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Area forecast discussion 
National Weather Service Duluth Minnesota
403 am CDT Monday Apr 21 2014

Short term...(today and tonight)
issued at 403 am CDT Monday Apr 21 2014

Main short term forecast concerns are centered around the potential
for showers and a few isolated weak thunderstorms possibly over the
southern portions of the forecast area this morning...along with weak
rain showers to the north and patchy fog over northwest WI this morning.
Temperatures and gusty northwest winds this afternoon will also be a
challenge with another warm day expected. Will see temperatures fall
tonight and possibly a few flurries into the tip of The Arrowhead
late tonight.

High pressure at the surface is moving off to the east this morning as a
two-pronged low pressure system phases into one across the upper
Midwest/western Great Lakes area today. An upper short wave over the northern plains
early this morning will track to the east today and merge with a
broader upper wave and surface inverted trough to the south. The wave
to the north is slightly more dynamic and has shown evidence of a
well-defined surface front/wind shift line. However...the bulk of the
moisture is remaining confined to the south...and the front is
moving into a very dry air mass. So...rain showers across the north
will be weak and produce only light precipitation amts.

The upper wave and surface trough to the south will lift slightly to the
north this morning as the entire feature progresses eastward. Model
guidance is indicating enough moisture and instability could be
present to trigger scattered showers and a few isolated weak
storms. The best chance of thunder will likely be along the southern
edge of the forecast area along and south of a line from Lake
Mille lacs to Spooner to Park Falls. Convective rain showers could
extend northward to around the twin ports this morning...but will likely
be short-lived.

Patchy fog has been very isolated this morning...mainly confined to
areas of Price County. Light winds and nearly saturated surface
conditions across portions of north-central WI will lead to some
expansion of the fog this morning...with visibilities down to less than a
mile in some locations.

Another warm bubble of air will develop over the Northland
today...but be confined to areas south of the Iron Range.
Temperatures will warm into the 60s once again from Brainerd to
Duluth to Phillips. Areas to the north will have a harder time
climbing above the lower 50s as the cold air mass behind the front
slowly moves in from the northwest. Will likely see temperatures peak around 1 or
2 PM and then drop off from west to east as the full effects from
the front arrive. Winds will also strengthen today with a strong
ridge of high pressure building in over the northern plains creating a
tight pressure gradient over northern Minnesota and robust mixing develop.
Expect sustained northwest winds 20 to 25 miles per hour and gusts 25 to 35 miles per hour
possible. The strongest winds will be across Minnesota.

Temperatures will cool tonight into the upper 20s and lower 30s. A
few lingering light flurries are possible over lake and Cook
counties.

Long term...(tuesday through sunday)
issued at 403 am CDT Monday Apr 21 2014

Tuesday a surface ridge will slowly move across the area...leaving
quiet weather with high temperatures in the middle 40s to upper 50s.
The southwestern counties could be warmer...with sunshine and dry
air...but mixing is likely to be shallow which would act to keep
highs down somewhat.

Wednesday through Friday is our next major weather maker...as a slow
moving upper level low moves across the upper Midwest. This system
should start out with rain as the warm air advection pushes across
the area. Once the warm front moves through and we can get some
warmer air and instability in here...we should also get some
thunder...mainly on Wednesday night and Thursday with some fairly
steep middle level lapse rates and even some weak low level cape across
the south. Thursday night and Friday the cold air is expected to
surge into the area from the northwest...now with the GFS faster
than the European model (ecmwf). For now have kept things fairly generic with a
rain/snow mix overnight and Friday...with all snow Friday night
before the event ends. Confidence in precipitation types is improving but
still not terribly high due to model temperature and timing
differences mentioned above. For now temperatures through the
period to be colder than normal throughout.

Next weekend to be dry and cool with highs in the 40s and lows in
the 20s.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1248 am CDT Monday Apr 21 2014

Surface low and associated cool front has advanced eastward into
western Minnesota late this evening...and scattered showers have
been reported over portions of northwestern Minnesota. The front
should pass through the Minnesota terminals before 12z and through hyr
mid-morning. The best chance of showers will affect
hib...inl...and dlh after frontal passage. Kept a mention of
vcsh at brd and hyr. Clouds are streaming northward over
northwestern Wisconsin and will affect hyr overnight. Current
thinking is that mainly middle-level clouds will affect the
terminal. However...sites farther south have reported ceilings as low
as 800 feet within the last hour. Winds will be quite breezy on
Monday and have maintained higher sustained winds and gusts from
previous forecast.



&&

Preliminary point temps/pops...
dlh 60 32 52 33 / 30 0 0 0
inl 48 31 52 34 / 10 10 0 0
brd 63 33 59 38 / 10 0 0 10
hyr 65 32 54 31 / 40 0 0 0
asx 60 32 49 30 / 40 0 0 0

&&

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

$$

Short term...bjt
long term...le
aviation...huyck