318
FNUS75 KRIW 211216
FWSRIW

Spot Forecast for Green River Tunnel DSS...NTSB
National Weather Service Riverton WY
516 AM MST Fri Feb 21 2025

Forecast is based on forecast start time of 0600 MST on February 21.
If conditions become unrepresentative, contact the National Weather
Service

.DISCUSSION...

Patchy fog possible to linger early this Friday morning
dissipating soon after sunrise by 7-8AM. Otherwise, dry conditions
and mostly sunny skies throughout the day. Light westerly winds 5
to 10 mph this morning will increase to 20 to 25 mph gusts by
1-2Pm before diminishing once again after sunset by 6-7PM. Warming
trend starting today and through the weekend with dry conditions
continuing into early next week.

...Thunderstorms imply strong gusty and erratic winds...

.TODAY...

Sky/weather.........Mostly sunny (30-40 percent). Patchy fog early
                    in the morning.
Chance of pcpn......0 percent.
Max temperature.....Around 36.
Min humidity........54 percent.
Min apparent temp...18.
Surface winds (mph).Light winds until 1200, then west 10 to 15 mph
                    with gusts to around 21 mph.
Wind (20 ft)........West winds 7 to 12 mph until 0800, then light
                    until 1200, then west 8 to 12 mph with gusts to
                    around 17 mph.

TIME (MST)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........60  55  50  40  35  25  20  15  10  10  5   5
Weather cov.....PTY
Weather type....FOG
Tstm cov........
Chc of pcpn (%).0   0   0   0   0   0   0   0   0   0   0   0
Temp............25  25  25  26  28  30  33  34  35  36  36  33
RH..............88  84  81  78  68  69  58  58  56  56  59  61
Wind chill (F)..M   M   M   M   M   M   M   M   M   M   M   M
20 FT wind dir..W   W   W   W   W   W   W   W   W   W   W   W
20 FT wind spd..4   4   4   6   6   6   8   9   9   10  12  10
20 FT wind gust.6   6   6   7   10  10  12  13  13  14  17  14
Surface wnd dir.W   W   W   W   W   W   W   W   W   W   W   W
Surface wnd spd.5   5   5   8   8   8   10  11  11  13  15  13
Surface wnd gst.7   7   7   9   12  12  15  16  16  17  21  17

.SATURDAY...

Sky/weather.........Mostly sunny (45-55 percent).
Chance of pcpn......0 percent.
Max temperature.....Around 38.
Min humidity........52 percent.
Min apparent temp...10.
Surface winds (mph).Light winds until 1200, then west 9 to 13 mph.
Wind (20 ft)........West winds 7 to 10 mph until 0800, then light
                    until 1200, then west 7 to 10 mph.

TIME (MST)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........35  40  45  50  50  50  50  55  60  60  60  55
Weather cov.....
Weather type....
Tstm cov........
Chc of pcpn (%).0   0   0   0   0   0   0   0   0   0   0   0
Temp............17  16  19  22  27  32  34  36  38  37  37  37
RH..............73  73  73  65  57  55  54  54  52  59  59  59
Wind chill (F)..M   M   M   M   M   M   M   M   M   M   M   M
20 FT wind dir..SW  SW  SW  SW  W   W   W   W   W   W   W   W
20 FT wind spd..4   3   4   4   5   6   7   8   9   10  10  7
20 FT wind gust.6   4   6   6   6   8   10  12  13  14  14  13
Surface wnd dir.SW  SW  SW  SW  W   W   W   W   W   W   W   W
Surface wnd spd.5   4   5   5   6   8   9   10  11  13  13  9
Surface wnd gst.7   5   7   7   8   10  13  15  16  17  17  16

.FORECAST DAYS 3 THROUGH 5...
.SUNDAY...
Partly cloudy. Lows around 17. Highs in the lower 40s. Light
winds.
.MONDAY...
Partly cloudy. Lows in the lower 30s. Highs in the mid 40s. West
winds around 10 mph.
.TUESDAY...
Partly cloudy. Lows in the upper 20s. Highs in the upper 40s.
Southwest winds around 7 mph.

$$
Forecaster...Lowe
Requested by...NTSB
Type of request...OTHER
.TAG 2503387.0/RIW
.DELDT 02/21/25
.FormatterVersion 2.0.0
.EMAIL roc@ntsb.gov