Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46
FXUS63 KDLH 271739

Area Forecast Discussion
National Weather Service Duluth MN
1239 PM CDT TUE SEP 27 2016

Issued at 1239 PM CDT Tue Sep 27 2016

Updated for the new 18Z Aviation Discussion below.


.SHORT TERM...(Today through Wednesday)
Issued at 321 AM CDT Tue Sep 27 2016

At 315 AM, skies ranged from mostly clear in the southwest corner
of the CWA to mostly cloudy elsewhere. Temperatures were largely
in the 40s north and lower 50s south. Rain showers continued to
move southeastward across the CWA, especially the northeast half
of the area.

The focus for today through Wednesday will be the continued
potential for rain showers across the CWA. The models generally
push moisture further west and south with time today, resulting
in an increasing chance of showers across the remainder of the
area as the morning wears on. Will continue to mention fairly high
pops across most areas today. While the QPF will not be
particularly high, it is shaping up to be a high POP/low QPF kind
of a day. Gusty northwest winds will continue today, reaching near
30 MPH at times.

The showers will continue tonight, although there should be a
gradual decrease in precipitation most areas. By 12Z Wednesday,
showers will largely be confined to the eastern portion of the
region, with drier air being advected into northeast Minnesota.

Some showers will linger downwind of Lake Superior on Wednesday,
while clouds break up across the majority of the region. Gusty
north winds will continue, especially in Wisconsin, while winds
generally decrease across the rest of the region during the day.
High temperatures will climb back into the 60s on Wednesday.

.LONG TERM...(Wednesday night through Monday)
Issued at 321 AM CDT Tue Sep 27 2016

Seasonable to mild temperatures under sunny skies late this week
through the weekend, with increasing clouds and a chance for showers
early next week.

On the synoptic scale the stubborn upper low across the upper Great
Lakes through mid-week will slowly move towards the Ohio valley
later this week, then retrograde to the northwest to some degree
over the weekend. There remains some uncertainty to the track of the
upper low into the weekend, with the ECMWF continuing to be
persistent on solution that brings the upper low back up to the
upper Great Lakes over the weekend and could result in more cloud
cover than currently anticipated Saturday and Sunday. GFS/GEFS/GEM-
Global have slightly trended towards the ECMWF, but depict more
progressive solutions where the upper low exits towards New England
by the end of the weekend. Regardless of the upper low track, warmer
weather is on the way as sunny skies and warmer air aloft results in
mild temperatures through the long term period with highs in the 60s
- around ten degrees above normal in some locations.

Late in the weekend into early next week, southerly to southwest
flow develops aloft in response to a broad mid-level trough across
the west coast with several embedded shortwave troughs rotating
around it. The first of these mid-level shortwave troughs will eject
into the central/northern high Plains Monday resulting in an area of
low pressure developing in the western Dakotas to southern Manitoba
and an associated warm front lifting north and east across the
northern Plains. This warm front will approach the upper Midwest
Monday leading to increasing chances for showers and perhaps a few
thunderstorms. Chances for showers and storms appear best Tuesday
into Wednesday when the broad longwave trough ejects across the
Rockies and into the Plains. The exact evolution of this pattern
varies run-to-run and model-to-model, but in general it looks like
most solutions would favor an active work week for the first full
week of October.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1239 PM CDT Tue Sep 27 2016

A large area of low pressure over eastern Lake Superior is
resulting in cool northwest flow, widespread MVFR ceilings, and
light rain across northeast Minnesota and northwest Wisconsin, as
of early this afternoon. The low will move south through the Great
Lakes region, which will shift the current light rain to the south
and east by later today. However, the low ceilings are expected to
linger into Wednesday morning, at times becoming IFR this evening
and overnight.

High pressure will begin to shift into the region Wednesday,
helping to clear out the region. There could be a period of MVFR
ceilings late Wednesday morning and early afternoon from
widespread broken cumulus clouds until better lifting and clearing
of the clouds occurs later in the afternoon.

There could be a brief period of significant low-level wind shear
at KHYR late tonight, shortly before and around dawn. The hourly
RAP model is indicating an impulse of stronger north-northeast
flow aloft, nearly 35 knots, could pass through the KHYR area over
a 3-hour window. May need to add LLWS with subsequent forecasts.


DLH  52  46  60  43 /  70  30   0   0
INL  50  40  61  42 /  60  20   0   0
BRD  54  42  62  42 /  40  30   0   0
HYR  50  48  61  43 /  80  40  20  10
ASX  55  49  60  47 /  80  60  30  10


.DLH Watches/Warnings/Advisories...
LS...Small Craft Advisory until 4 PM CDT Wednesday for LSZ146-147.

     Small Craft Advisory from 4 AM to 4 PM CDT Wednesday for LSZ144-

     Small Craft Advisory from 10 PM this evening to 4 PM CDT
     Wednesday for LSZ140>143.

     Small Craft Advisory until 10 PM CDT Wednesday for LSZ121-148.



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