Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 130553

Area Forecast Discussion
National Weather Service Duluth MN
1253 AM CDT Fri Oct 13 2017

Issued at 1250 AM CDT Fri Oct 13 2017

Updated aviation section below for 06Z TAF issuance.

UPDATE Issued at 931 PM CDT Thu Oct 12 2017

Upper wave depicted well in GOES-16 band 10 water vapor imagery
over eastern North Dakota and associated surface cold front
continue to approach the area this evening, with the surface front
likely entering the western part of the Duluth CWA within the
next hour or two. While the primary band of saturation trapped
below the inversion has translated eastward this evening, there
has finally been some redevelopment between the western fringe of
the stratus across NW Wisconsin and the approaching front. This
will likely lead to the development of isolated showers or areas
of drizzle over the next few hours, and persisting until frontal
passage. We have expanded low PoPs a bit in areal coverage through
much of the night.

Otherwise, the going forecast is in reasonable shape and the only
other changes were subtle adjustments to account for current
observational trends in cloud cover and temps.


.SHORT TERM...(This evening through Friday)
Issued at 318 PM CDT Thu Oct 12 2017

The forecast area was under the influence of a southerly flow ahead
of a cold front that was moving through the eastern Dakotas this
afternoon. A deck of stratus continues to affect the eastern two
thirds of the region thanks to this southerly flow. Some drizzle was
persisting up the north shore from low level convergence/uplift.
Expect the drizzle to diminish late for a brief period of time.

The cold front is progged to reach the western portion of the
forecast area by midnight. Some drizzle and showers are possible
along and ahead of the front where the deepest moisture is found.
This is in conjunction with some weak embedded pieces of energy moving
quickly in the southwest flow aloft. The cold front will progress
into the Arrowhead and northwest Wisconsin overnight. Showers or
drizzle will still be found ahead of the trof over the Arrowhead and
northwest Wisconsin, ending from West to East over northeast
Minnesota. The precipitation will get an assist from the arrival of
an upper level jet/divergence.

The cold front exits the Arrowhead in the morning, and the eastern
Wisconsin portion of the forecast area by noon. The precipitation
will end and high pressure will build across the region through the
day. The airmass will be drier and cooler. Max temps will be a few
degrees cooler than today.

.LONG TERM...(Friday night through Thursday)
Issued at 318 PM CDT Thu Oct 12 2017

Friday night should start off dry, but that doesn`t last long. A
deepening system approaches and cyclogenesis occurs over
Wisconsin. This will wrap a comma head of precip over the forecast
area. The precip will initially start as rain, but should
transition to a rain snow mix and be predominately snow north and
west of Duluth. Due to warm ground temperatures and the fairly
fast movement of the system, do not expect much in the way of
accumulations; however, the bulk of the frozen precipitation will
fall in the overnight hours (on Sunday morning) which may lend
towards more accumulation than forecast if surface temperatures
are cool enough.

Current QPF for the area is in the 0.25 to 0.75 inch range of
liquid equivalent which should translate into less than an inch or
two of snowfall accumulations mainly in the Arrowhead of
Minnesota and away from Lake Superior where the colder air mass is
located and not modified. The Wisconsin QPF totals will be towards
the higher end of that range, but should fall as rain.

Afterwards, high pressure builds for a return of dry weather and
warmer temperatures with highs near 60 through Thursday.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1250 AM CDT Fri Oct 13 2017

Cold front as of 06z is roughly on an axis from KINL to KBRD and
continues to progress steadily eastward. Ahead of the front, MVFR
ceilings have redeveloped across the Duluth and Hayward areas after
a few hours of clearing earlier this evening.  The cold front will
steadily progress eastward across all of the terminals overnight,
bringing a shift to westerly winds, and an erosion of the MVFR
ceilings from west to east.  VFR conditions are expected for Friday
as high pressure builds into the Northland.


DLH  47  55  37  53 /  20  10   0  70
INL  40  53  30  50 /  30   0   0  40
BRD  43  56  36  53 /  10   0   0  80
HYR  49  58  36  57 /  20  10   0  80
ASX  50  59  36  56 /  20  10   0  70


LS...Small Craft Advisory until 11 AM CDT this morning for LSZ140-141.



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