Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 230845

Area Forecast Discussion
National Weather Service Duluth MN
345 AM CDT Wed Aug 23 2017

.SHORT TERM...(Today through Thursday)
Issued at 345 AM CDT Wed Aug 23 2017

Winds have weakened quite a bit this early morning as the sfc
pressure gradient has slackened. A weak trough of low pressure
currently located over the Minnesota Arrowhead has supported some
scattered to broken cloud cover over northeast Minnesota, with
some very weak radar echoes observed just north of Taconite
Harbor. This activity is not expected to amount to much, if any,
precipitation. The better chances of precipitation this morning
will be downstream of Lake Superior over Iron, Ashland, and Price
counties in northwest Wisconsin. Again, not much in the way of
precipitation expected with any showers that develop in that area.

The better chances of precipitation will arrive over north-central
and east-central Minnesota this afternoon and evening as a mid-
level shortwave trough dives southeastward through the region from
central Saskatchewan Canada. This shortwave looks to bring with
it deeper lift, as evidenced by enhanced mid-level isentropic
lift, and upper-level divergence. However, a limiting factor for
precipitation amounts with this wave will be deeper moisture, per
the latest RAP and NAM soundings. Instability is severely lacking
with this system, as only the Canadian model is indicating any
appreciable MUCAPE. For now, will leave any notable thunderstorm
mentions out of the forecast, but a rumble of thunder can`t be
ruled out later today. Highs today will range from the lower 60s
over the Minnesota Arrowhead to the middle to upper 60s further

As the shortwave departs the region, skies will clear from north to
south. This, coupled with another night of light winds, should lead
to another night of good radiational cooling. This will also lead to
the potential for fog over the Northland, but much will depend on
how quickly clouds associated with the departing shortwave moves
out. If they linger longer than expected, then this will preclude
any fog. The better potential for fog will be over the
International Border area as they will see clearing skies sooner
than across the south. Lows Wednesday night/Thursday morning will
be on the chilly side, with upper 30s over the north to the lower
to middle 40s south. High pressure then builds into the region
for Thursday, leading to mostly sunny skies. Highs will still be slightly
below seasonal normal, with temperatures in the middle to upper

.LONG TERM...(Thursday night through Tuesday)
Issued at 339 AM CDT Wed Aug 23 2017

The extended period will start out dry as high pressure is off to
the east of the Northland with east to southeast low level flow. It
will be cool Thursday night with lows from the upper thirties in
parts of the Arrowhead to around fifty in the Brainerd Lakes region.

A series of weaker shortwaves will break down the upper ridge
causing a trough to form over the region over the weekend into early
next week. There will be increasing moisture over the Northland as
well as persistent southerly low level flow develops and continues
into early next week. There will be a chance for showers over far
southern portions of the Northland Friday with chances increasing
and spreading north Friday night into Saturday and increasing
further Saturday night into Sunday as a stronger shortwave arrives.
Showers will be most widespread Saturday night into Sunday. Highs
Friday will be in the upper sixties to lower seventies with mainly
sixties Saturday and Sunday. Off lake winds will be on the increase
Friday, continuing into the weekend with low pressure developing off
to the west Friday then tracking across the Northland through the

The chance for rain will diminish Monday as the trough shifts east
and northwest flow aloft redevelops. There will be another chance
for showers and a few thunderstorms Tuesday over parts of the
Northland as a shortwave moves through/near the region. Highs will
be warmer Tuesday, mostly from 70 to 75.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1237 AM CDT Wed Aug 23 2017

VFR through the forecast. An upper level short wave trof will drop
through Canada to near the international border by 00Z Thursday,
and into the region by 03Z. This will keep some clouds around
through the forecast. Some showers will form during this time, but
exact timing is difficult this far out and have VCSH mention at
BRD starting at 02Z.


DLH  66  46  67  47 /  10  10   0   0
INL  65  38  70  41 /  10  10   0   0
BRD  70  48  68  52 /  30  50  10  10
HYR  67  43  69  43 /  10  20  10  10
ASX  67  43  68  44 /  10  10   0   0




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