201
FNUS73 KUNR 171508
FWSUNR

Spot Forecast for Route Four Nine...SD-PRA
National Weather Service Rapid City SD
908 AM MDT Sun Aug 17 2025

Forecast is based on forecast start time of 1000 MDT on August 17.
If conditions become unrepresentative, contact the National Weather
Service.

.DISCUSSION...

Unsettled weather and a moist airmass will remain in place across
much of western SD through Monday. Isolated thunderstorms may
develop over the Black Hills and portions of northeastern Wyoming
this afternoon and evening. Storms may also develop across
southwestern into south central South Dakota this evening. These
storms could produce frequent cloud to ground lightning but also
very heavy downpours. Conditions will become hotter and drier by
the middle of next week.

.REST OF TODAY...

Sky/weather.........Sunny (15-25 percent).
Max temperature.....Around 91.
Min humidity........37 percent.
Wind (20 ft)........Northwest winds around 10 mph shifting to the
                    north late in the afternoon. Gusts up to 16
                    mph.
CWR.................0 percent.
Mixing height.......5300 to 5800 ft agl.
Transport winds.....North 15 to 20 mph.
Smoke dispersal.....Good.

TIME (MDT)      10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........36  32  15  5   3   7   8   13
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0   0   0   0
Temp............79  81  84  87  88  89  90  89
RH..............74  64  54  45  42  39  37  38
20 FT wind dir..NW  NW  NW  NW  N   N   N   N
20 FT wind spd..7   7   7   7   8   8   8   9
20 FT wind gust.10  12  12  14  15  15  16  16
Mix hgt (kft)...1.9 2.4 2.8 3.4 4.0 5.8 5.0 4.8
Transp wind dir.N   N   N   N   N   N   N   N
Transp wind spd.12  13  13  14  14  14  15  16

.TONIGHT...

Sky/weather.........Partly cloudy (25-35 percent) then becoming
                    mostly cloudy (55-65 percent) then becoming
                    mostly clear (15-25 percent). Slight chance of
                    showers and thunderstorms early in the evening,
                    then chance of showers and thunderstorms early
                    in the evening. Slight chance of showers and
                    thunderstorms late in the evening.
Min temperature.....Around 62.
Max humidity........93 percent.
Wind (20 ft)........Northeast winds around 10 mph with gusts to
                    around 17 mph decreasing to northeast around 10
                    mph with gusts to around 14 mph early in the
                    evening, then decreasing to northeast around 10
                    mph with gusts to around 13 mph late in the
                    evening shifting to the east with gusts to
                    around 12 mph overnight shifting to the south
                    shifting to the southwest early in the morning.
                    Gusty and erratic winds expected near
                    thunderstorms in the evening.
CWR.................20 percent.
Mixing height.......400 to 900 ft agl.
Transport winds.....North 15 to 20 mph shifting to the northwest
                    late in the evening, then shifting to the
                    northeast late in the evening shifting to the
                    east overnight shifting to the south.
Smoke dispersal.....Poor.

TIME (MDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........31  59  68  58  52  28  17  18  20  16  13  14
Weather cov.....SCH SCH CHC CHC SCH
Weather type....RW  RW  RW  RW  RW
Tstm cov........SCH SCH CHC CHC SCH
CWR.............20  20  20  20  20  20  20  20  20  20  20  20
Temp............87  84  77  74  72  70  69  68  67  64  64  64
RH..............39  44  58  64  68  73  76  78  81  90  90  90
20 FT wind dir..N   NE  E   NE  N   NE  E   SE  S   S   S   SW
20 FT wind spd..10  9   8   8   7   6   6   6   6   5   5   5
20 FT wind gust.17  15  14  14  13  12  12  10  9   9   9   8
Mix hgt (kft)...3.5 1.3 0.5 0.5 0.4 0.5 0.5 0.4 0.4 0.4 0.4 0.4
Transp wind dir.N   N   NW  NW  N   NE  E   E   S   S   S   SW
Transp wind spd.17  17  15  14  13  12  10  9   9   8   8   8

.MONDAY...

Sky/weather.........Sunny (5-15 percent). Slight chance of showers
                    and thunderstorms early in the afternoon.
                    Chance of showers and thunderstorms late in the
                    afternoon.
Max temperature.....Around 92.
Min humidity........33 percent.
Wind (20 ft)........South winds around 5 mph shifting to the
                    southeast 10 to 15 mph with gusts to around 18
                    mph in the late morning and afternoon. Gusty
                    and erratic winds expected near thunderstorms
                    in the afternoon.
CWR.................20 percent.
Mixing height.......8700 to 9200 ft agl.
Transport winds.....Southwest 10 to 15 mph shifting to the
                    northwest around 20 mph late in the afternoon.
Smoke dispersal.....Good increasing to very good late in the
                    afternoon.

TIME (MDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........18  15  8   3   6   6   5   9   13  17  18  20
Weather cov.....                        SCH SCH SCH CHC CHC CHC
Weather type....                        RW  RW  RW  RW  RW  RW
Tstm cov........                        SCH SCH SCH CHC CHC CHC
CWR.............20  20  20  20  20  20  20  20  20  20  20  20
Temp............62  64  68  75  78  82  86  88  89  89  88  87
RH..............93  87  78  62  54  46  40  36  34  33  34  36
20 FT wind dir..S   S   SE  SE  SE  SE  SE  SE  SE  SE  SE  E
20 FT wind spd..5   5   5   6   6   7   7   8   8   9   10  12
20 FT wind gust.8   8   9   10  12  12  13  14  15  16  17  18
Mix hgt (kft)...0.4 0.7 0.9 1.2 2.4 3.5 4.7 6.2 7.7 9.2 7.2 5.2
Transp wind dir.SW  SW  SW  SW  SW  S   S   SW  SW  W   W   NW
Transp wind spd.8   8   9   9   10  10  12  13  14  15  17  18

$$
Forecaster...DH
Requested by...Justin Bauer
Type of request...WILDFIRE
.TAG 2519978.1/UNR
.DELDT 08/17/25
.FormatterVersion 2.0.0
.EMAIL justin.bauer@bia.gov