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000
FXUS65 KBOU 111605
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1005 AM MDT TUE JUN 11 2013

.UPDATE...CURRENT FORECAST LOOKS GOOD WITH RECORD HEAT AND
CRITICAL FIRE DANGER/RED FLAG WARNINGS WHERE FUELS ARE
SUFFICIENTLY DRY. ONLY CHANGE WAS TO ADD JUST A SLIGHT CHANCE OF
STORMS OVER THE NORTHEAST CORNER DUE TO LOW LEVEL MOISTURE/
CONVERGENCE NOTED THERE THIS AFTERNOON/EARLY EVENING.
HOWEVER...DRY AIR ENTRAINMENT ALOFT WOULD LIKELY LIMIT UPDRAFT
STRENGTH/STORM DEVELOPMENT.

&&

.AVIATION...GUSTY SOUTHWEST WINDS WERE JUST DEVELOPING AT KDEN AND
KAPA THIS MORNING AND WINDS WILL CONTINUE TO STRENGTHEN THROUGH
THE AFTERNOON AND TURN MORE WESTERLY. CROSSWIND LIMITATIONS WILL
LIKELY OCCUR BY 19Z-21Z AS WIND GUSTS APPROACH 30-35 KTS AND WIND
SWITCHES TO 250-270 DEGREES. WINDS WILL LIKELY TURN MORE 280-300
BY 22Z-00Z WITH CROSSWIND LIMITS IN PLAY TIL 02Z WHEN WINDS RELAX.

&&

.PREV DISCUSSION... /ISSUED 423 AM MDT TUE JUN 11 2013/

SHORT TERM...SOUTHWEST WINDS ALOFT BECOMING WESTERLY TODAY BEHIND
THE SHORTWAVE WITH MUCH DRIER AIR ALOFT MOVING IN. WITH LOTS OF
SUNSHINE AND ONLY SHALLOW INVERSIONS WE SHOULD MAKE THE MOST OF
THE AIRMASS...WITH TEMPERATURES ABOUT THE SAME AS YESTERDAY
DESPITE SLIGHT COOLING ALOFT. GOOD MIXING WILL ALLOW THE WIND TO
SURFACE AND HELP HUMIDITIES TO DROP INTO THE 5-10 PERCENT RANGE
THIS AFTERNOON. ALL OF THIS WAS PRETTY WELL COVERED ALREADY...I
BUMPED THE AFTERNOON WINDS UP SLIGHTLY AND NUDGED THE DEW POINTS
DOWN A LITTLE MORE TOWARD THE NAM MOS GUIDANCE. FORECAST FIRE
DANGER RATING FOR THE NORTHERN FOOTHILLS BASED ON OUR GRIDS PUSHES
INTO THE VERY HIGH CATEGORY TODAY AS THE FUELS CONTINUE TO
DRY...SO I WILL ADD THAT AREA TO THE RED FLAG WARNING. AREAS IN
THE HIGHER MOUNTAINS AND ON THE PLAINS NORTH OF INTERSTATE 70 ARE
STILL REPORTED TO BE GREEN ENOUGH TO NOT NEED A RED FLAG
WARNING...BUT STILL AN ELEVATED RISK TODAY.

STRONGER COLD ADVECTION TONIGHT WILL KEEP WINDS UP IN THE EVENING
AS THEY SHIFT TO A MORE NORTHERLY DIRECTION. WINDS SHOULD DIMINISH
ENOUGH LATER UNDER CLEAR SKIES TO ALLOW TEMPERATURES TO
DROP...LOWERED OUR FORECAST LOWS A COUPLE OF DEGREES...NEAR THE
MOS GUIDANCE. FIRE DANGER WILL REMAIN UP FOR A WHILE IN THE
EVENING...9 PM STILL LOOKS GOOD FOR RED FLAG EXPIRATION BUT THERE
WILL STILL BE SOME WIND AFTER THAT.

LONG TERM...MODELS HAVE AN UPPER RIDGE AXIS MOVE SLOWLY EASTWARD
ACROSS THE FORECAST AREA WEDNESDAY AND WEDNESDAY NIGHT.  THURSDAY
AND THURSDAY NIGHT...THERE IS SOUTHWESTERLY FLOW ALOFT OVER THE CWA.
THE SYNOPTIC SCALE ENERGY IS BENIGN ALL FOUR PERIODS. THE LOW
LEVEL PRESSURE AND WIND FIELDS POINT TO A SURGE OF A BIT COOLER
AIR TO MOVE IN BY WEDNESDAY MORNING. THE LOW LEVEL WINDS ARE
PROGGED TO BE NORTH-NORTHEASTERLY WEDNESDAY MORNING...THEN EAST-
SOUTHEASTERLY BY WEDNESDAY AFTERNOON...CONTINUING WELL INTO
THURSDAY. NORMAL DIURNAL PATTERN WINDS KICK IN THURSDAY NIGHT. FOR
MOISTURE...THERE IS SOME MAINLY IN THE UPPER LEVELS THROUGH THE
FOUR PERIODS...AND EVEN SOME DOWN LOW EARLY THURSDAY MORNING OUT
ON THE PLAINS. DEW POINT PROGGS SHOW 20S TO LOWER 30S F READINGS
OVER THE MOUNTAINS AND FOOTHILLS THROUGH THE PERIOD. OVER THE
PLAINS...THEY RANGE FROM THE LOWER 30S F OVER THE WEST TO THE 50S
F OVER THE EAST WEDNESDAY THROUGH MUCH OF THURSDAY. LATER THURSDAY
AFTERNOON AND EVENING...READINGS CLIMB INTO THE 40S OVER THE
WESTERN PLAINS. THE CAPE IS LIMITED MAINLY TO THE EASTERN AND
NORTHEASTERN BORDER AREAS FOR LATE DAY WEDNESDAY. THE NAM ALSO
SHOWS A TAD OVER THE MOUNTAINS AND FOOTHILLS FOR THAT PERIOD. CAPE
VALUES ARE A BIT HIGHER LATE DAY THURSDAY AND IT COVERS MUCH OF
THE CWA. ALTHOUGH THE ONLY DECENT VALUES...1000-3000 J/KG ARE
CONFINED TO THE EASTERN AND NORTHEASTERN BORDER. THERE IS A
SUBSTANTIAL CAP IN PLACE OVER MUCH OF THE PLAINS WEDNESDAY...LESS
OF ONE ON THURSDAY. THERE IS A TAD OF MEASURABLE RAINFALL OVER
THE SOUTHWESTERN CWA LATE DAY WEDNESDAY ONLY ON THE NAM. BY LATE
DAY THURSDAY...THERE IS WIDER COVERAGE OF A TAD OF MEASURABLE
RAINFALL OVER THE CWA ON ALL THE MODELS. FOR POPS... WILL GO WITH
MINOR ONES LATE DAY WEDNESDAY FOR THE MOUNTAINS AND FOOTHILLS
..THEN 10-20%S FOR MOST OF THE CWA LATE DAY THURSDAY. FOR
TEMPERATURES...WEDNESDAY`S HIGHS ARE 1-4 C COOLER THAN TODAY`S.
THURSDAY`S HIGHS ARE SIMILAR TO WEDNESDAY`S. FOR THE LATER DAYS
..FRIDAY THROUGH MONDAY...MODELS SHOW SOUTHWESTERLY FLOW ALOFT ON
FRIDAY INTO SUNDAY...THEN AN UPPER RIDGE AXIS GETS OVER COLORADO
THROUGH MONDAY. THERE MAY BE ENOUGH MOISTURE AROUND TO WARRANT A
SLIGHT CHANCE OF LATE DAY SHOWERS AND STORMS FOR MOST AREAS MOST
DAYS. TEMPERATURES COOL OFF A BIT FROM CURRENT READINGS...BUT
THEY WILL STILL BE ABOVE SEASONAL NORMALS.

AVIATION...VFR CONDITIONS THROUGH TONIGHT. GUSTY SOUTHWEST WINDS
WILL DEVELOP THIS MORNING...BECOMING WEST TO NORTHWEST THIS
AFTERNOON WITH GUSTS IN THE 30 TO 40 KNOT RANGE. THE WINDS WILL
APPROACH CROSSWIND LIMITS AT KDEN/KAPA IN THE AFTERNOON AND EARLY
EVENING...THEN BECOME MORE NORTHWESTERLY AND DIMINISH THIS
EVENING.

HYDROLOGY...NO ISSUES TODAY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ214>216-246-
247.

&&

$$

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