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Area forecast discussion...updated 
National Weather Service Twin Cities/Chanhassen Minnesota
646 PM CDT Thursday Mar 26 2015

Short term...(this evening through friday)
issued at 330 PM CDT Thursday Mar 26 2015

Quiet short term period ahead with low clouds across the area
advancing southward through the state and skies quickly clearing in
northern Minnesota as dry air advances south in conjunction with a
surface high that will advance into the area by Friday morning.
Skies will clear from north central Minnesota this afternoon...through
southern Minnesota by tonight. By tomorrow morning...850mb temperatures will
range from about -10c in western Minnesota to -16c in western WI. With
clearing skies and calm winds...temperatures will be quite cold
tonight...single digits are a possibility in some spots through the
area that the heavies snow fell earlier in the week.

Tomorrow will see more sunshine but with the cool Canadian air mass
in place...temperatures will be held about 10 degrees below normal.
At the very end of the short term period...a warm air advection band of lift may
begin pushing light precipitation into extra western Minnesota. Further
east...limited lift and the dry air mass will keep conditions dry.

Long term...(friday night through thursday)
issued at 330 PM CDT Thursday Mar 26 2015

Main changes in the extended period is to continue increasing chance/S
of precipitation late Saturday night and into Sunday morning. Main
dilemma is the lack of consistency between the GFS/ec/Gem shortwave
and associated surface low reflection and precipitation field. This
weekend system is still off the coast of Washington state which
means that upper air analysis is not complete in the current model
data. Would like to see two more runs...or at least once it comes
onshore before we have a much better picture in terms of how
widespread the precipitation becomes. Although this shortwave is
quite impressive via WV imagery this afternoon...am still hesitant to
go categorical for precipitation chc/S. If this feature has more
energy then current models suggest...the surface low maybe stronger
and further to the south across the Dakotas/MN. This will lead to
a better organization of precipitation and stronger winds. The
wind energy with this system is already impressive and current
model guidance does support 25-35 miles per hour sustained winds Sunday
/gusts approaching 50 miles per hour/ across western Minnesota. Will need to watch
this scenario and highlight winds in the severe weather potential statement. We may need to issue
a high wind watch Sunday depending upon the strength of the
pressure gradient. In addition...if less moisture develops and
associated precipitation fields are not overwhelming...an increase
in fire weather concerns is likely in SW Minnesota for Sunday afternoon.

Will lean toward the 500 mb GFS ensemble mean for guidance past
Monday as another strong shortwave moves across the northern U.S. By
midweek. Boundary layer moisture is much higher compared to this
weekend system...and may even be enough to generate our first
convection along the Iowa/Minnesota border Wednesday afternoon ahead of a cold front.

No other changes are forecast past Wednesday with both GFS/ec
indicating the mean upper air flow will become more northwest...leading
to cooler air for the first week of April.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 645 PM CDT Thursday Mar 26 2015

VFR conditions expected. Bank of stratocu is pushing south and
will clear all the taf sites shortly after the beginning of the
taf period. Clear skies to follow into Friday...with increasing
middle level clouds during the afternoon across Minnesota. North winds will
ease tonight and become light south Friday.

Kmsp...no additional concerns.

/Outlook for kmsp/
Sat...MVFR possible with chance -ra/-sn late. Winds S 10-15 kts.
Sun...VFR. Precipitation departing east in the morning...skies clearing
in the afternoon. Winds turning northwest 20-25g35kts.
Monday...MVFR possible...winds west 5-10kts.

&&

Mpx watches/warnings/advisories...
Minnesota...none.
WI...none.
&&

$$

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

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