Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 291438 AAA

Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
938 AM CDT Wed Mar 29 2017

Issued at 935 AM CDT Wed Mar 29 2017

Updated to include wording of much cooler temperatures near Lake
Superior. With brisk off-lake winds, temperatures will not rise
much beyond where they are currently at, in the mid 30s, today.


.SHORT TERM...(Today through Thursday)
Issued at 458 AM CDT Wed Mar 29 2017

Increasing cloud cover with cooler temperatures are expected
today across the Northland. A few showers may nose into our
southern Wisconsin zones tonight and Wednesday, with a wintry mix

Split flow will continue across the Upper Midwest today and
Thursday. Surface high pressure over northern Ontario and the
western Great Lakes this morning will shift farther eastward
today. A closed upper low will advance slowly eastward from the
Texas Panhandle this morning to the middle Mississippi Valley by
Thursday evening. Meanwhile a progressive, and weaker shortwave
trough will dig across the Canadian Prairies and Upper Midwest,
moving into northern Ontario by Thursday evening. Being between
these upper- level features will keep conditions fairly quiet
across the Northland during the period. Mid- and upper-level
stratus will spread across the area this morning and linger
through Thursday afternoon resulting in partly to mostly cloudy
skies across the area. Temperatures will trend a little cooler due
to the cloud cover. With the surface ridge shifting eastward, and
low pressure approaching from the west and southwest, winds will
be strong at the head of the lake and for portions of Iron and
Ashland Counties. The winds will be strongest along the North
Shore where the pressure gradient is expected to increase sharply.
Highs today will be in the middle 50s west to around 50 degrees
southeast, with upper 40s along the Lake Superior shore and in the

Skies may clear for central portions of the forecast area, while
overcast skies are favored southeast and portions of the
northwest. Temperatures will remain elevated overnight due to the
cloud cover with lows in the middle 20s to low 30s. Most models
bring a slight chance of showers into our southern Wisconsin
zones, generally south of Wisconsin State Highway 70 from Spooner
to Winter to Park Falls. Temperature profiles would suggest a mix
of rain, freezing rain, or snow. Do not expect noteworthy
accumulations of snow or ice as of this forecast package, but a
few secondary roads may be slippery for the Thursday morning
commute. The chance for precipitation shifts eastward during the
day and kept POPs limited to Price County after 12Z. Skies will
gradually clear across the north on Thursday as the northern
stream trough shifts east of the Northland. Temperatures will
climb into the low 50s west with 40s over the remainder of the

.LONG TERM...(Thursday night through Tuesday)
Issued at 458 AM CDT Wed Mar 29 2017

Latest guidance continues the trend of a fairly quiet long-term
forecast period. Thursday night/Friday morning looks to be dry
across most, if not all, of the Northland. A closed area of low
pressure is being progged to advance through the mid Mississippi
River Valley region during this time. The 29.00z GFS wants to
bring QPF as far north as Sawyer, Ashland, and Iron counties in NW
WI, but the CMC/NAM models keep this area dry. Consensus blends
continue the dry forecast that was inherited, so will keep this
trend going. Northeast flow due to the proximity of this low will
keep temperatures a bit cooler during the day Friday along Lake

A mid-level shortwave trough is then progged to dive southeast
across the region during the day Saturday, which looks to bring
chances of precipitation with it. However, there is some
uncertainty regarding the spatial extent of the precipitation as
the GFS/ECMWF/CMC models disagree on how far south precipitation
reaches. The GFS soundings show a brief period of deeper moisture
developing before drying above the 800 mb level. Consensus blends
have cut back on POPs quite a bit from the previous forecast,
which seems reasonable due to this uncertainty. Best chances look
to be along the International Border and Iron Range regions
through Saturday.

Sunday looks dry and very warm due to southerly return flow from
sfc high pressure. High temperatures Sunday look to reach into the
50s for all locations except for the tip of the MN Arrowhead.
Then, chances of precipitation linger from Monday morning through
Wednesday as another system makes its way into the region.
Uncertainty in the spatial extent does exist between the
GFS/CMC/ECWMF models at this time, so only kept chance POPs for
now. High temperatures in the upper 40s and into the 50s should
continue through the period.


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 626 AM CDT Wed Mar 29 2017

High cirrus clouds will continue to build into the region today,
with some SCT to BKN cloud decks possible. The band of stratus
that developed this morning near the head of Lake Superior
remained nearly stationary despite winds having a slight westerly
component. Not confident that it will propagate to the north over
the DLH TAF site. So, decided to remove the BKN008 TEMPO group
for DLH.

As an area of low pressure approaches the region from the south,
expect a low-level stratus deck to develop, with ceilings between
1 to 5 kft for all TAF sites except for INL. DLH and HIB are
expected to see MVFR cigs, while the other sites look to remain
VFR through the TAF period. Some MVFR fog looks to develop over
DLH tonight as well as a low-level inversion develops, which should
help to trap boundary layer moisture near the surface.


DLH  46  29  45  29 /   0   0   0   0
INL  53  30  51  29 /   0   0   0   0
BRD  54  31  51  30 /   0   0   0   0
HYR  51  32  47  28 /   0  10  10   0
ASX  48  28  44  28 /   0   0  10   0


LS...Small Craft Advisory until 10 PM CDT this evening for LSZ142>145.



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