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Area forecast discussion 
National Weather Service Duluth Minnesota
317 am CDT Wednesday Jul 23 2014

issued at 312 am CDT Wednesday Jul 23 2014

A quiet morning across the Northland as the region is under the
stable Post frontal regime with surface high pressure building in from
the northwest. Surface T/dew point spreads have lowered enough to promote some
patchy fog over sen County Warning Area and near kait. Additional areal coverage is
expected over the next several hours considering the forecast surface conditions
press deficits. Aloft a northwest flow remains anchored overhead as a middle
level ridge is amplifying over The Rockies. A few patches of cloud
cover are embedded within the deep layer northwest flow across The
Arrowhead and eastern wisc zones.


Short term...(today and tomorrow)
issued at 312 am CDT Wednesday Jul 23 2014

Today...surface high will dominate the region as middle level ridging
continues to provide deep layer subsidence. Light synoptic wind will
allow mesoscale forcing to dominate during the diurnal heating so we
should see a lake breeze in play today. This is indicated within the
higher res model output...especially the 3km dlh WRF. Xsects derived
from BUFKIT suggest a layer of scattered clouds are possible within the 5k
to 7k feet layer...possibly broken around midday/early afternoon over
eastern parts of the County Warning Area inland from Lake Superior. Maximum temperatures a few
degrees lower than yesterday based on lower 925 temperatures and lower
mixing layer depth.

Tonight...surface ridge axis will shift to eastern edge of the County Warning Area by early
morning. Maximum rad cooling potential will occur over eastern wisc zones
and arrowhead where clear and calm conditions develop.

Tomorrow...a warm advection pattern will spread east from the northern
plains into the upper Midwest. Although middle level ridging will remain
focused over the northern plains...models suggest a shortwave trough will
trek east from the Dakotas into Minnesota/Iowa by the late afternoon. A low level jet will
develop from eastern Nebraska into southwestern Minnesota underneath a middle level cap.
Convection should be favored across the eastern Dakotas by early afternoon
and shifting towards southwestern Minnesota by late in the day. Although most of
the precipitation should remain south of the area...a few storms may wander
into the brd lakes region.

Long term...(thursday night through tuesday)
issued at 312 am CDT Wednesday Jul 23 2014

Warm air advection and increasing moisture advection will lead to a chance for
showers and storms Thursday night into Friday as a weak disturbance
aloft moves through shortwave ridging. Stability will be marginal
across much of the Northland into Thursday night. The NAM increases
MUCAPE values to 1000j/kg by 12z Friday toward the Brainerd lakes
region...but the European model (ecmwf) only has around 400 j/kg. Stability will drop
further Friday as surface dewpoints climb into the lower to middle
sixties. The shortwave ridge will move over the Northland during the
day Friday...which should limit strength and coverage of the
showers/storms and low level convergence will be rather weak as
well. We will carry just low probability of precipitation for now.

The focus will then shift to a stronger upper low that will move
from southern sk Friday afternoon to northern Wisconsin by 12z
Sunday. Northerly flow aloft will then prevail into early next week.
There will be a chance for showers/storms as the upper low/trough
moves through...then it should dry out by Monday.

Expect highs from the middle to upper seventies Friday to warm a few
degrees Saturday. Highs will then drop to the lower to middle seventies
Sunday as colder air moves in on the northerly flow. Temperatures will
gradually warm through early next week.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1232 am CDT Wednesday Jul 23 2014

VFR conditions will prevail through the taf period as a high
pressure ridge settles over the area.


Preliminary point temps/pops...
dlh 76 50 76 58 / 0 0 0 30
inl 76 45 78 57 / 0 0 0 30
brd 79 55 79 63 / 0 10 20 40
hyr 77 45 79 59 / 0 0 10 20
asx 74 46 77 56 / 0 0 0 20


Dlh watches/warnings/advisories...


short term...Cannon
long term...melde

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