National Weather Service Forecast Discussion

000
FXUS65 KBOU 182154
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
354 PM MDT TUE JUN 18 2013

.SHORT TERM...FELT LIKE IT WAS BACK IN THE 1980S AS THE DENVER
CYCLONE DID ITS THING WITH A TORNADO FORMING RIGHT OVER THE
AIRPORT. VERY INTERESTING TOTAL LIGHTNING DATA SHOWED RAMP UP
PRIOR TO FIRST INDICATIONS OF CIRCULATION FORMING DOWN LOW. CLOSE
PROXIMITY TO THE RADAR ALLOWED FOR SOME LEAD TIME WITH A NICE
HOOK STRUCTURE ESPECIALLY ON THE TERMINAL DOPPLER RADAR. THINGS
ARE REALLY DRYING OUT BEHIND THE MAIN COMPLEX OF STORMS WHICH IS
NOW EAST OF DIA. SEVERE THREAT WILL CONTINUE INTO THE EVENING AS
THIS AREA OF STORMS HEADS INTO SLIGHTLY BETTER MOISTURE WITH DEW
POINTS INTO THE LOWER 50S. DECENT SHEAR SO CANNOT RULE OUT
SUPERCELLS BUT AN MCS COMPLEX MAY BE MORE LIKELY LATER IN THE
EVENING EAST OF LIMON. CANNOT RULE OUT ANOTHER THUNDERSTORM BACK
ALONG THE FRONT RANGE BUT THINGS REALLY DRYING OUT IN THE HIGHER
TERRAIN AND EXPECT ONLY ISOLATED COVERAGE AND NOT SEVERE AT THIS
POINT.

WARMER DAY TOMORROW AND MOSTLY DRIER WITH MORE OF A DRY LINE
SETTING UP WELL EAST OF DENVER. KEPT ISOLATED THUNDERSTORMS IN THE
AFTERNOON FOR FARTHER EAST WHERE MOISTURE WILL BE MAINTAINED.
LOWERED TEMPERATURES SOME THERE WITH LESS DRYING THEN EARLIER
THOUGHT. RIGHT NOW IT DOES NOT LOOK LIKE THE WINDS WILL BE HIGH
ENOUGH OR MOISTURE LOW ENOUGH FOR FIRE WEATHER THREAT TOMORROW BUT
INSTEAD SOUTHERN PORTION MORE ON THURSDAY.

.LONG TERM...A FEW STORMS WILL BE POSSIBLE ACROSS THE FAR
NORTHEAST CORNER WEDNESDAY EVENING IN AREA OF WEAK CONVERGENCE AND
LINGERING LOW LEVEL MOISTURE. GUSTY WINDS WITH BRIEF MODERATE RAIN
WILL BE POSSIBLE WITH THE STORMS. OTHERWISE...DRY AIR WILL
CONTINUE TO SPREAD ACROSS THE AREA FROM WEST TO EAST...WITH
CLEARING SKIES BY MIDNIGHT. GUSTY SOUTHERLY WINDS OVER THE FAR
EASTERN PLAINS WILL DECREASE DURING THE EVENING WITH A WEAKENING
SURFACE GRADIENT. ON THURSDAY...SOUTHWEST FLOW ALOFT WILL BE OVER
THE AREA AS AN UPPER TROUGH MOVES INTO THE NORTHERN GREAT BASIN.
THIS WILL SPREAD WARMER AND DRIER AIR INTO COLORADO. MODELS
CONTINUE TO SHOW WEAK FRONT MOVING ACROSS THE PLAINS DURING THE
MORNING HOURS WITH SLIGHTLY COOLER AIR AND A SLIGHT INCREASE IN
LOW LEVEL MOISTURE. BY AFTERNOON...IT LOOKS LIKE THERE WILL BE
ENOUGH MIXING ALONG THE PALMER DIVIDE TO CREATE SOUTHERLY WINDS
AND HELP FLUSH OUT THE MOISTURE. THIS COULD CREATE CRITICAL FIRE
WEATHER CONDITIONS ALONG THE PALMER DIVIDE. OTHER AREA OF CONCERN
LOOKS TO BE ACROSS SOUTH PARK. WILL BE HOISTING A FIRE WEATHER
WATCH FOR SOUTH PARK AND THE PALMER DIVIDE THURSDAY AFTERNOON AND
EARLY EVENING FOR GUSTY WINDS AND LOW HUMIDITY. HELD OFF ON
INCLUDING THE SOUTHERN FOOTHILLS... ZONE 36...AS THE CRITICAL
CONDITIONS APPEAR LIMITED TO THE EXTREME SOUTHERN PORTION OF THE
ZONE. WINDS TO DECREASE DURING THE EVENING WITH A SLIGHT INCREASE
IN HUMIDITY...ALLOWING FOR AN IMPROVEMENT IN FIRE WEATHER
CONDITIONS. FOR FRIDAY...MODELS CONTINUE A DRY SOUTHWEST FLOW
ALOFT OVER THE REGION WITH UPPER TROUGH REMAINING OVER THE
NORTHERN GREAT BASIN. THERE APPEARS TO BE A SLIGHT DECREASE IN
WINDS ALOFT. ENOUGH MIXING SHOULD CREATE SOME GUSTY WINDS ACROSS
THE AREA WHICH WILL HELP KEEP THE FIRE DANGER ELEVATED. ON
SATURDAY...FLOW ALOFT BECOMES A BIT MORE WESTERLY AS UPPER TROUGH
MOVES EAST ACROSS IDAHO AND MONTANA. MODELS PUSH A WEAK FRONT INTO
NORTHEAST COLORADO PLAINS WITH SOME INCREASE IN LOW LEVEL
MOISTURE. MAY BE ENOUGH TO GENERATE A FEW THUNDERSTORMS DURING THE
AFTERNOON AND EVENING. APPEARS BEST LOCATION FOR ANY CONVECTION
TO BE FAR EASTERN PLAINS...WILL INCLUDE A SLIGHT CHANCE THERE.
AIRMASS TO BE SLIGHTLY COOLER FROM THE FOOTHILLS EASTWARD. ON
SUNDAY...WESTERLY FLOW ALOFT TO PREVAIL. AIRMASS COOL BUT MOISTURE
LOOKING LIMITED. STILL SOME MOISTURE FAR EASTERN PLAINS WITH WEAK
CONVERGENCE. WILL ADD A FEW STORMS THERE. OTHERWISE DRY CONDITIONS
TO PREVAIL WITH COOL AIRMASS CONTINUING. FOR MONDAY AND
TUESDAY...RIDGE BUILDS OVER AREA WITH WARMER AND DRY CONDITIONS.


&&

.AVIATION...TORNADO MOVED RIGHT OVER DIA ASOS WITH 97 MPH GUST.
STORM DEVELOPED ALONG DCVZ AFTER APPARENT INTERSECTION WITH
OUTFLOW FROM THE SOUTHWEST. SEVERE THREAT HAS NOW SHIFTED TO THE
EAST. SOME WEAK CELLS TRYING TO FORM OVER THE FOOTHILLS BUT LOTS
OF DRYING EVIDENT IN THE OBS SO LOW CHANCE UNLESS OUTFLOW COMES
BACK WESTWARD LATER. WINDS SHOULD GO DRAINAGE LATE THEN MORE
SOUTHWESTERLY FLOW TOMORROW AND ANY THUNDERSTORM THREAT SHOULD BE
EAST.


&&

.HYDROLOGY...COULD BE SOME HEAVIER RAINS AS THE CELLS FORM A
COMPLEX EAST OF LIMON WITH SOME HIGHER DEWPOINTS IN THE
OBS...PARTICULARLY SOUTH OF I-76.


&&

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

&&

$$

SHORT TERM...SZOKE
LONG TERM....D-L
AVIATION...SZOKE

NWS BOU Office Area Forecast Discussion