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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
336 PM CDT Tuesday Oct 21 2014

Short term...(this evening through Wednesday night)
issued at 310 PM CDT Tuesday Oct 21 2014

Clear skies were widespread across the upper Midwest this afternoon.
Surface high pressure across southern Ontario together with a
developing area of low pressure over southern Saskatchewan led to
southeasterly winds across the Minnesota River Valley. Boundary
layer mixing allowed surface temperatures to climb to near 70 across
western Minnesota...but low clouds limited temperatures to the middle 50s across
western WI.

Southeasterly winds will continue overnight. An upper level wave
currently located across the Idaho/Montana border will move eastward and
bring precipitation beginning late Wednesday across the west...and
shifting eastward overnight. This well advertised precipitation is now
falling into the time frame of the hires models...so tried to narrow
up the pop window...but increased the percentages as well. Forecast
soundings show some elevated instability...so could see a few
lightning strikes as well. Rainfall totals should range around 0.20
inches for most locations.

Long term...(thursday through tuesday)
issued at 310 PM CDT Tuesday Oct 21 2014

Thursday weather and the departure of the showers in ec Minnesota/wc WI will
be highly dependent on the storm system in the northeastern U.S.
And how it influences/slows the evolution of the upper Midwest
storm system.

Over the past few model runs...the storm system across the
northeast has remained consistent and holding near or south of
Boston/mass. The storm system across the upper Midwest has slightly
become more negatively tilted leading to a slower/stronger
solution. Due to the storm system in the northeast...it is likely
that the upper Midwest system may slow down further. Current
weather/pop grids reflect a slightly slower solution which may be
slowed more if conds warrant.

Past Thursday...the progressive pattern will remain across The
Rockies/northern plains/upper Midwest. Models have been consistent
in a strong upper ridge building across the southern U.S. With the
extension of this ridge across the upper Midwest. A strong
correlation of abnormally higher heights above 500 mb is evident in the
latest ensembles of the naefs. This will lead to the above normal
temperatures for the next several days past Thursday...with the best
probability of seeing another 70 degree high on both Friday and
Sunday. Depending upon the progressive pattern continuing...this
above normal anomaly of the 20/500 mb will move east by late next
week...with a more unsettled period by late October and early
November. Latest 6-10/8-14 day outlook from CPC has near normal
temperatures by early November. Early November temperatures for the upper
Midwest average around 32 degrees for morning lows and highs in
the 40s.

&&

Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1230 PM CDT Tuesday Oct 21 2014

VFR conditions today and tonight will give way to clouds Wednesday
morning across western Minnesota. Moisture profiles from several models
show the potential for MVFR clouds at kaxn...kstc...and krwf. Winds
will continue southeasterly throughout the period.

Kmsp...
VFR conditions throughout. MVFR ceilings are possible Wednesday...but
at this time do not have the confidence to put MVFR conditions in
the tafs. Looking ahead...rain will move in from the west around
00z Thursday.

/Outlook for kmsp/
Thursday...VFR with MVFR/-shra early. Winds south-southeast at 10g20kts.
Friday...VFR. Winds south-southwest at 5-10kts.
Sat...VFR. Winds northwest at 5-10kts.

&&

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

$$

Short term...jrb
long term...jlt
aviation...jrb

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