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fxus63 kmpx 180439 
afdmpx

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1139 PM CDT Thu Oct 17 2019

Updated for 06z aviation discussion...
issued at 1137 PM CDT Thu Oct 17 2019

&&

Short term...(this evening through Friday night)
issued at 350 PM CDT Thu Oct 17 2019

Forecast concern near term is extent of warming Friday and shower
threat into Friday night.

Surface high pressure ridge exiting the eastern area overnight.
Increasing pressure gradient developing to the west ahead of a
developing frontal system over the Dakotas. This will increase winds
from west to east overnight with gusts likely most of the night over
the western County Warning Area. Some mid/high level clouds should work east over
the Dakotas and over Minnesota tonight and Friday. With the wind and
some high clouds, overnight lows should drop below he 40 degree mark
in Minnesota, with perhaps some upper 30s in west central Wisconsin.

It appears moisture will be slow to return so, even if the front
works into far western Minnesota late afternoon, we expect it to
remain dry. Extent of cloudiness will determine how warm we it will
be Friday afternoon. Good southerly wind and warmer low level
temperatures 925mb from 10-15c across the southwest cwa, should
boost temperatures through the mid/upper 60s.

As the front works into western Minnesota, the upper trough brings in some
channeled fgen, and this works east into western Wisconsin Friday
night. We will likely see at least a band of very light rain as it
works into central/Easter County Warning Area later in the night per latest trend of
hires models. We will carry some lower chance pops for this as it
moves east. We dont expect anything heavy, generally less than one
tenth of an inch.

Long term...(saturday through thursday)
issued at 350 PM CDT Thu Oct 17 2019

Pleasant weather will continue through most of the weekend with a
mild atmosphere in place. Highs in the mid 50s to mid 60s are
expected both days with abundant sunshine on Saturday.

The weather takes a turn by Sunday night as a trough over the
western U.S. Deepens significantly Sunday before tracking
northeast across the upper Midwest Sunday night and Monday. Model
variability remains problematic with respect to temporal and
spatial differences in precipitation, which prevented pops from
being increased as high as they should be at some point during
this period (nearly 100%). A band of rain will swing through in
advance of the low pressure center, followed by a dry slot which
should shut down the steadier rain into areas of drizzle across
much of the area by late Monday morning-ish. The exception may be
across western Minnesota in the deformation band. This deformation band
will then swing east across the remainder of the area for a second
round of steadier rain later Monday afternoon and evening. This
is also when westerly winds will increase significantly with gusts
of 35-40 mph. The atmosphere should be too warm to support much
snow, although a few flurries are possible over west central Minnesota
late Monday night if the precip lingers that long.

Winds will subside later Tuesday as a surface ridge moves in
briefly ahead of the next system. This one has a lot of question
Marks with it too since models vary significantly on potential
solutions. These solutions range from a stripe of accumulating
snow on the northern end of the system, to a warm and weaker
clipper system that struggles to develop into much. It will be a
while before we have an idea, but for now chance pops are
justified.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1137 PM CDT Thu Oct 17 2019

VFR conditions throughout. A strong low level jet will leading
to some turbulence and wind shear overnight. Surface winds will
gust again Friday afternoon as clouds move in from the west.

Kmsp...

VFR conditions throughout. A strong low level jet will leading
to some turbulence and wind shear overnight. Surface winds will
gust again Friday afternoon as clouds move in from the west.

/Outlook for kmsp/
Sat...VFR. Rain showers possible late. Wind west 5-10 kts.
Sun...VFR with MVFR/IFR/-shra late. Winds southeast at 15g25 kts
Mon...IFR/-shra early, then MVFR. Wind northwest at 20g30 kts.

&&

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

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