Severe Thunderstorm Warning 78, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
300 PM MDT THU AUG 29 2002

TONIGHT:  PLENTY OF SYNOPTIC SCALE ENERGY IS VISIBLE ON THE WATER
VAPOR AND RADAR PICTURES UPSTREAM. THE ENERGY IS JUST STARTING TO
MAKE IT ONTO THE PLAINS OF THE FORECAST AREA.  AREA PROFILERS SHOW A
60 PLUS KNOW SOUTHWESTERLY JET OVER THE AREA RIGHT NOW.  THIS IS
PROGGED ACROSS THE FORECAST AREA UNTIL ABOUT 03/06Z THEN THE UPPER
TROUGH AXIS PUSHES ACROSS.  RADAR IS INDICATING A DECENT CONVERGENCE
LINE STRETCHED NORTH AND SOUTH OVER THE EASTERN METRO AREA AT THIS
TIME.  50S TO LOWER 60S DEW POINTS ARE IN PLACE OVER ALL THE PLAINS
RIGHT NOW.  THIS WITH ALL THE DYNAMIC ENERGY TO MOVE ACROSS...POPS
SHOULD BE PRETTY WIDESPREAD OVER THE PLAINS AND THEY SHOULD BE SLOW
TO DISSIPATE WAY INTO THE NIGHTTIME HOURS.

FRIDAY THROUGH SUNDAY:  TONIGHT UPPER TROUGH AXIS WILL BE OVER
EASTERN COLORADO BY FRIDAY MORNING AT 12Z.  DOWNWARD FORCING IS
PROGGED IN THE SYNOPTIC SCALE ON FRIDAY.  THE UPPER RIDGE BUILDS
BACK INTO THE FORECAST AREA AND THE CROSS SECTIONS SHOW WARMING AND
A STRONG STABLE LAYER AT THE MID LEVELS.  BY FRIDAY NIGHT THE UPPER
RIDGE AXIS SHIFTS EAST OF THE FORECAST AREA WITH SOUTHWESTERLY FLOW
ALOFT EXPECTED FOR SATURDAY.  CROSS SECTIONS SHOW STEEPER LAPSE
RATES ON SATURDAY AFTERNOON. GRIDS SHOW A JET MAX OF SOUTHWESTERLY
WINDS OVER THE FORECAST AREA EARLY SUNDAY MORNING THROUGH AFTERNOON.
BY SUNDAY AFTERNOON ANOTHER UPPER TROUGH MOVES INTO WESTERN
COLORADO.  GRIDS SHOW WEAK SYNOPTIC SCALE ASCENT ON SATURDAY...THEN
BETTER ENERGY FOR SUNDAY AFTERNOON IN FRONT OF THE APPROACHING
TROUGH.  THE LAPSE RATES ARE PRETTY STEEP AGAIN SUNDAY AFTERNOON.
CONCERNING MOISTURE...GRIDS SHOW THE LOW LEVEL MOISTURE JUST EAST OF
THE FORECAST AREA FOR FRIDAY AFTERNOON...GETTING BACK INTO THE
EXTREME EASTERN FORECAST AREA FOR SATURDAY...THEN FLUSHING WAY EAST
FOR SUNDAY AFTERNOON.  CROSS SECTIONS DO INDICATE SOME MID/UPPER
LEVEL MOISTURE FRIDAY EVENING...AGAIN SATURDAY MIDDAY IN THE
EVENING...BUT LITTLE ON SUNDAY.  MAY PUT SOME LIMITED POPS IN A FEW
APPROPRIATE AREAS FOR THE THREE AFTERNOONS.   CONCERNING
TEMPERATURES...GRIDS SHOW A 1-2 C WARM-UP FOR FRIDAYS HIGHS...A BIT
WARMER ON SATURDAY...THEN A 1-2 C COOL DOWN ON SUNDAY.

IN THE EXTENDED PERIOD: MONDAY THROUGH THURSDAY...THE MODELS SHOW
THE UPPER RIDGE CENTERED STILL TO THE SOUTHWEST OF THE FORECAST AREA
WITH AN UPPER TROUGH MOVING EASTWARD NORTH OF COLORADO.  BY TUESDAY
THE MODELS SHOW THE UPPER RIDGE BUILDING BACK INTO THE FORECAST
AREA.  WEDNESDAY AND THURSDAY SHOW ANOTHER WEST COAST TROUGH HELP TO
BRING SOUTHWESTERLY FLOW ALOFT TO THE FORECAST AREA.  GRIDS BRING IN
A LOW LEVEL COLD FRONT MONDAY AFTERNOON AND EVENING.  GRIDS SHOW
VARYING AMOUNTS OF MOISTURE THROUGH THE PERIOD...BUT THEY LEAN
TOWARDS THE DRY END.  I WILL LEAVE THE SLIGHT CHANCE GOING FOR
NOW.     RJK

.DEN...NONE.

COZ030>051-292000-

HAZARDOUS WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1000 AM MDT THU AUG 29 2002

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE  BOULDER     BROOMFIELD  CLEAR CREEK  DENVER
DOUGLAS   ELBERT    GILPIN      GRAND       JACKSON      JEFFERSON
LARIMER   LINCOLN   LOGAN       MORGAN      PARK         PHILLIPS
SEDGWICK  SUMMIT    WASHINGTON  WELD

SYNOPSIS: A MOIST AND UNSTABLE AIRMASS WILL CONTINUE ACROSS NORTH
CENTRAL AND NORTHEASTERN COLORADO TODAY.  AN UPPER LEVEL TROUGH IS
EXPECTED TO BRUSH ACROSS NORTHERN COLORADO LATE THIS AFTERNOON AND
TONIGHT.  THE LIFT FROM THIS SYSTEM...COUPLED WITH AFTERNOON HEATING
...WILL ALLOW FOR SCATTERED THUNDERSTORMS TO DEVELOP ACROSS MUCH OF
THE AREA THIS AFTERNOON AND EVENING.

SUFFICIENT SHEAR WILL BE PRESENT FOR A FEW SEVERE THUNDERSTORMS
...SIMILAR TO WHAT HAS OCCURRED OVER THE PAST FEW DAYS.  CLOUD COVER
MAY AGAIN DELAY THE ONSET OF THE STRONGER STORMS UNTIL THE UPPER
TROUGH MOVES INTO THE REGION LATE THIS AFTERNOON.

THE BEST POTENTIAL FOR SEVERE WEATHER WILL OCCUR JUST TO THE EAST OF
THE URBAN CORRIDOR...WHERE THE BEST POOL OF LOW LEVEL MOISTURE
RESIDES.  LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAIN WILL BE
THE MAIN THREATS.  A FEW WEAK TORNADOES MAY ALSO OCCUR ALONG ANY
COLLIDING OUTFLOW BOUNDARIES.

SPOTTER ACTIVATION MAY BE NECESSARY AFTER 3 PM.

OUTLOOK FOR FRIDAY...WARMER AND MUCH DRIER.

COOPER

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
255 PM MDT THU AUG 29 2002

...PRELIMINARY STORM REPORT FOR AUGUST 29 2002...

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0250 PM    1 S EVERGREEN             CO   1.00 INCH HAIL
08/29/02   JEFFERSON

RAY