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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
1102 PM CDT Tuesday Jul 7 2015

issued at 1051 PM CDT Tuesday Jul 7 2015

Updated to include 06z aviation discussion below.


Short term...(this evening through wednesday)
issued at 405 PM CDT Tuesday Jul 7 2015

Benign weather is expected during the short term forecast broad high pressure prevails across the upper
Mississippi Valley. The one pesky feature during this time frame
will be a bit of smoke filtering in again tonight and
Wednesday...although it should remain mainly high level and
primarily result in a milky sky and unrestricted visibilities.
Patchy fog will also be possible overnight in west central
Wisconsin in areas that received the heavy rainfall Sunday night
into Monday.

Highs on Wednesday will moderate a few degrees into the middle 70s
with a more southerly flow developing...with cumulus cloud
development possible again by late morning Wednesday.

Long term...(wednesday night through tuesday)
issued at 405 PM CDT Tuesday Jul 7 2015

Overall the main forecast concerns will be precipitation chance/S
over the weekend and heat index values.

Abnormally low dew points initially will rise again by the weekend
with heat index values becoming an issue. Best chance/S of rainfall
will occur late Friday/early Saturday and again late Sunday/early

Wednesday night/Thursday the upper Midwest will be cutoff between
two weather system that will kept mpx County Warning Area dry and slightly cooler than
normal. A weakening front will stall and wash out across wc/northwest Minnesota
Wednesday evening while another system moves NE across the middle
Mississippi Valley and into the Ohio Valley.

Differences in the models /ec/Gem/GFS/ become apparent late in the
week for an old frontal boundary lifting northeast across the
middle section of the nation. GFS is more aggressive with the front
lifting NE across mpx County Warning Area by Saturday...while the ec keeps this
front in far SW Minnesota. Gem is in between keeping Saturday wet and
unsettled with the front nearby. Another aspect is the GFS is much
warmer and nearly caps the atmosphere Saturday/Sunday. Where as
the ec is uncapped and allows for cooler temperatures near the surface.
Therefore...this frontal boundary location will be critical in
terms of rainfall potential and associated surface temperatures and dew points.
Keeping in mind of the more aggressive GFS...temperatures by Sunday may
soar into the 90s with dew points near 70 or higher. This will allow
for heat index values to rise into the middle to upper
90s...especially in SW/wc/SC Minnesota. Current blend of several models
surface temperatures keep these heat index values near heat advisory criteria
by Sunday. Will need to monitor for those working/playing outside.

The upper air flow which is initially west early this week...will
become more SW by the end of the week as the upper low off the
California coast moves inland and across The Rockies. As a strong
upper ridge builds across the southern Continental U.S....and retrogrades to
the west by the weekend...remnants of the upper low will move
across the northern plains/upper Midwest and allow for more
upper level support for widespread lift/precipitation late in the
weekend/early next week.

Next weeks weather will be dependent on how the upper ridge in the SW
Continental U.S. Moves/develops across The Rockies and into the northern
Continental U.S..


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1051 PM CDT Tuesday Jul 7 2015

VFR expected at all terminals through this 24-hour period. Scattered-broken
high decks expected from the early morning hours through tmrw evening...with
some scattered-broken midlvl decks expected late morning through late afternoon.
Winds will remain at or below 10 kts with directions eventually settling
on S by tmrw afternoon. No ceiling/vsby/wx issues. significant weather issues expected.

/Outlook for kmsp/
Thursday...VFR. Winds S 5-10 kts.
Friday...VFR. Winds southeast 5-10 kts.
Sat...mainly VFR. Chance MVFR-IFR in shra/tsra. Winds south-southeast 5-10 kts.


Mpx watches/warnings/advisories...


long term...jlt

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