094  
FXUS65 KBOU 301117  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
517 AM MDT WED JUL 30 2025  
   
KEY MESSAGES
 
 
 
- COOLER AND MORE ACTIVE WEATHER PATTERN WITH SCATTERED  
THUNDERSTORMS AND LOCALLY HEAVY RAIN THROUGH FRIDAY,  
PARTICULARLY EAST OF THE CONTINENTAL DIVIDE.  
 
- DRIER AND WARMER WEATHER PATTERN BEGINS THIS WEEKEND AND LASTS  
THROUGH EARLY NEXT WEEK.  
 

 
   
UPDATE
 
 
ISSUED AT 323 AM MDT WED JUL 30 2025  
 
CONFIDENCE WHERE HEAVIER RAINFALL WILL OCCUR THIS AFTN AND EVENING  
IS ON THE LOW SIDE. PW VALUES WILL REMAIN ABOVE NORMAL FROM THE  
I-25 CORRIDOR EASTWARD ACROSS THE PLAINS. OVERALL INSTABILITY  
WILL SEE MLCAPE UP TO 1500 J/KG WITH SLIGHTLY STRONGER FLOW IN THE  
MID LEVELS AS COMPARED TO YESTERDAY. THIS SUGGESTS STORMS WILL  
MOVE TODAY AND NOT REMAIN STATIONARY AS OCCURRED YESTERDAY.  
HOWEVER, STORMS COULD STILL PRODUCE FROM 1" TO 1.5" OF RAIN IN A  
FEW AREAS IN A SHORT PERIOD OF TIME. HEAVIEST RAIN ON TUESDAY WAS  
OVER PORTIONS OF ELBERT AND LINCOLN COUNTIES SO ADDITIONAL HEAVY  
RAIN MAY LEAD TO SOME FLASH FLOODING. THUS WILL ISSUE A FLOOD  
WATCH FOR THESE AREAS FOR THIS AFTN INTO THE EARLY EVENING HOURS.  
 
FINALLY WITH SLIGHTLY BETTER SHEAR TODAY CAN'T RULE OUT A FEW  
MARGINAL SVR STORMS AS WELL ACROSS THE I-25 CORRIDOR AND PLAINS.  
 

 
   
DISCUSSION /THROUGH TUESDAY/
 
 
ISSUED AT 213 PM MDT TUE JUL 29 2025  
 
SATELLITE SHOWS CLEARING OF THE STRATUS DECK IN MOST AREAS, BUT A  
PRETTY HEALTHY MID/HIGH LEVEL CLOUD DECK HOLDING STRONG. THE  
GREATEST SURFACE HEATING WAS OVER THE NORTHEAST AND EAST CENTRAL  
PLAINS, WHERE CIN WAS DECREASING AND MLCAPE RANGED ANYWHERE FROM  
1000-3000 J/KG. THE HIGHEST MLCAPE VALUES WERE ALONG/NORTH OF  
I-76, BUT THAT'S ALSO WHERE THE CAP IS STRONGEST. ACARS STILL  
SHOWS A PRETTY HEALTHY CAP AS OF 20Z, BUT IT IS WEAKENING. WE  
STILL THINK THE HIGHEST RISK OF STRONG/SEVERE STORMS WOULD BE OVER  
LINCOLN COUNTY WHERE THE WEAKEST CAP EXISTS. THE PALMER DIVIDE  
AND POINTS EAST ACROSS THE PLAINS WOULD BE MOST FAVORED FOR HEAVY  
RAINFALL - SEE HYDRO DISCUSSION BELOW. OVERALL, WE'LL KEEP  
SCATTERED THUNDERSTORMS IN THE FORECAST THROUGH THIS EVENING, WITH  
A GRADUAL DECREASE FROM WEST TO EAST ACROSS THE FORECAST AREA.  
JUST A SLIGHT CHANCE THAT A FEW SHOWERS/STORMS LINGER PAST  
MIDNIGHT OVER THE NORTHEAST PLAINS. THAT WOULD BE FURTHER  
SUPPORTED BY PASSAGE OF ANOTHER PUSH/WEAK COLD FRONT LATE TONIGHT.  
 
ON WEDNESDAY, THE MAIN CONCERN WILL AGAIN BE STRONG THUNDERSTORMS  
WITH LOCALLY HEAVY RAIN AND A FLASH FLOOD THREAT. WE WILL HAVE A  
FRONTAL PUSH IN THE PRE-DAWN HOURS, AND POTENTIALLY ANOTHER  
REINFORCING SURGE DURING THE MORNING. THUS, THE HIGHEST INSTABILITY  
COULD VERY WELL BE PUSHED UP AGAINST THE FRONT RANGE FOOTHILLS,  
WHILE AT THE SAME TIME A STRONGER CAP DEVELOPS OVER THE EASTERN  
PLAINS. AT THIS TIME, THE GREATEST RISK FOR HEAVY RAINFALL AND  
FLASH FLOODING APPEARS TO BE SETTING UP FOR THE FOOTHILLS, PALMER  
DIVIDE, AND PORTIONS OF THE I-25 CORRIDOR WHERE THE GREATEST  
INSTABILITY/WEAKEST CAP IS FORECAST. AGAIN, MORE FLASH FLOOD  
THREAT DETAILS IN THE HYDRO DISCUSSION BELOW. TEMPERATURES WILL  
BE COOLER THAN TODAY WITH FURTHER COOL ADVECTION AND EXPECTED  
AREAS OF STRATUS IN THE MORNING.  
 
FOR THURSDAY, WE COULD BE LOOKING AT A REPEAT SCENARIO WITH  
SCATTERED THUNDERSTORMS AND LOCALLY HEAVY RAINFALL, AS VERY LITTLE  
CHANGES SYNOPTICALLY. THE UPPER LEVEL RIDGE HOLDS OVERHEAD, WITH  
WEAK SHEAR BUT A MOISTURE LADEN AIRMASS. FOR FRIDAY, THE RIDGE  
STARTS TO BREAK DOWN WITH A LITTLE MORE WESTERLY FLOW ALOFT. WHILE  
MOISTURE VALUES DECREASE SLIGHTLY, WE'LL LIKELY BE UNSTABLE ENOUGH  
TO SUPPORT SCATTERED AFTERNOON AND EARLY EVENING STORMS ONCE  
AGAIN.  
 
WE'LL SEE A STRONGER AND MORE ZONAL FLOW ALOFT DEVELOP THIS  
WEEKEND AS SHORTWAVE MOVES FROM THE GREAT BASIN THROUGH THE  
CENTRAL ROCKIES. THIS LIKELY MEANS DRIER WEATHER AND WARMER  
TEMPERATURES. WHILE AN EMBEDDED SHORTWAVE COULD BRING A DAY OF  
THUNDERSTORMS SATURDAY, THE ADDITIONAL DRYING/WARMING MEANS  
THEY'LL BE HIGHER BASED AND MORE CONDUCIVE TO GUSTY WINDS THAN  
MEANINGFUL RAINFALL. HIGHS ON THE PLAINS SHOULD REBOUND BACK TO  
90F OR HIGHER. PROGNOSTICATIONS FOR EARLY NEXT WEEK SHOW FLAT  
RIDGING ACCORDING TO THE ENSEMBLES, SO WE'LL HAVE A DRIER  
FORECAST WITH TEMPERATURES AT/ABOVE NORMAL.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
 
 
ISSUED AT 512 AM MDT WED JUL 30 2025  
 
STRATUS HAS FAILED TO DEVELOP EARLY THIS MORNING AND HAVE RATHER  
LOW CONFIDENCE IT WILL. THUS WILL ONLY MENTION A TEMPO GROUP  
THRU 15Z. WINDS WERE LIGHT NORTH AND MAY BECOME LIGHT AND VARIABLE  
BY 15Z. BETWEEN 17Z AND 18Z WILL SEE WINDS BECOME MORE ENE AND  
THEN EASTERLY BY 20Z. SHOULD SEE A ROUND OF TSTMS BETWEEN 21Z  
AND 00Z WITH BRIEF RESTRICTIONS TO CEILINGS AND VISIBILITY IF  
AIRPORTS TAKE A DIRECT HIT FROM STRONGER STORMS. BY 01Z TSTM  
ACTIVITY WILL MOVE OUT OF THE AREA. OVERNIGHT MAY SEE STRATUS  
DEVELOP BY 12Z THU.  
 

 
   
HYDROLOGY
 
 
ISSUED AT 323 AM MDT WED JUL 30 2025  
 
CONFIDENCE AS TO WHERE HEAVIER RAINFALL MAY OCCUR THIS AFTERNOON  
AND EVENING IS ON THE LOW SIDE. FOR NOW HAVE ISSUED A FLOOD WATCH  
ACROSS AREAS THAT RECEIVED HEAVER RAINFALL YESTERDAY WHICH WAS  
OVER PORTIONS OF ELBERT AND LINCOLN COUNTIES. ALSO MAY SEE AN  
ENHANCED THREAT OF FLASH FLOODING OVER ALEXANDER MOUNTAIN AND  
SOUTHEAST PORTIONS OF CAMERON PEAK IF A STRONGER STORM MOVES  
ACROSS.  
 

 
   
BOU WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH FROM 1 PM MDT THIS AFTERNOON THROUGH THIS EVENING  
FOR COZ041-046-047.  
 

 
 

 
 
UPDATE...RPK  
DISCUSSION...BARJENBRUCH  
AVIATION...RPK  
HYDROLOGY...RPK  
 
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