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619
FXUS63 KDLH 192356
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
656 PM CDT Sat Aug 19 2017

.UPDATE...
Issued at 621 PM CDT Sat Aug 19 2017

Updated aviation section below for 00Z TAF TAF issuance.

&&

.SHORT TERM...(This evening through Sunday)
Issued at 325 PM CDT Sat Aug 19 2017

Concern for the short term is showers/thunderstorm chances
tonight/Sunday

For this evening...skies will be generally clear to partly cloudy
with light winds. A weak cold front will move southeast through
the forecast region late tonight and Sunday. With some decent lift
along the front and moisture, there could be a shower or an
isolated thunderstorm developing tonight across NE MN after
midnight. MUCAPES are in the 400-600 range tonight so the storms
should not be severe. The precipitation should end by sunrise
Sunday.

The front will move through NW WI Sunday afternoon. There will be
more instability due to heating with MUCAPES in the 1200-1400
range along with 25-30 knots deep layer shear. But, there will be
not as much moisture so as indicated by the previous forecast,
confidence for thunderstorm development is low due to a strong cap
over the region.

.LONG TERM...(Sunday night through Saturday)
Issued at 325 PM CDT Sat Aug 19 2017

Once the forecast cold front and upper trough moves away early in
the week, the extended outlook will be dry and warmer.

First, by Sunday night the upper low will be center north of Lake
Winnipeg with a series of vorticity centers rotating through the
trough. And this will bring a few brief showers over the
Northland.First, the cold front will be exiting northwestern
Wisconsin Sunday night with some instability ahead of the front with
MUCAPEs in the 1K to 2K range. by Monday afternoon another shortwave
will be rotating around the upper low and could bring a few show to
far northern MN. meanwhile on Monday a baroclinic zone will be
poised just to the south of the forecast area in northern Wisconsin
due to a surface low from KS to northern IL. This could also cause
some afternoon showers and thunderstorms across northwestern WI, but
much of Douglas and Bayfield County may be far enough north to
escape the the rain. A ridge of high pressure will bring dry weather
from Tuesday through Friday. A break down of the upper ridge may
help set off some showers in MN on Saturday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 656 PM CDT Sat Aug 19 2017

Scattered cumulus across the area this evening is expected to
diminish rapidly by 01z. A weak cold front will advance towards
the area after 09z tonight. Showers may accompany the front, so
have included some VCSH groups with VFR conditions. Fog is
possible ahead of the front with the lingering low level moisture
and light winds. Have included it for KHYR for now, but may need
to add it to other sites as well. Showers and a few thunderstorms
should redevelop after 18z, and while I have left it out of KHYR
for now, it may need to be added later.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  58  79  56  76 /  20  20  10  10
INL  60  77  49  75 /  40  10   0  20
BRD  61  78  54  76 /  30  10  10  10
HYR  57  81  56  79 /  10  30  10  20
ASX  59  85  57  78 /  10  20  10  10

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&

$$

UPDATE...LE
SHORT TERM...Stewart
LONG TERM...CLC
AVIATION...LE