Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 232028

Area Forecast Discussion
National Weather Service Duluth MN
328 PM CDT Sun Oct 23 2016

.SHORT TERM...(This evening through Monday)
Issued at 323 PM CDT Sun Oct 23 2016

A surface low over southern Michigan this afternoon has left an
inverted trough extending west over northern Wisconsin, as well as
extensive cloud cover that extends over even farther west, over much
of northern and central Minnesota and eastern North Dakota. The
cloud cover is the main concern of the forecast, as most models show
it breaking up into fragments and diminishing despite the lack of
any real impetus to clear it in the northwest flow tonight.  There
is a small amount of cold air advection, but probably not enough to
cause widespread clearing with the main ridge staying to our west.
Models do advect a lot of the moisture off to the east, and the
clear slot over southern Manitoba favor the clearing trend, though.
For now have gone with a more pessimistic cloud trend.  The last two
nights the forecasts, both mine and the models have not been cold
enough, even under clouds. So, despite the extra cloud cover tonight
I have gone with colder than guidance min temperatures. I expect
that the holes that develop in the cloud cover should allow enough
radiational cooling to get to my forecast min temps. Monday the
cloud should finally clear out for most locations, though since
we`re not have a significant airmass change temperatures will
remain cool during the day with little mixing under the ridge to
help warm things up.

.LONG TERM...(Monday night through Sunday)
Issued at 323 PM CDT Sun Oct 23 2016

Summary: The Northland can expect near-seasonable weather through
most of this week, with highs generally in the middle to upper 40s.
There are still no signs for any significant snow, other than the
iffy chances of wet snow that would melt on impact if it even
happens, for the foreseeable future, but rain is likely for parts of
the Northland for the middle of the week.

A ridge of surface high pressure will stretch from northern Manitoba
through the western Great Lakes as of Monday evening, providing the
Northland mostly clear skies and very light easterly wind flow.
Tuesday morning low temperatures will likely be in the upper 20s and
lower 30s.

The high pressure will shift east Tuesday, and east-southeasterly
flow will develop. A wave is expected to lift out of the Southern
Rockies into the Central High Plains Monday night into Tuesday, and
it will develop an area of low pressure near eastern Colorado
Tuesday. The low will move east through the Central Plains Tuesday
and Tuesday night, then move into the southern Great Lakes Wednesday
into Wednesday night. The models have been indicating this low could
bring rain as far north as the Northland for late Tuesday night and
Wednesday as it moves through the Plains and Upper Midwest. However,
earlier questions about the low`s track, especially considering the
Canadian had a much farther north track than the GFS and ECMWF, may
have been put to rest due to much better model agreement with the
latest runs, providing higher confidence that a majority any rain
will likely be confined to the southern forecast area. The earlier,
more northern Canadian track threatened much more rain for the
Northland. The higher confidence in the track has allowed us to
increase pcpn chances across the southern forecast area and cut back
on some areas of the north. The rains will still face somewhat of a
challenge of lifting into the Northland because of the relatively
dry east-southeast flow. It will take some time to saturate the
lower levels for the rains to make any decent headway into our

Expect cloudier weather for Tuesday and Wednesday as the low moves
through the region, limiting highs to the middle to upper 40s. Even
if most of the rain remains across the southern forecast area, the
far northern forecast area could get some light rain associated with
synoptic lift ahead of another surface low and its trough moving
east through southern Canada. The models indicate some rain
associated with this feature will affect the Borderland and northern
Arrowhead late Wednesday into early Thursday.

The Northland should dry out Thursday, even if the cloud cover
lingers across the region. There is much less confidence in the
forecast beyond Thursday. There are big differences, still, between
the GFS and ECMWF. The GFS has one of our first significant Clipper
Systems passing through southern Canada Friday, bringing some rain
and maybe rain/snow mix to the far northern Minnesota, followed by a
dose of substantially colder air Friday night and Saturday.
Northwest Ontario could get significant accumulating snow, but this
track suggests that snow would remain safely north of the Minnesota
border. On the other hand, the ECMWF only hints at a weak Clipper
System, barely registrable as an area of low pressure, passing
through southern Canada much later in the day Friday and into Friday
night. The weaker low does not draw down cold air anything like the
GFS Clipper does. For now, leaned on a blend and hope to get some
better confidence in the late part of the week`s forecast once the
Canadian comes into range of this time period.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1258 PM CDT Sun Oct 23 2016

Widespread broken/overcast MVFR to lower-end VFR ceilings were
found across northeast Minnesota and northwest Wisconsin as cooler
air flowed into the region in the wake of a passing area of low
pressure. Expect a gradual transition to more VFR ceilings, but
MVFR could linger into this evening, especially across far
northern Minnesota. There may be some clearing tonight as high
pressure builds into the region from the west, but MVFR ceilings
could linger or move back into the KINL and KHIB areas overnight
and linger Monday morning.


DLH  32  48  34  46 /   0   0   0  10
INL  32  45  31  47 /  10   0   0   0
BRD  32  50  36  50 /   0   0   0  30
HYR  33  51  31  50 /   0   0   0  10
ASX  37  49  34  48 /  10   0   0   0


LS...Small Craft Advisory until 4 PM CDT this afternoon for LSZ121-



LONG TERM...Grochocinski
AVIATION...Grochocinski is the U.S. government's official web portal to all federal, state and local government web resources and services.