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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
330 am CDT Friday Jul 25 2014

Short term...(today and tonight)
issued at 330 am CDT Friday Jul 25 2014

Early morning thunderstorms continued to develop across the region
this morning fueled by the veering winds associated with the theta_e
advection in connection with the low level jet. Over the next few
hours this 40kt jet will become more focused across southern...and
eventually southeastern Minnesota. As a result precipitation will continue
to develop for the next few hours...but should gradually wane
shortly after sunset as it enters western WI.

Earlier runs of the rap missed the precipitation that developed in
northeast South Dakota...so it is no surprise that highres models have been
struggling to get a handle on the two areas of precipitation that developed
earlier. As a result most of the runs have been all but discarded.
The 25.06hrrr has finally caught up and it supports the idea of
continued convection this morning...but with a weakening trend after
11z. The severe weather threat is very low given the deep stable
layer beneath the elevated cape...and only marginal 30-35kts of
effective shear.

Looking ahead...skies should clear behind the morning precipitation
yielding another muggy afternoon as dewpoints climb back to near
70f. Increased temperatures slightly across west of i35...and raised
dewpoints as well. Overnight northwesterly winds will push a cold
front through the region sending dewpoints back into the upper 50s
by Saturday morning.

Long term...(saturday through thursday)
issued at 330 am CDT Friday Jul 25 2014

The weekend starts out on a mild note...as the area remains
sandwiched between a southern Continental U.S. Ridge to the south...and a
middle level low to the north in Saskatchewan/Manitoba. The result will
be slightly warmer than normal highs in the middle 80s on
Saturday...followed by increasing precipitation chances into
Sunday as the aforementioned low drops south-southeast from
southern Manitoba. As is common with these types of
lows...precipitation chances appear the highest from central Minnesota
into WI...where forcing/moisture is deeper. Expect showers with
isolated thunderstorms on Sunday...particularly during the afternoon
hours as diurnal heating aids destabilization.

Next week starts out on a dry and mild note as the weekend low
shifts southeast and a broad surface ridge builds across the
central Continental U.S.. the local area remains crammed between western
ridging and eastern troughing at the middle to upper levels of the
atmosphere...yielding cooler than normal highs from Monday through
Wednesday mostly in the 70s...and lows in the 50s.

Thursday and Friday bring the next chance for measurable
precipitation as shortwave energy begins to trickle south on the
western periphery of the eastern Continental U.S. Trough. Chances are not
high at this point given modest forcing and moisture...but
sufficient for the inclusion of 20-30 probability of precipitation.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1059 PM CDT Thursday Jul 24 2014

Confidence has increased quite a bit in the last few hours with
regard to the precipitation evolution overnight into early Friday
morning. Expect to see showers and thunderstorms rapidly develop
around 07z across southwestern Minnesota and expand eastward in the hours
following...reaching stc around 09z...msp around 10z...and rnh by
11z. Some thunder may accompany this precipitation...especially across
southern and western Minnesota. Any shower/storm activity should diminish
2 to 4 hours after it begins. Following the precipitation...models insist
on developing IFR or MVFR ceilings. Not confident in this scenario as
they have overdone these events time and time again this Summer.
Will continue the scattered mention around 2 kft before ceilings rise toward
4 kft by afternoon.

Kmsp...current projections indicate precipitation will arrive at msp
around 10z and persist through about 12 or 13z. Confidence has
increased and brought back the prevailing group for this
timeframe.

/Outlook for kmsp/
Sat...VFR. Winds west-southwest at 5-10kts.
Sun...VFR. Chance rain showers/MVFR ceilings. Winds northwest at 10-15 kts.
Monday...VFR. Winds north 5 knots.



&&

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

$$

Short term...jrb
long term...ls
aviation...borghoff

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