Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 261802
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1202 PM CST Sat Nov 26 2016

.SHORT TERM...(Today through Sunday)
Issued at 315 AM CST Sat Nov 26 2016

A strong inversion will lock the fairly widespread stratus deck
across the Northland through the rest of the weekend. Temperatures
will be on the mild side, though some minor adjustments have been
made to account for the more pessimistic cloud cover anticipated.
Warmer Sunday due to warm air advection ahead of the low pressure
system approaching from the southwest, with the warmer air moving
across the snow pack tonight likely leading to fog developing.

On the synoptic scale a mid-level ridge axis will move from west to
east across northwest Ontario with a weak warm front moving in from
the west over the upper Midwest. While some mid/high level clouds
will move across the region today associated with the warm front, a
strong low level inversion will trap the stratus deck prevalent
across northeast Minnesota and northwest Wisconsin this morning.
While surface heating may allow for some breaks in the stratus this
afternoon, any breaks in the clouds would likely be filled by
stratocu. Guidance has trended towards any breaks in the clouds
being fairly limited, though on fog channel satellite imagery and
surface obs this morning several pockets of clearing are noted, so
the guidance may be a bit too aggressive with the stratus deck.
Still, more clouds than sun today will lead to highs limited to the
mid 30s similar to Friday. Early RAP runs depict highs even cooler
in the low 30s where the stratus deck will likely stick and near 40
across inland NW Wisconsin where clearing is more likely, so some
adjustments may be necessary in a further update. Light south winds
through the day at around 5-10mph.

Tonight stratus will persist with fog likely across much of the
region due to warm southerly wind moving in across a decent
snowpack. NOHRSC analysis and co-op observations indicate a decent
4"+ snow pack across northeast Minnesota with some pockets of lesser
snow depths across parts of northwest Wisconsin such as the Hayward
lakes region. Still, with the southerly winds fog should be fairly
widespread. SREF and other short-term guidance is fairly aggressive
on coverage and intensity of fog, so felt confident introducing
areas/widespread fog wording in the forecast. Lows in the mid to
upper 20s.

Warmer Sunday with continued cloud cover. Southwest winds increasing
to 10 to 15 mph. Highs ranging from the mid 30s in northeast
Minnesota to low to mid 40s in northwest Wisconsin.

.LONG TERM...(Sunday night through Friday)
Issued at 315 AM CST Sat Nov 26 2016

The main story for the long-term looks to be a broad mid-level
shortwave trough that develops out of the Four Corners region that
is progged to translate to the northeast across NE and SD. A strong
165+ kt 250 mb jet streak develops in association with this
shortwave, which places the Upper Midwest in the left exit region of
the jet, in an area of enhanced divergence aloft. An upper-level cut-
off low develops, which results in a nearly stationary sfc low
pressure across the region, sticking around from Monday through the
day Thursday. Southerly flow and warm air advection in the low
levels look to increase during the day Monday, with GFS 925 mb
temperatures warming into the 5-10 degree C range. These values look
to be a bit too warm as the NAM/ECMWF models are going with values
more between 0-5 degrees C. Still, the thermal profiles suggest
precipitation on Monday to start as rain. The models are hinting at
some elevated instability Monday afternoon as well, with values of
elevated convective available potential energy between 50-100 J/kg
in the NAM and GFS model soundings. So, I kept a slight chance of
thunderstorms Monday afternoon. Then, the general thermal profile
cools, which suggests a transition to a wintry mix Monday evening
into Tuesday morning. Chances of precipitation look to continue
through Friday as the low pressure system very slowly moves to the
east during this time period. Expect skies to be mostly cloudy
otherwise. High temperatures look to stay above normal Monday
through Wednesday before temps drop to more normal levels Thursday
as cold air advection behind the low pressure system moves in. Highs
Monday through Wednesday look to be in the mid to upper 40s Monday
into the mid to upper 30s Tuesday and Wednesday. Winds look to also
intensify due to a tightening sfc pressure gradient associated with
this sfc low on Monday as southeast gusts between 20-25 kts are
expected.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1157 AM CST Sat Nov 26 2016

Low clouds continued to blanket much of the Northland, with CIG`s
and VSBY`s in the IFR/LIFR range in some areas. We were also
seeing some breaks in the low clouds due to some diurnal heating
and mixing out in portions of north central Minnesota and portions
of northwest Wisconsin. We will likely continue to see these areas
of clearing, with the low clouds hanging on the longest in the
KBRD area due to thicker clouds in that area. KINL and KHYR have
the best chance of seeing VFR conditions today. As night falls, we
should see a proliferation of fog and low clouds once again.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  35  28  38  36 /   0   0  10  80
INL  35  27  36  33 /   0   0   0  70
BRD  36  27  38  37 /   0   0  10  80
HYR  38  29  42  38 /   0   0   0  80
ASX  39  30  42  38 /   0   0   0  80

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&

$$

SHORT TERM...JJM
LONG TERM...JTS
AVIATION...DAP



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