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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
630 PM CDT Thursday Jul 30 2015

Short term...(this evening through friday)
issued at 305 PM CDT Thursday Jul 30 2015

Not much change to the forecast. Early afternoon radar and satellite
imagery showed a few areas of deep convection across The Arrowhead
of Minnesota and northern Wisconsin. This matched up well with h850
temperatures northeast (cooler than) of the 14c isotherm. Here the Storm Prediction Center
mesoanalysis Page showed 500 to 1000 j/kg of uncapped mixed layer
cape.

Forecast soundings show warming middle levels throughout the
afternoon across the forecast area...so not anticipating any
development in central Minnesota. A few showers may clip far western
counties of the forecast area in Wisconsin...but coverage will be
very scarce. Later this evening westerly wind gusts will taper
off...and overnight lows will drop into the upper 50s...except in
the metropolitan where temperatures will hang on into the lower 60s. Looking
ahead to Friday...expect another dry and sunny day similar to
today.

Long term...(friday night through thursday)
issued at 305 PM CDT Thursday Jul 30 2015

A northwest flow pattern will prevail across the forecast area during the
first half of the long term with the pattern becoming more
northerly during the latter half (tuesday-thursday). Temperatures
will be at or above seasonal levels through the weekend as h850
temperatures of 15-20 degree c cover the forecast area from northeast to
southwest respectively. As time progresses...the 850mb
temperatures will cool into the 10-15 degree c range...with highs
more in the middle to upper 70s from Tuesday Onward.

There will be several short waves in the northwest flow that will
impact the region during the forecast period. The first and
perhaps strongest (with regards to severe weather) will be
Saturday afternoon and night. A surface wave will be riding
southeast through the Dakotas on Saturday with a warm front
initially heading our way...followed by a cold front during the
evening. Fairly unstable conditions are prognosticated across the
southern third of Minnesota late on Saturday. A core of 50 knot 500mb
winds are noted across southern Minnesota and northern Iowa. Deep layer
shear values are at at or above 40 knots. The Storm Prediction Center outlook of marginal
covers the area well but portions may need to be upgraded to
slight as this is a vigorous wave moving through during peak
heating. Filtered cwasp values are quite high...especially along
the I-90 corridor.

Another weaker wave will move through on Sunday...a little farther
to the northeast...with some small probability of precipitation mainly along and east of
I-94. Dry weather will take hold for Monday and Tuesday along with
a cooling trend in the high temperatures as the flow aloft begins
to turn more northerly. Finally...another wave will move through
in the middle to late week period. The GFS and European model (ecmwf) differ on how
far east the significant precipitation reaches. The GFS is more
across the Twin Cities while the European model (ecmwf) is more aligned with the
Minnesota River Valley. Hence...low chance probability of precipitation cover the forecast area with the
highest along and west of the Minnesota River Valley.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 630 PM CDT Thursday Jul 30 2015

Friday will pretty much be a repeat of today...with wind speeds
following a similar diurnal trend...with speeds/gusts similar to
what we saw today. No concerns are expected with high confidence
in a mostly clear VFR period unfolding.

Kmsp...no additional concerns to what was mentioned above.

/Outlook for kmsp/
Sat...VFR. With -tsra possible late. Winds west 5-10kt.
Sun...VFR. Wind SW at 5-10kt.
Monday...VFR. Wind northwest at 10g20kt.

&&

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

$$

Short term...jrb
long term...rah
aviation...mpg

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