454  
FXUS65 KPUB 172038  
AFDPUB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PUEBLO CO  
238 PM MDT THU SEP 17 2026  
   
KEY MESSAGES
 
 
- ONE MORE DAY OF WIDESPREAD SHOWERS AND THUNDERSTORMS OVER THE  
MOUNTAINS ON FRIDAY, WITH POCKETS OF HEAVY RAINFALL AGAIN  
POSSIBLE.  
 
- THUNDERSTORM ACTIVITY MAY THEN INCREASE OVER THE PLAINS LATE  
SATURDAY INTO SUNDAY AS A COLD FRONT MOVES THROUGH THE AREA.  
 
- A BIT DRIER LATE SATURDAY INTO SUNDAY OVER THE MOUNTAINS,  
BEFORE COOLER AND POSSIBLY WETTER CONDITIONS RETURN NEXT WEEK.  
 

 
   
SHORT TERM /THROUGH FRIDAY/
 
 
ISSUED AT 135 PM MDT THU SEP 17 2026  
 
CURRENTLY, INITIAL S/W TROUGH WHICH BROUGHT WIDESPREAD SHOWERS  
TO MANY LOCATIONS OVERNIGHT/EARLY THIS MORNING WAS LIFTING INTO  
NRN CO, WITH A PRONOUNCED DOWNTURN IN PRECIP ACROSS THE AREA  
EARLY THIS AFTERNOON. STILL SOME LIGHT TO BRIEFLY MODERATE RAIN  
IN SPOTS ALONG THE CONTINENTAL DIVIDE AS OF 130 PM, BUT OVERALL,  
NEXT ROUND OF THUNDERSTORM DEVELOPMENT HAS BEEN SLOWED BY  
CLOUDS AND WEAK SUBSIDENCE BEHIND THE DEPARTING WAVE. MOST  
MODELS SUGGEST STORM REDEVELOPMENT AFTER 3 PM, WITH ERN SAN  
JUANS/SRN SAN LUIS VALLEY AND THE SRN SANGRES LOOKING MOST  
FAVORED FOR STRONGER ACTIVITY AS CONVECTION MOVES NORTHWARD OUT  
OF NM. PEAK STORM COVERAGE ACCORDING TO MANY CAMS MAY NOT COME  
UNTIL 6-7 PM, WITH EVEN SOME WEAKENING ACTIVITY DRIFTING INTO  
THE I-25 CORRIDOR POSSIBLE. WILL KEEP FLASH FLOOD WATCH UP UNTIL  
MIDNIGHT FOR THE SW MOUNTAINS, WHERE MODELS SUGGEST HEAVIER  
RAIN IS POSSIBLE THROUGH AT LEAST SUNSET. OVERNIGHT, CONVECTION  
DIMINISHES GREATLY AFTER MIDNIGHT, WITH ONLY SOME LINGERING  
SHOWERS ALONG THE CONTINENTAL DIVIDE INTO FRI MORNING. ON FRI,  
ONE MORE DAY OF WIDESPREAD MOUNTAIN SHOWERS/THUNDERSTORMS  
EXPECTED, AS PACIFIC NW UPPER LOW BEGINS IT'S EASTWARD TREK INTO  
THE ROCKIES. BEST STORM COVERAGE AGAIN ALONG THE CONTINENTAL  
DIVIDE, WITH MAINLY ISOLATED STORMS FROM I-25 EASTWARD. MAX  
TEMPS WILL NUDGE UPWARD, WITH SOME LOW/MID 90S OVER THE  
SOUTHEAST PLAINS.  
 

 
   
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/
 
 
ISSUED AT 135 PM MDT THU SEP 17 2026  
 
ON SATURDAY, UPPER LOW MOVES INTO WRN WY, WITH STRENGTHENING WLY  
FLOW OVER CO BRINGING IN A DRIER AIR MASS, ESPECIALLY OVER THE  
MOUNTAINS. WHILE WE WON'T SHUT OFF CONVECTION COMPLETELY AS  
UPPER TROUGH EXTENDING SOUTH FROM THE WY LOW WILL PROVIDE SOME  
MODEST UPWARD MOTION, STORM COVERAGE/STRENGTH WILL BE LOWER  
THAN THE PAST FEW DAYS OVER MOST OF THE HIGHER TERRAIN SAT  
AFTERNOON AND EVENING. FOR THE EASTERN MOUNTAINS AND SOUTHEAST  
PLAINS, FORECAST HINGES ON HOW FAST COLD FRONT ARRIVES AND HOW  
MUCH LOW LEVEL INSTABILITY DEVELOPS BEHIND IT BY LATE DAY. MOST  
MODEL FORECASTS HAVE BOUNDARY NEAR THE ARKANSAS RIVER BY LATE  
SAT AFTERNOON, THEN PROGRESSING SOUTH TOWARD THE NM BORDER  
THROUGH THE EVENING. COMBINATION OF BEST UPPER FORCING AND  
GREATEST LOW LEVEL INSTABILITY ARE CURRENTLY FORECAST OVER NERN  
CO SAT AFTERNOON/EVENING, THOUGH INSTABILITY/SHEAR OVER SERN CO  
LOOK MORE THAN SUFFICIENT FOR STORMS TO BUILD S-SW INTO THE  
AREA, ESPECIALLY MID TO LATE EVENING. NUDGED UP NBM POPS A BIT  
SAT AFTERNOON/EVENING TO ACCOUNT FOR THIS SCENARIO, THOUGH  
OVERALL BLENDED GUIDANCE DIDN'T LOOK TOO BAD FOR THIS PERIOD.  
 
STRONG WLY FLOW ALOFT ON SUN WILL DRY OUT THE MOUNTAINS, WITH  
CONVECTION LIMITED TO THE ERN SLOPES OF THE SANGRES/WETS/PIKES  
PEAK. FOR THE I-25 CORRIDOR AND THE SERN PLAINS, POST FRONTAL  
UPSLOPE WILL PERSIST, KEEPING DEWPOINTS IN THE 50S EAST OF I-25  
THROUGH THE DAY. 0-6KM SHEAR OF 35-45 KTS WILL BE IN PLACE,  
WITH MODELS SHOWING CAPE IN THE 1K-2K J/KG RANGE FROM AFTERNOON  
INTO THE EVENING, WHILE 70-80 KT JET STREAK AT 250 MOVES  
OVERHEAD LATE IN THE DAY. SET-UP LOOKS FAVORABLE FOR  
STRONG/SEVERE STORMS EAST OF THE MOUNTAINS, THOUGH OUTFLOW AND  
POTENTIAL CLOUD COVER FROM SAT NIGHT/EARLY SUN MORNING STORMS  
COULD LIMIT INSTABILITY, ESPECIALLY INTO EARLY/MID AFTERNOON.  
CURRENT FORECAST HAS MAINLY ISOLATED POPS OVER THE PLAINS SUN  
AFTERNOON, THEN WIDESPREAD STORMS ALONG/EAST OF I-25 SUN EVENING  
AS ACTIVITY INITIALLY ALONG THE PALMER INTENSIFIES AND EXPANDS  
SOUTH AND EAST. MAX TEMPS BEHIND THE FRONT ON SUN WILL RUN 5-10  
DEGF COOLER THAN SAT, WHILE MOUNTAINS SEE LITTLE CHANGE.  
 
LOW CONFIDENCE FORECAST FOR MON-WED AS MODEL SOLUTIONS HAVE  
BOUNCED AROUND A GOOD DEAL, THOUGH ROUGH CONSENSUS APPEARS TO  
FAVOR A RETURN OF LOW/MID LEVEL MOISTURE TO MUCH OF THE AREA AS  
WE APPROACH MID-WEEK, WITH WESTERN U.S. UPPER TROUGH/SERN U.S.  
UPPER RIDGE PATTERN POTENTIALLY REFORMING. BLENDED MODEL  
GUIDANCE SHOWS COOLER THAN AVERAGE TEMPERATURES AND DAILY  
CHANCES FOR SHOWERS/THUNDERSTORMS, WHICH LOOKS FINE FOR NOW.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
 
 
ISSUED AT 1141 AM MDT THU SEP 17 2026  
 
KCOS AND KPUB: VFR CONDITIONS THE NEXT 24 HRS, WITH A PROB30 FOR  
A BRIEF -TSRA FROM LATE THIS AFTERNOON INTO EARLY THIS EVENING.  
S-SW WINDS WILL INCREASE AT BOTH TERMINALS THIS AFTERNOON, WITH  
GUSTS TO 20-25 KNOTS EXPECTED. WINDS THEN DECREASE OVERNIGHT  
INTO FRIDAY MORNING.  
 
KALS: VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS, WITH A  
PROB30 FOR -TSRA FROM LATE THIS AFTERNOON INTO THIS EVENING. THE  
MAIN STORM THREATS WILL BE GUSTY WINDS TO 35 KTS AND AND BRIEF  
HEAVY RAINFALL. VCSH WILL LINGER UNTIL AROUND 08Z, THEN MOST  
PRECIP SHIFTS EAST OF THE AREA. S-SW WINDS WILL REMAIN GUSTY  
(20-25 KTS) THIS AFTERNOON, BEFORE DIMINISHING THIS EVENING AND  
OVERNIGHT.  
 

 
   
PUB WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR COZ067-068.  
 

 
 

 
 
SHORT TERM...PETERSEN  
LONG TERM...PETERSEN  
AVIATION...PETERSEN  
 
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