584
FNUS75 KCYS 181833
FWSCYS

Spot Forecast for Gras Fire...Alliance Fire Department
National Weather Service Cheyenne WY
1233 PM MDT Tue Jun 18 2024

If conditions become unrepresentative, contact the National Weather
Service at (307) 772-2227

.DISCUSSION...

Breezy winds, mostly sunny skies, and low relative humidity
values this afternoon will create near critical red flag
conditions. Minimum humidity by 1500 will approach the upper
teens, and northwest winds of 15 to 22 mph will be expected.
A low chance of a brief rain shower this afternoon may create
gusty and erratic wind gusts in excess of 30-35mph. Very good
overnight humidity recovery is expected, with cool and dry
weather conditions through the night. A wind shift from the
northwest to northeast is expected by 2100 this evening, with
sustained winds of 10-20mph.

.REST OF TODAY...

Sky/weather.........Sunny (15-25 percent).
CWR.................2 percent.
LAL.................1.
Max temperature.....Around 69-71.
Min humidity........17-21 percent.
Wind (20 ft)........Northwest winds 12 to 17 mph.
Mixing height.......8100 ft AGL.
Transport winds.....Northwest 15 to 22 mph.
Smoke dispersal.....Good (99700 knot-ft) early in the morning
                    increasing to very good (106200 knot-ft) in the
                    afternoon.
Haines Index........3 or very low potential for large plume
                    dominated fire growth.

TIME (MDT)      1PM 2PM 3PM 4PM 5PM
Sky (%).........17  14  15  18  28
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0
LAL.............1   1   1   1   1
Temp............67  68  69  70  70
RH..............23  22  22  20  20
20 FT wind dir..NW  NW  NW  NW  N
20 FT wind spd..16  15  14  13  12
20 FT wind gust.30  26  24  23  22
Mix hgt (kft)...5.6 6.2 6.8 7.6 8.1
Transp wind dir.NW  NW  NW  NW  N
Transp wind spd.21  18  17  16  15
Haines index....3   3   3   3   3
SDspl kt-ft/1000100 100 103 106 106

.TONIGHT...

Sky/weather.........Partly cloudy (30-40 percent).
CWR.................3 percent.
LAL.................1.
Min temperature.....Around 44-46.
Max humidity........75 percent.
Wind (20 ft)........North winds 12 to 13 mph shifting to the
                    northeast 9 to 13 mph late in the evening.
Mixing height.......900 ft AGL.
Transport winds.....North around 15 mph shifting to the east 13 to
                    17 mph late in the evening.
Smoke dispersal..... very good (105800 knot-ft) early in the
                    evening decreasing to poor (9900 knot-ft) late
                    in the night.
Haines Index........3 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 (%).........29  28  26  24  26  34  34  29  28  29  35  46
Weather cov.....
Weather type....
Tstm cov........
CWR.............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............68  65  62  58  56  54  52  50  49  47  47  46
RH..............23  27  32  40  47  52  59  63  68  74  74  73
20 FT wind dir..N   N   N   N   NE  NE  NE  NE  NE  NE  NE  NE
20 FT wind spd..12  12  12  13  13  13  13  12  12  10  9   9
20 FT wind gust.22  22  22  23  23  24  24  22  20  18  17  17
Mix hgt (kft)...8.1 7.3 5.9 4.5 3.3 2.4 1.6 1.2 1.0 1.0 0.9 1.0
Transp wind dir.N   N   NE  E   E   E   SE  E   E   E   E   E
Transp wind spd.15  15  15  16  16  16  16  15  14  13  13  17
Haines index....3   3   3   3   3   3   3   3   3   3   3   3
SDspl kt-ft/1000106 94  77  63  47  33  23  15  12  11  10  15

$$
Forecaster...Wills
Requested by...Nick Hinman
Type of request...WILDFIRE
.TAG 2416364.0/CYS
.DELDT 06/18/24
.FormatterVersion 2.0.0
.EMAIL nhinman@cityofalliance.net