guidance largely keeps the region unscathed over the
next week sending the larger systems both north and south of the

There is some potential for a system to the north to bring
accumulating snowfall to the Minnesota arrowhead (very similar to the
locations impacted by the system exiting the area today) on Monday
morning. This will be fueled by an upper level feature that will
cross Ontario with the main difference being the surface low will be
north of the international border rather than in Wisconsin. I don't
think a whole lot of accumulation is expected - perhaps a few inches
of snow as it sips its moisture from a Continental air mass.

Attention then turns to a larger system that appears for the time
being to skirt across the Central Plains and into the lower Great
Lakes during the Wednesday timeframe. This may be an issue if you
have travel plans that bring you into the Nebraska to Iowa to
Illinois to lower Michigan to Ohio to Pennsylvania areas. You'll
probably be OK if you are sticking close to home in Wisconsin and
the Twin Cities areas. This system is strongly forced and could
create quite the ruckus, but again not much potential for impacts
in the Northland. It's something to keep an eye on though in case
the storm track shifts more northward. Downplayed some of the
higher pops model blends were giving as they appeared to have some
inertia from prior runs that brought the storm closer to home.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 556 PM CST Thu Nov 21 2019

Cloud cover and flurries are going to be the main concern for the
next 12-18 hours. Expect the stratus that is visibile on satellite
to be very persistent overnight and have maintained the broken-overcast
MVFR ceilings through at least 09z tonight, with a gradual
clearing to VFR trend from west to east through 14z. There should
also be some flurries under the stratus, and have included vcsh
groups for now as well. The remainder of the taf period should be
VFR with winds gradually shifting from the northwest of issuance
time through west and then southwest by approximately 18z.


issued at 355 PM CST Thu Nov 21 2019

A low pressure system exits into the eastern Great Lakes this
evening giving gusty northwest winds. The pressure gradient relaxes
tonight before increasing again on Friday as high pressure builds to
the south and causes more west to southwesterly winds across the
lake. Waves will decrease to around 1 to 3 feet before rising some
Friday as the westerlies increase, but the larger waves should
remain in the offshore waters.


Preliminary point temps/pops...
dlh 14 31 22 34 / 0 0 0 0
inl 10 33 23 33 / 10 0 0 10
brd 15 35 23 37 / 0 0 0 0
hyr 15 32 21 36 / 0 0 0 0
asx 18 33 23 37 / 10 0 0 0


Dlh watches/warnings/advisories...
WI...Winter Weather Advisory until 6 PM CST this evening for wiz004.

Ls...Small Craft Advisory until 10 PM CST this evening for lsz146>148.

Small Craft Advisory until 4 am CST Friday for lsz140-141.



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