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Area forecast discussion 
National Weather Service Sioux Falls South Dakota
1017 am CDT Monday Jul 6 2015

Short term...(today and tonight)
issued at 346 am CDT Monday Jul 6 2015

The frontal boundary which has been pushing across the area
overnight is moving a little faster than models portrayed it...and
thunderstorms are now confined to our far eastern Minnesota and
eastern Iowa zones...with Post frontal showers extending back
through the remainder of the County Warning Area. Went ahead and cancelled the
western extent of our Flash Flood Watch with showers lightening up.
Dependent on trends through the morning...may be able to cancel the
remainder of the watch before 15z as currently scheduled.
Otherwise...will see a downward trend in the showers/thunderstorms
from west to east through the day...with decreasing clouds by later
in the afternoon. It will be a breezy day with cold air advection
and good mixing...and temperatures will be a good 15 degrees cooler
than yesterday with highs lower to middle 70s.

Surface high pressure begins to build into the region tonight...and
with clearing skies and a light northerly surface flow it will be a
cool night with lows in the lower to middle 50s.

Long term...(tuesday through sunday)
issued at 346 am CDT Monday Jul 6 2015

Quiet and cool conditions expected for middle week as surface ridge
drifts east through the region. Skies Tuesday/Tuesday night should
generally be free of clouds...but unfortunately trajectories aloft
may bring the smoke from Canadian fires back into the region. The
hazy sky...combined with light winds...a relatively cool air mass
with 850mb temperatures only a few degrees either side of 10c...and wetter
ground than we have seen of late...should keep highs in the lower to
middle 70s most areas Tuesday and Wednesday.

Pattern change still on track for the end of the week into next
weekend...with upper ridge building over the southeast Continental U.S. And
more of a southwesterly flow aloft developing over our area. Pattern
is a little more little to quibble with over the low
chance probability of precipitation scattered throughout the longer range. Pattern change
will allow warmer...more seasonable temperatures to spread back into
the region...with 80s likely Friday through Sunday...and even some
90s possible in parts of the area again on Saturday. Transition to
westerly and eventually southwesterly flow should also shunt smoke
off to our east for the latter part of this week. May have to watch
early next week again models pointing to upper ridge
axis building northward through The Rockies again by early Monday.


Aviation...(updated for the 12z tafs through 12z tuesday)
issued at 1017 am CDT Monday Jul 6 2015

Update to note that the northerly low level flow has brought
another fetch of smoke over the area and is reducing visibilities
to 1-3sm over the northern part of the area. Expect this to
improve to 3-5sm by 18z and become a little more general and have
accounted for this in the Hon and fsd taf forecasts. Otherwise
showers continue to decrease to the southeast as forecast
earlier. Ceilings 1-3k feet over the western and northern parts of
the area will improve to VFR by 20z. A few surface gusts around
25 knots from the north through 07/00z. VFR expected 07/00z-12z.


Fsd watches/warnings/advisories...
South Dakota...none.


long term...jh

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