Area Forecast Discussion
Issued by NWS Rapid City, SD

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FXUS63 KUNR 270801
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
201 AM MDT MON JUN 27 2016

.SHORT TERM...(Today Through Tuesday Night)
Issued at 157 AM MDT Mon Jun 27 2016

West-northwest flow is over the northern plains as upper ridge
builds over the western CONUS. A weak wave is producing some
showers across northwestern SD/southwestern ND. Surface winds are
northeasterly behind a cool front, and surface high pressure is
sliding into the region. Temperatures at 2 AM are in the mid 50s
to mid 60s.

Upper ridge will shift eastward over the Rockies today. Easterly
winds will advect moist air into the area, and with 50s dewpoints
across southwestern SD, instability may allow for a few storms to
develop there and also over the Black Hills. Upper forcing is
lacking, however. Highs today will be in the lower 80s, with 70s in
the Black Hills. Winds turn southeasterly tonight, and weak theta-e
advection develops across parts of the CWA. Some weak showers/storms
are possible tonight, but generally conditions will remain dry. Lows
will be in the 50s.

On Tuesday, a shortwave will move over the ridge into the region,
with a weak jet streak developing over southwestern SD. More
moisture will push into the region as southeast winds become breezy.
MLCAPE will increase to 1000-2000 J/kg across the CWA, and with 0-6km
shear around 50 kts, conditions are supportive of severe
thunderstorms. Hi-res convective models indicate cells forming
over northeastern WY, strengthening and possibly becoming an MCS
as they move east-southeastward. Thunderstorms will gradually move
out of the CWA Tuesday night. Highs Tuesday will be in the 80s,
with lows near 60.

.LONG TERM...(Wednesday Through Sunday)
Issued at 157 AM MDT Mon Jun 27 2016

Upper ridge axis will remain to our west into the weekend with
generally W/NW flow through the nrn plains. Looks to be a fairly
active extended period with several upper impulses moving through
the flow aloft, with the strongest in the extended period arriving
Friday into early Saturday. The active flow should keep temps near
average levels into the weekend. By the end of the weekend/early
next week, the upper ridge will finally move into the nrn plains
and result in warmer temps and less chances for storms.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Tuesday Morning)
Issued At 157 AM MDT Mon Jun 27 2016

Areas of smoke from fires over the Bear Lodge mountains
and northern Black Hills will bring local MVFR/IFR visibility to the
Black Hills area at times. Isolated TSRA chances will continue today
across far srn SD, with sct TSRA possible in the Black Hills this
aftn/eve. MVFR/IFR conditions in heavier storms. Otherwise, VFR
conditions expected through the period.

&&

.UNR Watches/Warnings/Advisories...
SD...None.
WY...None.
&&

$$

SHORT TERM...Pojorlie
LONG TERM...Johnson
AVIATION...Johnson



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