Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 151148

Area Forecast Discussion
National Weather Service Duluth MN
648 AM CDT SAT OCT 15 2016

.SHORT TERM...(Today through Sunday)
Issued at 424 AM CDT Sat Oct 15 2016

We have very warm conditions across the area this morning, with
temperatures pushing record warm minimum values so far this morning.
Synoptically we are in the warm sector ahead of a cold front.  A
surface low is over southern Manitoba, with the cold front extending
down into eastern North and South Dakota.  A warm front extends east
from the low into Ontario.  The southerly flow over Minnesota and
Wisconsin is keeping temperatures in the 50s and low 60s so far this
morning, about 20 degrees above normals for this time of year.  This
has also brought a lot of low level moisture and warm air advection
lift into the area.  It is not quite deep enough though, and cloud
bases remain above 1500 feet, and there has not been any fog or
drizzle development so far this morning.  Models depict this cold
front sweeping east across the forecast area during the day today,
and developing showers and even a few thunderstorms.  As little has
developed so far, most of them are overdoing the early morning
shower activity, but can buy into the late morning and afternoon
showers that develop across the eastern half of the forecast area
today and then drop southeast ahead of the tonight.  Have reduced
the early morning pops significantly and kept chance pops going for
the afternoon.  I have also boosted temperatures ahead of the front,
as it will not take much to warm up with as warm as we are this
morning, despite the cloud cover.  Tonight behind the cold front
temperatures should fall nicely in the evening as clouds clear from
west to east.  If it was just for this morning, we would set some
record warm min temperatures, except we are going to fall into the
40s to mid 50s by midnight tonight, setting our lows for today then
instead of this morning.  Depending on the amount of lingering
moisture, we may have some patchy fog tonight and have included it
in the forecast for now.  Most of Sunday should remain cool and dry,
with weak ridging moving east across the area.  However, our next
storm system begins to move towards the area late on Sunday with
some potential for showers and even a few thunderstorms as the front
pushes back into our area from the southwest during the afternoon.
With the low developing to our west some strong east flow is going
to develop over Lake Superior, bringing cooler marine air onto the
North Shore and into the Twin Ports, so have cooled off highs for
those areas.

.LONG TERM...(Sunday night through Friday)
Issued at 424 AM CDT Sat Oct 15 2016

Will initially see an occluded system sweep across central Canada
late Sunday through Monday. The lows associated cold and warm front
will slide through the Northland. Decided to a mention of
thunderstorms ahead of the trailing cold front as the latest GFS/NAM
show a few hundred J/kg of CAPE. Bumped up low temps heading into
Monday as southerly flow will advect 50-60 degree dewpoints into
southern portions of the CWA. Think the GFS is overdone bringing 50-
65 degree dewpoints to all of the Northland, but will need to keep
an eye on. If guidance trends towards the GFS, will need to increase
low temperatures heading into Monday further. Right now there are
some low 60s readings in the Hinckley area. The coolest readings are
in the Minnesota Arrowhead with temperatures in the 40s.

After good agreement between guidance through most of Monday, models
diverge on the intensity and timing of a low that develops across
northern Wisconsin. The ECWMF/GFS are more progressive with the
feature, while the NAM/GEM are slower. Still expect some shower and
thunderstorm chances as Monday night into Tuesday as the system
moves through. Highs on Monday will be mild with readings generally
in the 60s across Minnesota and Wisconsin, a few spots in northwest
Wisconsin will see highs around 70. Lows heading into Tuesday will
fall into the 40s.

Good agreement between ECWMF/GFS aloft Tuesday through Wednesday. A
shortwave will exit the region into Quebec by Tuesday evening. This
will keep the Upper Midwest in quasi-zonal flow behind the
shortwave, while a long wave trough digs into the Northern Plains.
The trough will continue to dig on Thursday, but the GFS is a bit
slower to bring this feature along. The differences between guidance
continue late in the week as the GFS cuts off a low in the Central
Plains, while the ECMWF over the central Great Lakes.

Will see cooler temperatures from Wednesday through Friday with
highs generally in the 40s and overnight lows in the 30s and low


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 648 AM CDT Sat Oct 15 2016

Will gradually see MVFR ceilings improve to VFR as a cold front
exits Minnesota. Will take a bit longer for ceilings to improve to
MVFR at KHYR, but expect VFR by 23Z. May see some showers and
perhaps a thunderstorm at KHYR later this afternoon, but uncertain
how widespread showers/storm so left as VCSH for the time being.
Expect gusty winds today, but will see winds lessen in comparison
to the overnight hours as the strong pressure gradient slides into
the central Great Lakes per the latest GFS/NAM/ECMWF.

Will see a 850 hPa ridge build into the region tonight. This will
bring clear skies and light winds. Expect patchy fog to develop
across northern Wisconsin, especially if precipitation falls this
afternoon. Left visibility at MVFR for the time being as uncertain
how low visibilities will get at this time.


DLH  65  44  58  51 /  20   0  10  70
INL  63  40  60  49 /  10   0  20  60
BRD  67  43  64  58 /  10   0  10  60
HYR  66  44  67  58 /  40   0   0  70
ASX  66  46  61  54 /  20   0   0  70


.DLH Watches/Warnings/Advisories...
LS...Small Craft Advisory until 10 AM CDT this morning for LSZ140.



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