Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 271751

Area Forecast Discussion
National Weather Service Duluth MN
1251 PM CDT Mon Mar 27 2017

Issued at 1239 PM CDT Mon Mar 27 2017

Updated aviation section below.


.SHORT TERM...(Today through Tuesday)
Issued at 358 AM CDT Mon Mar 27 2017

A few areas of wintry mixed precipitation are expected this
morning before high pressure builds for the afternoon, yielding
dry and partly cloudy conditions through Tuesday.

Mainly cloudy skies were found across much of the Northland at
330 AM this morning. Areas of fog have been reported, with some
locales experiencing patchy dense fog. A few rain showers were
found across the southern portion of our Wisconsin zones, mainly
south of a line from Spooner to New Post, to Park Falls. Another
area of radar echoes was observed over central and portions of
north-central Minnesota, but precipitation was not reaching the
ground. Temperatures were at or a few degrees above freezing in
northwest Wisconsin, to the upper 20s to low 30s in northeast

A weak cool front arced from southeast Saskatchewan across
northern North Dakota and northern Minnesota into northern Ontario
this morning with a ridge of high pressure over the Canadian
Prairies. A trough of low pressure aloft was over the central
Dakotas, with a smaller shortwave trough was over northeast
Minnesota. Two ribbons of cyclonic vorticity marked the eastern
edges of both troughs. Forcing for ascent with the leading trough
was supporting the showers over northwest Wisconsin, while the
trailing and deeper trough blossoming the radar returns in central
and northern Minnesota. A low-level wedge of dry air on the INL,
MPX, and ABR 27.00Z soundings suggests those echoes will need to
intensify before saturating the column enough to reach the
surface. Have added some low chance POPs from the Brainerd Lakes
into the Arrowhead this morning as the precipitation processes
aloft continue and lift northeastward. The showers over northwest
Wisconsin are expected to drift east-southeast with time and
should exit the forecast area later this morning or early this
afternoon. Thermal profiles over Minnesota suggest a possibility
for light snow or rain showers, while rain or freezing rain is
favored in northwest Wisconsin. Any areas which receive freezing
rain this morning can expect only a thin glaze, which will melt
quickly after sunrise. The cool front will sag southeastward today
before virtually washing out by early evening. Nudged temps a
little warmer today, especially in the western zones, but still
cooler than consensus. Think the lingering cloud cover will be
slow to erode this morning and early afternoon, limiting diurnal

Partly cloudy to mainly clear skies are expected for tonight as
high pressure drifts overhead. With recent mild temperatures,
precipitation, and some melting snowpack, think fog and low
stratus will develop tonight, especially in north-central
Minnesota and north of the Iron Range. However, the light winds
and mainly clear skies early should be sufficient to cool much of
our Minnesota zones below the consensus blends before fog
develops. Have nudged the overnight lows cooler as a result. High
pressure will remain in control on Tuesday yielding mainly sunny
to partly cloudy skies. Temperatures should climb a few degrees
warmer, except near Lake Superior where onshore flow will work to
keep highs in the upper 30s to low 40s.

.LONG TERM...(Tuesday night through Sunday)
Issued at 358 AM CDT Mon Mar 27 2017

Upper level and surface ridging will cover the forecast area
Tuesday night through Wednesday. The surface ridge remains on
Wednesday while a baggy shortwave approaches from the west. This
baggy shortwave in the northern stream begins to phase with the
southern streams closed low moving through the Central Plains
Wednesday night. Differences begin to show up in the handling of
this melange, especially in regard to QPF. The ECMWF is more
bullish with QPF into north-central Wisconsin by 12Z Thursday.
Leaned to the drier approach of the GFS/GEM and have a dry
forecast Wednesday night. Thursday and Thursday night finds the
northern stream disconnecting from the southern stream on the GFS
which keeps a dry forecast/surface ridging over the region. The
GEM/ECMWF maintain the phasing until late Thursday night. Used a
blend which favored the GEM/ECMWF which had QPF tracks across the
southeast portion of the Wisconsin forecast area Thursday and
Thursday evening, before the system departs late. A surface high
drifts over the region Friday with weak upper ridging. The models
come into better agreement with the handling of the mass fields
Friday night and Saturday. An upper-level shortwave trough
crosses the forecast area late Friday night through Saturday. A
cold front will sweep across the region. Thermal profiles suggest
a rain/snow mix late Friday night changing to all rain Saturday.
Model differences return for Saturday night and Sunday. The GEM
has a clipper moving over the region, while the GFS/ECMWF feature
surface high pressure nearby, but large differences aloft. The GEM
was ignored. Used a blended approach which resulted in some low
chance POPs with the rain/snow mix in the evening, snow late,
then back to rain during the day Sunday with just enough upper
forcing nearby to warrant a mention.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1239 PM CDT Mon Mar 27 2017

VFR conditions as of issuance time, with a weak cold front just
south of the terminals and a ridge of high pressure building in
from the north. This ridge will continue to slide into the area
over the next 24 hours. Fog and some stratus are expected to
develop for KINL, KHIB and KDLH overnight tonight, with
MVFR visibilities developing between 03z-05z, and lowering to IFR
for some locations around 09z, and then improving back to VFR by
16z. Stratus may accompany the fog for KINL. Light winds less than
6 knots expected through the TAF period.


DLH  46  28  47  28 /  10   0   0   0
INL  45  24  48  27 /   0   0   0   0
BRD  56  29  57  31 /  10   0   0   0
HYR  47  27  54  27 /  10   0   0   0
ASX  44  27  45  27 /  10   0   0   0




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