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FXUS63 KDLH 181130

Area Forecast Discussion
National Weather Service Duluth MN
630 AM CDT Wed Oct 18 2017

.SHORT TERM...(Today through Thursday)
Issued at 354 AM CDT Wed Oct 18 2017

The main concern for the short term involves the critical fire 
weather conditions over portions of central and north-central 
Minnesota this afternoon into this evening.

Early this morning a deep area of low pressure was centered over 
east-central Saskatchewan with a cool front extending south and 
west across northwest North Dakota and eastern Montana. A pre- 
frontal trough led the cool front and was found over central North
Dakota. South to southwesterly winds were found across the region
and skies were mainly clear over the Northland. An area of cirrus
ahead of the trough will spread eastward into north- central and 
central Minnesota this morning. Mainly sunny skies are expected 
after the initial cirrus moves through. GOES-16 imagery suggests 
the leading cirrus are thin with thicker clouds farther west. 
Temperatures will be warm today ahead of the front with readings 
topping out in the middle 60s to around 70 degrees from Brainerd 
northeast into the Arrowhead and over all of northwest Wisconsin. 
Temperatures will be a bit cooler over north- central Minnesota 
where the front will arrive first. The tightening pressure 
gradient over the region will result in strong westerly winds by 
early this afternoon. Sustained winds of 15 to 25 mph are expected
with wind gusts to 30 mph possible. The dry airmass in place will
be reinforced with drier air from the west. Forecast soundings 
suggest boundary layer mixing to nearly 800 mb is possible near 
International Falls, with the GFS mixing even deeper. The stronger
winds aloft should efficiently move moisture downwind resulting 
in very dry conditions over much of the Northland. The combination
of dry fuels, strong westerly winds, and minimum humidity values 
between 20 and 30 percent will result in critical fire weather 
conditions for portions of north- central Minnesota, and near-
critical conditions farther south and east. Winds will gradually 
subside this evening as the boundary layer decouples. Thursday 
will be quite dry once again, but wind speeds will be lower. Highs
will be in the middle 60s to near 70 degrees for most of the 
Northland. Temperatures will be near 60 degrees to the middle 60s 
in the Arrowhead.

.LONG TERM...(Thursday night through Tuesday)
Issued at 354 AM CDT Wed Oct 18 2017

Continued dry and warm under high pressure through Friday night.

A developing front fueled by an upper level trough slides through
the region on Sunday morning, but it will have difficulty fighting
through the strong ridge that has been anchored over the region.
Thus, precipitation may be greatly diminished compared to a more
progressive pattern. 

The next system arrives Monday as a strong jet pokes into the
region developing a surface low over western Ontario. Luckily the
system is still in the early stages of development, so it will 
act to cool the region back to seasonal temperatures and little if
any precip will develop though clouds should be prevalent.


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 628 AM CDT Wed Oct 18 2017

VFR, but contending with LLWS this morning as a cold, but dry
front moves into the region. Should be a fairly windy day with VFR
prevailing throughout the TAF period.


DLH  65  36  63  47 /   0   0   0   0 
INL  61  32  62  46 /   0   0   0   0 
BRD  64  36  66  49 /   0   0   0   0 
HYR  70  37  67  47 /   0   0   0   0 
ASX  71  39  67  47 /   0   0   0   0 


MN...Red Flag Warning from 1 PM this afternoon to 7 PM CDT this 
     evening for MNZ010-018.

LS...Small Craft Advisory from 10 AM this morning to 10 AM CDT 
     Thursday for LSZ140-141-146-147.

     Small Craft Advisory from 4 PM this afternoon to 4 AM CDT 
     Thursday for LSZ144-145.

     Small Craft Advisory from 10 AM this morning to 4 AM CDT 
     Thursday for LSZ121-142-143-148.


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