235  
FXUS65 KBOU 302017  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
217 PM MDT MON JUN 30 2025  
   
KEY MESSAGES
 
 
 
- SUMMER HEAT RETURNS TUESDAY AND WEDNESDAY, STILL A FEW STORMS  
MAINLY OVER THE MOUNTAINS.  
 
- STORM CHANCES INCREASE THURSDAY.  
 
- SCATTERED THUNDERSTORMS AND NORMAL TEMPERATURES ARE EXPECTED FOR  
THE FOURTH OF JULY AND INDEPENDENCE DAY WEEKEND.  
 

 
   
DISCUSSION /THROUGH MONDAY/
 
 
ISSUED AT 217 PM MDT MON JUN 30 2025  
 
A FEW SHOWERS AND THUNDERSTORMS HAD DEVELOPED IN THE MORE  
UNSTABLE AIRMASS OVER THE MOUNTAINS THIS AFTERNOON, BUT SO FAR  
COVERAGE HAS BEEN A LITTLE LESS THAN ANTICIPATED. WE STILL THINK  
SOUTH PARK WILL END UP WITH THE HIGHEST COVERAGE LATE THIS  
AFTERNOON INTO EARLY EVENING. SOME LATE DAY INSTABILITY/WEAKENING  
CIN MAY ALLOW A FEW SHOWERS/ISOLATED STORMS TO MOVE ONTO THE  
ADJACENT PLAINS SOUTH OF I-70 (10-30% CHANCE) EARLY THIS EVENING.  
 
FOR TUESDAY AND WEDNESDAY, THE CENTER OF THE UPPER LEVEL RIDGE  
WILL SHIFT SLOWLY EAST ACROSS COLORADO, BRINGING A RETURN OF  
SUMMER WARMTH AND A GENERAL DECREASE IN SHOWER/STORM COVERAGE.  
HOWEVER, THERE WILL BE SOME MOISTURE STUCK UNDER THE RIDGE  
TUESDAY, AND ENOUGH WESTERLY FLOW ALOFT YET TO ALLOW A FEW HIGH  
BASED SHOWERS/STORMS TO PUSH EAST FROM THE MOUNTAINS ONTO THE  
PLAINS. MLCAPE IS LIMITED (OUTSIDE OF THE NORTHEAST CORNER) SO  
GENERALLY GUSTY WINDS AND LIGHTNING WOULD BE THE MAIN THREATS. THE  
FAR NORTHEAST CORNER WOULD HAVE A LOW THREAT OF SEVERE WITH  
MLCAPE 1000 J/KG OR GREATER THERE. ON WEDNESDAY, THE UPPER LEVEL  
RIDGE IS EXPECTED TO SHIFT SLIGHTLY EASTWARD INTO EASTERN  
COLORADO. THUS, WITH LITTLE/NO WESTERLY FLOW ALOFT IT WILL BE VERY  
HARD TO GET A STORM ON THE PLAINS. MOUNTAIN AREAS SHOULD STILL  
SEE ISOLATED TO SCATTERED LATE DAY CONVECTION.  
 
FOR THURSDAY, WE'LL STILL ON TRACK TO SEE A PLUME OF SUB TROPICAL  
MOISTURE MOVE NORTHWARD. THIS OCCURS IN DEEPER SOUTHERLY FLOW  
DEVELOPING BETWEEN THE UPPER LEVEL HIGH SHIFTING INTO THE CENTRAL  
AND SOUTHERN PLAINS AND A WEAK TROUGH LIFTING NORTHWARD ACROSS  
THE DESERT SOUTHWEST. AS A RESULT, THURSDAY'S CONVECTIVE INTENSITY  
AND COVERAGE IS EXPECTED TO INCREASE, WITH LIKELY THE BEST CHANCE  
(40-60%) OF RAIN THIS WEEK.  
 
AS DISCUSSED YESTERDAY, THERE IS ALSO A THREAT THAT THE  
APPROACHING TROUGH FROM THE SOUTHWEST COULD END UP BEING A PLAYER  
ON INDEPENDENCE DAY WEATHER. HOWEVER, THE LATEST TRENDS OVER THE  
LAST 24 HOURS ARE FOR A FASTER AND STRONGER EJECTING TROUGH  
THURSDAY AND THURSDAY NIGHT. IF THIS OCCURS THEN THAT SHORTWAVE  
COULD LITERALLY STEAL MUCH OF THE THUNDER FROM FRIDAY'S  
(INDEPENDENCE DAY) FORECAST. IT'S STILL TOO EARLY TO TELL, BUT THE  
LATEST TRENDS WOULD SUGGEST A DECREASE IN STORM COVERAGE AND OUR  
POPS HAVE BEEN ADJUSTED ACCORDINGLY WITH THIS LATEST GUIDANCE.  
 
TYPICAL SUMMER WEATHER IS THEN EXPECTED THROUGH NEXT WEEKEND, WITH  
TEMPERATURES AT/JUST ABOVE NORMAL LEVELS AND A FEW RUMBLES OF  
THUNDER EACH AFTERNOON AND EVENING.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
 
 
ISSUED AT 1146 AM MDT MON JUN 30 2025  
 
STRATUS DECK IS BREAKING UP ON SATELLITE AS DAYTIME HEATING OCCURS,  
SO FURTHER IMPROVEMENT IS EXPECTED THROUGH 21Z WITH VFR  
CONDITIONS DEVELOPING. ANY THUNDERSTORMS THIS AFTERNOON AND  
EVENING SHOULD STAY CLOSER, IF NOT TOTALLY CONFINED, TO THE  
HIGHER TERRAIN SOUTHWEST OF DENVER AS THE LOW LEVELS ARE QUITE  
STABLE. WINDS ARE STARTING LIGHT AND VARIABLE, BUT SHOULD PICK UP  
A MORE EASTERLY DIURNAL COMPONENT 20Z-24Z. THEN LOOK FOR A SLOW  
RETURN TO NORMAL SOUTH/SOUTHWEST WINDS OVERNIGHT INTO TUESDAY  
MORNING. HIGH BASED SHOWERS AND STORMS ARE POSSIBLE TUESDAY AFTER  
22Z (30% CHANCE) SO HAVE INCLUDED THAT FOR NOW. GUSTY/VARIABLE  
WINDS TO 35+ KTS WILL BE THE MAIN THREAT TO AVIATION.  
 

 
   
BOU WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
DISCUSSION...BARJENBRUCH  
AVIATION...BARJENBRUCH  
 
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