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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
1037 am CDT Wednesday Oct 22 2014

issued at 1022 am CDT Wednesday Oct 22 2014

Band of altocumulus castellanus evident on Sat imagery from just south of kpwc to
southern part of state...advecting east. Rap13 shows this are aligned
well with 850 mb dewpoint axis of 8c/10c. 88d kmpx shows a line of
convection associated with this feature earlier this morning has
diminished. No lightning strikes at this time and a sprinkle or two has occured
within this cloud band. Latest forecast rap13 and hrrr sim reflectivity
product indicates a few sprinkles may occur with this area as it
translates east today. 850 mb 10c dewpoint axis does extend rapidly
north to include all of western County Warning Area by 18z...and western/ctrl County Warning Area by 21z.
Forecast unstable low/middle level lapse rates remain south of County Warning Area today so
have removed thunder mention with some slight intrepidation.
Otherwise adjusted maximum temperatures a degree or two higher based on
morning 925 temps/advection....and increased gusts based on values
already in excess of 25 miles per hour in western County Warning Area. Otherwise main precipitation
event still forecast to sweep over area tonight/early Thursday morning.


Short term...(today and tonight)
issued at 405 am CDT Wednesday Oct 22 2014

Main concerns in the short term are focused around the cold front
expected to move across the region later today and tonight with
rain showers and possibly a few weak isolated T-storms over NE
Minnesota...mainly this afternoon/early evening. Widespread rain will
likely persist across the Northland most of tonight and early Thursday
morning. Will also highlight the gusty S/southeast winds this afternoon
ahead of the front...with slightly warmer temperatures today and
even warmer conditions on Thursday.

Upper ridge extending from the middle MS valley region north/northeastward into
northern Quebec this morning is being squeezed by a cutoff low over the
middle-Atlantic region and the next incoming short wave rolling in across
the northern Front Range of The Rockies. At the surface an inverted ridge
from eastern Quebec extending back into the western Ohio Valley region is
dragging eastward slowly across the Great Lakes...and allowing the next
system moving in from the west to increase the pressure gradient over
the upper Midwest. A strengthening pressure gradient today combined
with bl mixing will produce sustained S/southeast winds around 10 to 15
miles per hour...and gusts up to or exceeding 20 miles per hour this afternoon. The air
mass preceding the frontal passage will attempt to become unstable with
MLCAPE values around 100 j/kg and steepening lapse rates in the
afternoon. Increasing moisture on the nose of modest moisture
transport from the south will allow conditions to become favorable
for a few weak storms late this afternoon and early evening.

As the upper trough approaches tonight...the broad large scale
lift and deep layer shear will become more favorable to support
more organized showers. However the instability will really fall
off and hinder any potential for thunder. So...will continue with
likely rain showers tonight along the front with conditions drying
out quickly behind the front Thursday morning. Could see a few showers
linger around Lake Superior Thursday afternoon. Otherwise...high
pressure with ridging aloft begins to take hold later in the day

Temperatures today will warm into upper 40s and lower 50s across
The Arrowhead...and into the middle to upper 50s over areas to the
west and south. This will be a few degrees warmer than Tuesday for
most areas. Cloudy skies will keep temperatures mild tonight...only
falling into the 40s. On Thursday...skies will clear to the west
and allow temperatures to rise into the upper 50s and lower 60s. Areas to
the east will rise another couple degrees into the lower to middle

Long term...(thursday through tuesday)
issued at 405 am CDT Wednesday Oct 22 2014

A series of fast moving short waves will translate across the
Northland through the extended period. A vorticity maximum will bring
increasing clouds Friday...mainly to the eastern half of the County Warning Area.
However...the dry air mas is expected to limit any precipitation. A
more organized wave will drop over the Lake Superior region
Saturday...but at this time the main area of precipitation is
expected to remain to the east of the County Warning Area. Small probability of precipitation may be needed
in the tip of the Minnesota arrowhead Sat if the track of the low trends
any further west. Long range models are in good agreement that a 850 mb
ridge axis moves into western Minnesota Saturday afternoon...gradually shifting
east over Wisconsin Sunday...keeping the Northland dry and mostly
sunny through the weekend. The exception may be some low
clouds/drizzle that may develop along the western tip and North
Shore of Lake Superior late Sunday afternoon as the pressure
gradient increases and the marine winds become onshore.
However...have kept probability of precipitation out Sunday at this time as anticipate a
slower arrival of the moisture and higher dew points to support
saturating the low levels until the evening and overnight hours.

A southerly flow will bring a return to warm air advection across
the region Sunday night/Monday ahead of the next wave. Although
models differ in timing and amplitude of the wave this far out...the
latest GFS/ecm are suggesting convection develops ahead of the h50
trough...along a surface boundary positioned in the Northland vicinity
Monday. At this time have continued to carry small probability of precipitation through the
Sunday night/Tuesday time frame.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 655 am CDT Wednesday Oct 22 2014

Discussion...VFR conditions will through the day. An approaching
cold front will bring decreasing clouds and rain overnight. Expect
MVFR ceilings and rain to move into the kinl to kbrd areas around
00z...spreading east through the night. Expect widespread MVFR
conditions and rain after 06-08z.


Preliminary point temps/pops...
dlh 54 46 60 44 / 20 70 20 10
inl 58 47 61 39 / 50 70 10 0
brd 58 47 65 40 / 40 70 10 0
hyr 56 45 55 41 / 20 70 50 10
asx 57 45 55 42 / 20 70 60 10


Dlh watches/warnings/advisories...


short term...bjt
long term...graning

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