Area Forecast Discussion
Issued by NWS Rapid City, SD

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FXUS63 KUNR 232320

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
520 PM MDT Sun Oct 23 2016

.SHORT TERM...(This Evening Through Monday Night)
Issued at 253 PM MDT Sun Oct 23 2016

Current surface analysis shows high pressure centered over the
Northern Plains. Upper level analysis continues to show broad
ridge axis centered over the central US. Skies are mostly sunny
across the area with temps in the mid 50s to lower 60s. Winds are
mostly light, switching to the south and southeast over western
portions of the cwa as high begins to move east of the area.

Mostly quiet weather will continue into the early part of the week
as ridge remains over the region. Skies will be partly cloudy in
general tonight with lows in the mid 30s to mid 40s. Low clouds to
the north and east of the cwa will sink south into at least parts of
northwest SD overnight, with some patchy fog possible late
tonight/Monday morning.

Frontal boundary to the south and west of the region will slide
northeast into the Black Hills area as a warm front on Monday. The
warmest temperatures will be from northeast WY to southwest SD.
Highs will generally range from the upper 50s over far northwest SD
to the mid 70s over far southwest SD. Clouds will increase, with
mostly cloudy skies across much of the area by late afternoon. Skies
will remain mostly cloudy Monday night as shortwave energy slides
across the plains. Chances for pcpn should stay south and east of
the forecast area, with lows in the 40s.

.LONG TERM...(Tuesday Through Sunday)
Issued at 253 PM MDT Sun Oct 23 2016

Eastern pac troughing will persist through the period as fast
westerly disturbed flow over the northern pac supports trough re-
loading there. This will continue to support downstream mean
ridging over the northern Rockies into the plains. Flow will
remain progressive with periodic disturbances ejecting out of the
persistent trough. This will support mild weather in the period,
esp ahead of each impulse in sw flow, with 60s-70s for highs and
30s/40s/50s for lows. Mean storm track looks to remain just north
of the fa, which supports dry weather locally. As cold air
continues to build over the high latitudes per seasonal trends,
flow will likely become more amplified. This trend is also
indicated in the gfs/ecmwf/cmc toward the end of the period with
stronger/deeper troughs progged in the northern and southern
streams. A stronger/deeper trough will advect through the region
thur with a cold front Friday night. Strong waa ahead of this
system may support near record to record highs Thursday, along
with the first chances for precip this week Friday night. The only
concern in the period will be fire weather with very dry westerly
flow and potentially breezy conds at times.


.AVIATION...(For the 00Z TAFS Through 00Z Monday Evening)
Issued At 516 PM MDT Sun Oct 23 2016

Fog combined with some stratus may bring MVFR/IFR conditions to
portions of northwest into central SD overnight. Otherwise, expect
VFR conditions through the period.




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