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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
325 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
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
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

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


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 120 PM CDT Sat Apr 18 2015

VFR conditions will give way to MVFR...and possible IFR as storm
system currently located over the Missouri River valley will lift
northward across the upper Midwest... possible a few
thunderstorms...will overspread the region later this
evening/tonight. Latest hires guidance continues so show slower
onset of have pushed back the timing in the tafs.
Winds will become northwesterly toward the end of the taf period.

latest guidance shows the precipitation holding off until around 05z.
Winds will have an easterly component through middle morning on
Sunday...but will become northwesterly with gusts near 20kts as a
cold front pushes through the region. Ceilings should gradually
lift to VFR conditions in the wake of the front.

/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...


Short term...jrb
long term...borghoff

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