Severe Thunderstorm Warning 86, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
308 PM MDT SUN JUN 27 1999

FAIRLY DECENT EAST-SOUTHEAST LOW LEVEL FLOW OVER THE PLAINS AT THIS
TIME....WITH PLENTY OF UPPER 50S DEW POINTS EVERYWHERE.  LAPS DATA
SHOWING A STRONG LOW LEVEL THETA-E AXIS OVER US...WITH THE BEST
MOISTURE CONVERGENCE PILING UP ALONG THE FOOTHILLS AND FRONT RANGE.
RADAR SHOWING SOME A DECENT BOUNDARY NORTH-SOUTH ACROSS DOUGLAS
COUNTY AND AREA OBSERVATIONS ARE HINTING AT A DENVER CYCLONE SETTING
UP.  SATELLITE PICTURES ARE SHOWING A BOUNDARY ACROSS THE NORTHEAST
CORNER OF THE PLAINS...AND SOMETHING ALONG THE CHEYENNE RIDGE...WITH
ONLY MINIMAL CUMULUS DEVELOPMENT AT THIS TIME OVER THE CWA.  SOME
CONVECTION GOING NORTH OF THE BORDER IN WYOMING AND NEBRASKA...BUT
NONE YET HERE.  TROUBLE IS...NOT ABLE TO WARM ENOUGH YET TO BREAK
THE INVERSIONS ABOVE US.  LATEST ACARS SOUNDINGS STILL SHOWING
STRONG 700 MB CAP OVER THE AREA...AND A LITTLE ONE AT ABOUT 450 MB.
THE CAP WILL BE HARD TO GO AGAIN THIS AFTERNOON...BUT IF IT CAN
...LAPS SHOWING SOME 2000-4000 JOULES OF CAPE TO WORK WITH RIGHT
ALONG THE URBAN CORRIDOR AT THIS TIME.  WATER VAPOR PICTURES STILL
SHOWING THE UPPER TROUGH AXIS WELL UPSTREAM...WITH THE RUC/MESOETA
GETTING THEIR Q-G ASCENT/THERMAL TROUGH INTO HERE AFTER 00Z.  80-100
KNOT JET NOW IN THE AREA AS EVIDENT BY PROFILERS AND RAWS MOUNTAIN
WIND SENSORS.  THIS IS PROGGED TO CONTINUE OVERNIGHT.  I STILL THINK
WE'LL GET THE STORMS...SOME SEVERE TOO.

FOR MONDAY THROUGH TUESDAY...FAIRLY STRONG WEST-NORTHWESTERLY FLOW
ALOFT IS PROGGED...WITH THE DIV-Q/POTENTIAL VORTICITY/UPPER WIND
GRIDS SHOWING SOME VERY WEAK SYNOPTIC SCALE LIFT FROM TIME TO TIME.
WATER VAPOR PICTURE PROGS WOULD BE NICE FOR LOCATING THESE
FEATURES.  THE LOW LEVEL PRESSURE/WIND/MOISTURE GRIDS KEEP SHOWING
SURGES MOVING INTO THE PLAINS...WITH THE NEXT ONE IN HERE AROUND 18Z
MONDAY NOONTIME...THEN ANOTHER IN LATE TUESDAY AFTERNOON/EVENING.
THEY ALSO KEEP AN EASTERLY COMPONENT TO THE LOW LEVEL FLOW
THROUGHOUT THE PERIOD...AND DECENT THETA-E AXES AT MANY LEVELS.
CROSS SECTIONS SHOW GREAT POTENTIAL INSTABILITY AS WELL AND MODIFIED
FORECAST SOUNDING SHOWING 2000 J/KG PLUS CAPES FOR THE PLAINS BOTH
DAYS.  THE WIND PROFILES SHOW BEST SHEAR FOR STORMS TUESDAY
AFTERNOON (SOUTHEAST SURFACE FLOW)...WITH MONDAY AFTERNOON IN THE
NORTHEAST LOW LEVEL FLOW.  THE LAPSE RATES ARE VERY STEEP BELOW 500
MB BOTH AFTERNOONS...BUT SOME 500/400 MB CAPPING INDICATED IN THE
TEMPERATURE GRIDS OFF AND ON THROUGH THE NEXT TWO DAYS.  WITH ALL
THE MOISTURE EXPECTED...EASTERLY FLOW...AND LATE EVENING MCS'S TO
CONTEND WITH...MORNING STRATUS IS A GOOD BET AS WELL.  BASICALLY IT
WILL BE MORE OF THE SAME...WITH PLENTY OF ENERGY AVAILABLE FOR
SEVERE WEATHER BUT TRYING TO FIGURE OUT THE MID LEVEL CAP SITUATION
... THE LOW LEVEL STABILIZATION OR NOT...AND ANY HELP FROM A
SYNOPTIC SCALE LIFTING MECHANISM OR NOT.  RIGHT NOW WILL GO WITH
SOME AFTERNOON/EVENING STORMS...MORE ON TUESDAY...AND MORNING
STRATUS.  TEMPERATURES WILL BE AT OR BELOW THE SEASONAL NORMS FOR
THE NEXT TWO DAYS.

FOR THE EXTENDED PERIOD...THE LAST 4 OR 5 MRF RUNS HAVE ALL SHOWN A
DECENT UPPER TROUGH OVER COLORADO AROUND WEDNESDAY...HOWEVER THE
LATEST RUN (06/27 00Z) NOW JUST INDICATES PRETTY DECENT WEST-
NORTHWEST FLOW ALOFT...NO TROUGH ANYMORE?  ANYWAY...THIS WEST-
NORTHWEST FLOW IS PROGGED THROUGH THE EXTENDED PERIOD WITH A COUPLE
OF SURGES OF UPSLOPE AT THE SURFACE.  WITH THE NORTHWEST FLOW
USUALLY HAVING PLENTY OF SYNOPTIC SCALE ENERGY EMBEDDED IN IT...AND
THE GRIDS SHOWING SOME MOISTURE OVER THE EASTERN HALF...WILL KEEP
"CHANCE" IN ALL THREE DAYS.     RJK

.DEN...NONE.

COZ050-280330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
900 PM MDT SUN JUN 27 1999

...TORNADO WATCH CANCELLED...

TORNADO WATCH NUMBER 484 FOR EASTERN SEDGWICK COUNTY IN NORTHEAST
COLORADO HAS BEEN CANCELLED AS OF 900 PM MDT THIS EVENING.

GARD...WFO BOULDER

COZ050-280330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
900 PM MDT SUN JUN 27 1999

...TORNADO WATCH CANCELLED...

TORNADO WATCH NUMBER 484 FOR EASTERN SEDGWICK COUNTY IN NORTHEAST
COLORADO HAS BEEN CANCELLED AS OF 900 PM MDT THIS EVENING.

GARD...WFO BOULDER