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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
615 am CDT Monday Jul 28 2014

Update...for 12z aviation discussion below


Short term...(today and tonight)
issued at 349 am CDT Monday Jul 28 2014

The primary short term concerns revolve around the influence that
weak shortwave energy trapped between the eastern trough and the
western ridge will have on local precipitation chances and
temperatures today.

Cloud cover has remained quite extensive across the forecast area
overnight as cyclonic flow continues...with scattered sprinkles and light
rain showers along/east of the Buffalo Ridge refusing to give up as
weak 700-600mb frontogenesis persists. Expect the cloud cover to
linger through much of the day with little change in the pattern
anticipated. Weak shortwave energy continues to spill across west
and south central Minnesota today...which will likely prove sufficient to
spawn scattered showers along the Minnesota River Valley into south central
Minnesota during the late morning and afternoon hours. Due to the anticipation
of more extensive cloud cover today...have lowered forecast highs to
between 70 and 75 degrees.

Should see a clearer night tonight with the weak channel of
shortwave energy expected to sag west/southwest of the area. Lows should dip
into the low to middle 50s in most areas...with upper 50s in the Twin
Cities metropolitan area.

Long term...(tuesday through sunday)
issued at 349 am CDT Monday Jul 28 2014

A persistent upper level ridge will become parked across the Rocky
Mountains. This will lead to northwest flow...upper level
subsidence...surface high pressure...dry conditions...and light
winds across the upper Midwest. Temperatures will be right near
the seasonal average of 80f.

Weak shortwaves associated with the upper level trough over the
Great Lakes gives some legitimacy to the slight chance of probability of precipitation that
periodically appear across eastern Minnesota and western WI. At this time
the best chance appears to be Friday...with a higher likelihood the
farther east you go. Forecast soundings off the GFS show total cin
erosion and 250 to 500j/kg of sb cape by late afternoon both
Thursday and could see a few high based showers or
thunderstorms...but confidence is high that widespread precipitation will
not occur. In short...the run total quantitative precipitation forecast from both the 28.00 GFS and
European model (ecmwf) ranges in the 0.05 to 0.10 inches. In reality...most locations
will not see any measurable precipitation through at least the early part
of next week.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 615 am CDT Monday Jul 28 2014

A broken-overcast deck of low-end VFR clouds /circa 6kft/ will loiter
across the taf area through the morning hours...with scattering
expected to occur this afternoon. A few light rain showers will
also be possible near krwf...but visibilities should remain VFR. Skies
become mostly clear tonight and northwest winds decrease below 5

broken-overcast clouds circa 6kft this morning....then scattering occurs
this afternoon. Northwest winds around 9 kts through the
day...decrease to at or below 5 kts after 00z.

/Outlook for kmsp/
Tuesday...VFR. Winds northwest 10 kts.
Wednesday...VFR. Winds northwest 5-10 kts.
Thursday...VFR. Winds north 5 kts.


Mpx watches/warnings/advisories...


long term...jrb

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