351  
FNUS75 KFGZ 131218  
FWSFGZ  
 
SPOT FORECAST FOR FIREBOX CREEK...FTA  
NATIONAL WEATHER SERVICE FLAGSTAFF AZ  
518 AM MST SUN SEP 13 2026  
 
FORECAST IS BASED ON FORECAST START TIME OF 0600 MST ON SEPTEMBER 13.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE  
NATIONAL WEATHER SERVICE IN FLAGSTAFF, AZ  
   
DISCUSSION
 
A DISTURBANCE WILL MOVE INTO THE STATE TODAY WHICH  
WILL ACT AS A FOCUS MECHANISM FOR SHOWER AND THUNDERSTORM  
DEVELOPMENT OVER THE NEXT COUPLE DAYS. FOR TODAY THERE IS A 30%  
CHANCE OF THUNDERSTORMS DEVELOPING IN THE AFTERNOON HOURS. BRIEF  
HEAVY RAIN, GUSTY WINDS AND LIGHTNING WILL BE THE HAZARDS WITH  
THESE STORMS. STORM DEVELOPMENT IS EXPECT TO CEASE TONIGHT AND IT  
WILL BE DRY. ON MONDAY THE SHOWERS AND THUNDERSTORMS WILL BE MORE  
NUMEROUS OVER THE AREA AS THE DISTURBANCE PUSHES INTO THE EASTERN  
PART OF THE STATE. HEAVY RAIN, FREQUENT LIGHTNING, GUSTY WINDS  
AND AREAS OF FLASH FLOODING WILL BE POSSIBLE WITH THESE STORMS.  
STORMS MAY LAST THROUGHOUT THE NIGHT MONDAY AND INTO THE EARLY  
MORNING HOURS ON TUESDAY.  
 
   
TODAY
 
 
SKY/WEATHER.........MOSTLY SUNNY. CHANCE OF SHOWERS AND  
THUNDERSTORMS IN THE AFTERNOON.  
CHANCE OF PCPN......30 PERCENT.  
CHANCE LIGHTNING....10 PERCENT INCREASING TO 30 PERCENT IN THE  
AFTERNOON.  
MAX TEMPERATURE.....70-74.  
MIN HUMIDITY........46-50 PERCENT.  
WIND (20 FT)........SW 5-10 MPH. GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS IN THE  
AFTERNOON.  
MAX VENT RATE.......EXCELLENT.  
CLEARING INDEX......1208.  
MIXING HEIGHT.......9300 FT AGL.  
TRANSPORT WINDS.....SOUTH 5 TO 10 KNOTS SHIFTING TO THE SOUTHWEST  
LATE IN THE AFTERNOON.  
   
TONIGHT
 
 
SKY/WEATHER.........MOSTLY CLOUDY. CHANCE OF SHOWERS AND  
THUNDERSTORMS IN THE EVENING, THEN SLIGHT  
CHANCE OF SHOWERS AND THUNDERSTORMS OVERNIGHT.  
CHANCE OF PCPN......30 PERCENT.  
CHANCE LIGHTNING....30 PERCENT DECREASING TO 10 PERCENT OVERNIGHT.  
MIN TEMPERATURE.....51-55.  
MAX HUMIDITY........94-98 PERCENT.  
WIND (20 FT)........S 0-5 MPH. GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS.  
MIN VENT RATE.......POOR.  
CLEARING INDEX......2.  
MIXING HEIGHT.......100 FT AGL.  
TRANSPORT WINDS.....SOUTHEAST AROUND 5 KNOTS.  
   
MONDAY
 
 
SKY/WEATHER.........PARTLY SUNNY. SLIGHT CHANCE OF SHOWERS AND  
THUNDERSTORMS IN THE MORNING, THEN SHOWERS AND  
THUNDERSTORMS LIKELY IN THE AFTERNOON.  
CHANCE OF PCPN......60 PERCENT.  
CHANCE LIGHTNING....20 PERCENT INCREASING TO 60 PERCENT IN THE  
AFTERNOON.  
MAX TEMPERATURE.....66-70.  
MIN HUMIDITY........53-57 PERCENT.  
WIND (20 FT)........SW 5-10 MPH. GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS.  
MAX VENT RATE.......GOOD.  
CLEARING INDEX......599.  
MIXING HEIGHT.......4600 FT AGL.  
TRANSPORT WINDS.....SOUTH 5 TO 10 KNOTS SHIFTING TO THE SOUTHWEST  
AROUND 15 KNOTS IN THE AFTERNOON.  
 
A WEATHER FORECAST TABLE FOR YOUR SPOT LOCATION IS LINKED.  
THE INFORMATION PROVIDED BY THIS SITE IS FOR PLANNING PURPOSES ONLY  
AND IS NOT INTENDED TO SUBSTITUTE INFORMATION PROVIDED BY AN OFFICIAL  
NATIONAL WEATHER SERVICE SPOT FORECAST.  
HTTPS://WEATHER.GOV/DLH/FWD?LAT=33.8894&LON=-109.7617&CLAT=33.8894&CLON=-109.7617  
 

 
FORECASTER...BERNHART  
REQUESTED BY...AZ-SDC  
TYPE OF REQUEST...WILDFIRE  
.TAG 2621660.2/FGZ  
.DELDT 09/13/26  
.FORMATTERVERSION 2.0.0  
.EMAIL AZSDC@FIRENET.GOV,DANNY.TAYLOR@BIA.GOV,J.NOSIE23@GMAIL.COM  
 
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