Severe Thunderstorm Warning 157, NWS Denver/Boulder, CO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
309 PM MDT FRI AUG 7 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 309 PM MDT FRI AUG 7 2015

QG LIFT ASSOCIATED WITH UPPER TROUGH TO OUR WEST WILL GRADUALLY
TRANSITION TO SUBSIDENCE OVERNIGHT/EARLY SATURDAY WITH NEARLY
NEUTRAL VALUES FOR SATURDAY. CONSIDERABLE MIDDLE AND HIGH LEVEL
CLOUDINESS HAS RETARDED MOST CONVECTIVE DEVELOPMENT THUS FAR BUT A
FEW STORMS HAVE POPPED UP ALONG A CONVERGENCE/DRY LINE RUNNING
NORTHEAST FROM NORTH CENTRAL DOUGLAS COUNTY. DEW POINTS ARE
SUBSTANTIAL OVER THE PLAINS...AS IS THE VERTICAL WIND SHEAR...SO
IF THINGS DO GET GOING OUT THERE THE THREAT OF SEVERE WEATHER
ALONG WITH HEAVY RAINS WILL CONTINUE INTO THE EVENING. WITH DEW
POINTS LOWER IN MOST AREAS CLOSER TO THE MOUNTAINS ACTIVITY THERE
SHOULD BE LESS INTENSE.

PRECIPITABLE WATER VALUES CLIMB/REMAIN HIGH OVER ALL OF THE PLAINS
ON SATURDAY SO ANOTHER ROUND OF CONVECTION IS EXPECTED ALONG WITH
SLIGHTLY COOLER TEMPERATURES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 309 PM MDT FRI AUG 7 2015

A WEAK SHORTWAVE MOVES THROUGH THE MOISTURE PLUME BRINGING A GOOD
THREAT OF SHOWERS TO SOUTHEASTERN COLORADO SATURDAY EVENING...BUT
THIS SHOULD JUST BE CLIPPING ACROSS EAST CENTRAL COLORADO AND ONLY
BRING CLOUDS TO ADJACENT AREAS. PATTERN ON SUNDAY LOOKS SIMILAR TO
SATURDAY. THERE MAY BE A BIT MORE DRYING BUT ACCOMPANIED BY A
LITTLE COOLING ALOFT AS WELL...SO STILL LOW POPS MAINLY
MOUNTAINS/SOUTH. SOME MODEL RUNS NOW HAVE A STRONGER LOW LEVEL
SURGE SUNDAY AFTERNOON OR EVENING THAT COULD INCREASE LOW/MID
LEVEL MOISTURE. NOT SURE WHICH WAY THIS WILL IMPACT CONVECTIVE
CHANCES...LIKELY STABILIZING INITIALLY BUT COULD PROVIDE MORE LOW
LEVEL MOISTURE TO WORK WITH ON MONDAY IF THE COOLING AND POSSIBLE
EARLY CLOUD COVER CAN BE OVERCOME. USUALLY THIS IS NOT THE CASE
THOUGH. FOR NOW WENT WITH A BIT MORE CLOUD COVER AND SLIGHTLY
COOLER HIGHS MONDAY ALONG WITH A BIT HIGHER POPS ON THE EDGE OF
THE MOISTURE OVER THE FRONT RANGE.

BEHIND THE SUNDAY NIGHT WAVE...THE RIDGE WILL BUILD STRONGLY
NORTHWARD OVER THE ROCKIES. ECMWF HAS COME IN LINE WITH THE
STRONGER RIDGE THE GFS HAS HAD...AND IS EVEN STRONGER BY
WEDNESDAY. THERE IS STILL A FAIR AMOUNT OF LOW LEVEL MOISTURE
AROUND...WHILE AT HIGHER LEVELS IT NEVER REALLY DRIES OUT BUT
THERE IS NOT MUCH OF A RICH DEEP MOISTURE SOURCE AROUND
EITHER...JUST A MODEST GRADIENT TOWARD BETTER MOISTURE TO THE
SOUTH. THIS RIDGE POSITION INITIALLY WILL TEND TO KEEP THE
BETTER MOISTURE SOUTH OF US...THOUGH THERE IS USUALLY A GRADUAL
NORTHWARD DIFFUSION OVER SEVERAL DAYS. IF THE HIGH GETS EVEN
FURTHER NORTH THEN THERE WOULD BE MORE OF THIS. FOR NOW MODEL
CONSENSUS OF LOW POPS MAINLY OVER THE MOUNTAINS AND HIGHS IN THE
UPPER 80S/LOW 90S IS FINE. AGAIN...A COUPLE DAYS COULD BE WARMER
IF THE RIDGE IS STRONG AND THERE IS LITTLE CLOUD COVER.

&&

.AVIATION...(FOR THE TAFS THROUGH 00Z SATURDAY LATE AFTERNOON)
ISSUED AT 309 PM MDT FRI AUG 7 2015

SOME THREAT OF CONVECTION AT THE AIRPORTS THIS AFTERNOON AND EARLY
EVENING. WITH LOW DEW POINTS GUSTY WINDS WILL BE THE MAIN THREAT
WITH STORMS THAT DEVELOP. DENVER CYCLONE IS FLOATING AROUND TO THE
EAST OF THE URBAN CORRIDOR KEEPING LIGHT NORTH TO WEST WINDS AT
THE TERMINALS AT THIS HOUR BUT HIGH RESOLUTION MODELS WANT TO SLIP
IT WESTWARD LATER...BRINGING GUSTY SOUTHEASTERLIES BACK INTO THE
AREA. WITH CONVECTION AROUND IT WILL BE A TOUGH CALL TO PIN DOWN
ANY CONSISTENT DIRECTION. STILL ANTICIPATING SOME DRAINAGE FLOW
OVERNIGHT ALTHOUGH PERHAPS A BIT MORE WESTERLY COMPONENT. EXPECT
ANOTHER ROUND OF CONVECTION SATURDAY AFTERNOON ALONG WITH
SOUTHEASTERLY SURFACE WINDS.

&&

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

&&

SHORT TERM...ET
LONG TERM...GIMMESTAD
AVIATION...ET

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1103 AM MDT FRI AUG 7 2015

COZ030>051-081715-
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-
1103 AM MDT FRI AUG 7 2015

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

.DAY ONE...TODAY AND TONIGHT

THE OUTLOOK AREA TODAY WILL SEE MORE SHOWER AND THUNDERSTORM
ACTIVITY THAN HAS BEEN THE CASE THE LAST COUPLE OF DAYS AS AN
UPPER LEVEL DISTURBANCE CROSSES OVER THE STATE. ENOUGH SHEAR AND
INSTABILITY EXIST OVER THE NORTHEAST COLORADO PLAINS TO KEEP A
THREAT OF SEVERE THUNDERSTORMS OVER THOSE LOCALES LATER THIS
AFTERNOON AND EXTENDING INTO THE EVENING. HEAVY RAINS ARE ALSO
POSSIBLE IN THESE AREAS EAST OF THE URBAN CORRIDOR.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

TEMPERATURES WILL REMAIN WARM AS AN UPPER LEVEL RIDGE WILL BUILD
NORTHWARD FROM THE SOUTHERN PLAINS OVER THE ROCKIES. THERE WILL
STILL BE ENOUGH MOISTURE FOR SCATTERED THUNDERSTORMS THIS
WEEKEND. IT WILL BE A LITTLE WARMER AND DRIER BY THE MIDDLE OF
THE WEEK THOUGH THERE WILL STILL BE A LOW LEVEL OF THUNDERSTORM
ACTIVITY AND THE STORMS THAT DO DEVELOP COULD BE SLOW MOVING WITH
LOCALIZED HEAVY RAINFALL.

.SPOTTER INFORMATION STATEMENT...

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

ET/GIMMESTAD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
331 PM MDT FRI AUG 07 2015

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

0330 PM     HAIL             JACKSON RESERVOIR       40.38N 104.07W
08/07/2015  M1.00 INCH       MORGAN             CO   PARK/FOREST SRVC

&&

SENTREKI

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
346 PM MDT FRI AUG 07 2015

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

&&

SENTREKI

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DENVER CO
354 PM MDT FRI AUG 07 2015

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

0353 PM     HAIL             1 WNW WELDONA           40.35N 103.98W
08/07/2015  M1.00 INCH       MORGAN             CO   TRAINED SPOTTER

0330 PM     HAIL             JACKSON RESERVOIR       40.38N 104.07W
08/07/2015  M1.00 INCH       MORGAN             CO   PARK/FOREST SRVC

0315 PM     HAIL             JACKSON RESERVOIR       40.38N 104.07W
08/07/2015  M1.75 INCH       MORGAN             CO   911 CALL CENTER

&&

SENTREKI