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000
FXUS65 KBOU 161529
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
929 AM MDT THU MAY 16 2013

.UPDATE...SHORT WAVE HAS EXITED THE AREA BUT ENOUGH MOISTURE AND
INSTABILITY BEHIND THE WAVE TO INITIATE A TSTM OVER FORT MORGAN
IN THE LAST FEW MINUTES. OVERALL FORECAST LOOKS ON TRACK. HAVE
NUDGED THE POPS UPWARD IN THE MOUNTAINS THIS AFTN. A FAIRLY
UNIFORM W-NWLY FLOW ALOFT IS PROGGED FOR THIS AFTN....SOME OF
WHICH WILL SHOULD MIX DOWN TO THE SURFACE. CAPES IN THE DENVER
AREA ARE PROGGED TO BE AROUND 400 J/KG WITH THE LOWER LEVELS
DRYING OUT. AS A RESULT...HIGH BASED ISOLATED TSTMS WITH GUSTY
OUTFLOW WINDS TO 35 KTS THE MAIN BIPRODUCT OF THE STORMS. THE PW
VALUES ARE HIGHER FURTHER EAST. EAST OF A STERLING TO AKRON
LINE...AN ISOLATED SEVERE THUNDERSTORM POSSIBLE WITH WIND GUSTS TO
60 MPH AND HAIL TO ONE INCH...ALONG WITH BRIEF HEAVY RAINFALL.
STORM MOTIONS WNWLY AT 10-15 KTS THIS AFTN.

&&

.AVIATION...WEAK BOUNDARY PUSHED THROUGH KDEN EARLIER THIS
MORNING...BUT WINDS BACK TO A S-SWLY COMPONENT. LGT WINDS AND
WEAK SFC PRESSURE GRADIENT MAKE IT HARD FOR MDLS TO KEY IN ON A
PREVAILING WIND. COULD SEE WNWLY WINDS MIX DOWN TO THE SFC WITH
THE LOWER LEVELS DRYING OUT THIS AFTN SO WL GO WITH NW WINDS THIS
AFTN IN THE TAF. SOME BOUNDARY LIKELY LINGERING NEAR OR JUST EAST
OF KDEN SO HAVE INCLUDED VCTS AS WELL WITH THE POTENTIAL FOR HIGH
BASED GUSTY OUTFLOW WINDS THIS AFTN. AS A RESULT HAVE ADD A TEMPO
GROUP WITH GUSTS TO 35 KTS IN THE 21-01Z PERIOD.


&&

.PREV DISCUSSION... /ISSUED 407 AM MDT THU MAY 16 2013/

SHORT TERM...A WEAK UPPER LEVEL TROUGH WAS MOVING INTO NORTHEAST
COLORADO EARLY THIS MORNING WITH SCATTERED SHOWERS AND ISOLD TSTMS
OVER THE FAR NERN CORNER. THIS WK UPPER LEVEL TROUGH SHOULD EXIT
AREA BY 18Z. BY AFTN THE FLOW ALOFT WILL BE MAINLY ZONAL. LATEST
RAP IS SHOWING CAPES BLO 500 J/KG OVER THE HIGHER TERRAIN AND THE
FRONT RANGE HOWEVER OVER THE FAR NE PLAINS CAPES ARE FCST AOA 1000
J/KG. LATEST RAP SHOWS A WK BNDRY SETTING UP FM A STERLING TO
AKRON LN WHICH COULD ACT AS A FOCUS FOR STRONGER TSTM DEVELOPMENT
BY LATE AFTN INTO THE EARLY EVENING HOURS. OVERALL SHEAR WILL BE
BETTER THIS AFTN IN THIS AREA SO THERE COULD BE AN ISOLD MARGINAL
SVR STORM OR TWO. ELSEWHERE THERE WILL BE SOME WDLY SCT CONVECTION
IN THE MTNS...FOOTHILLS AND OVER THE PALMER DIVIDE. AS FOR HIGHS
850-700 MB TEMPS ARE 2-3 DEGREES WARMER THAN WED SO AFTN HIGHS
SHOULD RISE INTO THE 80S OVER NERN CO.  FOR TONIGHT LOOKS LIKE
MOST CONVECTION SHOULD END BY EARLY EVENING AS SEE NOTHING TO KEEP
IT GOING AFTER SUNSET.

LONG TERM...AFTER A DRY AND WARM DAY ON FRIDAY IT LOOKS LIKE THE
REST OF THE FORECAST PERIOD WILL BE COOL AND SOMEWHAT UNSETTLED.
INITIALLY...DRY AND WARM SOUTHWESTERLY FLOW ALOFT WILL PREVAIL
FRIDAY...BRINGING ANOTHER EARLY TASTE OF SUMMER TO THE STATE.
SATURDAY WILL BE A TRANSITIONAL DAY AS AN UPPER TROUGH SETTLES
OVER THE NORTHWEST QUARTER OF THE NATION WITH COLORADO COMING
UNDER THE LEADING EDGE OF THE ADVANCING MOISTURE AND COOLER
TEMPERATURES ALOFT. TROUGHINESS WILL THEN REMAIN OVER THE FORECAST
AREA THROUGH MONDAY NIGHT AND TUESDAY. WEAK DYNAMIC LIFT
ASSOCIATED WITH THE UPPER TROUGH WILL BE OVER THE STATE FOR
SEVERAL DAYS WITH INEVITABLE SHORT WAVE DISTURBANCES MOVING
THROUGH THE TROUGH AT TIMES. ALL THIS SHOULD COMBINE WITH DAILY
HEATING TO PRODUCE ROUNDS OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS. AT LOWER LEVELS...IT APPEARS THAT THE SURFACE LOW
WILL REMAIN FAR ENOUGH EAST TO KEEP GULF MOISTURE MORE IN KANSAS
THAN IN EASTERN COLORADO. STILL ENOUGH MOISTURE SHOULD BE AROUND
FOR LIGHT TO MODERATE PRECIPITATION AT TIMES EACH DAY.
TEMPERATURES WILL GET PROGRESSIVELY COOLER THROUGH MONDAY AND THEN
BEGIN WARMING TUESDAY AND WEDNESDAY AS THE UPPER TROUGH FINALLY
MOVES OUT OF STATE AND AN UPPER RIDGE MOVES IN FROM THE WEST.

WITHOUT STRONG DYNAMICS OR ANY APPRECIABLE JET STREAM WINDS...IT
DOES APPEAR THAT THUNDERSTORMS THROUGH THE WEEKEND WILL LACK
ORGANIZATION WHICH WILL LIMIT THE POTENTIAL FOR SEVERE WEATHER. ON
THE OTHER HAND...STORM MOTIONS COULD BE SLOW AT TIMES MAKING
LOCALIZED HEAVY RAIN POSSIBLE...ESPECIALLY IF ANY GULF MOISTURE
SNEAKS IN FROM THE EAST.

AVIATION...COULD SEE AN ISOLD TSTM OR TWO THIS AFTN IN THE
22Z-01Z PERIOD ESPECIALLY SOUTH OF DIA SO FOR NOW WILL KEEP NEXT
TAF VOID OF TSTMS. WINDS EARLY THIS MORNING WERE DRAINAGE. BY MID
TO LATE MORNING THE NAM AND RAP SHOW WINDS RATHER LIGHT AND
VARIABLE AROUND 5 KTS. BY EARLY AFTN THE RAP HAS THE WINDS ESE AND
THEN MORE SSW BY 21Z. MEANWHILE THE NAM HAS THE WINDS BECOMING WNW
BY 18Z AND KEEPS THEM THAT WAY THRU 00Z. AT THIS POINT NOT SURE
WHICH WAY TO TREND THEM. WITH WLY MID LVL FLOW OUTFLOW BOUNDARIES
FM CONVECTION IN THE FOOTHILLS COULD TURN THE WINDS MORE WNW BY
21Z SO WILL FOLLOW NAM FOR NOW. BY EARLY THIS EVENING WINDS SHOULD
GRADUALLY BECOME DRAINAGE AFTER SUNSET.

HYDROLOGY...THERE WILL BE SOME WIDELY SCATTERED HIGHER BASED
THUNDERSTORMS THIS AFTERNOON NR THE BURN AREAS HOWEVER RAINFALL
AMOUNTS SHOULD BE UNDER A QUARTER INCH.

&&

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

$$

SHORT TERM...COOPER
LONG TERM....DANKERS
AVIATION...COOPER