Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 252326

Area Forecast Discussion
National Weather Service Duluth MN
626 PM CDT THU AUG 25 2016

.SHORT TERM...(This evening through Friday)
Issued at 314 PM CDT Thu Aug 25 2016

A weakening upper low across northwest Ontario is resulting in cloud
cover and isolated showers across northeast Minnesota. In northwest
Wisconsin the day began sunny but high cirrus clouds are beginning
to spread into the area, the remains of thunderstorms last night
across parts of Kansas. Temperatures were cooler, with 850mb temp of
+9C at INL at 12z this morning, expected to fall a bit further
tonight as the upper low exits to the northeast and the coolest air
arrives in the wake of the low.

Tonight skies will clear out as cu dissipates in the evening. Fog is
expected to develop after midnight as winds become near-calm and
temperatures fall well below the "cross-over" temp used the popular
radiational fog forecasting technique. Lows in the mid 40s, except
near Lake Superior and larger inland lakes which will be warmer than
the air temp.

On Friday high pressure will build across the northern plains into
the mid to upper Mississippi river valley leading to mostly sunny
skies and cooler than normal temperatures. Some diurnally driven low-
topped cu is expected like is ongoing across the eastern Dakotas
today, but did knock the sky cover down a tiny bit from the previous
shift, focusing on where the low level moisture appears highest to
result in more cloud coverage. Highs Friday in the upper 60s to low

.LONG TERM...(Friday night through Thursday)
Issued at 314 PM CDT Thu Aug 25 2016

The extended period will be unsettled with several opportunities for
showers and storms.

A shortwave will move into the Northern Plains Friday night with
increasing warm air advection overnight. There will be a chance for
showers and a few thunderstorms overnight with a better chance
occurring Saturday into Saturday evening. Highs Saturday should be
in the upper sixties to around seventy.

As the shortwave moves off Saturday night, a broad upper ridge will
build over the northern CONUS into central Canada. We expect Sunday
to be mainly dry with temperatures rebounding into the seventies.
The GFS and ECMWF have come into a bit better agreement early next
week, there are some significant differences that remain though and
those amplify mid to late week. A weak front will move into the
Northland Monday then end up stalling and eventually returning
north. An area of low pressure will be over the Montana/Saskatchewan
region Monday, moving toward the Northern Plains Thursday. There
will be a chance for showers and thunderstorms Sunday night into
Monday as the frontal boundary moves through the region. After
Monday, confidence in the forecast diminishes as there is quite a
bit of uncertainty between the models as well as differences from
run to run within the same model. The bottom line will be the period
from Monday through Thursday will feature periodic chances for
showers and storms, some of which could be strong. Temperatures for
most areas will be above normal Sunday through Thursday.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 626 PM CDT Thu Aug 25 2016

A surface trof was moving through northeast MN at the start of the
forecast. It will move through northwest Wisconsin this evening.
This trof has been the focus for some scattered showers and a
large cumulus field. With the trof departure and the loss of
heating, expect the showers to end. With the cumulus field taking
on a flatter look, the clouds may linger longer than anticipated.
Latest short term model guidance has backed off on the fog for the
overnight. Have adjusted the prior fog forecast to just a TEMPO
mention. If fog does form, MVFR visibilities are expected.
Otherwise, VFR through the forecast.


DLH  48  70  55  69 /  10   0  20  50
INL  45  72  55  69 /  20   0  40  60
BRD  48  73  57  70 /   0  10  40  50
HYR  49  70  51  69 /  10   0  20  60
ASX  53  70  52  71 /  10  10  10  50


.DLH Watches/Warnings/Advisories...
LS...Small Craft Advisory until 10 PM CDT this evening for LSZ140-141-



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