Severe Thunderstorm Warning 73, NWS Denver/Boulder, CO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
344 PM MDT MON JUN 17 2013

.SHORT TERM...88D AND AREA RADARS INDICATE SCATTERED THUNDERSTORMS
ALREADY DEVELOPING OVER EAST SLOPES OF THE FRONT RANGE AND
ELEVATED TERRAIN OF PALMER DIVIDE AND NORTH OVER THE CYS RIDGE.
GIVEN THE WEAK SURGE OF INCREASING MOISTURE THIS MORNING...SURFACE
DEWPOINTS HAVE BEEN ABLE TO HOLD UP IN THE 40S AND LOWER 50S OVER
MUCH OF THE AREA. STILL LOOKING AT THE BEST CHANCE FOR SEVERE
STORMS OVER THE PLAINS AND SEVERE THUNDERSTORM WATCH WILL BE
ISSUED SHORTLY FOR MUCH OF NORTHEAST COLORADO. STRONGEST STORMS
STILL EXPECTED ON THE PLAINS WITH BETTER SOUTHEAST LOW LEVEL
INFLOW AND SURFACE BASED CAPES OF 1000-2000J/KG. MAIN THREATS OF
LARGE HAIL UP TO 2 INCH IN DIAMETER AND DAMAGING WINDS.

STORMS WILL END LATER THIS EVENING THE MODELS SHOWING A VARYING
AMOUNTS OF LOW LEVEL MOISTURE RETURNING WEST OF EASTERN COLORADO
TUESDAY WILL BE OUR LAST DAY FOR A WHILE FOR THUNDERSTORMS OVER
EASTERN COLORADO BEFORE DRIER AIR MOVES IN FROM THE WEST. LOOKS
LIKE ANOTHER DAY FOR SEVERE WEATHER ON THE PLAINS WITH DECENT
SOUTHEAST AND MOIST LOW LEVEL FLOW AND CAPES UP TO 2000J/KG.

.LONG TERM...THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA
TUESDAY EVENING... MAINLY ACROSS THE PLAINS WHERE EASTERLY
SURFACE WINDS WILL CONTINUE TO PROVIDE UPSLOPE FLOW. CAPE VALUES
LOWER TO AROUND 1000 J/KG DURING THE EVENING. BUT ENOUGH SHEAR
COULD PRODUCE A FEW SEVERE STORMS...WITH HAIL AND WINDS THE MAIN
CONCERNS. WITH PRECIPITABLE WATER VALUES AROUND EIGHT TENTHS OF AN
INCH ACROSS THE PLAINS... BRIEF HEAVY RAIN COULD ACCOMPANY THE
STORMS. THE STORMS WILL MOVE EAST DURING THE EVENING WITH
GRADUALLY CLEARING SKIES. A FEW STORMS COULD LINGER OVER THE FAR
EASTERN PLAINS AFTER MIDNIGHT. FOR WEDNESDAY...UPPER LEVEL RIDGE
AXIS SHIFTS EAST INTO THE CENTRAL PLAINS AS UPPER TROUGH MOVES
INTO THE NORTHERN GREAT BASIN. FLOW ALOFT ACROSS COLORADO BECOMES
SOUTHWEST...BRINGING DRIER AND WARMER AIR INTO THE REGION. MODELS
SHOW LOW LEVEL CONVERGENCE ACROSS FAR EASTERN PLAINS WHERE A FEW
STORMS COULD DEVELOP DURING THE AFTERNOON. STORMS TO PRODUCE GUSTY
WINDS AND BRIEF MODERATE RAINFALL. ELSEWHERE NO STORMS EXPECTED.
DAYTIME HEATING TO PRODUCE ENOUGH MIXING TO ALLOW SOME GUSTY WINDS
TO MIX TO THE SURFACE. MODELS INDICATE THE HIGHER WINDS ACROSS
SOUTH PARK AND THE PALMER DIVIDE DURING THE AFTERNOON. HUMIDITY
READINGS EXPECTED TO DROP INTO THE TEENS WHICH WILL ELEVATE THE
FIRE DANGER. WILL HOLD OFF ON ANY FIRE WEATHER WATCH AT THIS TIME
AS THERE IS SOME POTENTIAL FOR WETTING RAINS TODAY AND TUESDAY
WHICH COULD EASE THE FIRE DANGER. ON THURSDAY...THE SOUTHWEST FLOW
ALOFT INCREASES WHICH WILL INCREASE SURFACE WINDS ACROSS MUCH OF
THE AREA. AIRMASS WILL BE WARMER AND DRIER...WHICH WILL KEEP THE
FIRE DANGER ELEVATED WITH POTENTIAL FOR CRITICAL FIRE WEATHER
CONDITIONS. MAIN AREAS OF CONCERN WILL BE THE FRONT RANGE
FOOTHILLS...PALMER DIVIDE AND SOUTH PARK.

FOR THE LATER DAYS SATURDAY THROUGH MONDAY....MODERATE SOUTHWEST
FLOW TO CONTINUE...THOUGH A BIT WEAKER. MODELS SHOW UPPER TROUGH
TRACKING ACROSS IDAHO AND MONTANA DURING THE WEEKEND. SURFACE
FRONT PROGGED TO MOVE INTO NORTHEAST PLAINS SATURDAY MORNING WITH
SOME COOLING AND AN INCREASE IN LOW LEVEL MOISTURE. COULD SEE A
RETURN OF AFTERNOON THUNDERSTORMS FOR THE WEEKEND. AIRMASS LOOKING
A BIT DRY FOR MONDAY AS MOISTURE APPEARS TO BE FLUSHED EASTWARD.
WILL KEEP MONDAY VOID OF STORMS FOR NOW.

&&

.AVIATION...SCATTERED THUNDERSTORMS OVER THE FRONT RANGE SHOULD
EFFECT TERMINALS BETWEEN 21-23Z AND ALREADY HAVE TEMPO FOR TSRA IN
THE TAFS. UNSURE HOW MUCH STRATUS AND FOG WILL MAKE IT BACK IN
LATER TONIGHT AND FOR NOW JUST INDICATED SCATTERED LOWER DECK OF
CLOUDS.

&&

.HYDROLOGY...SOME STRONG STORMS OVER THE FRONT RANGE FOOTHILLS BUT
STORMS ARE MOVING AT A DECENT CLIP AND EXPECT MOST STORMS TO
PRODUCE A QUARTER INCH IN 30 MINUTES WITH THE STRONGER STORMS OVER
THE FOOTHILLS.

&&

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

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1057 AM MDT MON JUN 17 2013

COZ030>051-181700-
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-
1057 AM MDT MON JUN 17 2013

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

.DAY ONE...TODAY AND TONIGHT

ISOLATED THUNDERSTORMS ARE ALREADY DEVELOPING OVER THE SOUTHERN
PORTIONS OF THE FRONT RANGE AS WEAK DISTURBANCE PASSES OVER THE
AREA. MOISTURE LEVELS HAVE ALSO INCREASED SLIGHTLY AS WEAK SURGE
OF NORTHEAST WINDS HAVE DEVELOPED OVER THE PLAINS. STORMS WILL
BECOME MORE NUMEROUS DURING THE AFTERNOON. MOISTURE WILL BE MORE
LIMITED IN THE MOUNTAINS AND FRONT RANGE URBAN CORRIDOR SO THE
MAIN THREAT FROM THESE STORMS WILL BE CLOUD TO GROUND LIGHTNING
AND STRONG GUSTY WINDS TO AROUND 50 MPH. THERE WILL BE BETTER LOW
LEVEL MOISTURE AND INSTABILITY OVER THE EASTERN PLAINS...SO A FEW
SEVERE STORMS WILL BE POSSIBLE WITH GOLF BALL SIZE HAIL AND
DAMAGING WINDS. THE BEST CHANCE FOR SEVERE STORMS WILL BE EAST OF
A LINE FROM CHEYENNE TO FORT MORGAN TO LIMON.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
AFTERNOON AND EVENING ON TUESDAY. SOME OF THE STORMS COULD AGAIN
BE SEVERE EAST OF THE URBAN CORRIDOR. A DRY AND WARMER
SOUTHWESTERLY FLOW ALOFT WILL RETURN TO THE REGION WEDNESDAY
THROUGH SUNDAY WITH ONLY A SLIGHT CHANCE OF LATE DAY
THUNDERSTORMS. THE FIRE DANGER WILL BE INCREASING...ESPECIALLY ON
THURSDAY AND FRIDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED OVER THE NORTHEAST PLAINS AFTER 2 PM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
1143 AM MDT MON JUN 17 2013

COZ041-171815-
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
1143 AM MDT MON JUN 17 2013

THE NATIONAL WEATHER SERVICE HAS ISSUED A SIGNIFICANT WEATHER
ADVISORY FOR SOUTHEASTERN DOUGLAS AND WEST CENTRAL ELBERT COUNTIES
UNTIL 1215 PM MDT.

AT 1143 AM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM 8 MILES WEST OF ELBERT...OR 36 MILES SOUTHEAST
OF DENVER...MOVING EAST AT 15 MPH.

HAIL UP TO THE SIZE OF DIMES AND WIND GUSTS UP TO 40 MPH WILL BE
POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE BUT ARE NOT LIMITED TO...
ELBERT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

&&

LAT...LON 3914 10481 3933 10478 3934 10443 3914 10447
TIME...MOT...LOC 1743Z 264DEG 13KT 3924 10470

RPK

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
154 PM MDT MON JUN 17 2013

COZ034-035-039-172030-
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-BOULDER AND JEFFERSON COUNTIES BELOW 6000 FEET/WEST BROOMFIELD
COUNTY-
154 PM MDT MON JUN 17 2013

THE NATIONAL WEATHER SERVICE HAS ISSUED A SIGNIFICANT WEATHER
ADVISORY FOR CENTRAL BOULDER COUNTY UNTIL 230 PM MDT.

AT 154 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM OVER WALLSTREET...OR 32 MILES NORTHWEST OF
DENVER...MOVING SOUTH AT 20 MPH.

HAIL UP TO THE SIZE OF DIMES AND WIND GUSTS UP TO 40 MPH WILL BE
POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE BUT ARE NOT LIMITED TO...
BOULDER...NEDERLAND...JAMESTOWN...WARD...SALINA...CRISMAN...GOLD
HILL...SUMMERVILLE...PEACEFUL VALLEY...WALLSTREET...RAYMOND...
SUNSHINE...ALLENSPARK AND ELDORADO SPRINGS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

&&

LAT...LON 3994 10552 4019 10554 4019 10525 3995 10521
TIME...MOT...LOC 1954Z 353DEG 19KT 4004 10542

RPK

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
200 PM MDT MON JUN 17 2013

COZ049-172030-
WASHINGTON COUNTY-
200 PM MDT MON JUN 17 2013

THE NATIONAL WEATHER SERVICE HAS ISSUED A SIGNIFICANT WEATHER
ADVISORY FOR SOUTHERN WASHINGTON COUNTY UNTIL 230 PM MDT.

AT 200 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 4 MILES NORTHWEST OF THURMAN...OR 32 MILES
NORTHEAST OF LIMON...MOVING EAST AT 10 MPH.

HAIL UP TO THE SIZE OF NICKELS AND WIND GUSTS UP TO 40 MPH WILL BE
POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE BUT ARE NOT LIMITED TO...
THURMAN...LINDON AND ANTON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

&&

LAT...LON 3977 10303 3957 10306 3957 10350 3977 10349
TIME...MOT...LOC 2000Z 270DEG 11KT 3963 10330

RPK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
415 PM MDT MON JUN 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0303 PM     HAIL             4 N ARICKAREE SCHOOL    39.80N 103.03W
06/17/2013  M1.25 INCH       WASHINGTON         CO   TRAINED SPOTTER

            TIME ESTIMATED

&&

KFREDIN