Severe Thunderstorm Warning 107, NWS Pueblo, CO

SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO
154 PM MDT MON AUG 21 2000

...SEVERE WEATHER POTENTIAL THIS EVENING THE MAIN FORECAST CONCERN...

A COOL FRONT HAD PUSHED INTO SE CO AND WAS MAINLY BANKED UP ALONG
THE PALMER DIVIDE AS OF 1800 UTC...BUT LAPS POTENTIAL TEMPERATURE
ANALYSES INDICATED THAT A SHALLOW PORTION OF THE COOLER AIR HAD
SPILLED INTO THE ARKANSAS VALLEY WITH KLHX PICKING UP GUSTY NE
WINDS AS OF 1900 UTC.  THUNDERSTORMS WERE BEGINNING TO MOVE OFF
THE FOOTHILLS IN NE CO EARLY THIS AFTERNOON AND THIS COMBINED WITH
CONTINUED DIFFERENTIAL HEATING BETWEEN NE AND SE CO SHOULD HELP
PUSH A SHALLOW SURGE OF COOLER AIR INTO THE ARKANSAS VALLEY THIS
AFTERNOON AND ENHANCE THUNDERSTORM COVERAGE AND POTENTIAL
STRENGTH.  UPPER DISTURBANCES EMBEDDED IN THE MONSOONAL FLOW WILL
HELP KEEP SCATTERED THUNDERSTORMS GOING OVER THE WRN HALF OF THE
FORECAST AREA.  MID-LEVEL WINDS ARE NOT THAT STRONG (15-20 KTS AT
500 MB) BUT WITH THE COOL FRONT...DEEP LAYER SHEAR IS STILL AROUND 30
KTS.  CAPE IS LIKELY IN THE 1000-1500 J/KG RANGE...BUT THE 1900 UTC
LAPS ANALYSIS WAS IN EXCESS OF 2000 J/KG OVER THE FAR ERN
PLAINS.  ANYWAY...THE AMBIENT ENVIRONMENT ON THE PLAINS COULD SUPPORT
A FEW SEVERE STORMS THIS AFTN/EVE. FOR NOW...I'M NOT SURE WHEN TO END
THE PRECIPITATION IN THE FORECAST...SO I MAY JUST LEAVE GENERIC
WORDING IN THE ZONES WITH NO PRECIPITATION TIMERS. APPARENTLY...THE
SUN ANGLE IS LOW ENOUGH THAT THE SAN LUIS VALLEY WILL GET FOG EACH
NIGHT WHEN PRECIPITATION FALLS IN THE DAYTIME...SO I'LL THROW SOME
PATCHY FOG IN TONIGHT.

ON TUESDAY/TUESDAY NIGHT...LOW LEVEL MOISTURE WILL STILL BE POOLED IN
THE ARKANSAS VALLEY/SE PLAINS AREA...WITH THE "MONSOONAL" MOISTURE
PLUME CONTINUING OVERHEAD...SO "CHANCE" POPS WILL BE IN ORDER
THERE...WITH "SLIGHT CHANCE" POPS ELSEWHERE.  THE BEST CHANCES SHOULD
BE ALONG AND NEAR THE E SLOPES...IN THE PROXIMITY OF THE TRIPLE POINT
OF WEAK UPPER DISTURBANCES MOVING THROUGH THE FLOW...OROGRAPHIC LIFT
AND DEEP MOISTURE.  MAXIMUM TEMPERATURES SHOULD BE SIMILAR TO TODAY
IN MOST AREAS.

WEDNESDAY...THE UPPER HIGH BROADENS AND BUILDS INTO THE NRN GREAT
BASIN/NRN ROCKIES BEHIND THE EXITING SHORTWAVE ENERGY WITH THE
GENERAL "MONSOONAL" FLOW AROUND THE UPPER HIGH CONTINUING.  THUS...
TEMPERATURES SHOULD WARM BACK UP A FEW DEGREES ON THE PLAINS...WITH
LITTLE CHANGE ELSEWHERE. I WILL ALSO CONTINUE WITH THE BROAD-BRUSHED
LOW POP SCENARIO FOR THE ENTIRE AREA...GIVEN THE OVERALL PATTERN.

EXTENDED(THU-SAT): NOT MUCH CHANGE IN THE EXTENDED FORECAST...AS
THE MODELS CONTINUE WITH THE UPPER PATTERN ESTABLISHED ON
WEDNESDAY.  WHAT YOU SEE ON WEDNESDAY WILL BE PROBABLY BE WHAT YOU
GET DURING THIS PERIOD...MAINLY CONTINUED LOW POPS AND ABOVE NORMAL
DAYTIME TEMPERATURES.

.PUB...NONE.

HAYNES

COZ058>081-211900-

SIGNIFICANT WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PUEBLO CO
1155 AM MDT MON AUG 21 2000

...THE SIGNIFICANT WEATHER OUTLOOK FOR SOUTHEAST AND SOUTH CENTRAL
COLORADO...

...SPOTTER ACTIVATION MAY BE NEEDED FOR ONE OR TWO SEVERE
THUNDERSTORMS OVER THE PLAINS THIS AFTERNOON AND EVENING...

A COOL FRONT HAS PUSHED INTO SOUTHEAST COLORADO THIS MORNING...AND
HAS ALLOWED LOW LEVEL MOISTURE TO POOL OVER THE PLAINS.  IN
ADDITION...THE FRONT WILL PROVIDE A FOCUSING MECHANISM TO HELP
INITIATE THUNDERSTORMS...AND ALSO CONTRIBUTE TO VERTICAL WIND
SHEAR...WHICH WILL HELP ORGANIZE AND STRENGTHEN STORMS.

IN ADDITION...AN UPPER LEVEL DISTURBANCE CURRENTLY OVER WESTERN
COLORADO WILL MOVE ACROSS THE STATE TODAY...PROVIDING EXTRA SUPPORT
FOR THUNDERSTORM DEVELOPMENT. SCATTERED SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP OVER THE HIGHER TERRAIN BY EARLY THIS
AFTERNOON...AND MOVE OVER THE ADJACENT PLAINS THROUGHOUT THE
AFTERNOON AND EVENING. ONE OR TWO STORMS MAY BECOME SEVERE OVER THE
PLAINS THIS AFTERNOON AND EVENING...WITH THE PRIMARY THREAT OF SEVERE
WEATHER BEING HAIL AROUND ONE INCH IN DIAMETER...AND STRONG...GUSTY
WINDS IN EXCESS OF 60 MPH.

COZ067-071>073-212250-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PUEBLO CO
416 PM MDT MON AUG 21 2000

...STRONG THUNDERSTORMS DEVELOPING OVER EL PASO COUNTY...

STRONG THUNDERSTORM WILL CONTINUE TO DEVELOP OVER EL PASO COUNTY
THIS AFTERNOON AND EVENING. STORMS WIL LPRODUCE HAIL UP TO ONE HALF
INCH IN DIAMETER...WIND GUSTS OF 40 TO 50 MPH AND HEAVY RAIN. THE
STORMS WILL ALSO PRODUCE FREQUENT CLOUD TO GROUND LIGHTNING. STORMS
WILL FIRST MOVE OVER NORTHERN COLORADO SPRINGS ACROSS GARDEN OF THE
GODS TO MANITOU SPRINGS. THEY WILL MOVE EAST AT 40 MPH.

IT IS POSSIBLE THSES STORMS WILL DEVELOP INTO SEVERE THUNDERSTORMS
OVER THE COLORADO SPRINGS AREA WITH LARGE HAIL AND VERY STRONG WIND
GUSTS.

FORTUNE