550
FNUS75 KTWC 200120
FWSTWC

Spot Forecast for Catalina Piles...USFS
National Weather Service Tucson AZ
620 PM MST Wed Nov 19 2025

Forecast is based on ignition time of 0800 MST on November 20.

.DISCUSSION...Two weather systems will be the main focus for the
forecast period. The first weather system will begin to exit
today, resulting in morning rain showers mixed with snow showers.
There are slight chances for an embedded thunderstorm in the
morning. Snow levels will bottom out to 6500 feet this early
morning and slowly climb up to 7500 feet by mid-day. Rain showers
and snow showers chances will dramatically decrease after noon
today. Winds will be southwesterly up to 11 mph and becoming light
in the overnight period. The second weather system will impact
the region late on Friday, bringing more chances for rain showers
and snow showers into the weekend.

.THURSDAY...

Sky/weather.........Mostly cloudy then becoming mostly sunny. Rain
                    showers, mixed with snow showers, and slight
                    chance for thunderstorm in the morning,
                    then decreasing chances after 1200 hours.
Chance of pcpn......70 percent decreasing to 0 percent.
Max temperature.....39-42 degrees.
Min humidity........85-88 percent.
20-foot winds.......Southwest winds 6 to 11 mph in the morning becoming
                    west after 1200 hours Gusty and erratic
                    winds expected near thunderstorms early in the
                    morning.
Mixing height.......300 ft AGL.
Transport winds.....West 8 to 14 knots.

TIME (MST)      8 AM      11 AM     2 PM      5 PM
Sky (%).........78        83        76        39
Weather cov.....LIKELY    CHANCE
Weather type....SNSHWR    SNSHWR    NONE      NONE
Tstm cov........
CWR.............60        30        0         0
Temp............36        37        38        36
RH..............94        100       93        89
20 FT wind......SW 8G13   SW-W 8G13 W 7G12    W 5G8
Mix hgt (ft)....BLW100    BLW100    300       BLW100
Transport wind..SW 14     W 13      W 11      W 8

.THURSDAY NIGHT...

Sky/weather.........Partly cloudy then becoming mostly cloudy.
Chance of pcpn......0 percent.
Min temperature.....31-34 degrees.
Max humidity........97-100 percent.
20-foot winds.......West-southwest winds 5 to 9 mph shifting to
                    drainage flow at 2 to 6 mph after midnight.
Mixing height.......100 ft AGL.
Transport winds.....West 6 to 7 knots shifting to the south
                    overnight.

TIME (MST)      6 PM      9 PM      MIDNGT    3 AM
Sky (%).........13        12        31        52
Weather cov.....
Weather type....NONE      NONE      NONE      NONE
Tstm cov........
CWR.............0         0         0         0
Temp............34        33        33        33
RH..............98        88        80        83
20 FT wind......W 4G7     SW 4G6    SW 5G7    S 5G8
Mix hgt (ft)....BLW100    BLW100    BLW100    BLW100
Transport wind..W 6       W 7       SW 6      S 6

.FRIDAY...

Sky/weather.........Mostly cloudy. Slight chance of rain showers
                    late in the afternoon.
Chance of pcpn......10 percent increasing to 20 percent late in the
                    afternoon.
Max temperature.....45-48 degrees.
Min humidity........50-53 percent.
20-foot winds.......Southeast winds 6 to 12 mph with gusts up to 18 mph
                    then shifting south after 1400 hours at 5 to 9 mph.
Mixing height.......1400 ft AGL increasing to 2900 ft AGL late in
                    the afternoon, then decreasing to 100 ft AGL
                    late in the afternoon.
Transport winds.....South 7 to 13 knots.

TIME (MST)      6 AM      9 AM      NOON      3 PM
Sky (%).........66        68        75        69
Weather cov.....
Weather type....NONE      NONE      NONE      NONE
Tstm cov........
CWR.............0         0         10        10
Temp............33        38        44        45
RH..............80        70        57        53
20 FT wind......SE 6G10   SE 8G14   SE 8G13   S 6G10
Mix hgt (ft)....BLW100    200       1400      1900
Transport wind..S 7       SE 9      S 12      S 11

.FORECAST DAYS 3 THROUGH 5...
.SATURDAY...
Mostly cloudy. Chance of showers and snow showers. Lows in the
upper 30s. Highs in the upper 40s. Southeast winds around 6 mph.
.SUNDAY...
Mostly cloudy. Chance of showers and snow showers. Lows in the
upper 30s. Highs in the mid 40s. Southwest winds around 5 mph.
.MONDAY...
Mostly clear. Lows in the mid 30s. Highs around 50. Light winds.

$$
Forecaster...STRONGMAN
Requested by...Chad Rice
Type of request...PRESCRIBED
.TAG 2526431.0/TWC
.DELDT 11/19/25
.FormatterVersion 2.0.0
.EMAIL chad.rice@usda.gov

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