810  
FXUS65 KBOU 300539  
AFDBOU  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
1139 PM MDT TUE SEP 29 2026  
   
KEY MESSAGES  
 
- RAIN CHANCES INCREASE OVERNIGHT INTO WEDNESDAY AFTERNOON, WITH  
THE HIGHEST RAIN CHANCES TO THE SOUTH OF THE URBAN CORRIDOR.  
RAIN WILL GENERALLY BE LIGHT, BUT A FEW LOCALIZED AREAS COULD  
SEE BRIEF PERIODS OF HEAVIER RAINFALL. HIGHEST RAIN AMOUNTS ARE  
FORECAST TO REMAIN SOUTH OF OUR FORECAST AREA.  
 
- FLOOD WATCH IN EFFECT FOR SOUTHERN LINCOLN AND FAR SOUTHEASTERN  
ELBERT COUNTIES THROUGH THURSDAY MORNING.  
 
- RAIN CHANCES DECREASE LATE THURSDAY, LEADING TO WARMER AND DRIER  
CONDITIONS FOR THE WEEKEND AND EARLY NEXT WEEK.  
 
 
   
DISCUSSION /THROUGH TUESDAY/  
 
ISSUED AT 1139 PM MDT TUE SEP 29 2026  
 
LOOKING AT SATELLITE LATE THIS EVENING, THE UPPER LEVEL LOW IS  
CURRENTLY MOVING OUT OF SOUTHERN CALIFORNIA AND INTO ARIZONA WITH  
WIDELY SCATTERED SHOWERS AND STORMS AHEAD OF THE TROUGH TO OUR  
SOUTH. THE SHOWERS AND STORMS WILL GRADUALLY MOVE NORTH/NORTHEAST  
AS THE SURFACE LOW TRACKS NORTHEAST. LIGHT SHOWERS ARE STARTING  
TO APPROACH SOUTHERN LINCOLN COUNTY AS OF LATE THIS EVENING. RAIN  
CHANCES WILL INCREASE FOR THE PALMER DIVIDE AREA LATE OVERNIGHT  
THROUGH EARLY WEDNESDAY MORNING AND THE URBAN CORRIDOR BY THE  
LATE MORNING TO EARLY AFTERNOON. MODELS HAVE CONTINUED TO TREND  
LOWER FOR RAIN AMOUNTS IN OUR AREA, DUE TO A MORE SOUTHERN TRACK  
OF THE UPPER LOW AND EASTWARD TRACK OF THE SURFACE LOW. WITH THE  
SURFACE LOW BEING A BIT MORE EAST, IT'S MUCH HARDER TO GET THE  
HIGHER MOISTURE TO WRAP AROUND INTO OUR AREA. WE WILL HAVE ENOUGH  
MOISTURE FOR SOME LIGHTER RAIN ACTIVITY AND WE ARE STILL EXPECTING  
RAIN ON WEDNESDAY FOR MANY AREAS SOUTH OF I-76, BUT FORECAST  
AMOUNTS HAVE DECREASED AND THE RISK FOR FLOODING HAS DECREASED.  
 
THE BEST CHANCE FOR HIGHER RAIN AMOUNTS IN OUR AREA WILL BE IN OUR  
SOUTHERN MOST COUNTIES (LINCOLN AND POTENTIALLY THE PALMER DIVIDE),  
BUT THE HIGHEST RAIN AMOUNTS FOR THIS SYSTEM ARE EXPECTED TO  
REMAIN TO THE SOUTHEAST OF OUR FORECAST AREA. WE'VE LEFT THE  
FLOOD WATCH FOR THE SOUTHEASTERN ELBERT AND SOUTHERN LINCOLN  
COUNTY ZONE, BUT THERE'S STILL UNCERTAINTY ON IF THE HEAVIER  
RAINFALL WILL EVEN MAKE IT THAT FAR NORTH. SHORT OF SOME UNLIKELY  
MESOSCALE FEATURE SETTING UP, LIKE AN MCV, WE'RE LOOKING AT MUCH  
LOWER RAIN TOTALS FOR OUR AREA THAN PREVIOUSLY FORECAST. OVERALL  
FOR OUR FORECAST AREA, EXPECT MORE OF A STEADY LIGHT RAIN EVENT  
FOR AREAS SOUTH OF I-76 TOMORROW, WITH A SLIGHT CHANCE FOR ONE OR  
TWO AREAS TO SEE HIGHER AMOUNTS APPROACHING ONE TO TWO INCHES.  
 
THIS SYSTEM IS FORECAST TO MOVE OFF TO THE EAST LATE THURSDAY, WITH  
UPPER LEVEL RIDGING BUILDING IN BEHIND IT. THE RIDGING SHOULD  
HOLD THROUGH THE WEEKEND, BRINGING WARMER AND DRIER CONDITIONS.  
HIGHS ARE FORECAST TO BE ABOVE NORMAL FRIDAY THROUGH MONDAY, WITH  
HIGHS APPROACHING THE LOW TO MID 80S FOR PORTIONS OF THE PLAINS BY  
MONDAY. OUR NEXT CHANCE FOR RAIN COULD ACCOMPANY AN UPPER LEVEL  
SHORTWAVE LATE MONDAY INTO TUESDAY, BUT RAIN CHANCES REMAIN LOW  
(<30%) FOR NOW.  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/  
 
ISSUED AT 1139 PM MDT TUE SEP 29 2026  
 
THERE IS STILL A GOOD AMOUNT OF UNCERTAINTY REGARDING CEILING  
HEIGHTS AND RAINFALL PLACEMENT FOR THE UPCOMING SYSTEM ON  
WEDNESDAY. IT APPEARS DEN AND BJC WILL BE ON THE EDGE OF THE LOWER  
CLOUDS (2,500–5,000 FT) AND RAIN. BEST CHANCE FOR THE LOWER CLOUDS  
AT DEN AND BJC WILL BE 14-22Z. AFTER 00Z, DRIER AIR MOVES IN, BUT  
MODEL CROSS SECTIONS STILL HOLD ONTO A SCT-BKN LAYER AROUND  
6000-8000 FEET. AT APA, RAIN AND LOWER CLOUDS ARE EXPECTED TO MOVE  
IN BETWEEN 13Z AND 14Z AND LINGER THROUGH MOST OF THE AFTERNOON.  
IMPROVING CONDITIONS ARE EXPECTED BY 00Z THURSDAY AS WELL. AS FAR  
AS WINDS GO, LIGHT SOUTHERLY WINDS WILL TRANSITION TO THE NORTH BY  
12Z AND REMAIN NORTH TO NORTHEAST THROUGH WEDNESDAY.
 
 
 
   
BOU WATCHES/WARNINGS/ADVISORIES  
 
FLOOD WATCH THROUGH THURSDAY MORNING FOR COZ047.  
 
 
 
 
 
DISCUSSION...AP  
AVIATION...MEIER  
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