Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 131223

Area Forecast Discussion
National Weather Service Duluth MN
623 AM CST Tue Feb 13 2018

Issued at 623 AM CST Tue Feb 13 2018

Snow has already ended in the Brainerd Lakes area. This trend will
continue through the morning. Have updated pops to end the snow
from west to east this morning. Rest of the forecast on track.

UPDATE Issued at 600 AM CST Tue Feb 13 2018

Please see the 12Z Aviation Discussion below.


.SHORT TERM...(Today through Wednesday)
Issued at 231 AM CST Tue Feb 13 2018

High pressure was located over the eastern Great Lakes at 0730Z with
ridging over the forecast area. The atmosphere remains very dry with
surface relative humidity less than 70 percent. This has kept any
snow from forming near the area. Plenty of mid and high clouds were
floating overhead and seen on radar. Even the activity on radar over
southern Minnesota was having difficulty reaching the ground. The
only observations with light snow/flurries was occurring gin east
central North Dakota, which was closest to the upper level trof
moving through the Dakotas. Short term models, as well as some of
the longer range models keep trying to initiate snow starting in the
Brainerd Lakes area early this morning. However, the drier air will
prevail for a bit longer before enough saturation occurs for any
snow to reach the ground. Have adjusted pops early this morning to
attempt to account for this trend. Models do indicate that the snow
will have moved away from the region by noon and have maintained
that approach. The upper level trof exits the region in the
afternoon allowing for drier air to return. A westerly flow becomes
established with warm air advection in play. With a clearing trend
in the afternoon, will see max temps warm into the 20s.

The upper flow is quasi-zonal tonight with dry air continuing to
cover the forecast area. Enough of a pressure gradient over the area
will keep wind speeds up. Neutral to weak warm air advection will
translate to warmer min temps tonight with teens common.

On Wednesday, an area of low pressure will move from Manitoba to
northwest Ontario. This will bring a cold front into northern
Minnesota late in the afternoon. Moisture is limited ahead of the
front and does not come into play until late. A dry day is expected
with some light precipitation possible over northwest Koochiching
county late, when some better moisture arrives. Warm air advection
continues Wednesday morning before colder air knocks on the door of
the Borderland late. Max temps should reach well into the 30s for
all locations before cooling late in the afternoon as the cold front

.LONG TERM...(Wednesday night through Monday)
Issued at 231 AM CST Tue Feb 13 2018

A positively tilted trough will dig from western Canada on Wednesday
evening southeastward into the Northern Plains by Thursday evening.
At the surface a cold front will slide southeastward into and
through the Northland. This will spread snow into the region from
northwest to southeast beginning Wednesday evening and eventually
coming to an end late Thursday night. Up to two inches of
accumulation across northern Minnesota, and the South Shore of Lake
Superior. Elsewhere totals will generally be less than one inch.
Expect the heaviest snowfall to occur Thursday morning.

Behind the cold front an arctic high will build into the region.
This will bring the next blast of arctic air and dangerously cold
wind chills into Friday morning. Lowered temperatures especially in
the typical cold spots across the forecast area as skies will become
mostly clear, which will allow for strong radiational cooling. Expect
the coldest readings of the extended Friday morning with lows
ranging from near zero along the Lake Superior Shoreline, to the
teens below zero in northern Minnesota. Wind chills of twenty to
thirty below zero are possible across much of northeast Minnesota
and portions of northwest Wisconsin. Skies will be partly to mostly
sunny on Friday with highs in the teens above zero across the

Temperatures will warm up over the weekend to near normal readings
as flow becomes quasi-zonal. This will bring highs in the 20s on
Saturday and Sunday, with lows ranging from the single digits above
zero to the teens above zero. Widespread precipitation chances
return for Sunday and Monday as a trough digs into the Northern
Plains from the Pacific Northwest. There are still large differences
in timing, strength, and location of this wave moving in. Due to
this have left chances of precipitation, but there is too much
spread between guidance for any specific details at this time. Stay
tuned for future updates.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 600 AM CST Tue Feb 13 2018

A shortwave trough will slide through the region early today. This
will bring IFR and MVFR conditions with light snow moving through
this morning. Expect this to quickly move through as shown by the
latest RAP/HRRR, which has had the best handle on the current
situation. In addition to snow, HIB/INL and BRD will see low level
wind shear due to the strong flow aloft and weak winds at the
surface this morning.

By mid morning all sites will see the mixed layer develop and tap
into strong flow aloft, which will bring gusty winds to all
terminals. By late in the morning and early afternoon, snow will
come to an end. Visibilities will improve and ceilings will
gradually scatter out to VFR. Gusty winds will subside Tuesday
evening as the mixed layer decouples.


DLH  24  15  35  17 /  50   0   0  20
INL  23  14  36   7 /  30   0  10  40
BRD  25  15  37  17 /  10   0   0  20
HYR  27  15  39  20 /  30   0   0  10
ASX  29  19  40  22 /  30   0   0  20




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