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fxus63 kdlh 161006 
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Area forecast discussion
National Weather Service Duluth Minnesota
406 am CST Mon Dec 16 2019

Short term...(today through tuesday)
issued at 404 am CST Mon Dec 16 2019

Persistent flurries and light snow remain over the area this
morning, which appears to be associated with the strong warm air
advection that is slowly moving across the region this morning in
the 925 to 850mb layers. Few models are picking up on this snow,
and the radar returns are on the weak side, but observations of snow
and MVFR visibilities extend from Crane Lake south through the twin
ports, and around Leech Lake east to Ashland. The warm air
advection should move out of the area during the early morning
hours, and allow the snow to come to an end. Have maintained some
high pops with low quantitative precipitation forecast through this morning to cover it. The clouds
assoicated with it have kept temperatures on the mild side,
generally ranging from 5 to 15 above. Today a weak cold front will
drop through the area, which should act to shut off the snow, and
should allow some clearing in the clouds cover during the daytime.
Cold temperatures will linger though, and highs should only get into
the 10 to 20 degree range. Tonight another round of light
snow/flurries should move across the area as second wave of warm air
advection and moisture moves across the area, accompanied by a
shortwave the moves through the northwest flow aloft. The models
have been depicting some small qpf, so I have put in some chance
pops across the northern portions of the forecast area, which are on
the high end of guidance, and while I even bumped things up a bit as
well, I suspect may need it higher yet for tonight. This light snow
is unlikely to have much of an impact, but people will notice it if
they are out tonight. This shortwave moves east of the area by
Tuesday, but we will be undergoing some fairly strong cold air
advection, and we should have yet more flurry/light snow chances for
parts of the area on Tuesday. Temperatures will remain on the cold
side for tonight and Tuesday, though the clouds will have a
mitigating effect.

Long term...(tuesday night through sunday)
issued at 404 am CST Mon Dec 16 2019

The overall trend of the extended remains quiet with cold conditions
to start before warming heading into the weekend. Parts of northwest
Wisconsin stand a decent chance of reaching the freezing mark or
slightly above for Sunday into Monday. Still no major systems
through the period with inly a few chances for light snow.

A strong upper low will pass to the east of the region Tuesday night
into Wednesday as surface high pressure moves over the Northland.
This will lead to clearing skies and light to calm winds allowing
for excellent radiational cooling conditions. Lows will fall into
the single digits and teens below zero in northwest Wisconsin with
teens and 20s below zero in Minnesota. Winds may not subside
completely across the Minnesota arrowhead and this may lead to wind
chills in the 25 to 35 below zero Range. Lake effect snow showers
will persist across the northwest Wisconsin snowbelt into Wednesday
before diminishing. A weak shortwave will pass near the Northland
Wednesday afternoon into Wednesday night and may lead to a few light
snow showers in The Arrowhead, but most of the Northland will remain
dry.

Upper ridging will then move overhead on Thursday allowing
temperatures to warm to near to above normal levels across the
region. This will result in highs in the upper teens and lower 20s
on Thursday before reaching the middle 20s to lower 30s for Friday
through Monday. Model solutions for the Friday-Saturday longwave
trough/upper low scenario with the GFS/Gem/ECMWF are coming closer
together in the upper levels, but significant differences remain in
regards to quantitative precipitation forecast. While there looks to be chances for light snow
Friday night into Saturday, considerable uncertainty still remains.
Guidance suggests a reinforcing shortwave will arrive during the day
on Saturday and this will give better chances for snowfall. Have
upped snow chances for Saturday in coordination with surrounding
offices to better capture this scenario.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1122 PM CST sun Dec 15 2019

A cold front and shortwave aloft will move through the Northland
tonight. These features have been producing MVFR ceilings and
areas of light snow or flurries. The visibility has dropped to 1
to 3 miles at times but was mostly 3 to 6+ miles. The light
snow/flurries will continue into the early morning hours but
decrease from west to east late tonight into Monday morning. MVFR
ceilings will also gradually lift and become scattered as well,
mainly after 12z and before 18z for most of Minnesota. It will
take longer for the MVFR ceilings to lift in northern Wisconsin,
but most areas are expected to see VFR conditions by late
afternoon. Ceilings will redevelop from west to east Monday
afternoon into Monday night, first low VFR then MVFR. There may be
more light snow or flurries as another shortwave and frontal
boundary take aim at the region Monday night.



&&

Marine...
issued at 404 am CST Mon Dec 16 2019

Breezy westerly winds will slowly diminish through the day today and
gradually back southwesterly tonight. Sustained winds of 10 to 20
knots with gusts to 25 to 30 knots this morning will diminish to 5
to 15 knots this afternoon with gusts to 20 knots. A cold front will
approach Western Lake Superior tonight and pass through during the
early morning hours. Winds will increase ahead of the front from the
southwest at 10 to 20 knots with gusts to 25 knots before becoming
northwesterly at 15 to 20 knots with gusts to 25 to 30 knots along
the Bayfield peninsula and in the Apostle Islands. Occasional gale-
force gusts to 35 knots will also be possible. This strong winds
will continue into the evening hours before diminishing overnight.
Additional small craft advisories will be needed for these winds
Tuesday morning into Tuesday night.

&&

Preliminary point temps/pops...
dlh 13 3 12 -14 / 10 20 10 0
inl 9 -2 5 -19 / 20 30 0 0
brd 15 6 15 -13 / 0 10 20 0
hyr 18 2 15 -13 / 10 20 20 0
asx 18 6 17 -5 / 20 30 30 20

&&

Dlh watches/warnings/advisories...
WI...none.
Minnesota...none.
Ls...Small Craft Advisory until 10 am CST this morning for lsz140-141-
146-147.

&&

$$

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