183
FNUS75 KTFX 050130
FWSTFX

Spot Forecast for Black Diamond...USFS
National Weather Service Great Falls MT
730 PM MDT Mon May 4 2026

Forecast is based on ignition time of 2000 MDT on May 04.
If conditions become unrepresentative...contact the National Weather
Service.

.DISCUSSION...

A secondary trough passage will maintain variable cloudiness,
widely scattered rain and snow showers, and northerly breezes for
the next 24 to 36 hours. Westerly breezes will bring a return to
warmer and drier conditions on Wednesday before periods of
scattered showers and some thunderstorms develop Wednesday night
and more or less continue into the weekend.

.REST OF TONIGHT...

Sky/weather.........Mostly cloudy (50-70 percent). Slight chance of
                    rain showers in the evening, then a slight chance of
                    snow showers overnight.
CWR.................Less than 10 percent.
Chance of thunder...Less than 10 percent.
Min temperature.....28-33.
Max humidity........67-72 percent.
Wind (20 ft)........
 Slope/valley.......Northeast winds 5 to 10 mph.
Mixing height.......1000 ft AGL.
Transport winds.....Northeast 10 to 15 mph.

TIME (MDT)      8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........78  66  65  56  48  49  57  59  64  68
Weather cov.....SCH SCH SCH SCH SCH     SCH SCH SCH SCH
Weather type....RN  RS  RS  SN  SN      SN  SN  SN  SN
Tstm cov........
CWR.............10  10  10  10  10  10  10  10  10  10
Chc of thdr (%).0   0   0   0   0   0   0   0   0   0
Temp............46  43  41  39  39  37  35  34  32  32
RH..............49  58  59  57  51  51  51  57  64  64
20 FT wind dir..NE  NE  NE  NE  NE  NE  NE  NE  NE  NE
20 FT wind spd..10  10  10  10  10  10  5   5   5   5
20 FT wind gust.15  15  15  15  15      10  10  10  10
Mix hgt (kft)...3.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
Transp wind dir.NE  NE  NE  NE  NE  E   NE  E   NE  NE
Transp wind spd.15  15  15  15  15  15  15  10  10  15

.TUESDAY...

Sky/weather.........Partly sunny (50-70 percent). Chance of snow
                    showers in the morning, then slight chance of snow
                    showers in the afternoon.
CWR.................Less than 10 percent.
Chance of thunder...Less than 10 percent.
Max temperature.....42-47.
Min humidity........27-32 percent.
Wind (20 ft)........
 Slope/valley.......Northeast winds 5 to 15 mph.
Mixing height.......7000 ft AGL.
Transport winds.....Northeast 15 to 20 mph.

TIME (MDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........76  83  68  76  73  62  53  53  57  57  55  44
Weather cov.....CHC CHC CHC CHC CHC SCH SCH SCH SCH SCH SCH SCH
Weather type....SN  SN  SN  SN  SN  SN  SN  SN  SN  SN  SN  SN
Tstm cov........
CWR.............10  10  10  10  10  10  10  10  10  10  10  10
Chc of thdr (%).0   0   0   0   0   0   10  10  10  10  10  10
Temp............31  31  30  33  36  37  39  41  41  42  43  42
RH..............70  70  66  61  47  44  40  37  34  34  32  32
20 FT wind dir..NE  NE  NE  NE  NE  NE  NE  NE  NE  NE  NE  NE
20 FT wind spd..5   5   5   10  10  10  10  10  10  10  10  10
20 FT wind gust.10  10  10  15  15  15  20  20  20  20  20  20
Mix hgt (kft)...1.5 2.5 2.5 3.5 4.5 5.0 6.0 6.5 6.0 6.5 6.5 7.0
Transp wind dir.NE  NE  NE  NE  NE  N   N   N   N   N   N   N
Transp wind spd.15  15  15  15  15  15  15  15  20  20  20  20

.TUESDAY NIGHT...

Sky/weather.........Mostly clear (20-30 percent). Slight chance of
                    snow showers early in the evening.
CWR.................Less than 10 percent.
Chance of thunder...Less than 10 percent.
Min temperature.....22-27.
Max humidity........62-67 percent.
Wind (20 ft)........
 Slope/valley.......Northeast winds 5 to 10 mph in the evening
                    becoming light.
Mixing height.......500 ft AGL.
Transport winds.....North 15 to 20 mph becoming northeast 5 to 10
                    mph in the late evening and overnight, then
                    shifting to the west after 3 am.

TIME (MDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........37  32  28  23  19  15  12  14  15  16  13  10
Weather cov.....SCH SCH SCH
Weather type....SN  SN  SN
Tstm cov........
CWR.............10  10  10  10  10  10  0   0   0   0   0   0
Chc of thdr (%).0   0   0   0   0   0   0   0   0   0   0   0
Temp............42  41  37  34  33  30  30  28  27  26  26  25
RH..............32  33  39  47  51  56  58  59  61  64  65  67
20 FT wind dir..NE  NE  NE  NE  NE  NE  NE  N   W   W   W   SW
20 FT wind spd..10  10  10  5   5   5   5   0   0   0   0   0
20 FT wind gust.20  15  15  10  10          5   5   5   5   5
Mix hgt (kft)...6.0 4.5 3.0 2.0 1.5 1.0 0.5 0.5 0.5 0.5 0.5 0.5
Transp wind dir.N   N   N   NE  NE  NE  NE  NE  N   W   W   W
Transp wind spd.15  20  15  10  10  5   5   5   5   5   5   5

$$
Forecaster...Greely
Requested by...Jarel Kurtz
Type of request...PRESCRIBED
.TAG 2612468.3/TFX
.DELDT 05/04/26
.FormatterVersion 2.0.0
.EMAIL jarel.kurtz@usda.gov, tfx.ops@noaa.gov