823  
FXUS65 KGJT 292016  
AFDGJT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND JUNCTION CO  
216 PM MDT TUE SEP 29 2026  
   
KEY MESSAGES  
 
- SCATTERED TO WIDESPREAD PRECIPITATION SHOWERS AND STORMS  
CONTINUE.  
 
- FLOODING CONCERNS ARE INCREASED FOR RAIN-SOAKED TERRAIN,  
ESPECIALLY WITHIN AND ADJACENT TO THE SOUTHERN SAN JUANS.  
 
- A FLOOD WATCH IS IN EFFECT FOR SOUTHEAST UTAH AND SOUTHWEST  
COLORADO THROUGH 6AM WEDNESDAY. THE FLOOD WATCH HAS BEEN  
EXTENDED FOR THE SAN JUAN MOUNTAINS AND PART OF THE SAN JUAN  
RIVER BASIN THROUGH 6AM THURSDAY.  
 
 
   
DISCUSSION  
 
ISSUED AT 1231 PM MDT TUE SEP 29 2026  
 
ACTIVE WEATHER THROUGH LATE WEDNESDAY EVENING:  
 
THE ONGOING ACTIVE WEATHER WILL CONTINUE THROUGH LATE WEDNESDAY  
EVENING AS A LOW PRESSURE SYSTEM SLOWLY MOVES ACROSS THE  
SOUTHWEST AND EAST OF THE ROCKY MOUNTAINS BY THURSDAY MORNING.  
SATELLITE IMAGERY SHOWS THE LOW IS CURRENTLY CENTERED OVER  
NORTHWESTERN ARIZONA, WHICH IS SUPPORTING A TRANSITION FROM  
SOUTHWESTERLY TO SOUTHEASTERLY FLOW OVER OUR AREA BY THIS  
EVENING. UPPER LEVEL SUPPORT IS LIMITED TODAY WHILE THE BULK OF  
FORCING AND MOISTURE IS TO OUR SOUTH, SO ISOLATED TO SCATTERED  
SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGH THIS EVENING,  
PRIMARILY SOUTH OF I-70. LATE THIS EVENING MOISTURE AND FORCING  
WILL INCREASE AS THE LOW MOVES EASTWARD, WHICH WILL FURTHER RAISE  
PRECIPITATION CHANCES SOUTH OF I-70. PRECIPITATION CHANCES WILL  
GRADUALLY TRANSITION TO FAVOR COLORADO'S HIGHER TERRAIN THROUGH  
THE DAY WEDNESDAY. WEDNESDAY'S ACTIVITY MAY BE MORE CONVECTIVE,  
WHICH INCREASES THE POSSIBILITY FOR PERIODS OF HEAVY RAINFALL.  
AS SUCH, THE FLOOD WATCH HAS BEEN EXTENDED FOR THE SAN JUANS AND  
PARTS OF THE SAN JUAN RIVER BASIN THROUGH 6AM THURSDAY MORNING.  
THE FLOOD WATCH REMAINS IN EFFECT THROUGH 6AM WEDNESDAY MORNING  
FOR THE REMAINING AREAS OF SOUTHWEST COLORADO AND EASTERN UTAH.  
PERIODS OF PROLONGED OR HEAVY RAINFALL INCREASE CONCERNS FOR  
FLOODING AND FLASH FLOODING, RESPECTIVELY, ESPECIALLY IN AREAS  
THAT HAVE RECENTLY RECEIVED SUBSTANTIAL RAIN. RIVERS MAY RISE  
OUT OF THEIR BANKS EVEN AFTER RAINFALL HAS ENDED OVER AN AREA,  
SO BE SURE TO MONITOR THE FORECAST AND HAVE A WAY TO RECEIVE  
WEATHER ALERTS.  
 
DRY AND WARMER THURSDAY THROUGH THE WEEKEND:  
 
HIGH PRESSURE MOVES INTO OUR REGION ON THURSDAY AS THE LOW  
PRESSURE SYSTEM MOVES TO OUR EAST. THIS PATTERN SHIFT WILL  
BRING DRY AND WARMER WEATHER THROUGH AT LEAST THE WEEKEND. HIGH  
TEMPERATURES ARE FORECAST TO CLIMB FROM NEAR NORMAL ON THURSDAY  
TO 5 TO 10 DEGREES ABOVE NORMAL THIS WEEKEND.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/  
 
ISSUED AT 1140 AM MDT TUE SEP 29 2026  
 
ABUNDANT MOISTURE WILL LEAD TO CONTINUED CLOUD COVER AND  
SCATTERED SHOWERS OVER THE REGION THIS AFTERNOON. SHOWERS WILL  
BECOME WIDESPREAD THIS EVENING SOUTH OF I-70 WITH LESSER  
COVERAGE OVER NORTHERN SITES. TERRAIN OBSCURATION WILL ALSO BE  
WIDESPREAD LEADING TO AREAS OF ILS TO MVFR VISIBILITY IN  
ADJACENT VALLEYS AND ASSOCIATED TAF SITES. LOWER CLOUDS  
LINGERING BEHIND THE MOISTURE COULD ALSO LEAD TO MVFR/IFR  
CONDITIONS AS STRATUS AND/OR FOG DEVELOPS.  
 
 
   
HYDROLOGY  
 
ISSUED AT 208 PM MDT TUE SEP 29 2026  
 
TROPICAL MOISTURE CONTINUES TO FUEL A SHIELD OF PRECIPITATION  
DRIFTING NORTH ACROSS NEW MEXICO. WHILE AREAS NORTH OF THE FOUR  
CORNERS HAVE SEEN A DOWNWARD TICK IN SHOWER COVERAGE, HIRES  
GUIDANCE MAINTAINS ISOLATED TO SCATTERED SHOWERS REDEVELOPING  
ACROSS THE SOUTHWEST SAN JUANS THIS AFTERNOON. AS A RESULT,  
EXPECT PERIODS OF HEAVY RAINFALL DUE TO ADDITIONAL SHOWERS WITH  
EMBEDDED THUNDERSTORMS POSSIBLE. LOCALIZED HEAVY RAINFALL OVER  
ALREADY SATURATED SOILS WILL POSE A THREAT TO OUR STEEP AND  
FLASHY TERRAIN AS WELL AS RECENT BURN SCARS. STORM ACTIVITY IS  
PRIMARILY FAVORED ACROSS THE SOUTHERN TIER OF THE FORECAST AREA.  
 
THE CONVECTIVE POTENTIAL WANES AFTER SUNSET; HOWEVER, AS THE  
CLOSED LOW LIFTS TOWARDS THE FOUR CORNERS TONIGHT, ANOTHER ROUND  
OF SHOWERS AND THUNDERSTORMS REDEVELOPS. EMBEDDED THUNDERSTORMS  
AND ADDITIONAL RAIN EXPECTED THROUGH WEDNESDAY EVENING MAINTAIN  
OUR CONCERNS FOR FLASH FLOODING AND RISES ON LOCAL RIVERS UNTIL  
PRECIPITATION FINALLY EXITS THE WESTERN SLOPE WEDNESDAY NIGHT.  
 
RFC GUIDANCE MAINTAINS A SECOND PEAK AT SEVERAL SITES, PEAKING  
AROUND MIDNIGHT DUE TO WEDNESDAY'S PRECIPITATION. FORTUNATELY,  
WATER LEVELS ARE NOT ANTICIPATED TO EXCEED PREVIOUS HIGH WATER  
MARKS. THAT BEING SAID, LOCALIZED FLOODING AND FLASH FLOODING  
CONTINUE TO POSE A THREAT TO OUR SOUTHWESTERN COLORADO  
COMMUNITIES UNTIL REMNANT MOISTURE FROM HURRICANE POLO AND THE  
CLOSED LOW COMPLETELY EXIT OUR REGION.  
 
 
   
GJT WATCHES/WARNINGS/ADVISORIES  
 
CO...FLOOD WATCH THROUGH LATE TONIGHT FOR COZ017-020>022.  
FLOOD WATCH THROUGH LATE WEDNESDAY NIGHT FOR COZ018-019-023.  
UT...FLOOD WATCH THROUGH LATE TONIGHT FOR UTZ022-028-029.  
 
 
 
 
 
DISCUSSION...GF/TGJT  
AVIATION...TGJT  
HYDROLOGY...ERW  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab CO Page
The Nexlab UT Page
Main Text Page