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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
654 PM CDT Sat Apr 18 2015

Short term...(this evening through sunday)
issued at 325 PM CDT Sat Apr 18 2015

Todays forecast centered around timing the precipitation as it lifts
northward from its current location along the Missouri River valley.
Latest forecast trends keep the precipitation over Minnesota...and leave western
Wisconsin mostly dry through Sunday morning until the northern
shortwave moves along the international border. As a result...it
looks light there will be 2 areas of enhanced quantitative precipitation forecast...1 along southern
Minnesota...and the other along northwestern Minnesota.

Forecast soundings show little in the way of elevated cape...and the
cape that does exist is confined to the shallow h700-500mb layer.
Therefore not expecting much thunder...and have confined it to the
southern third of the forecast area. Temperatures will be tricky on
Sunday as we should warm up ahead of the approaching cold front...so
increased temperatures slightly in south/eastern Minnesota and western WI. By
Sunday evening northwesterly winds will usher in the seasonably cold
airmass that will stick with US for upcoming week.

Long term...(sunday night through saturday)
issued at 325 PM CDT Sat Apr 18 2015

The dry slot will be firmly overhead Sunday night and we should
see a fair amount of clearing. However...double or triple barrel
low centered over the Great Lakes will send pieces of energy
southeast across northern Minnesota and WI Monday through Tuesday.
Increasing clouds will quickly return Monday morning with the
potential for scattered showers by afternoon due to steep low and
middle level lapse rates. The boundary layer will be quite dry...but
think there will be at least a few drops here and there.
Maintained probability of precipitation through Tuesday...highest north of I-94.

Strong northwest winds and much colder temperatures will be the
other main story for early week. Sustained speeds of 20-25 miles per hour
and gusts to 35 miles per hour are likely Monday and Tuesday. Despite deep
mixing...will only be able to make the upper 30s to upper 40s for
highs.

Very large area of cyclonic flow will continue across the
northeastern half of the Continental U.S. For the rest of the period. Middle
level moisture will kick out by Wednesday so at least there won't
be widespread cloudiness. However...temperatures will be a good 10
degrees below average and several light freezes are expected next
week.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 647 PM CDT Sat Apr 18 2015

Rain moving in tonight. The 00z taf reflects the best estimate on
timing. We don't think there will be much in the way of IFR...but
certainly plenty of MVFR ceilings late tonight and early tomorrow
morning. We also don't think there will be much in the way of
thunder...perhaps a few in-cloud rumbles.

Kmsp...

Not much to add...steady light rain sets in tonight and last
through the morning tomorrow. We think the visible will reach 4sm and
the ceiling should get close to 2000 feet early tomorrow
morning...but we are somewhat unsure on when specifically that
will happen. The taf represents are best estimate on timing.
Certainly looks like a soggy early morning...but there shouldn't
be much embedded thunder...so the rain will never be all that
heavy.

/Outlook for kmsp/
Monday...VFR with MVFR/-shra possible. Winds northwest at 20g35kts.
Tuesday...VFR. Winds northwest at 15g25kts.
Wednesday...VFR. Winds northwest at 15g25kts.

&&

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

$$

Short term...jrb
long term...borghoff
aviation...clf

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