Severe Thunderstorm Warning 40, NWS Pueblo, CO

SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO COLORADO
212 PM MDT WED MAY 30 2001

...FORECAST CHALLENGE WILL BE EXTENT OF SEVERE WEATHER THIS EVENING
ACROSS SOUTH CENTRAL PORTION OF FORECAST AREA...

NORTHERLY SURGE PUSHED THROUGH ALL OF SOUTHEAST PLAINS.
DEW POINTS BEHIND THE SURGE STILL REMAIN IN THE UPPER 40S TO LOWER
50S.  SHORTWAVE IN SATELLITE PICS NOW IN NORTHWEST COLORADO WILL
ADVANCE SOUTHEASTWARD IN NORTHWEST FLOW. RUC40 AND 12Z MESO ETA STILL
INDICATING THE BEST THREAT FOR SEVERE THUNDERSTORMS TO BE ALONG THE
SOUTHEAST MOUNTAINS FROM AROUND PUB SOUTH AND EASTWARD. LAPS SHOWING
CAPES OF 1000-1500 J/KG AND 0-6KM SHEARS OF AROUND 40 KTS.  A
SUPERCELL WOULD NOT BE OUT OF THE QUESTION GIVEN THE SHEARS.  SPC
HAS ISSUED SVR WATCH FOR PORTION OF SOUTHEAST PLAINS...WITH
HAIL PRIMARY THREAT.   THUNDERSTORMS SHOULD DIMINISH BY MID EVENING
AS ACTIVITY SHIFTS SOUTHEASTWARD AHEAD OF SHORTWAVE.

THURSDAY/THURS NIGHT...UPPER RIDGE AXIS SHIFTS EASTWARD WITH AVN
STILL HINTING AT A WEAK SHORTWAVE CURRENTLY OVER OR/NRN CA ROUNDING
TOP OF RIDGE AND MOVING ACROSS WESTERN AND SOUTHERN PORTIONS OF THE
FORECAST AREA THURSDAY AFTERNOON.  NOT MUCH QG ASCENT WITH THIS
FEATURE...AND EVEN PV FIELDS NOT PICKING UP ON IT.  ATMOSPHERE
REMAINS FAIRLY DRY IN WESTERN SECTIONS OF THE FORECAST AREA...SO
LITTLE INFLUENCE HERE.  ENOUGH LINGERING MOISTURE AND ANOTHER
NORTHERLY SURGE TO MAINTAIN SLIGHT CHANCE POPS IN AND NEAR SOUTHEAST
MOUNTAINS.  ON THE SOUTHEAST PLAINS...MESO ETA HINTS AT A WEAK
CONVERGENCE ZONE AHEAD OF NORTHERLY SURGE...WITH DEW POINTS IN THE
UPPER 40S TO LOWER 50S...AND CAPES OF 400-700 J/KG. CONVECTIVE
TEMPERATURES WILL BE AROUND 80.  ANY CONVERGENCE ALONG THIS BOUNDARY
COULD ALSO HELP INITIATE THUNDERSTORMS.  WILL THROW IN SOME 20 POPS
ACROSS SOUTHEAST PLAINS.  0-6KM SHEAR IS AROUND 35-40KTS BUT
INSTABILITY ISNT ALL THAT IMPRESSIVE SO SEVERE THREAT LOOKS PRETTY
MINIMAL YET.  700 TEMPS WARM ABOUT 2 DEGREES CELSIUS...SO IT SHOULD
WARM UP ABOUT A CATEGORY ABOVE TODAYS HIGHS.  GOING ZONES LOOK GOOD
ALTHOUGH MAY TWEEK TEMPS DOWN A BIT IN SOUTHEAST PLAINS.
THUNDERSTORMS SHOULD DIMINISH IN THE EVENING. GUIDANCE LOW TEMPS
LOOK GOOD.

FRIDAY/FRI NIGHT...UPPER RIDGE OF HIGH PRESSURE CONTINUES TO SHIFT
EAST WITH SHALLOW COLD FRONT MOVING THROUGH SOUTHEAST PLAINS IN THE
AFTERNOON IN WAKE OF UPPER LOW MOVING THROUGH GREAT LAKES REGION
INTO NRN IL. ITS ASSOCIATED 100KT UPPER JET DIVES DOWN CENTRAL
PLAINS. AVN IS MUCH STRONGER WITH THIS SFC SURGE THAN ETA...PROBABLY
A RESULT OF THE SLIGHTLY FASTER AND FURTHER SOUTH MOVEMENT OF UPPER
TROUGH.  STILL LOOKS PRETTY DRY...EVEN ACROSS SOUTHEAST PLAINS SO
WILL MAINTAIN GOING DRY FORECAST.   IN SPITE OF COLD FRONT PASSAGE...
TEMPERATURES BEHIND THE FRONT ARE NOT ALL THAT COOL.  UPPER RIDGE
SHIFTING OVER AREA WARM 700 TEMPS TO +10 IN THE EAST TO +17 IN THE
WEST. WITH GOOD MIXING...TEMPERATURES SHOULD WARM INTO THE 80S
ACROSS MUCH OF THE SOUTHEAST PLAINS.

EXTENDED...

SATURDAY...UPPER RIDGE CONTINUES TO SHIFT EASTWARD INTO CENTRAL
PLAINS AS NEXT SHORTWAVE IN BC CUTS DOWN UPPER RIDGE AS IT MOVES
INTO THE NRN ROCKIES BY SUNDAY MORNING. ANOTHER WARM AND DRY DAY FOR
SATURDAY...THEN UPPER TROUGH MOVES THROUGH NRN ROCKIES ON SUNDAY
WITH ANOTHER COLD FRONT MOVING THROUGH SOUTHEAST PLAINS SUNDAY
NIGHT. WILL BREAK OUT SUNDAY TO ADD SOME SHOWERS AND THUNDERSTORMS
INTO SOUTHEAST PLAINS AREAS.  ELSEWHERE REMAINS DRY.   ANOTHER UPPER
RIDGE SHIFTS EASTWARD FOR MONDAY THEN TRANSITIONS EASTWARD THROUGH
THE END OF THE WEEK WITH TEMPERATURES WARMING AGAIN ON SOUTHEAST
PLAINS THROUGH THE END OF THE PERIOD.

.PUB...NONE.

KT

COZ058>081-301900-

SIGNIFICANT WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PUEBLO CO
1144 AM MDT WED MAY 30 2001

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

...SPOTTER ACTIVATION MAY BE NECESSARY THIS AFTERNOON FOR ONE OR TWO
MARGINALLY SEVERE THUNDERSTORMS ALONG THE INTERSTATE 25 CORRIDOR
SOUTH OF PUEBLO...

AN UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE ACROSS SOUTH
CENTRAL...AND SOUTHEAST COLORADO THIS AFTERNOON.  COMBINED WITH
WEAK NORTHEAST UPSLOPE FLOW...AND RESIDUAL LOW LEVEL
MOISTURE...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON ACROSS THE SOUTHEAST MOUNTAINS AND PLAINS.
THE ATMOSPHERE WILL BECOME MOST UNSTABLE ALONG THE EAST SLOPES
OF THE WET MOUNTAINS AND THE SANGRE DE CRISTO MOUNTAINS...
AND THE ADJACENT PLAINS SOUTHWEST OF A LINE FROM PUEBLO TO KIM.
MODERATE INSTABILITY...COMBINED WITH FAVORABLE WIND SHEAR...MAY LEAD
TO THE DEVELOPMENT OF ONE OR TWO MARGINALLY SEVERE THUNDERSTORMS IN
THIS AREA...WITH HAIL AROUND 3/4 INCH IN DIAMETER AND GUSTY WINDS TO
AROUND 58 MPH THE PRIMARY THREATS.

ELSEWHERE...THUNDERSTORMS ARE EXPECTED TO BE WEAKER...HOWEVER...HAIL
UP TO 1/2 INCH IN DIAMETER...GUSTY WINDS TO 40 MPH AND FREQUENT
LIGHTNING WILL BE POSSIBLE...ESPECIALLY IN THE PIKES PEAK REGION.

THE NATIONAL WEATHER SERVICE IN PUEBLO WOULD APPRECIATE ANY HAIL
REPORTS FROM ITS SPOTTERS ACROSS SOUTHEAST COLORADO THIS AFTERNOON.