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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
630 am CDT Monday Oct 20 2014

issued at 630 am CDT Monday Oct 20 2014

Updated for the new 12z aviation discussion below.


Short term...(today through tuesday)
issued at 322 am CDT Monday Oct 20 2014

The main short term forecast issue revolves around cloud cover
through the period...and its affect on temperatures.

Northerly flow aloft is in place across the region this morning as
a trough swings east. A strengthening subsidence inversion will
occur today as surface high pressure moves in. A stratus deck
with bases from 1200-3500ft was occurring from Manitoba southeast
through The Arrowhead into the Upper Peninsula. Most of the models
show this cloud expanding south today and the stronger inversion
will make it tough to scour out the clouds. The models do suggest the
clouds will gradually break up...mainly over western areas...and
hold over the east. Where exactly the line of clearing sets up is
still in question. Low level flow will become more northeasterly
through the day into the evening and will make it tougher for areas
around Lake Superior clear out. We did increase cloud cover today
for most areas...then decreased it tonight. The exception tonight
will be around Lake Superior where a northeast/east flow will
occur and should allow for more cloudiness. In addition to the
cloud issues...there will be a tight thermal gradient across the
Northland with 850mb temperatures ranging from around +6c over our western -2c east. We have our warmest temperatures in the Brainerd
lakes region and coolest in The Arrowhead today.

There may be few showers today over eastern areas...mainly this
morning over The Arrowhead and this afternoon over our eastern
Wisconsin zones. Canadian radar shows some echoes headed
south/southeast toward The Arrowhead as of 0830z.

The high will move east of the area Tuesday allowing for an
increasing southeasterly flow. Clouds may hang tough for a time
around Lake Superior on Tuesday...but we think the increasing
southeast flow out of the dry high will be enough to cause the
clouds to diminish most areas Tuesday. Highs will range from the
middle fifties south and west to 45 to 50 from the twin ports into
The Arrowhead.

Long term...(tuesday night through sunday)
issued at 322 am CDT Monday Oct 20 2014

Surface high pressure will be over the central Great Lakes region
Tuesday evening. There will be a pronounced middle/upper level ridge
over the upper Midwest. Surface low pressure will be over the
northern High Plains...while a potent shortwave will be over the
northern Rocky Mountain states.

Southerly flow will increase Wednesday as the low pressure trough
moves into the plains. The trough will then move through the
Northland Wednesday night and Thursday. This low will bring warm and
humid flow into the upper Midwest. There will be increasing precipitation
chances from west to east Wednesday and Wednesday night. It appears
this system will bring widespread rains of about a tenth to quarter
inch of total rainfall to the Northland Wednesday into Thursday. The
precipitable waters values will be over 1 inch...which is pretty
substantial for this time of the year. There are some indications
that thunderstorms are possible. The nam12 and GFS are showing some
modest most unstable cape over the western forecast area Wednesday
afternoon and evening. At this time...think it is too early to add
storms to the forecast given the marginal of the indicators...but we
might need to add isolated thunder to subsequent forecasts.

Another middle/upper level ridge will move into the central United
States Friday. This will maintain the warm temperatures over the
Northland. Friday will likely be the warmest day of the week with
highs reaching the low 60s...about 10 to 15 degrees warmer than
normal. A cold front associated with a Canadian low pressure system
will move through the Northland Friday night. This will bring
slightly cooler weather for Saturday...but with highs still 5 to 10
degrees above normal.

Both the GFS and European model (ecmwf) are showing low pressure moving into the
plains during the latter half of the weekend and with a warm front
lifting into the Northland. The European model (ecmwf) and GFS are suggesting this
system could bring significant precipitation to the Northland.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 630 am CDT Monday Oct 20 2014

Cool northwest flow over the Northland today will bring a broken/overcast layer
of MVFR ceilings down from Canada. The MVFR will likely affect
kinl/khib/kdlh/khyr for periods this morning and early this
afternoon before lifting and/or scattering to VFR. It could make
it as far south as kbrd...but not confident enough to forecast the
MVFR that far south at this point.

Much of the region should return to VFR by the middle of the
afternoon. However...MVFR could linger at khyr through the rest of
the day. The kdlh and khib areas could see MVFR ceilings/visibilities return
late tonight.


Preliminary point temps/pops...
dlh 50 36 47 36 / 0 10 10 0
inl 48 32 55 37 / 0 0 0 0
brd 58 36 57 38 / 0 0 0 0
hyr 52 31 52 33 / 0 0 0 0
asx 49 36 50 33 / 10 10 10 0


Dlh watches/warnings/advisories...


Short term...melde
long term...grochocinski

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