613  
FXUS65 KPUB 162136  
AFDPUB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PUEBLO CO  
336 PM MDT TUE JUL 16 2019  
   
SHORT TERM
 
(THIS EVENING THROUGH WEDNESDAY)  
ISSUED AT 309 PM MDT TUE JUL 16 2019  
   
..WARMER AND BREEZY WITH FEWER STORMS TOMORROW
 
 
 
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS IS INDICATING  
WEAK TO MODERATE WESTERLY FLOW ALOFT ACROSS THE REGION, WITH THE  
CENTER OF THE LARGE MID LEVEL HIGH IN PLACE ACROSS SOUTHWESTERN NEW  
MEXICO, AS EASTERN PACIFIC ENERGY CONTINUES TO TRANSLATE ACROSS THE  
PACIFIC NORTHWEST THROUGH THE NORTHERN TIER AT THIS TIME. WATER  
VAPOR IMAGERY IS ALSO INDICATING DRIER AIR ACROSS THE DESERT  
SOUTHWEST WORKING INTO THE REGION, WITH BLENDED TOTAL PRECIPITABLE  
WATER IMAGERY INDICATING PWATS OF 0.5 TO TO 0.7 INCHES ACROSS MOST  
OF COLORADO, THOUGH PWATS ARE STILL RUNNING AROUND 1 INCH ACROSS THE  
FAR SOUTHEAST PLAINS. REGIONAL RADARS ARE INDICATING SCATTERED  
SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN, WITH A FEW STORMS  
MOVING EAST ACROSS THE IMMEDIATE ADJACENT PLAINS AT THIS TIME.  
 
CURRENT MODELS AND FORECAST REMAIN CONSISTENT WITH INCREASING  
WESTERLY FLOW ALOFT ACROSS THE REGION THROUGH THE DAY TOMORROW, AS  
EASTERN PACIFIC ENERGY CONTINUES TO TRANSLATE ACROSS THE NORTHERN  
TIER AND THE UPPER HIGH BUILDS BACK INTO THE DESERT SOUTHWEST. THIS  
WILL CONTINUE TO BRING IN MUCH DRIER AIR, NOTED IN CURRENT WATER  
VAPOR IMAGERY ACROSS THE SOUTHERN GREAT BASIN, INTO THE ROCKIES.  
 
FOR TONIGHT, WILL CONTINUE TO SEE A FEW STORMS PUSHING EAST ACROSS  
THE HIGH VALLEYS AND I-25 CORRIDOR THROUGH THE LATE AFTERNOON AND  
EVENING, WITH THE BEST COVERAGE ACROSS THE PIKES PEAK/PALMER DVD AND  
THE RATON MESA. LATEST HIGH RES MODELS INDICATE THAT STORMS WILL  
ONCE AGAIN PUSH EAST ACROSS THE FAR SOUTHEAST PLAINS THROUGH THE  
EVENING HOURS, WHERE BEST LOW LEVEL MOISTURE AND INSTABILITY RESIDE.  
LATEST MODELS DO INDICATE AN EMBEDDED DISTURBANCE LIFTING OUT ACROSS  
THE GREAT BASIN AND INTO THE NORTHERN ROCKIES OVERNIGHT, WHICH COULD  
KEEP A FEW SHOWERS AND STORMS THROUGH THE OVERNIGHT HOURS ACROSS THE  
HIGHER TERRAIN ALONG AND WEST OF THE CONTDVD. OVER NIGHT LOWS WILL  
CONTINUE TO BE AT OR SLIGHTLY ABOVE SEASONAL LEVELS, IN THE MID 50S  
TO MID 60S ACROSS THE PLAINS, AND MAINLY 40S AND 50S ACROSS THE  
HIGHER TERRAIN.  
 
FOR TOMORROW, WESTERLY FLOW INCREASES WITH DRIER AIR EMBEDDED WITHIN  
THE FLOW LEADING TO DECREASING COVERAGE OF STORMS ACROSS THE HIGHER  
TERRAIN, WITH STORMS THAT DO FORM BEING HIGHER BASED, PRODUCING MORE  
WIND THE WETTING RAINS. MODELS ALSO INDICATE INDUCED LEE TROUGHING  
ACROSS THE PLAINS, WITH LOW LEVEL MOISTURE MIXING OUT ACROSS THE I-  
25 CORRIDOR THROUGH THE AFTERNOON. MODELS INDICATING A FEW STORMS  
DEVELOPING ACROSS THE MTS, THE PALMER DVD AND RATON MESA EARLY IN  
THE AFTERNOON, ALONG WITH A FEW POSSIBLE STORMS INITIATING ALONG THE  
LEE TROUGH ACROSS THE FAR SOUTHEAST PLAINS. STORM THREATS TOMORROW  
WILL CONTINUE TO BE LIGHTNING AND GUSTY OUTFLOW WINDS, WITH A FEW  
STRONGER STORMS POSSIBLE ACROSS THE FAR SOUTHEAST PLAINS. WITH THE  
WESTERLY DOWNSLOPE FLOW, SHOULD SEE TEMPERATURES PUSHING NEAR RECORD  
LEVELS WITH HIGHS IN THE 90S TO LOWER 100S ACROSS THE LOWER  
ELEVATIONS, IN THE 70S AND 80S ACROSS THE HIGHER TERRAIN AND MAINLY  
50S AND 60S AT THE PEAKS. RECORDS FOR JULY 17TH ARE 92F AT ALS SET  
IN 2005, 96F AT COS SET IN 2010 AND 105F AT PUB SET IN 2003. THE  
WARM TEMPERATURES, DRIER AIR AND BREEZY CONDITIONS WILL ALSO LEAD TO  
NEAR CRITICAL FIRE WEATHER CONDITIONS ACROSS PORTIONS OF THE AREA  
TOMORROW AFTERNOON.  
   
LONG TERM
 
(WEDNESDAY NIGHT THROUGH TUESDAY)  
ISSUED AT 309 PM MDT TUE JUL 16 2019  
 
THURSDAY - FRIDAY...  
 
A BROAD RIDGE WILL EXTEND FROM ARIZONA TO THE SOUTHEAST US COAST,  
WITH AN UPPER JET AND PERIODIC DISTURBANCES OVER THE FAR NORTHERN  
US. COLORADO WILL BE ORIENTED UNDER THE NORTHWEST PORTION OF THE  
RIDGE, WITH WEAK WESTERLY FLOW ALOFT. A FEED OF DRY AIR WILL  
CONTINUE OVER THE STATE LEADING TO SLIGHTLY BELOW NORMAL TPW  
VALUES. GIVEN LACK OF MOISTURE AND FORCING, NO PRECIPITATION IS  
EXPECTED ACROSS THE FORECAST AREA. THE MAIN STORY WILL BE THE  
HEAT, WITH TEMPERATURES ACROSS THE PLAINS EXPECTED TO RISE INTO  
THE 100 - 105 DEGREE RANGE, AND THOSE ACROSS THE HIGH VALLEYS IN  
THE MID 80S TO MID 90S. THE VERY WARM TEMPERATURES AND DRY  
CONDITIONS WILL DRIVE SURFACE RH VALUES DOWN TO 10-15%, OR  
CRITICAL LEVELS, DURING EACH AFTERNOON ACROSS THE PLAINS AND  
VALLEYS. DESPITE DEEP VERTICAL MIXING, WINDS AT THE SURFACE SHOULD  
GENERALLY REMAIN SUB-CRITICAL CONSIDERING WEAK FLOW ALOFT AND A  
LACK OF SURFACE PRESSURE GRADIENT. THEREFORE, CRITICAL FIRE  
WEATHER CONDITIONS ARE NOT EXPECTED.  
 
SATURDAY - SUNDAY...  
 
THE BROAD RIDGE REMAINS IN PLACE OVER THE SOUTHERN HALF OF THE  
US, WITH ATTENTION TURNING TO A POTENTIALLY POTENT SHORTWAVE  
TROUGH ADVANCING EAST ACROSS THE NORTHERN ROCKIES IN THE SATURDAY  
NIGHT THROUGH SUNDAY TIMEFRAME. THERE IS CONSIDERABLE MODEL  
UNCERTAINTY WITH THE EVOLUTION OF THIS SYSTEM THAT WILL INFLUENCE  
SOUTHERN COLORADO WEATHER. THE LAST COUPLE DAYS OF GFS RUNS HAVE  
HAD A POTENT WAVE SENDING A SURFACE COLD FRONT DOWN THE EASTERN  
COLORADO PLAINS SATURDAY EVENING WITH POST-FRONTAL SURFACE WINDS  
WINDS TURNING EASTERLY. THIS WOULD LEAD TO A RAPID INCREASE IN  
MOISTURE AND CONSIDERABLE SHOWER AND THUNDERSTORM COVERAGE ACROSS  
MUCH OF THE CWA BY SUNDAY AFTERNOON/EVENING, AND MUCH COOLER  
TEMPERATURES SUNDAY. THE LAST COUPLE OF ECMWF RUNS HAVE HAD A  
WEAKER WAVE, A SUBTLE NORTHERLY SURGE, A SLOWER INCREASE IN  
MOISTURE, LESS PRECIPITATION ON SUNDAY, AND ONLY SLIGHTLY COOLER  
TEMPERATURES ON SUNDAY. FORECAST ENSEMBLES SHOW CONSIDERABLE  
SPREAD WITH THE EVOLUTION OF THE NORTHERN WAVE.  
 
REGARDLESS, IT LOOKS LIKE MOST OF SATURDAY WILL REMAIN DRY ACROSS  
THE FORECAST AREA, WITH AFTERNOON TEMPERATURES SIMILAR TO THOSE  
OF THURSDAY AND FRIDAY. WITH OR WITHOUT THE STRONG NORTHERN WAVE  
AND COLD FRONT, MOISTURE ALOFT SHOULD START TO CREEP UP ON SUNDAY  
AS THE UPPER HIGH BEGINS TO CLOSE OFF NEAR THE CO/NM BORDER,  
SIMILAR TO LAST WEEKS ORIENTATION. THIS WILL LEAD TO AT LEAST  
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS OVER THE HIGH  
TERRAIN BY SUNDAY AFTERNOON AND EARLY EVENING.  
 
GIVEN ALL OF THIS, FORECAST CONFIDENCE IS HIGH THAT PRECIPITATION  
COVERAGE WILL BEGIN TO INCREASE ACROSS THE FORECAST AREA ON  
SUNDAY, BUT EXACT DETAILS, INCLUDING RELATED TO TEMPERATURE  
TRENDS, REMAIN UNCERTAIN.  
 
MONDAY - TUESDAY...  
 
THE UPPER HIGH PRESSURE REMAINS OVER COLORADO, WITH ITS CENTER  
SHIFTING NORTH SLIGHTLY TO WEST-CENTRAL COLORADO BY TUESDAY  
EVENING. THIS ALLOWS INCREASED MID TO UPPER LEVEL MOISTURE TO  
CONTINUE TO STREAM INTO COLORADO. AT THE SAME TIME, LOW LEVEL FLOW  
ACROSS THE EASTERN PLAINS SHOULD REMAIN EASTERLY TO  
SOUTHEASTERLY. THIS PATTERN WILL KEEP TPW NEAR TO SLIGHTLY ABOVE  
NORMAL, YIELDING AFTERNOON THUNDERSTORM DEVELOPMENT OVER THE HIGH  
TERRAIN EACH DAY. STEERING FLOW WILL BE WEAK, SO STORM DEVELOPMENT  
OVER THE PLAINS WILL AGAIN DEPEND OUTFLOW BOUNDARIES EMANATING  
FROM THE WESTERN ACTIVITY. STORM DURING THIS PERIOD HAVE THE  
POTENTIAL TO PRODUCE HEAVY RAINFALL, SO POSE FLASH FLOOD THREAT TO  
BURN SCARS. TEMPERATURES LOOK TO BE NEAR OR SLIGHTLY BELOW TO  
START THE WORK WEEK.  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)  
ISSUED AT 309 PM MDT TUE JUL 16 2019  
 
SIMILAR FORECAST AS THE LAST SEVERAL DAYS, WITH AFTERNOON STORMS  
OVER THE HIGHER TERRAIN SPREADING EAST ACROSS THE ADJACENT PLAINS  
THROUGH THE EARLY EVENING. WITH THAT SAID, VFR CONDITIONS REMAIN  
EXPECTED AT COS, PUB AND ALS OVER THE NEXT 24 HOURS, WITH STORMS  
POSSIBLE AT THE TERMINALS BETWEEN THRU 02Z WEDNESDAY. STORMS WILL BE  
HIGHER BASED, WITH GUSTY OUTFLOW WINDS UP TO 40KTS EXPECTED TO BE  
THE MAIN THREAT, THOUGH LOCALLY HEAVY RAINFALL AND SMALL HAIL WILL  
STILL POSSIBLE WITH THE STRONGER STORMS. LESS CONVECTION WITH BREEZY  
AFTERNOON WESTERLY WINDS EXPECTED AT THE TERMINALS TOMORROW.  
 

 
   
PUB WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...MW  
LONG TERM...LINE  
AVIATION...MW  
 
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