Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 280339
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
939 PM MDT SUN JUL 27 2014

.UPDATE...
ISSUED AT 938 PM MDT SUN JUL 27 2014

ISOLATED T-STORMS CONTINUE TO PULSE UP THIS EVENING AT THE
INTERSECTION OF OUTFLOW BOUNDARIES...MOST NOTABLY ACROSS NORTHWEST
ADAMS...SOUTHERN WELD AND SOUTHWEST MORGAN COUNTIES. A SECOND
LARGER AREA OF STORM ACTIVITY ACROSS EASTERN ELBERT AND EASTERN
ARAPAHOE...SOUTHWEST WASHINGTON AND NORTHERN LINCOLN COUNTIES
CONTINUES ITS VERY SLOW EASTWARD MIGRATION. KFTG VAD WIND
PROFILER CURRENTLY INDICATES 10-15KT SELY SFC-12K FT AGL
WINDS...AND ONLY 5-20KT NWLY 15K-28K FT AGL WINDS OVER DENVER.
REASON FOR THE SLOW STORM MOTIONS THIS EVENING. INTEGRATED
PRECIPITABLE WATER AMOUNTS CONTINUE TO CLIMB THIS EVENING WITH
IMPRESSIVE PW VALUES OF 1.38 INCH AT BOULDER AND 1.53 INCH AT
PLATTEVILLE. HOWEVER IN THE PAST HOUR HAVE NOTICED A DECLINE IN
STORM INTENSITIES AND COVERAGE. JUST UPDATED POP AND WEATHER
GRIDS TO REFLECT THIS DECREASE IN ACTIVITY. SHOULD SEE MOST IF NOT
ALL OF THESE STORMS ENDING BY MIDNIGHT...EVEN WITH ALL OF THE
ATMOSPHERIC MOISTURE AROUND. HOWEVER THE PRESENCE OF THIS
MOISTURE AND A PERSISTENT LIGHT EAST-SOUTHEAST LOW-LEVEL FLOW
SHOULD AGAIN RESULT IN AREAS OF LOW CLOUDS AND POSSIBLY PATCHY FOG
TOWARDS DAWN...MAINLY UP ALONG THE FRONT RANGE.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 210 PM MDT SUN JUL 27 2014

SCATTERED THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS THE
MOUNTAINS... FOOTHILLS AND FRONT RANGE URBAN CORRIDOR THROUGH MID
EVENING. A SOUTHEAST LOW LEVEL FLOW HAS PUSHED DEW POINTS INTO
UPPER 50S TO LOWER 60S ALONG THE FRONT RANGE WITH PRECIPITABLE
WATER VALUES JUST ABOVE AN INCH. HEAVY RAIN WILL BE POSSIBLE FROM
THE STORMS WITH ONE INCH POSSIBLE IN 20 TO 30 MINUTES. SEVERE
THREAT IS LOW DUE TO LIMITED SHEAR AND CAPES LESS THAN A 1000
J/KG. THOUGH CAN`T TOTALLY RULE ONE OUT EITHER. THE FAR NORTHEAST
PLAINS WILL BE TOO DRY AND STABLE FOR STORMS.

EXPECT THE STORMS TO DIE OFF BY MIDNIGHT AS THE AIRMASS
STABILIZES. LOWS WILL BE SIMILAR TO LAST NIGHT WITH LOWS IN THE
UPPER 50S TO LOWER 60S. EXPECT LOW CLOUDS AND PERHAPS PATCHY FOG
EARLY MONDAY MORNING BECAUSE OF THE MOIST AIRMASS AND COOL
TEMPERATURES.

FOR MONDAY...A MOIST AIRMASS WILL REMAIN IN PLACE. PRECIPITABLE
WATER VALUES WILL BE CLOSE TO TODAY`S VALUES WITH A LITTLE OVER
AN INCH ALONG THE FRONT RANGE URBAN CORRIDOR. THE MORNING MAY
START OFF WITH LOW CLOUDS AGAIN BECAUSE OF THE MOISTURE. HIGHS ARE
EXPECTED TO BE IN THE LOWER TO MID 80S...THOUGH MAY BE A STRUGGLE
TO REACH THEM AGAIN BECAUSE OF THE CLOUDS. USING DEWPOINTS IN THE
MID 50S AND TEMPERATURES IN THE LOWER 80S YIELD CAPES OF 500-1000
J/KG. THIS AND LIMITED SHEAR WILL KEEP THE THREAT FOR SEVERE
WEATHER LOW...ALTHOUGH AN ISOLATED STRONG WIND GUST WILL BE
POSSIBLE. MAIN THREAT WILL BE HEAVY RAIN AGAIN WITH ONE INCH
POSSIBLE IN 20 TO 30 MINUTES FROM THE STRONGER STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 210 PM MDT SUN JUL 27 2014

.LONG TERM...WEST-NORTHWESTERLY FLOW ALOFT WILL DOMINATE FOR THE CWA
MONDAY NIGHT THROUGH TUESDAY. THE UPPER RIDGE CENTER WILL MOVE
SOUTHWESTWARD ON TUESDAY NIGHT WITH A WEAK UPPER LOW TO MOVE DOWN
THE BACK SIDE OF THE MEAN TROUGH OVER EASTERN NORTH AMERICA
TUESDAY NIGHT THROUGH WEDNESDAY EVENING. THE QG VERTICAL VELOCITY
FIELDS STILL SHOW WEAK UPWARD SYNOPTIC SCALE MOTION MONDAY NIGHT
THROUGH WEDNESDAY. THE BOUNDARY LAYER WINDS HAVE AN EASTERLY
COMPONENT TO THEM FROM MONDAY NIGHT THROUGH WEDNESDAY EVENING. IT
IS MOSTLY NORTHEAST TO DUE EASTERLY. A COOLER AIR MASS IS PROGGED
TO MOVE IN ON WEDNESDAY. MOISTURE IS UBIQUITOUS THROUGH THE PERIODS
...ESPECIALLY FORM TUESDAY MORNING INTO WEDNESDAY AFTERNOON. THE
PRECIPITABLE WATER VALUES OVER THE FOOTHILLS AND PLAINS ARE IN THE
0.90 TO 1.50 INCH RANGE FROM MONDAY NIGHT INTO MID DAY WEDNESDAY
BEFORE THEY DECREASE SLIGHTLY THROUGH WEDNESDAY NIGHT. THE LOW
LEVEL DEW POINTS ARE PROGGED IN THE MID 50S TO MID 60S F FOR THE
FOOTHILLS AND PLAINS MONDAY NIGHT INTO WEDNESDAY AFTERNOON. IT IS
PRETTY MOIST. FLOODING IS POSSIBLE DURING THAT PERIOD. THE QPF
FIELDS SHOW SOME MEASURABLE RAINFALL MONDAY EVENING. THE PERIOD
FROM TUESDAY AFTERNOON THROUGH WEDNEDAY AFTERNOON HAS SIGNIFICANT
AMOUNTS PROGGED ON THE ALL THE MODELS FOR THE WESTERN THREE-
QUARTERS OF THE CWA. WEDNESDAY NIGHT HAS LITTLE. THERE IS FAIR
CAPE OVER MOST AREAS MONDAY EVENING...WITH HIGHER VALUES AND
BETTER COVERAGE TUESDAY AFTERNOON THROUGH TUESDAY EVENING. BY
WEDNESDAY AFTERNOON...THE CAPE MINIMAL IS BEHIND THE FRONT. THERE
WILL STILL LIKELY BE STRATIFORM TYPE PRECIPITATION. FOR POPS...
WILL KEEP "CHANCE"S GOING MONDAY EVENING. FROM TUESDAY AFTERNOON
THROUGH WEDNESDAY AFTERNOON WILL GO WITH 50-70%S FOR THE CWA.
WILL DECREASE THEM WEDNESDAY NIGHT. FOR TEMPERATURES...TUESDAY`S
HIGHS ARE 1-3 C COOLER THAN MONDAY`S. WEDNESDAY`S HIGHS ARE
ANOTHER 2-5 C COOLER THAN TUESDAY`S. FOR THE LATER DAYS...THURSDAY
THROUGH SUNDAY...THE UPPER RIDGE IS ORIENTED NORTH-SOUTH AND THE
AXIS BEGINS MOVING EASTWARD FROM THE INTER MOUNTAIN WEST. ON
FRIDAY SATURDAY AND SUNDAY...THE UPPER RIDGE AXIS IS JUST WEST OF
THE COLORADO/UTAH BORDER. MOISTURE DECREASES SOMEWHAT...BUT NOT
TOTALLY. TEMPERATURES STAY BELOW SEASONAL NORMALS THANKS TO THE
NORTHWESTERLY FLOW ALOFT.

&&

.AVIATION...(FOR THE TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 938 PM MDT SUN JUL 27 2014

THE VERY SLOW MOVING THUNDERSTORM IMMEDIATELY NORTHWEST THROUGH
NORTHEAST OF DENVER INTERNATIONAL AIRPORT CONTINUES TO SHOW
SIGNING OF WEAKENING AT THIS TIME. AT THE PRESENT RATE THIS CELL
SHOULD EITHER DISSIPATE OR MOVE EAST OF THE AIRPORT IN THE NEXT
45-60 MINUTES. OTHERWISE THE THREAT OF T-STORMS AT DENVER AREA
TERMINALS WILL CONTINUE TO DECLINE OVER THE NEXT COUPLE OF HOURS
AS THE AMBIENT AIRMASS STABILIZES WITH COOLING. CURRENT TERMINAL
FORECASTS INDICATE LOW CIGS AFTER 10Z TONIGHT IN RESPONSE TO THE
VERY MOIST UPSLOPE FLOW IN PLACE. MODELS NOT INDICATING ANY
FOG IN THE METRO AREA...JUST A STRATUS DECK ROUGHLY FROM 12Z-15Z
OR SO TOMORROW MORNING. MODEL SOUNDINGS AND CROSS SECTIONS DO NOT
INDICATE A CLOUD LAYER AS LOW OR AS THICK AS THE ONE THIS MORNING.
SO MAY SEE AN EARLIER BREAKOUT.

&&

.HYDROLOGY...
ISSUED AT 938 PM MDT SUN JUL 27 2014

EVENING STORMS WILL CONTINUE TO DECLINE IN BOTH COVERAGE AND
INTENSITY. RAINFALL RATES OF LESS THAN 0.25 INCH PER HOUR ARE ALL
THAT IS EXPECTED WITH STORMS IN THE THE DENVER/BOULDER CWA FOR
THE REMAINDER OF THE EVENING.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...BAKER
SHORT TERM...MEIER
LONG TERM...RJK
AVIATION...BAKER
HYDROLOGY...BAKER


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