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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
414 am CDT Thursday Apr 17 2014

Short term...(today and tonight)
issued at 414 am CDT Thursday Apr 17 2014

Early this morning...weakening surface low was moving east near La
Crosse, WI. This low will rapidly weaken as it moves across
Wisconsin today...but north to northwest winds across Minnesota will
remain blustery early this morning before the weakening pressure
gradient allows them to subside some. A mix of rain and snow across
west central Wisconsin early this morning will quickly dissipate and
move east over the next few hours. The tough part of this forecast
period includes predicting the extent of the stratus deck
today...and the maximum temperatures today considering all the fresh
snow cover and the pesky low clouds. The cloud cover looks to linger
across east central Minnesota through south central Minnesota...and west central
WI...while western and northwestern Minnesota remain partly cloudy. Lowered
temperatures slightly from most guidance across the snow pack...but
didn't go too crazy with that because it is middle April and deep
mixing can still occur in this situation. Otherwise...surface ridge
of high pressure builds in this afternoon and winds become calm this
evening under the ridge axis...another cool night is forecast with
sub-freezing temperatures expected across the forecast area.

Long term...(friday through wednesday)
issued at 414 am CDT Thursday Apr 17 2014

Surface ridging will push east early Friday with southeasterly
wind increasing through the day. A warm front pushing northeast
into far southwestern Minnesota may kick off a few showers over central
and western Minnesota. Models have been trending drier with the most
recent NAM now almost completely dry. Maintained slight chance
probability of precipitation...but they could be removed in future forecasts. Cloud cover
will be extensive in strong warm air advection environment...and when coupled
with increasing southeasterly wind and residual snow cover...will
bring a chilly day with highs in the 40s...except some 50s near
the Iowa border depending how far north the front can lift during
the day. Temperatures will drop off Friday evening before becoming
steady or slowly rise overnight following the passage of the warm
front.

Low pressure will trek north across the Dakotas into southern
Manitoba Saturday. A cold front will stretch to the south into the
Midwest and eastern plains...but forcing will be weak with much of
the energy being deflected to the north. Not particularly excited
about shower chances Saturday...but they will be best across
central Minnesota. If some sun can break through...highs will reach the
60s which could tap enough elevated instability for a low
probability of thunder.

The front will slow Saturday night...eventually washing out across
the Great Lakes and middle Missouri Valley Sunday. Shower chances
will linger near this front across southeastern Minnesota and western WI. The rest of
the region will see clearing skies. Mild Pacific air will push
across the plains during this time and plentiful sunshine in much
of Minnesota will bring temperatures back into the 60s or low 70s.

Thermal ridging arrives Monday as 925 mb temperatures rise into the +14
to +16c range. Mixing to 850 mb will take full advantage of this
thermal ridging and temperatures will climb into the middle 60s to middle 70s.

As strong low pressure develops over the northern rockies by middle
week...the warm front will retreat and winds will back
easterly/southeasterly. This will mark a trend toward cooler temperatures
at least temporarily midweek...particularly as a band of showers
and thunderstorms develop north of the boundary. Very warm and
humid air in the warm sector will try to make an appearance by
Thursday pending the track of the low. This will bring increasing
severe weather chances...which bears watching.

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 116 am CDT Thursday Apr 17 2014

The precipitation has come to an end across most of Minnesota
(except the far east, including msp) and the stratus deck is on
the move. Clear skies have already reached axn had subsidence and
dry air advection continues in that area. The snow/rain intensity
will diminish overnight and come to an end across eastern
Minnesota...then western WI. The tricky aspect of this forecast
package...is how quickly we shed the stratus deck. Hi-res guidance
indicates low level moisture to remain high across eastern Minnesota and
western WI through much of today. Not very confident in this
solution though...as this guidance is overdone with current cloud
cover. The clearing line to the northwest has slowed...but is
still pushing southeast...and may reach the west metropolitan before
halting and even back-filling. Currently excepting MVFR to linger
at most sites (except axn and rwf) winds will generally be northwest
during the period as the surface low pushes off across Wisconsin.

Kmsp...snow will end prior to 08z at msp. Hi-res guidance
indicating MVFR ceilings into the afternoon today...but confidence
in this lacks. Will closely monitor the progression of the stratus
deck...as this actually could go VFR much quicker than currently
advertised in the taf.

/Outlook for kmsp/
Friday...mainly VFR. Chance MVFR Friday night with -ra. Winds NE 5-10 kts.
Sat...mainly VFR. Chance MVFR with -ra. Winds east-southeast 10-15 kts.
Sun...VFR. Winds north-northeast 5-10 kts.



&&

Mpx watches/warnings/advisories...
Minnesota...none.
WI...Winter Weather Advisory until 7 am CDT this morning for wiz025-
027.

Winter Storm Warning until 7 am CDT this morning for wiz015-016.

&&

$$

Short term...speed
long term...borghoff
aviation...speed