Severe Thunderstorm Warning 98, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
300 PM MDT TUE JUN 17 2003

SHORT TERM DISCUSSION:  THUNDERSTORM ACTIVITY IS BEGINNING TO SHIFT
ONTO THE PLAINS.  THE ENVIRONMENT IS SIMILAR TO YESTERDAY...BUT
WINDS ALOFT ARE SLIGHTLY HIGHER.  HENCE STORMS ARE MOVING AT 10 TO
15 MPH.  THIS WILL BE ENOUGH TO REDUCE THE FLASH FLOOD THREAT.
STORMS WILL PRODUCE INTENSE RAIN BUT FOR THE MOST PART WILL NOT STAY
OVER A GIVEN AREA FOR HOURS LIKE LAST NIGHT.  WE ARE ALSO LACKING
PLAINS WINDS TODAY...SO STORM MOTION SHOULD BE DOMINATED BY STEERING
FROM ABOVE.  THERE SHOULD BE LESS TENDENCY TO PUSH OUTFLOW BACK
TOWARD THE FOOTHILLS...SO WE SHOULD SEE A SLOW PROGRESSION EASTWARD
AND DWINDLING DURING THE NIGHT.  MAIN ADJUSTMENT TONIGHT WAS TO GO
WITH LIKELY POPS ON THE PLAINS.  FOR WEDNESDAY...NOT MUCH CHANGES.
THE ANTICIPATED DRYING SEEMS TO BE ON THE FRINGES...A LITTLE DRIER
IN THE WEST AND A BIT OF DRYING/WARMING AT MID LEVELS.  PLENTY OF
SURFACE MOISTURE SO THE NET EFFECT MIGHT BE A BIT OF A DELAY WAITING
FOR WARMER TEMPERATURES.  LIKELY POPS SEEM IN ORDER AGAIN FOR THE
MOUNTAINS AGAIN AND I WILL RAISE THE PLAINS POPS AS WELL.
GIMMESTAD

LONG TERM DISCUSSION:  TYPICAL DIURNAL PATTERN OF AFTN AND EVENING
SHOWERS AND THUNDERSTORMS LOOKS LIKE IT WILL CONT THRU THE END OF
THE WEEK AND INTO THE WEEKEND.  FOR THE REST OF THE WEEK...THE UPR
LVL RIDGE WL REMAIN IN PLACE OVR THE GREAT BASIN...KEEPING FLOW
ALOFT LIGHT AND WESTERLY.  AT LOWER LVLS...THERMALLY DRIVEN LOW PRES
AREA WL REMAIN ACRS THE GREAT BASIN WITH WEAK HIGH PRES OVR THE NRN
PLAINS.  CIRCULATION INTO THIS PATTERN WL FEED PERIODS OF GULF MSTR
AND INSTABILITY ACRS ERN CO.  DAYTIME HEATING WL BE ENOUGH FOR AFTN
CONVECTION TO DEVELOP OVR THE MTNS AND THEN PROGRESS OVR THE
ADJACENT PLAINS.

OVER THE WEEKEND...THE WRN U.S. UPR RIDGE WL BE REPLACED BY A STRONG
TROF MOVG IN FM THE ERN PAC.  THIS WILL INCRS THE SWLY FLOW ALOFT
ACRS THE RGN.  WHILE THE UPR TROF STAYS TO THE W OF US...LOW SFC
PRES WL ALSO CONT...ALLOWING LOW LVL MSTR AND INSTABILITY TO CONT
FEEDING INTO THE REGION.  HOWEVER...WITH STRONGER FLOW ALOFT...THE
SHEAR PROFILE MAY BE MORE FAVORABLE FOR STRONG STORM DEVELOPMENT.
THE LATEST MRF EJECTS THE UPR TROF ONTO THE CENTRAL PLAINS ABOUT
TUESDAY WITH A SFC CDFNT DROPPING ACRS NERN CO AT THAT TIME.
CONFIDENCE IN THE TIMING OF THIS FEATURE IS LOW...SO FOR NOW WL JUST
STICK WITH A PERSISTENCE FCST.  OTHERWISE TEMPS WL BE NEAR SEASONAL
VALUES.                                   KDRBY

.DEN...NONE.

COZ030>051-181200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1155 AM MDT TUE JUN 17 2003

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS WILL INCREASE OVER THE RIDGES AND EAST SLOPES OF THE
MOUNTAINS DURING THE EARLY AFTERNOON...THEN SPREAD ONTO THE PLAINS
DURING THE LATE AFTERNOON AND EVENING HOURS.  STORMS WILL BE SLOW
MOVING...WITH THE BIGGEST THREAT FROM STORMS BEING LOCALLY HEAVY
RAINFALL.  WHILE MOST STORMS ARE NOT EXPECTED TO PERSIST LONG ENOUGH
TO CAUSE SERIOUS FLOODING...A FEW OF THE STRONGER STORMS WILL BE
CAPABLE OF PRODUCING UP TO 2 INCHES OF RAIN IN JUST 45 MINUTES.
THIS COULD RESULT IN FLOODING PROBLEMS...ESPECIALLY IF IT OCCURS
OVER URBAN AREAS OR THE BURNED AREAS IN THE FOOTHILLS.  THERE IS
ALSO THE POTENTIAL FOR BRIEF PRODUCTION OF LARGE HAIL...BUT THE LACK
OF WIND SHEAR WILL KEEP THESE EVENTS ISOLATED.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS WILL CONTINUE OVER
THE ENTIRE FORECAST AREA THROUGH THE PERIOD.  AN UPPER LEVEL RIDGE
WILL CONTINUE OVER COLORADO THROUGH FRIDAY BEFORE AN UPPER TROUGH
PUSHES INTO THE FORECAST AREA SATURDAY AND SUNDAY.  MOISTURE LEVELS
WILL REMAIN HIGH ENOUGH THROUGH THE PERIOD TO ALLOW SHOWERS TO
DEVELOP OVER THE MOUNTAINS AND FOOTHILLS DURING EARLY AFTERNOONS AND
THEN MOVE ACROSS THE NORTHEAST PLAINS THROUGH THE EVENINGS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED TODAY.

GIMMESTAD/DANKERS

LOCAL STORM REPORT...CORRECTION
NATIONAL WEATHER SERVICE DENVER CO
228 PM MDT TUE JUN 16 2003

...PRELIMINARY STORM REPORT FOR JUNE 17 2003...

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

0226 PM    GREENLAND                 CO   1.00 INCH HAIL
06/17/03   DOUGLAS

RAY