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fxus63 kunr 281716 
afdunr

Area forecast discussion for western South Dakota and northeastern Wyoming
National Weather Service Rapid City South Dakota
1116 am MDT sun may 28 2017

Discussion...(today through saturday)
issued at 205 am MDT sun may 28 2017

Closed low over southern Canada will continue to support
unsettled weather today as yet another impulse will advect through
the region. This impulse will be stronger than yesterday's wave
given jet support aloft, supporting a little better coverage of
afternoon convection. Lead forcing on the front side of the
impulse/jet may support a few isolated showers this morning, with
diurnal heating under the cold aloft helping to support sct
shra/ts this afternoon. Best chance for precip will be in/near the
Black Hills and NE Wyoming given better cape and instability there.
Shra/ts will likely support gusty winds given high based nature
and inverted v profiles. Shra activity will wane and shift southeast this
evening. Otherwise, it will be windy today (esp northwest sd) as linked
strong flow will be present with steep ll lapse rates.

Dry weather can be expected Mon-tues and most places Wed, with a
slow warming trend expected under shortwave ridging. Weak impulse
will pass through the region Wed with convection possibly
developing over the bh in the afternoon. This will all hinge on
the amount of ll moisture per return flow and degree of capping
aloft. Mean toughing will become established over the northwest Continental U.S.
Toward the middle of the week with unsettled flow re-developing
over the region per impulse laden west-southwest flow. This will support an
uptick in precip chances late in the week. However, forecast
models continue to vary sig on exact details per the
evolution/progression of upper level flow given blocking potential
over much of Canada. Friday continues to be progged as the best
day for precip chances given strong consensus for an advecting
shortwave trough with decent moisture and resulting cape. Slow
warming trend will continue through the end of the week with
mainly seasonal temps.

&&

Aviation...(for the 18z tafs through 18z monday)
issued at 1112 am MDT sun may 28 2017

Mainly VFR conditions are expected today. Some MVFR conditions
will be possible near showers and thunderstorms. A few storms may
be strong to severe. Northwest winds will be breezy this
afternoon, especially across northwestern South Dakota.



&&

Unr watches/warnings/advisories...
South Dakota...none.
Wyoming...none.
&&

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