Severe Thunderstorm Warning 131, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
240 PM MDT THU JUL 11 2003

SHORT TERM DISCUSSION:  WEAK FRONT STALLED OUT FROM ROUGHLY CHEYENNE
TO LIMON THIS MORNING.  MOISTURE CONTINUES TO TRICKLE IN DRIVEN
MAINLY BY DIURNAL WINDS.  ON THE WEST EDGE OF THE MOISTURE GRADIENT
IT HAS WARMED ENOUGH FOR WIDESPREAD HIGH BASED CONVECTION.
MEANWHILE IN THE BETTER MOISTURE IT IS STILL TOO COOL.  PROBLEM WITH
THE FORECAST TONIGHT IS WHETHER THE MOIST AIR WILL WARM ENOUGH FOR
STRONG THUNDERSTORMS TO DEVELOP.  ETA AND ACARS SOUNDINGS AND
FOOTHILLS TEMPERATURES SUGGEST THAT MID TO UPPER 90S ARE NEEDED AT
AKRON FOR SURFACE BASED CONVECTION.  THIS DOES NOT APPEAR
LIKELY...PARTICULARLY WITH CLOUDS SPREADING OFF THE MOUNTAINS.
MAYBE A BETTER CHANCE AROUND LIMON WHERE MOISTURE DOES SEEM TO BE
MOVING UP THE RIDGE...LOW 90S IN KIT CARSON COUNTY ADVECTED WESTWARD
MAY GET HOT ENOUGH.  SE WYOMING AIR IS POTENTIALLY COOLER...PROBABLY
ENOUGH TO OFFSET SLIGHT COOLING ALOFT THAT MAY ACCOMPANY THIS
EVENINGS SHORT WAVE.  SO...RATHER DRY CONVECTION ALONG THE FOOTHILLS
NEXT 4-6 HOURS...QUESTIONABLE INTERACTION WITH THE MOIST AIR.  STILL
ENOUGH CAPE IN THE FRINGE AREA FOR SOME SEVERE THREAT...1500 J/KG OF
CAPE BALANCES NICELY WITH THE SHEAR.  FOR SATURDAY THE SCENARIO IS
SIMILAR...PERHAPS SOME DRYING AGAIN IN THE MOUNTAINS.  I WILL HANG
ON TO THE LOW LATE DAY POPS.     GIMMESTAD

LONG TERM DISCUSSION:  UPR HIGH REMAINS OVER THE DESERT SOUTHWEST
WITH A MDT NWLY FLOW OVR CO ON SATURDAY NIGHT.  INTERACTIVE
SOUNDINGS SHOW SUFFICIENT MSTR BUT WARMING DURING THE DAY SATURDAY
MAY INHIBIT DEEP CONVECTION...ESPECIALLY OUT IN THE NORTHEASTERN
PLAINS.  BEST SFC BASED THETA-E RIDGE IS PROGGED TO BE ALONG THE
FRONT RANGE.  INTERACTIVE CAPES SHOW VALUES OF 2500 J/KG WITH 87/54
T/TD VALUES...BUT AS MENTIONED EARLIER THERE IS STILL SOME LINGERING
CIN.  FOR NOW SLGT CHC FOR STORMS LOOKS GOOD.  ON SUNDAY...VERY
LITTLE CHANGE IS APPARENT IN THE OVERALL PATTERN BUT LESS MSTR WILL
BE PRESENT.  ON MONDAY...CONTINUED WARM BUT DRIER AS RIDGE FLATTENS
SOMEWHAT AND FLOW ALF BECOMES MORE WLY.  AS A RESULT...LOW LEVEL
THETA-E RIDGE SHIFTS FURTHER WHICH EFFECTIVELY SCOURS OUT THE MSTR.
WLY FLOW ALF WILL CONTINUE ON TUESDAY WITH LATEST AVN MOVING A SHORT
WAVE INTO WY AND NEBRASKA DURING THE AFTERNOON AND EVENING.  THETA-E
RIDGE IS PROGGED OVER THE NORTHEASTERN CORNER AS WELL.  FOR THIS
REASON WILL ADD A SLGT CHANCE OF THUNDERSTORMS TO THE FCST FOR
LATEST TUE AFTN AND EVENING.  WILL NOT MAKE ANY FURTHER CHANGES TO
THE EXTENDED AT THIS TIME. OVERALL POSITION OF THE HIGH DOES NOT
CHANGE TOO MUCH.  GFS MAINTAINS JUST ENUF MSTR UNDER THE RIDGE TO
WARRANT A SLGT CHANCE OF STORMS FOR WEDNESDAY AND MAYBE THURSDAY.
COOPER

.DEN...NONE.

COZ030>051-121200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
345 PM MDT FRI JUL 11 2003

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

.DAY ONE...TODAY AND TONIGHT

ONLY ISOLATED THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS AND
PLAINS OF EASTERN COLORADO THIS EVENING AND CONTINUE TONIGHT. OVER
MUCH OF EASTERN COLORADO THIS AFTERNOON...INSUFFICIENT HEATING HAS
RESULTED IN THE ATMOSPHERE REMAINING TOO STABLE FOR THUNDERSTORM
DEVELOPMENT. THERE IS A WEAK UPPER LEVEL SYSTEM ACROSS CENTRAL
WYOMING WHICH MAY ALLOW FOR ISOLATED THUNDERSTORM DEVELOPMENT LATER
THIS EVENING. THE EXCEPTION TO THE ABOVE IS ACROSS THE PALMER DIVIDE
AND ESPECIALLY LINCOLN COUNTY WHERE AMPLE HEATING HAS ALREADY
OCCURRED. ISOLATED THUNDERSTORMS HAVE DEVELOPED THERE AND THE THREAT
OF STORMS IS A LITTLE HIGHER OVER THE SOUTHERN PORTIONS OF ELBERT
AND LINCOLN COUNTIES.

THE HIGHEST THREAT OF SEVERE WEATHER WILL BE ON THE EDGE OF THE
BETTER MOISTURE FROM EASTERN WELD COUNTY SOUTHEAST TOWARD FORT
MORGAN...AKRON...AND LIMON.  THE MAIN THREAT FROM THESE STORMS WILL
BE LARGE HAIL AND DAMAGING WINDS...BUT TORNADOES ARE ALSO POSSIBLE.
STORMS THAT DO DEVELOP WILL GENERALLY BE AFTER 7 PM THIS EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A SLIGHT CHANCE OF THUNDERSTORMS CAN BE EXPECTED ON SATURDAY...SOME
POSSIBLY SEVERE.

SATURDAY MAY BRING ANOTHER RISK OF SEVERE WEATHER ACROSS THE
NORTHEAST PLAINS OF COLORADO...ALTHOUGH THE STORM COVERAGE WILL BE
LOWER.  SUNDAY THROUGH TUESDAY...THE AIRMASS WILL BE DRYING SO NO
THUNDERSTORM ACTIVITY IS ANTICIPATED BY MONDAY.  ENOUGH MOISTURE
WILL BE BACK IN THE AREA ON WEDNESDAY AND THURSDAY FOR A SLIGHT
CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 7 PM OVER THE EASTERN PLAINS.

GIMMESTAD/COOPER/SWE