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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
103 am CDT Thursday Jul 2 2015

Short term...(this evening through thursday)
issued at 320 PM CDT Wednesday Jul 1 2015

The short term concern remains timing of next short wave across
the Dakotas into far western Minnesota late tonight into Thursday.

Water vapor imagery and radar trends showing short wave exiting
southern Minnesota taking the light rain/sprinkles with it. This
should leave a lull in the precipitation threat of the area until
later tonight when the short wave arrives. The 18z nam_wrf and
European model (ecmwf) do bring some light quantitative precipitation forecast into far southwest into Thursday as
the wave moves through. Most of the cams/hires models generate
more concentrated convection over South Dakota late and drives
most of the precipitation south of the area. Models havent been
handling this northwest flow pattern very will continue
to hold onto the chance probability of precipitation into the southwest areas into
Thursday...working over the south through the afternoon. Thunder
threat rather low once gain...with better instability remains to
the west and south of the area. Mentioned just isolated thunder
threat into Thursday. Expect something similar to today in cloud
trend overall...with thicker clouds moving into the west mainly
after 06z Thursday. Farther east...less cloud expected along with light
wind...should radiate pretty well again with light winds under the
surface ridge. Will mention some patchy fog into the east as dewpoints are expected to be a little higher and clouds
less than last night.

Clouds should thin to the east and northern County Warning Area during the
day...decreasing in the south in the afternoon once again. Expect
temperatures to warm through the 70s with more sunshine to the

Long term...(thursday night through wednesday)
issued at 320 PM CDT Wednesday Jul 1 2015

The large scale flow looks to undergo some changes as we head into
the longer term... although the guidance show some significant
differences beyond day 6 and 7. In general... the western ridge
still looks to retrograde westward over the weekend as a fairly
substantial shortwave currently in the Gulf of Alaska pushes east
then southeast into the upper Midwest. This looks to be our
primary weather maker during the period... bringing a cold front
through the region during the Sunday/Monday time frame. Prior to
that... we/ll see a piece of this shortwave... which is currently
shearing off into northwest Canada... work by to our north on
Friday. That feature will attempt to push a front through the
area... but it doesn/T look to dig sufficiently south to push it
through more than the north/central portion of the area. As
mentioned... the guidance starts to diverge significantly toward
the latter portion of the forecast... with the differences
initially becoming notable with the Sunday system. The GFS
continues to be more progressive than the European model (ecmwf) and Canadian...
and brings the upper wave into the area later Sunday... pushing
the cold front across our area Sunday afternoon/evening. The European model (ecmwf)
and Canadian are about 12 hours slower... resulting in warmer
temperatures on Sunday... and a reduced chance of severe weather
given their nocturnal/early morning frontal passage. The hopwrf-ts... using
GFS for initial/boundary conditions... develops some decent
looking convection across the area with a Sunday afternoon/evening
frontal passage... initially forming over northeast Minnesota where the cap
would be weaker... but then continuing down along the front into
southwest Minnesota. Needless to say... the details will
undoubtedly be much different... with things depending on the
timing of the front... and the southward extension of the better
forcing associated with the upper wave. After the Sunday/Monday
system... it looks like a good upper low will close off to our
north over central Canada. However... the GFS is much farther
south in comparison to the European model (ecmwf)... resulting in things cooling
down quite a bit during the middle to end of the week in
comparison to the European model (ecmwf) which looks like it would keep the
baroclinic zone to our north.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1238 am CDT Thursday Jul 2 2015

Medium to high confidence in VFR conditions with just a few
passing high clouds. There is a chance for some light fog at
kstc/krnh/Keau this morning given the clear skies and light/calm
wind. At krwf and kaxn


VFR with no aviation weather concerns. Light winds throughout the
taf period.

/Outlook for kmsp/

Friday...VFR. Slight chance -shra. Winds west-southwest 5-10 kts.
Sat...VFR. Winds SW 5-10 kts.
Sun...VFR. Chance of MVFR with -tsra late. Winds S 10-15 kts.


Mpx watches/warnings/advisories...


Short term...dwe
long term...trh

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