Severe Thunderstorm Warning 136, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
245 PM MDT FRI JUL 18 2003

SHORT TERM DISCUSSION...CONVECTION FIRING OVER MOUNTAINS AND
FOOTHILLS...BUT HAVING A HARD TIME SURVIVING ONCE THEY MOVE ONTO
PLAINS.  LATEST ACARS SOUNDING SHOWING CAP ACROSS PLAINS...WITH
LAPS SURFACE DATA STILL INDICATING SOME CIN HANGING AROUND.  STORM
INITIATION ACROSS PLAINS WILL NEED A BOOST FROM OUTFLOW
INTERACTION.  SURFACE DATA DOES SHOW ANOTHER SURGE MOVING THROUGH
MORGAN AND WESTERN WASHINGTON COUNTIES...WHICH MAY ACT AS A TRIGGER
IF IT INTERACTS WITH ANY OUTFLOW.  WILL KEEP CURRENT POPS AS IS.
SHEAR WEAK...SO SEVERE UNLIKELY.  ANY CONVECTION SHOULD BE DONE BY
MIDNIGHT DUE TO LACK OF ANY UPPER SUPPORT.  MODELS SUGGEST SOME
LINGERING CLOUD COVER OVERNIGHT.  ON SATURDAY...MODELS SHOW RIDGE
RETROGRADES A BIT ALONG WITH SLIGHT COOLING ALOFT.  WINDS ALOFT
INCREASE SLIGHTLY WHICH INCREASES SHEAR A BIT.  WITH DECENT LOW
LEVEL MOISTURE IN PLACE ACROSS PLAINS...SO GOOD CHANCES FOR STORMS.
BUT CANNOT FIND MUCH UPSTAIRS TO AID IN ACTIVITY.  A FEW SEVERE
STORMS POSSIBLE EASTERN PLAINS WITH HAIL BIGGEST THREAT.  DECENT
PRECIPITABLE WATER VALUES...SO MEASURABLE RAINFALL LIKELY MOST
AREAS.  GUIDANCE TEMPS IN LINE WITH GRIDDED TEMP FCSTS.  D-L

LONG TERM DISCUSSION...SATURDAY NIGHT THROUGH MONDAY...A NWLY FLOW
ALF WILL BE OVER COLORADO...AS A RIDGE THAT HAS BEEN ANCHORED OVER
THE STATE...SHIFTS TO THE WEST.  FOR SATURDAY NIGHT...THE MDLS
MAINTAIN SUFFICIENT MSTR DURING THE LATE AFTN AND EVENING HOURS.
INTERACTIVE SOUNDINGS FM THE MESOETA INDICATE CAPES OF 2000-2500
J/KG WITH T/TD VALUES L90S/M50S.  MAY BE ENUF DIRECTIONAL SHEAR FOR
A FEW STRONG STORMS.  OVERALL THE PATTERN DOES NOT CHANGE TOO MUCH
ON MONDAY ALTHOUGH IT MAY BE SLIGHTLY DRIER.  ON TUESDAY ANOTHER
COLD FRONT IS EXPECTED TO MOVE INTO THE NERN PLAINS SO TEMPERATURES
WILL BE SLIGHTLY COOLER. THE RIDGE OVER THE WESTERN U.S. IS PROGGED
TO SHIFT E BACK OVER CO BY MIDWEEK AS ANOTHER SYSTEM MOVES INTO THE
PACIFIC NORTHWEST.  THE AIRMASS IS EXPECTED TO WARM UP AGAIN BY
WEDNESDAY BUT ENUF MSTR WILL BE PRESENT FOR A SLGT CHC OF STORMS
EACH DAY. COOPER

.DEN...NONE.

COZ030>051-191200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1102 AM MDT FRI JUL 18 2003

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND EVENING OVER
THE MOUNTAINS...WITH ISOLATED STORMS ON THE PLAINS.  THE STORMS WILL
BE SLOW MOVING AND A FEW OF THEM WILL PRODUCE HEAVY RAIN.  WARM HIGH
PRESSURE ALOFT WILL STILL LIMIT THE STRENGTH OF THUNDERSTORMS...BUT
STORMS ARE EXPECTED TO BE MORE NUMEROUS DUE TO INCREASING MOISTURE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS IS EXPECTED EACH
DAY.  THE HIGH PRESSURE ALOFT IS EXPECTED TO SHIFT WESTWARD...WHICH
WILL INCREASE THE POSSIBILITY OF STRONG THUNDERSTORMS ON THE
PLAINS.  THE BEST CHANCE FOR SEVERE WEATHER APPEARS TO BE SATURDAY
AND SUNDAY WITH LARGE HAIL AND HEAVY RAIN THE MAIN THREATS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.

D-L/FMC