Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 222320

Area Forecast Discussion
National Weather Service Duluth MN
620 PM CDT Tue Aug 22 2017

.SHORT TERM...(This evening through Wednesday)
Issued at 342 PM CDT Tue Aug 22 2017

A closed upper low over northeast Ontario is forecast to move
eastward into Quebec during the next 36 hours. Strong cyclonic
flow aloft and cool air advection will continue over the Upper
Midwest through the short term period. Scattered showers over the
Northland will diminish this evening with the loss of daytime
instability, but a few may be vigorous enough to produce a
lightning strike or two. Skies will clear tonight and winds will
diminish as the boundary layer decouples allowing for efficient
radiational cooling. Overnight lows will dip into the low 40s
north to the upper 40s south. A few of the climatologically cooler
locales could see temperatures in the middle 30s.

Cool cyclonic flow will continue across the Northland on
Wednesday. A potent shortwave trough over northern Saskatchewan
this afternoon had already begun to dive southward toward the
forecast area. Height falls ahead of that trough, and diurnal
heating, should be more than sufficient for showers to redevelop
during the late morning and early afternoon on Wednesday. A few
updrafts may be strong enough to become thunderstorms.
Temperatures will be cooler, however, with highs in the low 60s
northeast and over Iron County, WI and near 70 in central

.LONG TERM...(Wednesday night through Tuesday)
Issued at 342 PM CDT Tue Aug 22 2017

A weak shortwave will move through central Minnesota Wednesday
night. But with limited moisture, the showers will be widely
scattered mainly south of a Walker to Hayward line. A ridge builds
into the region on Thursday and keep the forecast area dry
through Friday morning. then a series of shortwaves will move
through the region and will be bring a chance for showers and
thunderstorms through the weekend. The second shortwave will be
associated with a slow moving area of low pressure that will pass
through southern Minnesota Saturday night through Sunday night.
Showers and thunderstorms will be likely across most of the
forecast area on Sunday. The precipitation will end by early
Monday morning as the low dissipates. There will be a break as a
ridge builds into the region with only showers along the
international border Tuesday night.


.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 620 PM CDT Tue Aug 22 2017

Showers will be in the vicinity of INL and HIB through the first
few hours of the forecast. This is in response to impulses
embedded in the northwest flow aloft. Showers will end shortly
after sunset with loss of diurnal heating. Gusty surface winds
will also diminish by sunset. A broken cumulus field is on tap for
Wednesday by 17Z due to diurnal heating and upper impulses passing
by. VFR is expected.


DLH  48  66  47  67 /   0  20  20   0
INL  43  67  39  70 /   0  10  10   0
BRD  47  69  48  69 /   0  30  30  10
HYR  47  67  44  69 /  10  10  20   0
ASX  49  67  45  68 /  20  10  10   0


LS...Small Craft Advisory until 10 PM CDT this evening for LSZ146-147.



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