Hail in Colorado, July 8, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
210 PM MDT SUN JUL 8 2007

.SHORT TERM...WATER VAPOR IMAGERING SHOWING UPPER LVL WAVE ACROSS NW
CO AND SECONDARY WAVE STILL BACK ACROSS NW WY. THIS WILL PROVIDE
SOME MODERATE FORCING FOR STORM DEVELOPMENT AND CONTINUATION THRU
THIS EVENING AND ACROSS FAR NERN CO EVEN PAST MIDNIGHT. 88D SHOWING
STORMS BECOMING EXPANDING ACROSS MTNS AND WILL BEGIN TO MOVE OUT
OVER THE PLAINS DURING THE NEXT FEW HOURS. MID LVL FLOW ALSO
INCREASING AS LOCAL PROFILERS SHOWING ABOUT 25KT AT 500MB. FLOW
SHOULD CONTINUE TO INCREASE THIS EVENING AS 12Z SLC RAOB SHOWED 40KT
AT 500MB. QUESTION WILL BE HOW STRONG STORMS WILL BECOME ON THE
PLAINS. ACROSS THE URBAN CORRIDOR...AIRMASS STILL IS CAPPED WITH
INVERSION AROUND 750MB PER ACARS SOUNDINGS AND WITH TEMPS IN THE MID
80S AND DEWPOINTS STRUGGLING TO STAY IN THE MID 40S...THIS STILL
RESULTS IN QUITE A BIT OF CIN TO OVERCOME. FEEL...STORMS WILL WEAKEN
ACROSS THE URBAN CORRDIOR WITH GUSTY WINDS THE MAIN THREAT THRU THIS
EVENING. FURTHER EAST....LOW LVL MSTR IS A BIT MORE PLENTIFUL WITH
SFC DEWPOINTS IN THE LOWER TO MID 50S AND AFTN TEMPS AROUND 90. THIS
RESULTS IN CAPE VALUES FROM 1500-2000J/KG. STILL EXPECT A FEW SEVERE
STORMS OVER THE FAR PLAINS WITH LARGE HAIL AND GUSTY WINDS THE MAIN
THREATS.

THERE IS A SECONDARY SURGE ACROSS MONTANNA AND THE DAKOTAS WITH SFC
DEWPOINTS IN THE LOWER 60S. THE NAM KIND OF WASHES THE FRONT OUT
OVER NE CO LATER TNT BUT HIGHER DEWPOINTS DUE WORK ITS WAY WESTWARD
THRU THE NIGHT. NAM SHOWING SOME LIGHT QPF OVER MUCH OF ERN CO MON
AM BUT FEEL THIS IS OVERDONE. AIRMASS BECOMES FAIRLY CAPPED MON AFTN
FROM NAM FCST SOUNDINGS WITH GFS SOUNDINGS A BIT WEAKER. WILL LOWER
POPS BUT WONT REMOVE COMPLETELY AS THIS IS STILL GOOD MSTR IN THE
AIR WTIH PW VALUES AROUND AN INCH. EXPECT MOST THE STORM ACTIVITY
MON AFTN WILL BE OVER THE MTNS AND HIGHER TERRAIN.

.LONG TERM...AIRMASS CONTINUES TO STABILIZE MONDAY EVENING SO HAVE
DROPPED POPS A BIT.  EXCEPTION SHOULD BE PARK COUNTY WHERE THIS
PATTERN IS QUITE FAVORABLE FOR SHOWERS/STORMS.  ON TUESDAY...WE
START OFF THE DAY FAIRLY DRY BUT MOISTURE SHOULD RETURN THANKS TO
ANOTHER COLD FRONT AND PLENTY OF LOW LEVEL MOISTURE ADVECTED IN FROM
THE CENTRAL PLAINS LATE IN THE DAY.  QUESTION AGAIN WILL BE WHETHER
OR NOT WE CAN BREAK THE CAP.  TERRAIN SHOULD BE THE BEST FORCING
FEATURE LIKE TODAYS FRONT SO WILL PLAY UP THE HIGHEST POPS IN/NEAR
THE FRONT RANGE.  WOULD NOT BE SURPRISED TO SPARK A FEW SEVERE
STORMS SINCE INSTABILITY WILL BE SUFFICIENT WITH CAPES OF 1000-2000
J/KG BEHIND THE FRONT.  MID LEVEL WINDS CLOSE TO 30 KNOTS WILL ALSO
RESULT IN MARGINAL 0-6 KM SHEAR OF 15-20 M/S.

BY WEDNESDAY...THERE SHOULD BE PLENTY OF LOW LEVEL MOISTURE BACKED
UP AGAINST AND INTO THE FRONT RANGE FOR ANOTHER ROUND OF AFTERNOON/
EVENING THUNDERSTORMS.  SHEAR IS FORECAST TO STRENGTHEN RATHER
CONSIDERABLY BY WEDNESDAY SO IF CAP CAN BE BROKEN THIS COULD BE THE
MOST ACTIVE DAY WITH REGARD TO SEVERE WEATHER THIS WEEK.
HOWEVER...IT SHOULD ALSO BE NOTED THAT TIMING ANY SHORT WAVES AND
INCREASING MID LEVEL WINDS BECOMES INCREASINGLY DIFFICULT THIS FAR
OUT.  THEREFORE...FURTHER REFINEMENTS WILL HAVE TO BE MADE REGARDING
ANY SIGNIFICANT WEATHER POTENTIAL FOR WEDNESDAY THROUGH THE LATTER
HALF OF THE WEEK.

OVERALL...THE ENSEMBLES DO SUGGEST MORE RIDGING AND WARMING NEXT
WEEKEND SO REFLECTED THAT TREND WITH A MODEST WARMUP THEN.
OTHERWISE TEMPERATURES SHOULD ACTUALLY AVERAGE SLIGHTLY BELOW NORMAL
THIS WEEK WITH COOL NORTHWEST FLOW ALOFT AND SEVERAL WEAK FRONTAL
PASSAGES.

&&

.AVIATION...SCT TSRA WILL MOVE ACROSS THE DENVER AREA AIRPORTS BTWN
21-04Z. WIND GUSTS WILL BE THE MAIN THREATS WITH ERRATIC DIRECTIONS
AND SPEEDS UP TO 45KT. VFR CONDITIONS EXPECTED FOR NXT 24 HRS.

&&

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

&&

SWE/DBB

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE DENVER CO
1218 PM MDT SUN JUL 08 2007

COZ030>051-091200-
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-
1218 PM MDT SUN JUL 08 2007

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS THE MOUNTAINS AND
FOOTHILLS BY EARLY THIS AFTERNOON...THEN SPREAD ACROSS THE NORTHEAST
PLAINS OF COLORADO BY LATE AFTERNOON AND CONTINUE THROUGH THE
EVENING HOURS. A FEW STORMS COULD BE SEVERE TODAY WITH HAIL UP TO 2
INCHES IN DIAMETER AND DAMAGING WINDS TO 70 MPH. THE BEST CHANCE FOR
SEVERE STORMS WILL BE JUST EAST OF THE INTERSTATE 25 URBAN CORRIDOR
WHERE THE BEST LOW LEVEL MOISTURE RESIDES. STORMS WILL GRADUALLY
DIMINISH AFTER MIDNIGHT ACROSS THE FAR NORTHEAST PLAINS.

A COLD FRONT WHICH MOVED THROUGH NORTHEAST COLORADO THIS MORNING HAS
ALLOWED LOW LEVEL MOISTURE TO INCREASE ACROSS THE PLAINS...WHILE AN
UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA THIS EVENING.
THESE FACTORS WILL HELP TO ENHANCE THUNDERSTORM ACTIVITY TODAY.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

SOMEWHAT MORE STABLE AIR IS EXPECTED TO SPREAD ACROSS NORTHEAST
COLORADO MONDAY...RESULTING IN LESS STORM COVERAGE.  THE MAIN THREAT
OF STORMS MONDAY AFTERNOON AND EVENING WILL SHIFT INTO THE SOUTHERN
FRONT RANGE FOOTHILLS AND PARK COUNTY...BUT EVEN THERE STORM
COVERAGE MAY BE LIMITED BY THE MORE STABLE AIRMASS.

THUNDERSTORM CHANCES ALONG WITH THE THREAT OF SEVERE WEATHER IS
EXPECTED TO INCREASE AGAIN BY TUESDAY EVENING AND THEN AGAIN
WEDNESDAY.  ANOTHER COLD FRONT WILL BRING COOLER TEMPERATURES...
MORE MOISTURE...AND HIGHER INSTABILITY ACROSS THE FRONT RANGE AND
EASTERN PLAINS OF COLORADO AT THAT TIME.

THE RELATIVELY UNSETTLED AND COOLER WEATHER PATTERN CAN THEN
BE EXPECTED THROUGH THE END OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 3 PM TODAY ACROSS NORTHEAST
COLORADO.

SWE/DBB