391  
FXUS65 KGJT 190630  
AFDGJT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND JUNCTION CO  
1230 AM MDT SUN JUL 19 2026  
   
KEY MESSAGES  
 
- SHOWERS AND THUNDERSTORMS WILL CONTINUE EACH AFTERNOON AND  
EVENING THROUGH AT LEAST EARLY NEXT WEEK.  
 
- MAIN THREATS WITH THESE STORMS INCLUDE LIGHTNING, LOCALIZED  
HEAVY RAINFALL, AND GUSTY OUTFLOW WINDS (35-45 MPH).  
 
- THESE STORMS HAVE THE ABILITY TO PRODUCE FLASH FLOODING AND  
DEBRIS FLOWS IN VULNERABLE TERRAIN, INCLUDING AREAS NEAR AND  
DOWNSTREAM OF BURN SCARS.  
 
 
   
DISCUSSION  
 
ISSUED AT 1004 PM MDT SAT JUL 18 2026  
 
A FEW SHOWERS AND THUNDERSTORMS ARE DRIFTING SOUTHWESTWARD IN  
EASTERN UT THIS EVENING. THIS LEFTOVER CONVECTION WILL CONTINUE  
TO DECAY. STRATIFORM STORM DEBRIS WILL STICK AROUND IN SOME  
FASHION INTO THE MORNING HOURS. THIS IS ONLY WORTH MENTIONING  
FOR ITS POTENTIAL TO TEMPER CONVECTIVE INITIATION ON SUNDAY  
MORNING. BUT...IT'S NOT IF, BUT RATHER WHEN WILL STORMS FIRE  
OFF AGAIN ON SUNDAY. LITTLE CHANGE IN THE AIR MASS WILL SPELL  
OUT A RINSE AND REPEAT FORECAST SUNDAY AFTERNOON. THE HIGH DOES  
AMPLIFY SOME, SO AFTERNOON HIGHS LOOK TO TREND UP WHERE CLOUD  
COVER AND SHOWERS DON'T IMPEDE HEATING. A FEW HOT SPOTS COULD  
GET SOME COOLING BY EVENING GIVEN THE LIKELY OUTFLOWS PINBALLING  
AROUND THE REGION. GENEROUS CAPE ON FORECAST SOUNDINGS, ALONG  
WITH RICH PWAT VALUES WILL ENSURE THUNDERSTORMS RETAIN THEIR  
ABILITY TO PRODUCE HEAVY RAINFALL RATES, SMALL HAIL, GUSTY  
WINDS, AND THE COLLATERAL IMPACTS THAT COME ALONG, NAMELY FLASH  
FLOODING. STORM MOTIONS WILL BE SIMILAR TO TODAY, PUSHING EAST  
TO WEST AGAIN SUNDAY AFTERNOON.  
 
WITH HIGH PRESSURE FIRMLY ENTRENCHED OVER THE WEST, TEMPERATURES  
WILL CONTINUE TO TREND A FEW DEGREES OVER AVERAGE THE FIRST HALF  
OF THE WORK WEEK. DAILY SHOWERS AND THUNDERSTORMS COULD KEEP  
HOPES UP FOR COOLER EVENINGS, ESPECIALLY WHERE WE CAN INCREASE  
SHOWER COVERAGE ON THE MOUNTAINS. UNFORTUNATELY, WE ARE STILL  
WAITING FOR BETTER COVERAGE OF MOISTURE TO DELIVER ON THAT  
PROMISE. MODEL SOUNDINGS DO INCREASE PWAT VALUES TUESDAY AND  
WEDNESDAY, AS WELL AS RETAIN GOOD FORCING. A SHIFT IN THE HIGH'S  
POSITION LOOKS INEVITABLE TOO. THIS WILL SHIFT STORM MOTIONS  
AND MOISTURE TRANSPORT SOMETIME AROUND WEDNESDAY TOO. MODELS  
BACK OFF ON TEMPERATURES MID WEEK, STRIPPING SOME OF THE TRIPLE  
DIGITS OUT OF THE FORECAST. DETERMINISTIC MODELS HINT AT THE  
CENTER OF THE HIGH SHIFTING EAST NEXT WEEKEND. STILL TOO EARLY  
IN THE GAME FOR THAT, BUT THAT WILL REMAIN A PIVOTAL FORECAST  
DETAIL AS THE WEEK WEARS ON.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z MONDAY/  
 
ISSUED AT 1204 AM MDT SUN JUL 19 2026  
 
A FEW SHOWERS AND THUNDERSTORMS ARE PUSHING SOUTHWEST THROUGH  
SOUTHEASTERN UTAH THAT WILL MOVE OUT OF THE REGION OVER THE NEXT  
FEW HOURS. LOOK FOR ISOLATED SHOWERS AND THUNDERSTORMS TO  
DEVELOP OVER THE HIGHER TERRAIN AFTER 15Z BECOMING WIDELY  
SCATTERED AFTER 18Z. SOME STORMS WILL WORK DOWN INTO THE LOWER  
VALLEYS THROUGH THE AFTERNOON, WITH STORMS DIMINISHING AFTER  
00Z BECOMING MORE STRATIFIED SHOWERS AFTER 03Z, MUCH LIKE THIS  
EVENING. THE MAIN THREATS WITH CONVECTION WILL BE LIGHTNING,  
GUSTY OUTFLOWS (30-40KTS), AND BRIEF PERIODS OF MVFR IN HEAVY  
RAINFALL. OTHERWISE, EXPECT VFR CONDITIONS WITH LIGHT WINDS.  
 
 
   
HYDROLOGY  
 
ISSUED AT 1012 AM MDT SAT JUL 18 2026  
 
ANOMALOUS MOISTURE HAS BECOME ESTABLISHED ACROSS PORTIONS OF  
EASTERN UTAH AND WESTERN COLORADO. RAINFALL RATES OF 1-2 INCHES  
PER HOUR WILL BE POSSIBLE WITH THE STRONGER STORMS. THESE RATES  
COULD LEAD TO FLASH FLOODING AND DEBRIS FLOWS ESPECIALLY OVER  
RECENT BURN SCARS.  
 
STORMS OVER THE LAST FEW DAYS HAVE HELPED PRIME LOWER LEVELS OF  
THE ATMOSPHERE AND SATURATE THE GROUND WHERE RAIN WAS OBSERVED.  
SEVERAL LOCATIONS ACROSS SOUTHWEST COLORADO HAVE REPORTED 0.5  
TO 1.0 INCHES OF RAIN WITHIN 30 MINUTES; WHICH IS MORE THAN  
SUFFICIENT TO CREATE ISSUES IN OUR STEEP, ROCKY TERRAIN THAT IS  
ALREADY SUSCEPTIBLE TO FLASH FLOODING. THIS ENVIRONMENT ALSO  
TRIGGERS HEIGHTENED AWARENESS OVER RECENT (OR ACTIVELY BURNING)  
FIRES, DUE TO THE BURNT GROUND'S INABILITY OF ABSORBING MOISTURE  
UNDER HEAVY RAINFALL. AS SUCH, WE CONTINUE TO EMPHASIZE THE  
POTENTIAL FOR FLASH FLOODING AND DEBRIS FLOWS IN THIS REGIME.  
 
AS A REMINDER: KEEP AN EYE ON OUR FORECASTS THROUGH THE END OF  
THE WEEK AND STAY TUNED FOR UPDATED HYDROLOGY ALERTS IF  
VISITING OR IF YOU RESIDE BELOW VULNERABLE TERRAIN TO FLASH  
FLOODING AND/OR DEBRIS FLOWS. STORMS ACROSS THE WEST DEVELOP  
QUICKLY, LEAVING LITTLE ROOM FOR LEAD TIME IN FLASHY TERRAIN.  
 
 
   
GJT WATCHES/WARNINGS/ADVISORIES  
 
CO...NONE.  
UT...NONE.  
 
 
 
 
 
DISCUSSION...LTB  
AVIATION...DB  
HYDROLOGY...TGJT  
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