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000
FXUS65 KBOU 191552
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
952 AM MDT WED JUN 19 2013

.UPDATE...ONLY SHALLOW MOISTURE LEFT BEHIND PER 12Z KDNR
SOUNDING AND LATEST PW TRENDS SHOWING ABOUT 0.25 INCH DECREASE.
LOW LEVEL MOISTURE WILL SCOUR OUT TO THE EAST THIS AFTERNOON BUT
WILL LIKELY HOLD IN AREAS ALONG/EAST OF A LINE FROM STERLING TO
AKRON. WILL KEEP A LOW THREAT OF THUNDERSTORMS THERE...BUT WITH
SURFACE BASED CAPES OVER 2500 J/KG ANY STORMS THAT FIRE COULD
EASILY BECOME SEVERE.  DRY CONDITIONS ELSEWHERE.

FIRE DANGER ON TRACK TO INCREASE WITH GUSTY SOUTHWEST WINDS
DEVELOPING LATER THIS MORNING AND CONTINUING THROUGH THE
AFTERNOON. HIGH MOUNTAIN VALLEYS WILL BE MOST PRONE DUE TO
COMBINATION OF VERY LOW RH...WINDS...AND DRY FUELS...SO WILL
CONTINUE THE RED FLAG WARNINGS THERE. HELD OFF ON THE PALMER
DIVIDE FOR NOW TODAY CONSIDERING LAST NIGHTS RAIN SHOULD DELAY
POSSIBLE RED FLAG CONDITIONS UNTIL THURSDAY.

&&

.AVIATION...FORECAST ON TRACK. SOUTHERLY WINDS SHOULD PREVAIL
WITH GUSTS AROUND 25 KTS POSSIBLE THROUGH 00Z-02Z. THERE A DENVER
CYCLONIC CONVERGENCE ZONE DEVELOPING NORTH OF KDEN...WHICH WOULD
HAVE A BETTER CHANCE OF KEEPING LIGHTER WINDS AT KBJC. KDEN COULD
SEE AN EVENTUAL TURN TO A MORE WESTERLY OR NORTHERLY DIRECTION IF
BOUNDARY SINKS THIS WAY SO WILL MONITOR THROUGH THE AFTERNOON. ANY
STORMS WILL BE EAST OF THE FRONT RANGE AIRPORTS.

&&

.PREV DISCUSSION... /ISSUED 333 AM MDT WED JUN 19 2013/

SHORT TERM...AN UPPER LEVEL LOW OVER THE PACIFIC NORTHWEST AND A
RIDGE OVER THE CENTRAL PLAINS WILL RESULT IN A SOUTHWEST FLOW ALOFT
OVER COLORADO. THIS WILL TRANSPORT WARM AND VERY DRY DESERT AIR INTO
THE STATE TODAY. HIGHS WILL INCREASE INTO THE LOWER 90S THIS
AFTERNOON. AIRMASS WILL BE VERY DRY WITH MOST LOCATIONS WEST OF
INTERSTATE 25 SEEING SINGLE DIGIT RELATIVE HUMIDITIES DURING THE
AFTERNOON. THIS WILL INCREASE THE FIRE DANGER. SOUTHWEST WINDS WILL
INCREASE DURING THE AFTERNOON AS THE AIRMASS MIXES UP TO 500 MB.
EXPECT WINDS OF 15 TO 30 MPH OVER THE HIGHER TERRAIN THIS AFTERNOON.
WILL ISSUE A RED FLAG WARNING FOR THE MOUNTAIN VALLEYS INCLUDING
PARK COUNTY.

A SURFACE TROUGH/DRY LINE WILL BE OVER EASTERN COLORADO. TO THE WEST
OF IT AND FOR MOST OF THE AREA...DRIER AIR MIXING DOWN WILL CAUSE
DEW POINTS TO PLUMMET INTO THE TEENS AND 20S. EAST OF IT...DEW
POINTS WILL BE ABLE TO STAY IN THE 50S PRODUCING CAPES OF 2000 J/KG
OR POTENTIALLY HIGHER. SO IF ANY STORMS CAN FORM AND RAPIDLY
INTENSIFY BEFORE EXITING THE FORECAST AREA...THEY MAY BE ABLE TO
PRODUCE GOLF BALL SIZE HAIL AND DAMAGING WINDS. THIS THREAT WILL BE
OVER FAR EASTERN COLORADO AND INTO NEBRASKA AND KANSAS.

LONG TERM...MODEL KEEP SHOWING A STRONG UPPER CLOSED LOW OVER THE
NORTHWESTERN CORNER OF THE UNITED STATES AND AN UPPER RIDGE OVER
TEXAS INTO THE SOUTHEASTERN STATES THURSDAY THROUGH FRIDAY NIGHT.
OUR FORECAST AREA STAYS IN 30-50 KNOT SOUTHWESTERLY FLOW ALOFT ALL
FOUR PERIODS. THE SYNOPTIC SCALE ENERGY IS NEUTRAL TO WEAK UPWARD
IN NATURE FOR THE CWA THURSDAY THROUGH FRIDAY NIGHT. IN THE LOW
LEVELS...THE MODELS CONTINUE TO SHOW A WEAK COLD FRONT TO MOVE
INTO THE CWA THURSDAY MORNING...WITH EAST-NORTHEASTERLY UPSLOPE
FLOW BEHIND IT THROUGH THURSDAY EVENING. AFTER THAT...NORMAL
DIURNAL WIND PATTERNS ARE PROGGED THROUGH FRIDAY NIGHT. MOISTURE
IS VERY LIMITED THURSDAY AND THURSDAY NIGHT...JUST A BIT IN THE
MID AND UPPER LEVELS LATE IN THE DAY. THE NAM SHOWS A BIT OF LOW
LEVEL MOISTURE OVER THE PLAINS LATE THURSDAY NIGHT...THE GFS DOES
NOT. FRIDAY AND FRIDAY NIGHT LOOK VERY DRY AGAIN...JUST A TAD OF
MID AND UPPER LEVEL MOISTURE LATE IN THE DAY. THE LOW LEVEL DEW
POINT READINGS ARE PROGGED IN THE 20-35 F RANGE FOR MUCH OF THE
CWA THURSDAY AND THURSDAY EVENING. THEY ARE A BIT OVER 40 F OVER
THE NORTHEAST CORNER. LATER THURSDAY NIGHT INTO FRIDAY MORNING
..THE NAM AND GFS BRING 50S F DEW POINTS INTO THE EASTERN TWO-
THIRDS OF THE PLAINS. MODELS PUSH THIS MOISTURE EAST OF THE CWA BY
FRIDAY AFTERNOON...BUT THE NAM BRINGS IN BACK IN FRIDAY NIGHT. AS
PER NORMAL...THE MODELS DO NOT HAVE A HANDLE ON WHERE THE LOW
LEVEL MOISTURE WILL BE. THE ONLY CAPE IS OVER THE EAST AND
NORTHEAST BORDER AREAS BOTH LATE DAY THURSDAY AND LATE DAY FRIDAY.
THE QPF FIELDS HAVE A TAD OF MEASURABLE RAINFALL OVER THE FAR
CORNER...THAT`S IT. THE LAPSE RATE FIELDS HAVE A STRONG MID LEVEL
CAP OVER MUCH OF THE CWA THURSDAY AND THURSDAY NIGHT...THE
EXCEPTION BEING THE FAR EASTERN PLAINS. ON FRIDAY...THERE IS WAY
LESS OF A CAP OVER ALL AREAS. FOR POPS...COULD GO WITH "SLIGHT
CHANCE"S OVER THE FAR EAST BOTH DAYS IF THE MOISTURE WILL BE THERE
..BUT WILL LEAVE THEM OUT THIS UPDATE...BECAUSE I DON`T KNOW.
CONCERNING THE WILDFIRE POTENTIAL...WILL LEAVE THE WATCH GOING
OVER SOUTH PARK AND PALMER RIDGE FOR THURSDAY AFTERNOON AND
EVENING WITH NOTHING CONCLUSIVE IN THE NEW 00Z DATA TO SAY
OTHERWISE. IT`S MARGINAL OVER THE PALMER AS FAR AS WINDS GO...BUT
IS CERTAINLY SHOULD BE DRY ENOUGH. SOUTH PARK`S PROGGED WINDS ARE
SOMEWHAT STRONGER AND IT IS WILL BE DRY THERE AS WELL. FOR
TEMPERATURES...THURSDAY`S HIGHS LOOK 1-2 C COOLER THAN TODAY`S.
FRIDAY`S HIGHS COME BACK UP 1-2 C FROM THURSDAY`S. FOR THE LATER
DAYS...SATURDAY THROUGH TUESDAY...THE FLOW ALOFT STAYS
SOUTHWESTERLY ALL FOUR DAYS. THE UPPER LOW OVER THE NORTHWEST U.S.
IS PROGGED TO FINALLY PUSH EASTWARD SATURDAY AND SATURDAY NIGHT. A
BIT OF ENERGY MAY ACTUALLY GRAZE THE FORECAST AREA SATURDAY
AFTERNOON AND NIGHT. THERE COULD BE ENOUGH MOISTURE AROUND FOR
SLIGHT POPS LATE DAY SATURDAY AND LATE DAY SUNDAY. TEMPERATURES
ARE ABOVE NORMALS.


AVIATION...SOUTHERLY WINDS WILL CONTINUE THROUGH THE MORNING AND
BECOME GUSTY THIS AFTERNOON WITH GUSTS TO 25 KNOTS. THERE IS A
DENVER CYCLONE TO THE NORTHWEST OF DENVER...SO CONFIDENCE IN WIND
DIRECTION IS ON THE LOW SIDE. AS THE CYCLONE MOVES EAST...WINDS MAY
TURN TO THE WEST OR NORTHWEST FOR TIME BETWEEN 12-18Z. TOO DRY TODAY
FOR STORMS...AND JUST EXPECT A FEW MID TO HIGH CLOUDS.

HYDROLOGY...NO CONCERNS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY
EVENING FOR COZ214-241.

RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ211-213-214.

&&

$$

SHORT TERM...BARJENBRUCH
LONG TERM....RJK
AVIATION...BARJENBRUCH