Severe Thunderstorm Warning 77, NWS Denver/Boulder, CO

000 
WWUS55 KBOU 260023
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
623 PM MDT WED JUN 25 2008

COC121-260033-
/O.CAN.KBOU.SV.W.0077.000000T0000Z-080626T0045Z/
WASHINGTON CO-
623 PM MDT WED JUN 25 2008

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL WASHINGTON COUNTY IS
CANCELLED...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO
LONGER EXPECTED TO PRODUCE SEVERE WEATHER.

LAT...LON 4005 10292 3978 10296 3983 10335 4002 10330
TIME...MOT...LOC 0023Z 286DEG 14KT 3985 10309

$$
BARJENBRUCH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
300 PM MDT WED JUN 25 2008

.SHORT TERM...ONCE AGAIN THIS AFTERNOON ISOLATED THUNDERSTORMS ARE
BREWING OVER THE HIGHER TERRAIN...THEN COLLAPSING AND CREATING HUGE
OUTFLOW WINDS IN OUR DEWPOINT DEPRIVED LOWER ELEVATIONS.  LOOKING AT
SATELLITE THUNDERSTORMS ARE MORE IMPRESSIVE ACROSS WYOMING...AND
THIS WHOLE BAND OF STORMS WITH WESTERLY OUTFLOW WILL EVENTUALLY
REACH THE EASTERLY WINDS AND HIGHER DEWPOINTS IN EASTERN WYOMING...
THE NEBRASKA PANHANDLE AND NORTHEAST COLORADO.  A FEW SEVERE
THUNDERSTORMS LOOK POSSIBLE THIS EVENING IN THE NORTHEAST...
ESPECIALLY LOGAN...SEDGWICK AND PHILLIPS COUNTIES WHERE DEWPOINTS
ARE EXPECTED TO REMAIN IN THE 50S.  ALSO MODELS INDICATE INCREASING
EAST WINDS THIS EVENING SO MOISTURE ADVECTION WILL BE MAINTAINED.

WITH A THERMAL RIDGE ALOFT AND DOWN VALLEY WINDS DEVELOPING
TONIGHT...MINS WILL REMAIN HIGH AND GUIDANCE VALUES LOOK GOOD.

THURSDAY...THE THERMAL RIDGE GETS EVEN MORE AMPLIFIED AND YOU CAN
ADD A FEW DEGREES TO MAX TEMPS.  MID TO UPPER 90S LOOK REASONABLE
FOR THURSDAY MAX TEMPS...BUT PRESENCE OF CONVECTIVE DEBRIS CLOUDS
MAY LOWER TEMPS A DEGREE OR TWO.  PREVIOUS FORECAST KEPT 0 POPS IN
SOUTH PLATTE BASIN...WITH ISOLATE CONVECTION OVER MOUNTAINS AND
FOOTHILLS...AND NORTHEAST CORNER...AND THIS LOOKS REASONABLE GIVEN
THE EXPECTED THERMAL RIDGE...BUT COLLAPSING STORMS MOVING FROM THE
HIGHER TERRAIN MAY AGAIN CAUSE GUSTY OUTFLOW WINDS.

.LONG TERM...MODELS KEEP SHOWING THE UPPER RIDGE TO FLATTEN THURSDAY
NIGHT AND FRIDAY WITH AN UPPER TROUGH SLIDING EASTWARD WELL TO OUR
NORTH.  THE FLOW ALOFT REMAINS WEAK AND WESTERLY THURSDAY NIGHT AND
FRIDAY.  BY FRIDAY NIGHT...THE UPPER RIDGE AXIS BUILDS NORTHWESTWARD
AND IS TO OUR WEST.  THE FLOW ALOFT FOR THE FORECAST AREA IS
NORTHWESTERLY WELL INTO THE EXTENDED PERIOD.  THE QG VERTICAL
VELOCITY FIELDS SHOW BENIGN VERTICAL MOTION THROUGH THE PERIODS.  A
COOLER SURGE OF AIR IS EXPECTED INTO THE PLAINS OVERNIGHT THURSDAY
WITH THE BOUNDARY LAYER FLOW BECOMING UPSLOPE BY 12Z FRIDAY MORNING
AND CONTINUING INTO SATURDAY EVENING.  FOR MOISTURE...BOTH MODELS
SHOW SOME IN THE LOWER LEVELS OF THE PLAINS BY FRIDAY MORNING.  ON
FRIDAY ...THERE IS SOME MOISTURE FOR THE FORECAST AREA...MAINLY IN
THE MID LEVELS.  THE LOWER LEVELS OF THE PLAINS ARE OK TOO.  THE
EASTERN TWO-THIRDS OF THE FORECAST AREA HAVE DECENT MOISTURE FRIDAY
NIGHT THROUGH SATURDAY NIGHT.  PRECIPITABLE WATER VALUES ARE 0.70 TO
1.00 INCH FRIDAY THROUGH SATURDAY NIGHT OVER THE PLAINS AND LOWER
FOOTHILLS.  BOUNDARY LAYER DEW POINTS GET INTO THE 50S F OVER THE
PLAINS BY FRIDAY MORNING...AND DECREASE INTO THE 40S F BY
AFTERNOON.  THEY STAY IN THE 40S F THROUGH MID DAY SATURDAY...THEN
GET BACK INTO THE 50S F BY AFTERNOON.  THE LAPSE RATES ARE PRETTY
STEEP THURSDAY EVENING.  ON FRIDAY...THERE IS A MID LEVEL CAP OVER
MOST OF THE PLAINS THROUGH MID AFTERNOON.  AROUND 00Z THE LAPSE
RATES ARE FAIRLY STEEP OVER THE PLAINS.  ON SATURDAY THE CAP IS
STRONGER THAN ON FRIDAY...ESPECIALLY OVER THE EASTERN TWO-THIRDS OF
THE PLAINS.  THERE IS SOME CAPE OVER THE NORTHEAST CORNER THURSDAY
EVENING.  ON FRIDAY THERE IS SOME CAPE IN THE MOUNTAINS AND
FOOTHILLS...THE PLAINS DO NOT HAVE MUCH.  CAPE ON SATURDAY IS
CONFINED TO THE MOUNTAINS...FOOTHILLS...AND IMMEDIATE PLAINS.  THE
QPF FIELDS SHOW VERY LITTLE MEASURABLE RAINFALL OVER THE FORECAST
AREA THROUGH THE PERIOD.  FOR POPS...AGAIN WILL KEEP 0-20%S THROUGH
SATURDAY EVENING.  FOR TEMPERATURES...FRIDAYS HIGHS COOL DOWN 5-8 C
FROM THURSDAYS HIGHS.  SATURDAYS HIGHS ARE SIMILAR TO FRIDAYS.
FOR THE LATER DAYS...SUNDAY THROUGH WEDNESDAY...MODELS KEEP THE
UPPER RIDGE AXIS RIGHT OVER COLORADO THROUGH MUCH OF THE TIME.
THERE MAY BE SOME MOISTURE TRAPPED IN THE RIDGE.  WILL STILL LEAN
TOWARDS DRY WITH MINIMAL POPS AND TEMPERATURES SLIGHTLY ABOVE
SEASONAL NORMALS.

&&

.AVIATION...ISOLATED HIGH BASED THUNDERSTORMS FROM THE MOUNTAINS ARE
STILL POSSIBLE THROUGH 6PM AT DIA...WITH LITTLE RAIN...BUT STRONG
OUTFLOW WINDS GUSTING TO 40 KNOTS.  DOWNSLOPE FLOW DEVELOPS LATER
EVENING AND OVERNIGHT WITH VFR CONDITIONS.  THURSDAY WILL BE HOT AND
MOSTLY DRY...BUT GUSTY OUTFLOW WINDS WILL AGAIN BE POSSIBLE BETWEEN
18Z AND 00Z.

&&

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

&&

GLANCY/RJK

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1039 AM MDT WED JUN 25 2008

COZ030>051-261200-
JACKSON COUNTY BELOW 9000 FEET-WEST JACKSON AND WEST GRAND
COUNTIES ABOVE 9000 FEET-GRAND AND SUMMIT COUNTIES BELOW 9000
FEET-SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/
NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-SOUTH AND SOUTHEAST
GRAND/WEST CENTRAL AND SOUTHWEST BOULDER/GILPIN/CLEAR CREEK/
SUMMIT/NORTH AND WEST PARK COUNTIES ABOVE 9000 FEET-LARIMER AND
BOULDER COUNTIES BETWEEN 6000 AND 9000 FEET-JEFFERSON AND WEST
DOUGLAS COUNTIES ABOVE 6000 FEET/GILPIN/CLEAR CREEK/NORTHEAST PARK
COUNTIES BELOW 9000 FEET-CENTRAL AND SOUTHEAST PARK COUNTY-LARIMER
COUNTY BELOW 6000 FEET/NORTHWEST WELD COUNTY-BOULDER AND JEFFERSON
COUNTIES BELOW 6000 FEET/WEST BROOMFIELD COUNTY-NORTH DOUGLAS
COUNTY BELOW 6000 FEET/DENVER/WEST ADAMS AND ARAPAHOE COUNTIES/
EAST BROOMFIELD COUNTY-ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES
ABOVE 6000 FEET-NORTHEAST WELD COUNTY-CENTRAL AND SOUTH WELD
COUNTY-MORGAN COUNTY-CENTRAL AND EAST ADAMS AND ARAPAHOE COUNTIES-
NORTH AND NORTHEAST ELBERT COUNTY BELOW 6000 FEET/NORTH LINCOLN
COUNTY-SOUTHEAST ELBERT COUNTY BELOW 6000 FEET/SOUTH LINCOLN
COUNTY-LOGAN COUNTY-WASHINGTON COUNTY-SEDGWICK COUNTY-PHILLIPS
COUNTY-
1039 AM MDT WED JUN 25 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

.DAY ONE...TODAY AND TONIGHT

ISOLATED THUNDERSTORMS WILL AGAIN DEVELOP OVER THE MOUNTAINS AND
FOOTHILLS EARLY THIS AFTERNOON. THE STORMS WILL SPREAD EAST OVER THE
PLAINS DURING THE AFTERNOON AND EVENING. DUE TO THE DRY AIRMASS THE
THUNDERSTORMS WILL BE HIGH BASED AND WILL PRODUCE GUSTY OUTFLOW
WINDS WITH GUSTS UP TO 50 MPH.  THE EXCEPTION WILL BE IN EXTREME
NORTHEAST COLORADO WHERE DEWPOINTS ARE HIGHER AND THERE IS A SLIGHT
CHANCE OF SEVERE THUNDERSTORMS THIS EVENING OVER LOGAN...PHILLIPS
AND SEDGWICK COUNTIES.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE WILL BE A SLIGHT CHANCE OF LATE DAY SHOWERS AND THUNDERSTORMS
FOR MUCH OF THE FORECAST AREA THROUGH THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.

GLANCY/RJK