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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
635 PM CDT Monday Jun 1 2015

Short term...(this evening through tuesday)
issued at 236 PM CDT Monday Jun 1 2015

The short term concern is showers/thunder threat over the northwest
County Warning Area Tuesday.

Little concern into tonight with some middle/high level clouds moving
through. Those middle/high level clouds remain over the northwest part
of the County Warning Area in westerly upper level flow pattern. Upstream...models
indicate a short wave trough lifting across eastern Montana later
this evening...and generating a small thunderstorm complex over the
Dakotas. Timing of this occurring is difficult to discern at this
time. A few hires cams do bring complex into the eastern Dakotas by
12z Tuesday. The European model (ecmwf)/GFS handle this system similarly and believe
activity will gradually wane over the eastern Dakotas/northwest Minnesota
Tuesday morning. The instability ridge remains over far western Minnesota
into the afternoon...with strong moisture transport into that
area into the morning. Will continue the small chance probability of precipitation
developing into Tuesday for now due to continued timing
uncertainty.

Depending on cloud cover into Tuesday...high temperatures are
expected to mix to around 850mb which would yield some middle/upper 70s
to parts of the area.

Long term...(tuesday night through monday)
issued at 236 PM CDT Monday Jun 1 2015

The long term period will start off on an active note...with
decent agreement amongst medium range models that a surface low
will be straddling the central Dakotas on Tuesday evening. The
attendant warm front will lift into central Minnesota overnight
into Wednesday morning...with increasing confidence that showers
and thunderstorms will Blossom over the area overnight as low level
moisture convergence expands into the region on the nose of the
35-40kt low level jet. Will also have upper support as illustrated
by 400mb pv advection spreading eastward across the area through
the day...which should help sustain convection even as the
nocturnal low level jet wanes. By Wednesday afternoon...the cold front is
prognosticated to be bisecting the forecast area. This would be the
window of opportunity for strong to severe storms...although shear
is marginal and destabilization could be hindered by convective
debris from overnight/morning activity. By Wednesday
night...expect most of the storms to be east of the Interstate 35
corridor. Thursday is a mess with respect to model agreement. Tend
to prefer the drier 01.12z European model (ecmwf) and NAM solutions...which keep
the bulk of the precipitation to the south in Iowa. The GFS seems
to be too far north and overdone with its quantitative precipitation forecast. Have maintained
20-40 probability of precipitation for Thursday...but it is entirely possible that will
be adjusted in future forecasts to keep chance probability of precipitation along/south
of the Minnesota-Iowa border. Tend to think Friday will trend drier as
well...with model trends shifting the precipitation east/south with time.

Saturday looks to be the dry day of the weekend...but then the GFS
and European model (ecmwf) models show pretty decent agreement in the next
/stronger/ trough moving across the Dakotas and northern Minnesota...and
spreading showers and thunderstorms across the area between 03z
and 18z Sunday. They then diverge a bit from Sunday afternoon and
beyond regarding the evolution of the trough...but have rather
high confidence in precipitation for the Saturday night-Sunday
morning time frame.

&&

Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 630 PM CDT Monday Jun 1 2015

Mainly scattered high clouds will persist tonight...with winds
remaining out of the southeast through the remainder of the
period. Strongest winds will be located in western Minnesota...especially
during the late morning and afternoon Tuesday when gusts to 25-30
kts are likely at axn and rwf. Ceilings will gradually lower
throughout the day...but VFR conditions will likely persist
through the remainder of the period. One possible exception could
be at axn after 21z...when scattered showers and thunderstorms
could develop...possibly resulting in brief periods of MVFR/IFR at
this terminal.

Kmsp...VFR conditions are expected throughout the period. Winds
will remain southeasterly...with gusts increasing to around 20
kts Tuesday late morning and afternoon. Lower clouds could
increase near the end of the period...between 03z-06z on Tuesday
night...but ceilings should remain at VFR levels.

/Outlook for kmsp/
Tuesday night...VFR with MVFR/-tsra possible late. Wind south-southeast 10-15 kts.
Wednesday...VFR with MVFR/IFR possible in thunderstorms and rain. Wind S 10 kts.
Thursday...VFR with MVFR/IFR possible in thunderstorms and rain. Wind variable 5 kts.

&&

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

$$

Short term...dwe
long term...ls
aviation...additional

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