Porcupine, South Dakota Weather Forecast Discussion

568
FXUS63 KUNR 050827
AFDUNR
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
227 AM MDT Fri Sep 5 2025
.KEY MESSAGES...
- Near freezing temperatures expected over some areas Saturday
  morning.
- Gradual warm-up expected Saturday through early next week, with
  very warm and dry conditions expected.
&&
.DISCUSSION...(Today Through Thursday)
Issued at 206 AM MDT Fri Sep 5 2025
08Z upper level analysis has the Northern Plains under fast
cyclonic flow, with little cloud cover at the moment. At the
surface, cool high pressure resides over the area with west to
northwest winds around 10-15 mph. Temperatures at 2 PM across the
forecast area remain in the 40s to lower 50s.
Cyclonic upper flow remains over the region today, with
unseasonably cool and dry conditions expected. High temperatures
will only be in the 60s to around 70 degrees today. Northwest
winds will become breezy across the SD plains by mid morning, and
remain breezy through late afternoon. Breezy winds will quickly
subside by early evening with very cool air settling over the
area. Several locations will be near freezing late tonight, with
patchy frost expected across much of the area Saturday morning.
Cyclonic upper flow transitions to ridging over the weekend.
After a very chilly start Saturday morning, temperatures will
slowly warm back into the mid 60s to mid 70s Saturday, and into
the 70s to mid 80s by Sunday. Dry conditions continue.
Strong ridging dominates the upper level flow for much of next
week. Dry conditions continue with temperatures above average.
&&
.AVIATION...(For the 06Z TAFS Through 06Z Friday Night)
Issued At 935 PM MDT Thu Sep 4 2025
VFR through period. Northwest winds will pick up tomorrow morning
with gusts of 25 to 35kt possible over the western SD plains.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&
$$
DISCUSSION/KEY MESSAGES...15
AVIATION...Wong

NWS UNR Office Area Forecast Discussion