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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
421 am CDT Friday Jul 11 2014

Short term...(today and tonight)
issued at 313 am CDT Friday Jul 11 2014

The morning convection will continue for several more hours...but
gradually weaken with time as the low level jet subsides and slides to the
east. We expect at least partly cloudy skies by the afternoon and
warm temperatures...especially in western Minnesota where middle to upper
80s are expected under the northward extension of the thermal

Surface boundaries are noticeably lacking across the forecast area
with the surface low and cold front hanging back across the
Dakotas. However...there remains a fairly extensive area of
showers and storms stretching from southwest NE to Lake Superior
this morning. This follows a nice corridor of 925-850mb moisture
transport in response to a 35-45kt low level jet jet. The Merriman profiler
around midnight showed 45kts at 850mb. This same corridor of
moisture advection is also collocated with an axis of precipitable waters
between 1.6"-1.9". The most vigorous convection locally is being
driven by a shortwave that made it's way out of the Dakotas last
night. Rainfall of 1-4" has fallen across much of Douglas...Todd
and Morrison this morning due to the continual redevelopment of
convection near or just ahead of the 850-300mb thickness ridge.
This ridge does transverse the entire forecast area today...but
with the low level jet decreasing and the convection out-running the best
MUCAPE...chance probability of precipitation are probably the best fit after 12z this
morning at a vast majority of locations. A weak surface remains
southwest tonight and the flow turns quite baggy overnight. This
could set the stage for fog early Saturday morning.

Long term...(saturday through thursday)
issued at 313 am CDT Friday Jul 11 2014

A weak cold front will drop through the region during the day on
Sat...leading to the highest advertised probability of precipitation in the extended
period. Periods of shwrs/tstms...particularly over southern Minnesota into
southwestern WI...can be expected for Sat afternoon-evening before the weather settles
down going into Sat night and sun as the cold front departs. This cold
frontal passage will also be the start of the southward movement of a very deep
upper level low pressure center from central Canada. A more potent cold front
will drop through the region late sun into Monday...and it is this cold front
in conjunction with the deep cold pool of air plunging into the
upper miss River Valley and Great Lakes regions that will make the
most significant change in the weather. A few showers may linger sun into
Monday with the strong cold frontal passage and the upper low ovhd. In fact... on
Monday...with the close proximity of the upper low and several shtwv
disturbance rotating around the western fringes of this upper low and across
the mpx County warning forecast area...some showers with graupel cannot be ruled out due to
the ample cold air aloft. Regardless of this potential...the main
story with this frontal passage and cold upper level low will be the very
noticeable drop in temperatures for the start of next week. 850 mb temperatures
will drop to between 4 and 6 degree c...which when translated to the
surface...spell highs only in the 60s on Monday and Tuesday. Gradual
moderation is expected through the middle of next week but this will
only push high temperatures into the low 70s on Wednesday then to the middle 70s
on Thursday. conjunction with this cooldown will be an
expansive and fairly persistent high pressure dome across the area which
will prevent any precipitation from developing for late Tuesday on through
the rest of the week.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1046 PM CDT Thursday Jul 10 2014

Showers and isolated thunderstorms are increasing late this
evening across central areas of Minnesota. This activity is expected to
expand south and toward krwf and kstc by 09z. Still appears to be
a few hours of on and off showers and thunderstorms. The picture
is not as clear for the Twin Cities and points east. It may take
until around 12z for any substantial showers to reach kmsp and
through 16z on over to Keau. Confidence has increased enough to
indicate a few hours of MVFR ceilings (025-030) at kaxn...kstc and
krwf Friday morning in the moist southerly flow. Lowest indicated
ceilings for kmsp and points east on Friday was 035. Much of the
rain showers/thunderstorms and rain activity should be over by Friday afternoon with the
exception of Keau where a prob30 group was used.

Kmsp...organized showers and a few thunderstorms not expected
until after 11z. Scattered showers and near MVFR ceilings (035)
indicated for the late morning with dry conditions thereafter.

/Outlook for kmsp/
Sat...VFR with MVFR/shra/tsra possible. Wind northwest at 5 kts.
Sun...VFR with MVFR/shra/tsra possible. Winds west at 5-10 kts.
Monday...VFR with MVFR ceilings/rain showers possible. Wind northwest at 10-20 kts.


Mpx watches/warnings/advisories...


Short term...clf
long term...jpc

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