Text Products for FWS Issued by RIW

Spot Forecast
Issued by NWS Riverton, WY
Versions: 1 2 3 4 5 6 7 8 9
000
FNUS75 KRIW 171408
FWSRIW

Spot Forecast for Star Valley Front 2B-8...USFS BTNF
National Weather Service Riverton WY
808 AM MDT Wed Apr 17 2024

Forecast is based on ignition time of 0800 MDT on April 17.
If conditions become unrepresentative, contact the National Weather
Service

.DISCUSSION...

Scattered snow showers this morning will be intermittent and light
with little to no accumulation expected. After 1200, temperatures will
warm to the upper 30s and showers will become rain, with snow flakes
mixing in at times. Winds will mostly remain light (less than 10 mph)
from the west, but between 1400 and 2000 will turn northwesterly and may
gust as high as 15 to 18 mph. Chances of precipitation decrease after 1800
and especially after sunset. Overnight, light winds and clearing skies are
expected. Thursday will be mostly sunny and dry with light west to
northwest winds.

...Thunderstorms imply strong gusty and erratic winds...
...Haines index is high level haines both day and night...

.REST OF TODAY...

Sky/weather.........Mostly cloudy (75-85 percent) then becoming
                    mostly sunny (40-50 percent) between 1200 and
                    1400. 30 to 40 percent chance of snow showers
                    until 1200, then 20 percent chance of rain and
                    snow showers until 1800.
CWR.................15 percent decreasing to 1 percent after 1200.
Chance of pcpn......40 percent.
LAL.................1.
Max temperature.....Around 41.
Min humidity........48 percent.
Wind (20 ft)........Light west winds 6 to 11 mph until 1600 to 1700
                    then shifting to the northwest.
Ridgetop wind.......West 10 to 15 mph shifting to the northwest
                    around 20 mph between 1600 and 1700.
Mixing height.......1600 ft AGL increasing to 4600 ft AGL in the
                    afternoon.
Transport winds.....West 10 to 14 mph increasing to 22 to 23 mph in
                    the afternoon.
Smoke dispersal.....Poor (6500 knot-ft) early in the morning
                    increasing to good (92900 knot-ft) in the
                    afternoon after 1400.
Haines Index........2 or very low potential for large plume
                    dominated fire growth.

TIME (MDT)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........90  85  80  75  70  44  42  43  44  48
Weather cov.....CHC CHC CHC CHC SCH SCH SCH SCH SCH CHC
Weather type....SW  SW  SW  SW  SW  SW  SW  SW  SW  SW
Tstm cov........
CWR.............20  20  20  20  0   0   0   0   0   0
Chc of pcpn (%).40  30  30  30  20  20  20  20  20  30
LAL.............1   1   1   1   1   1   1   1   1   1
Temp............32  33  35  37  39  40  40  41  40  40
RH..............75  74  68  61  54  53  52  52  52  53
20 FT wind dir..SW  SW  W   W   W   W   W   W   NW  NW
20 FT wind spd..4   6   7   8   9   10  11  11  11  11
20 FT wind gust.10  12  13  14  16  16  16  14  14  14
Ridge wind dir..SW  W   W   W   W   W   W   NW  NW  NW
Ridge wind spd..10  15  15  15  15  15  15  20  20  20
Mix hgt (kft)...0.7 1.6 1.6 1.6 3.9 3.9 3.9 4.6 4.6 4.6
Transp wind dir.W   W   W   W   W   W   W   W   W   W
Transp wind spd.10  14  14  14  22  22  22  23  23  23
Haines index....2   2   2   2   2   2   2   2   2   2
SDspl kt-ft/10007   20  20  20  74  74  74  93  93  93

.TONIGHT...

Sky/weather.........Mostly cloudy (45-55 percent) then becoming
                    partly cloudy (35-45 percent). 30 percent chance
                    of rain and snow showers between 1800 and 2100 then
                    10 percent chance of snow showers after 2100.
CWR.................0 percent.
Chance of pcpn......30 percent.
LAL.................1.
Min temperature.....Around 22.
Max humidity........85 percent.
Wind (20 ft)........Northwest winds 6 to 9 mph early in the evening
                    becoming light after sunset.
Ridgetop wind.......Northwest around 15 mph shifting to the
                    northeast 5 to 10 mph in the late evening and
                    overnight, then shifting to the east after 0300.
Mixing height.......3900 ft AGL decreasing to 600 ft AGL in the
                    late evening and overnight.
Transport winds.....West around 20 mph becoming northwest 7 to 8
                    mph in the late evening and overnight, then
                    shifting to the south around 9 mph after 0300.
Smoke dispersal.....Good (65800 knot-ft) early in the evening
                    decreasing to poor (3300 knot-ft) late in the
                    night.
Haines Index........2 or very low potential for large plume
                    dominated fire growth.

TIME (MDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........52  52  52  52  50  49  47  42  37  31  29  27
Weather cov.....CHC CHC SCH
Weather type....SW  SW  SW
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   0   0   0   0
Chc of pcpn (%).40  30  20  10  10  10  10  10  10  0   0   0
LAL.............1   1   1   1   1   1   1   1   1   1   1   1
Temp............40  38  36  34  32  31  30  28  27  25  24  24
RH..............55  60  66  72  77  80  83  85  85  85  84  82
20 FT wind dir..NW  N   N   N   N   NE  NE  NE  E   E   E   E
20 FT wind spd..9   6   4   2   1   2   3   3   4   4   4   3
20 FT wind gust.14  10  6
Ridge wind dir..NW  NW  NW  N   N   N   NE  NE  NE  E   E   E
Ridge wind spd..15  15  15  5   5   5   10  10  10  10  10  10
Mix hgt (kft)...3.9 3.9 3.9 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6
Transp wind dir.W   W   W   NW  NW  NW  NW  NW  NW  S   S   S
Transp wind spd.20  20  20  7   7   7   8   8   8   9   9   9
Haines index....2   2   2   2   2   2   2   2   2   2   2   2
SDspl kt-ft/100066  66  66  3   3   3   4   4   4   5   5   5

.THURSDAY...

Sky/weather.........Mostly sunny (25-35 percent).
CWR.................0 percent.
Chance of pcpn......0 percent.
LAL.................1.
Max temperature.....Around 43.
Min humidity........38 percent.
Wind (20 ft)........Light winds becoming northwest 6 to 7 mph late
                    in the afternoon.
Ridgetop wind.......Northeast around 5 mph shifting to the west in
                    the late morning and early afternoon, then
                    increasing to northwest around 15 mph late in
                    the afternoon.
Mixing height.......500 ft AGL increasing to 5100 ft AGL.
Transport winds.....South around 7 mph shifting to the north late
                    in the morning, then shifting to the west 8 to
                    13 mph in the afternoon.
Smoke dispersal.....Poor (3300 knot-ft) early in the morning
                    increasing to fair (55600 knot-ft) in the
                    afternoon.
Haines Index........2 or very low potential for large plume
                    dominated fire growth.

TIME (MDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........25  21  17  13  17  21  26  31  37  42  36  30
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   0   0   0   0
Chc of pcpn (%).0   0   0   0   0   0   0   0   0   0   0   0
LAL.............1   1   1   1   1   1   1   1   1   1   1   1
Temp............23  24  26  27  30  33  36  37  38  40  40  40
RH..............80  78  75  71  64  57  51  47  46  45  45  46
20 FT wind dir..E   NE  NW  W   W   SW  S   SW  W   NW  NW  NW
20 FT wind spd..3   3   3   3   2   1   1   2   4   6   6   7
20 FT wind gust.                    2   2   5   6   8   8   8
Ridge wind dir..NE  NE  NE  W   W   W   W   W   W   NW  NW  NW
Ridge wind spd..5   5   5   5   5   5   5   5   5   15  15  15
Mix hgt (kft)...0.5 0.5 0.5 2.0 2.0 2.0 4.7 4.7 4.7 5.1 5.1 5.1
Transp wind dir.S   S   S   N   N   N   W   W   W   W   W   W
Transp wind spd.7   7   7   7   7   7   8   8   8   13  13  13
Haines index....2   2   2   2   2   2   2   2   2   2   2   2
SDspl kt-ft/10003   3   3   12  12  12  33  33  33  56  56  56

.FORECAST DAYS 3 THROUGH 5...
.FRIDAY...
Mostly clear. Lows in the lower 20s. Highs around 50. Light
winds.
.SATURDAY...
Partly cloudy. Slight chance of showers. Lows in the upper 20s.
Highs in the lower 50s. South winds around 6 mph.
.SUNDAY...
Partly cloudy. Slight chance of showers. Lows in the upper 20s.
Highs in the mid 50s. Southwest winds around 8 mph.

$$
Forecaster...Hensley
Requested by...Michael McEwen
Type of request...PRESCRIBED
.TAG 2411218.0/RIW
.DELDT 04/17/24
.FormatterVersion 2.0.0
.EMAIL michael.mcewen@usda.gov
National Weather Service Weather Forecast Office
