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000
FNUS75 KTFX 111148
FWSTFX

Spot Forecast for Middleman 40...USFS
National Weather Service Great Falls MT
548 AM MDT Thu Apr 11 2024

Forecast is based on ignition time of 0800 MDT on April 12.
If conditions become unrepresentative...contact the National Weather
Service.

.DISCUSSION...

A shift to a more southwesterly flow aloft on Friday will bring in
a chance of showers and thunderstorms by 1500 MDT. These storms
will likely not produce much rain, but they could produce erratic
wind gusts to 40 mph at times through the late afternoon and early
evening hours. Humidity should fall from the upper 30s around noon
into the lower 30s between 1500 MDT and 1700 MDT or so. Shower and
thunderstorm activity should diminish overnight, but there will be
another chance for showers Saturday afternoon, but with slightly
less of a chance of thunderstorms. However, prevailing winds will
become breezy out of the southwest to west during the afternoon.

.FRIDAY...

Sky/weather.........Mostly sunny (45-55 percent). Chance of rain
                    showers and slight chance of thunderstorms in
                    the afternoon.
CWR.................5 percent.
LAL.................1 until 1400, then 2.
Max temperature.....68-73.
Min humidity........27-32 percent.
Wind (20 ft)........
 Slope/valley.......Southeast winds around 10 mph shifting to the
                    southwest late in the afternoon. Gusty and
                    erratic winds expected near thunderstorms in
                    the afternoon.
Mixing height.......7500 ft AGL.
Transport winds.....Southeast around 10 mph shifting to the
                    southwest early in the afternoon, then shifting
                    to the west around 20 mph late in the
                    afternoon.
Haines Index........3 or very low potential for large plume
                    dominated fire growth.

TIME (MDT)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........53  38  44  40  59  59  59  59  59  59
Weather cov.....                SCH SCH CHC CHC CHC CHC
Weather type....                RW  RW  RW  RW  RW  RW
Tstm cov........                        SCH SCH SCH SCH
CWR.............0   0   0   0   10  10  10  10  10  10
LAL.............1   1   1   1   1   1   2   2   2   2
Temp............45  48  55  59  62  65  68  69  70  69
RH..............59  54  45  41  38  35  33  32  31  31
20 FT wind dir..SE  SE  SE  SE  SE  SE  SE  SW  SW  SW
20 FT wind spd..10  10  10  10  10  10  10  15  15  15
20 FT wind gust.15  15  15  15  15  15  15  20  20  20
Mix hgt (kft)...0.5 1.0 1.5 2.0 3.0 4.5 6.5 7.5 7.0 5.5
Transp wind dir.SE  SE  SE  S   SW  SW  SW  W   W   W
Transp wind spd.10  10  10  10  10  15  20  20  20  20
Haines index....3   3   3   3   3   3   3   3   3   3

.FRIDAY NIGHT...

Sky/weather.........Mostly cloudy (60-70 percent). Chance of rain
                    showers and slight chance of thunderstorms in
                    the evening, then slight chance of rain showers
                    overnight.
CWR.................5 percent.
LAL.................2 until 2200, then 1.
Min temperature.....41-46.
Max humidity........77-82 percent.
Wind (20 ft)........
 Slope/valley.......West winds around 10 mph shifting to the east
                    late in the evening, then shifting to the south
                    overnight. Gusty and erratic winds expected
                    near thunderstorms in the evening.
Mixing height.......0 ft AGL.
Transport winds.....Southwest around 15 mph shifting to the
                    southeast 5 to 10 mph early in the evening,
                    then becoming around 10 mph overnight shifting
                    to the south early in the morning.
Haines Index........

TIME (MDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........61  61  61  72  72  72  73  73  73  72  72  72
Weather cov.....CHC CHC CHC CHC SCH SCH SCH SCH SCH SCH SCH SCH
Weather type....RW  RW  RW  RW  RW  RW  RW  RW  RW  RW  RW  RW
Tstm cov........SCH SCH SCH SCH
CWR.............10  10  10  10  10  10  10  10  10  10  10  10
LAL.............2   2   2   2   1   1   1   1   1   1   1   1
Temp............68  63  58  54  52  50  49  48  46  46  45  44
RH..............34  42  51  59  64  66  68  70  72  74  77  80
20 FT wind dir..W   W   W   E   E   E   SE  SE  SE  S   S   S
20 FT wind spd..10  10  10  5   5   5   5   5   5   5   5   5
20 FT wind gust.15  15  15  10  10  10  10  10  10  10  10  10
Mix hgt (kft)...4.0 3.0 1.5 0.5 0.1 0.5 0.5 0.5 0.5 0.5 0.5 0.5
Transp wind dir.W   SW  S   SE  SE  E   E   E   SE  SE  SE  S
Transp wind spd.15  15  10  5   5   5   10  10  10  10  10  5
Haines index....3   3   3   M   M   M   M   M   M   M   M   M

.SATURDAY...

Sky/weather.........Partly sunny (60-70 percent). Chance of rain in
                    the afternoon.
CWR.................5 percent.
LAL.................1.
Max temperature.....68-73.
Min humidity........28-33 percent.
Wind (20 ft)........
 Slope/valley.......South winds around 5 mph shifting to the west
                    10 to 15 mph in the afternoon.
Mixing height.......6500 ft AGL.
Transport winds.....South 5 to 10 mph shifting to the west 10 to 15
                    mph in the late morning and early afternoon,
                    then increasing to around 20 mph late in the
                    afternoon.
Haines Index........3 or very low potential for large plume
                    dominated fire growth early in the morning.

TIME (MDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........77  77  77  58  58  58  50  50  50  50  50  50
Weather cov.....                        CHC CHC CHC CHC CHC CHC
Weather type....                        RN  RN  RN  RN  RN  RN
Tstm cov........
CWR.............10  10  10  10  10  10  10  10  10  10  10  10
LAL.............1   1   1   1   1   1   1   1   1   1   1   1
Temp............44  45  47  49  53  58  62  65  67  69  70  70
RH..............81  79  75  69  62  54  47  42  38  36  33  32
20 FT wind dir..S   S   S   S   S   S   SW  SW  SW  W   W   W
20 FT wind spd..5   5   5   5   5   5   10  10  10  15  15  15
20 FT wind gust.10  10  10  10  10  10  15  15  15  20  20  20
Mix hgt (kft)...0.5 0.5 1.0 1.0 2.0 3.0 4.0 5.0 6.0 6.5 6.5 6.0
Transp wind dir.S   S   SW  SW  SW  W   W   W   W   W   W   W
Transp wind spd.5   5   5   10  10  10  15  15  20  20  20  20
Haines index....M   M   3   3   3   3   3   3   3   3   3   3

$$
Forecaster...Coulston
Requested by...Lewis Tafelmeyer
Type of request...PRESCRIBED
.TAG 2410342.0/TFX
.DELDT 04/11/24
.FormatterVersion 2.0.0
.EMAIL lewis.tafelmeyer@usda.gov, tfx.ops@noaa.gov