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Area forecast discussion...updated 
National Weather Service Twin Cities/Chanhassen Minnesota
700 PM CDT Friday Apr 17 2015

Short term...(this evening through saturday)
issued at 325 PM CDT Friday Apr 17 2015

Pleasant weather continues across the region. Light winds for the
most part but relative humidity has been in the teens over parts
of western Minnesota. This will work east overnight as high
pressure moves east over the Great Lakes. Expect dry relative
humidity to develop once again over a small part of west central
Wisconsin Saturday afternoon. Fire weather criteria wont all be
met...but will have to monitor conditions and possibly collaborate
a headline for Saturday afternoon. Increasing threat of showers
Saturday afternoon and Saturday night across mainly the Minnesota portion
of the County Warning Area...ahead of the upper circulation that is prognosticated to
increase moisture from the southwest Continental U.S. Cutoff and the
incoming northern stream trough. Thunder threat low and isolated
thunder a threat into southwest Minnesota Saturday afternoon.

Temperatures may be held down some as clouds increase from the
west ahead of the system Saturday. Kept readings in the middle/upper
60s through Saturday afternoon.

Long term...(saturday night through friday)
issued at 325 PM CDT Friday Apr 17 2015

Cloudy and cool conditions will persist through most of the
extended. The cold air aloft will support afternoon cloud
development. A few rain/snow showers are possible...but
accumulations will be fairly negligible in comparison to this
weekends precipitation.

The main challenge in this period was the models handling of the
two pv anomalies. The cutoff low will be the primary precipitation
driver...while the northern stream shortwave will drive the cold air
advection and northwesterly winds. If the northern stream shortwave
is stronger and faster...per the 17... precipitation
totals will be less. However...if the northern stream wave is
weaker...than there would be more interaction with the cutoff
low...and this would allow for a longer duration of upper level
forcing and higher quantitative precipitation forecast totals.

Looking upper level low will set up across Ontario...with
the southwestern strip of vorticity situated over MN/WI. A few weak
shortwave could produce some light quantitative precipitation forecast...but for now opted toward
the drier side of guidance. Temperatures will run around 10 degrees
below the seasonal average for late April.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 655 PM CDT Friday Apr 17 2015

VFR conditions expected through the period. Middle/high level clouds
will increase Saturday with rain pushing in at the end of day or
during the evening. Light winds tonight will become east and
increase Saturday with gusts to 20 knots. additional concerns.

/Outlook for kmsp/
sun...MVFR/-ra with IFR possible. Winds southeast at 10-15 kts becoming
northwest at 10-20kts.
Monday...VFR with MVFR/-ra possible. Winds northwest at 20g35 kts.
Tuesday...VFR. Winds northwest 20g30 kts.


Mpx watches/warnings/advisories...


Short term...dwe
long term...jrb

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