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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
641 am CDT Wednesday Jul 30 2014

Short term...(today and tonight)
issued at 335 am CDT Wednesday Jul 30 2014

Main concerns in the short term remained focused around the areas
of fog this morning...locally dense at times...and the potential
for scattered rain showers and isolated thunderstorms this
afternoon and into the evening across the eastern half of the forecast
area.

The cool and active nearly pattern will persist today and tonight
as a deep upper trough over eastern Canada continues to rotate very
slowly eastward. Showers and storms triggered yesterday
afternoon/evening have since diminished and moved out of the area.
However...the rain has leftover a very moist near-surface layer that
is combining with clearing skies...cooling temperatures and light
winds to produce areas of fog this morning. Visibilities will drop
to 1/2 to 1/4 mile at times. A dense fog advisory may be needed
for a few hours...but will hold off at this time and monitor the
trends in the next couple hours. Conditions will continue to
remain favorable for fog through the middle morning...before the high
sun angle and dry air aloft begin to mix the bl enough to scour
the fog and low clouds out.

Much of the Northland will be caught between the active...cool
cyclonic flow to the east and a building Dry Ridge of high
pressure to the west. Plenty of sun through the late morning and
early afternoon will allow temperatures to warm into the middle to
upper 70s...with a few lower 80s possible. The rise in
temperatures and destabilizing bndy layer will combine with an
embedded short wave dropping in from the north to produce middle- late
afternoon convection from The Arrowhead southward through the twin ports
and into northwest WI. Ml cape values increase to around 500 j/kg and
deep layer shear remains favorable for another round of possibly
strong T-storms with small hail and strong winds. Cannot rule out
an isolated severe storm as well.

Convection will be largely forced by the diurnal heating today...so
expect much of the showers and storms to diminish in coverage and
intensity after sunset with skies clearing out after midnight.
Temperatures tonight will fall into the upper 40s and lower 50s
again.

Long term...(thursday through tuesday)
issued at 335 am CDT Wednesday Jul 30 2014

Looking at the big picture....the upper low over James Bay Canada
slips south and then east into the weekend...followed by upper level
ridging over the western Great Lakes region.

This upper low will continue the trend of bring S/waves south into northern
MN/WI...and setting off afternoon storms through Thursday. Long
range models suggest the low finally begins to fill and very slowly
push east Friday...with a brief period of ridging Saturday and
Saturday night. However this will be short-lived as a series of
S/waves ride over the ridge. On Sunday both the GFS and European model (ecmwf) point
at a low pressure developing in the high plain and setting up a warm
front over central Minnesota and northern WI...this could mean a cloudy and wet
beginning of the week over the forecast area. The GFS keeps the front nearly
stationary while the European model (ecmwf) is more progressive with this system. At
any rate...there will be chances of showers and thunderstorms
throughout next week.

&&

Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 639 am CDT Wednesday Jul 30 2014

Dense fog over the area will quickly dissipate after 12z...with fvr
conditons the rest of the daylight hours. Thunderstorms will again
popup acorss northeastern Minnesota and northwestern WI this afternoon and
continue until about 02z...then a bit more fog may form overnight.
Kinl and kbrd are not expected to recieve any thunderstorms.

&&

Preliminary point temps/pops...
dlh 78 55 79 54 / 30 20 20 10
inl 80 52 79 51 / 10 10 20 10
brd 80 56 82 56 / 10 10 20 10
hyr 77 51 81 53 / 30 30 30 20
asx 77 52 74 52 / 30 20 20 10

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...none.
&&

$$

Short term...bjt
long term...clc
aviation...clc

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