Hail in Colorado, June 12, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO CO
301 PM MDT FRI JUN 12 2009

.SHORT TERM...
(TONIGHT AND SATURDAY)

POTENTIAL FOR SEVERE STORMS IS THE MAIN CONCERN. THIS AFTERNOON DEW
POINTS ARE IN THE 50S OVR THE FAR SE PLAINS...AND HAVE DROPPED
INTO THE UPPER 30S TO LOWER 40S ALONG THE I25 CORRIDOR. A BOUNDARY
BETWEEN THE REALLY MOIST AND DRIER AIR IS LYING ACRS THE NE CORNER
OF EL PASO COUNTY AND WL HAVE TO CLOSELY WATCH THIS BOUNDARY FOR
POTENTIALLY SEVERE STORMS. SHOULD ALSO SEE ISOLD TO SCT STORMS
THIS EVENING ACRS MUCH OF THE AREA. WITH THE BEST LOW LEVEL MSTR
BEING OVR PORTIONS OF SE CO...ALONG WITH DEEP LAYER SHEAR VALUES
OF 45-60 KTS THERE WL BE THE POTENTIAL FOR SEVERE STORMS ALL ACRS
THE SE PLAINS THIS EVENING. BY LATE TONIGHT THE TSTMS SHOULD END.
THE NAM AND THE GFS KEEP SOME SHOWERS OVR PORTIONS OF THE SE
PLAINS. WITH THE NAM SHOWING INCREASING RH AT 850MB LATER
TONIGHT...EXPECT LOW CLOUDS TO COVER MUCH OF THE SE PLAINS. WITH
THE LOW LEVEL UPSLOPE FLOW...COULD SEE SOME LIGHT
PCPN...ESPECIALLY ALONG THE SLOPES OF THE SE MTS...OUT TO ALONG
THE I25 CORRIDOR. ON SATURDAY THE UPR RIDGE OVR THE AREA WL SHIFT
EWRD AS AN UPR TROF MOVES OVR CA AND NV WHICH WL ALSO INCREASE THE
SW FLOW ALOFT OVR THE AREA. MEANWHILE...AT THE SFC THE LOW LEVEL
SE WINDS OVR THE SE PLAINS WL ALSO BE INCREASING. THE NAM SHOWS
SFC DEW POINTS IN THE 50S TO LOWER 60S ACRS ALL THE SE PLAINS THRU
THE AFTERNOON SATURDAY...WHILE THE GFS SHOWS 50S OVR THE FAR SE
PLAINS...AND 40S OVR PUEBLO AND EL PASO COUNTIES...WITH DRIER AIR
WORKING INTO THE SE FOOTHILLS WITH INCREASED SW FLOW. THE NAM
SHOWS CAPE VALUES OF AROUND 1000 J/KG IN THE AFTERNOON WITH DEEP
LAYER SHEAR VALUES OF 40-50 KTS. THE LOW CLOUDS ARE EXPECTED TO
LINGER OVR MUCH OF THE SE PLAINS THRU THE MORNING AND EVEN INTO
THE EARLY AFTERNOON IN SOME AREAS...WHICH IF THIS HAPPENS...WL
IMPACT THE STABILITY. STILL LOOKING FOR ISOLD TO SCT TSTMS TO
DEVELOP AND WITH THE AFOREMENTIONED CONDITIONS...THERE SHOULD BE
THE POTENTIAL FOR SEVERE STORMS OVR THE SE PLAINS.

.LONG TERM...
(SATURDAY NIGHT THROUGH FRIDAY)

ACTIVE PATTERN CONTINUES WITH THE MAIN CHALLENGE BEING SEVERE
THUNDERSTORM POTENTIAL SOMEWHERE ACROSS THE EASTERN PLAINS OF CO
THROUGH AT LEAST THE WEEKEND.

UPPER PATTERN STILL DOMINATED BY RIDGING OVER THE CENTRAL PART OF
THE US WITH TROFING ACROSS THE WEST.  SEVERAL SHORTWAVES RIDING
THROUGH SOUTHWEST FLOW ALOFT WILL PROVIDE UPPER LEVEL FORCING FOR
SCATTERED THUNDERSTORMS ACROSS THE MOUNTAINS AND ADJACENT PLAINS.
NEXT WAVE IN PV FIELDS MOVES ACROSS THE STATE SAT EVENING...AND WITH
PLENTY OF LOW LVL MOISTURE ACROSS THE PLAINS...CAPES WILL BE RUNNING
AROUND 1000-1500 J/KG ASSUMING WE GET ENOUGH SFC HEATING. DEEP LAYER
SHEARS RUNNING AROUND 40-50 KTS...AND NAM SFC ANALYSIS AT 03Z SUN
INDICATES A SFC CYCLONE SETTING UP AGAIN JUST NORTH OF THE RATON
RIDGE PULLING SFC WINDS MORE EASTERLY ACROSS THE LOWER ARKANSAS
RIVER BASIN. CONDITIONS LOOK SIMILAR TO YESTERDAY...THOUGH IF NAM
IS CORRECT THE SFC DEW POINTS WILL BE HIGHER...LEADING TO GREATER
POTENTIAL INSTABILITY. NAM EVEN HAS 0-1KM HELICITIES OF OVER
300-400 M2/S2 JUST NORTH OF THE RATON RIDGE. ALL THIS SPELLS A
CHANCE FOR SEVERE TSTORMS WITH LARGE HAIL...DAMAGING WINDS AND
EVEN AN ISOLATED TORNADO POSSIBLE FRIDAY EVENING. ONCE AGAIN...NAM
CONGEALS ACTIVITY INTO AN MCS ACROSS EAST CENTRAL CO DURING THE
EVENING WHICH SHIFTS EASTWARD INTO KS OVERNIGHT. MAIN CHANGE TO
GRIDS WAS TO INCREASE POPS FOR SAT.

ANOTHER SHORTWAVE MOVES ACROSS ON SUNDAY AND THE FRONTAL BOUNDARY
APPEARS TO MAKE A BETTER PUSH NORTHWARD...THOUGH ITS ULTIMATE
POSITION IN THE AFTERNOON WAVERS NORTH TO SOUTH A BIT EACH RUN.
COULD SEE SOME SEVERE THUNDERSTORMS AGAIN ACROSS NORTHERN PORTIONS
OF THE SE PLAINS...MAINLY PALMER DIVIDE NORTHWARD.

FLOW ALOFT BECOMES MORE SOUTH TO SOUTHWESTERLY NEXT WEEK AS NEXT
UPPER LOW MOVES TOWARDS THE SOUTHWEST US. LATEST MODELS STILL
WAVER THE FRONT IN AND OUT OF THE SOUTHEAST PLAINS...THOUGH
APPEARS THE FRONT LIFTS BACK NORTHWARD EACH AFTERNOON WITH
SOUTHEAST COLORADO IN THE DRY SECTOR. THUS...A WARMING AND DRYING
TREND LIKELY FOR EARLY NEXT WEEK. A NORTHERN STREAM TROF MAY MOVES
THROUGH THE NRN U.S. ROCKIES WED NIGHT SENDING A WEAK SFC HIGH
THROUGH THE PLAINS ON THURS. HOWEVER...FOR NOW TEMPERATURES DO NOT
LOOK ALL THAT MUCH COOLER BEHIND THE FRONT. -KT

&&

.AVIATION...VFR CONDITIONS SHOULD PERSIST AT THE TAF SITES THROUGH
THE EVENING.  HOWEVER THUNDERSTORMS IN THE KCOS AREA COULD CAUSE
BRIEF MVFR CONDITIONS.  LATER TONIGHT LOW CLOUDS WL SPREAD ACRS THE
SE PLAINS...WITH IFR CIGS DEVELOPING AT KCOS AND KPUB...AND VFR
CONDITIONS AT KALS.  THE LOW CLOUDS MAY BE SLOW TO DISSIPATE ON
SATURDAY AT KCOS...WHILE KPUB WL LIKELY SEE A RETURN TO VFR
CONDITIONS BY LATE MORNING.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

28/31

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PUEBLO CO
430 PM MDT FRI JUN 12 2009

COZ058>089-093>099-132230-
WESTERN MOSQUITO RANGE/EAST LAKE COUNTY ABOVE 11000 FT-
LEADVILLE VICINITY/LAKE COUNTY BELOW 11000 FT-
EASTERN SAWATCH MOUNTAINS ABOVE 11000 FT-
WESTERN CHAFFEE COUNTY BETWEEN 9000 AND 11000 FT-
CENTRAL CHAFFEE COUNTY BELOW 9000 FT-
WESTERN MOSQUITO RANGE/EAST CHAFFEE COUNTY ABOVE 9000 FT-
SAGUACHE COUNTY WEST OF CONTINENTAL DIVIDE BELOW 10000 FT-
SAGUACHE COUNTY EAST OF CONTINENTAL DIVIDE BELOW 10000 FT-
LA GARITA MOUNTAINS ABOVE 10000 FT-
UPPER RIO GRANDE VALLEY/EASTERN SAN JUAN MOUNTAINS BELOW 10000 FT-
EASTERN SAN JUAN MOUNTAINS ABOVE 10000 FT-
DEL NORTE VICINITY/NORTHERN SAN LUIS VALLEY BELOW 8500 FT-
ALAMOSA VICINITY/CENTRAL SAN LUIS VALLEY BELOW 8500 FT-
SOUTHERN SAN LUIS VALLEY-
NORTHERN SANGRE DE CRISTO MOUNTAINS BETWEEN 8500 AND 11000 FT-
NORTHERN SANGRE DE CRISTO MOUNTAINS ABOVE 11000 FEET-
SOUTHERN SANGRE DE CRISTO MOUNTAINS BETWEEN 7500 AND 11000 FT-
SOUTHERN SANGRE DE CRISTO MOUNTAINS ABOVE 11000 FT-
NORTHWESTERN FREMONT COUNTY ABOVE 8500 FT-
WESTERN/CENTRAL FREMONT COUNTY BELOW 8500 FT-
WET MOUNTAIN VALLEY BELOW 8500 FEET-
WET MOUNTAINS BETWEEN 6300 AND 10000 FT-
WET MOUNTAINS ABOVE 10000 FT-
TELLER COUNTY/RAMPART RANGE ABOVE 7500 FT/PIKES PEAK BETWEEN
7500 AND 11000 FT-PIKES PEAK ABOVE 11000 FT-
CANON CITY VICINITY/EASTERN FREMONT COUNTY-
NORTHERN EL PASO COUNTY/MONUMENT RIDGE/RAMPART RANGE BELOW
7500 FT-
COLORADO SPRINGS VICINITY/SOUTHERN EL PASO COUNTY/RAMPART RANGE
BELOW 7400 FT-PUEBLO AND VICINITY/PUEBLO COUNTY BELOW 6300 FT-
WALSENBURG VICINITY/UPPER HUERFANO RIVER BASIN BELOW 7500 FT-
TRINIDAD VICINITY/WESTERN LAS ANIMAS COUNTY BELOW 7500 FT-
CROWLEY COUNTY-LA JUNTA VICINITY/OTERO COUNTY-
EASTERN LAS ANIMAS COUNTY-WESTERN KIOWA COUNTY-
EASTERN KIOWA COUNTY-LAS ANIMAS VICINITY/BENT COUNTY-
LAMAR VICINITY/PROWERS COUNTY-SPRINGFIELD VICINITY/BACA COUNTY-
430 PM MDT FRI JUN 12 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL...EAST
CENTRAL...SOUTH CENTRAL AND SOUTHEAST COLORADO.

.DAY ONE...TONIGHT

A FEW STORMS THIS EVENING OVER THE PALMER DIVIDE AND EASTERN PLAINS
WILL BECOME SEVERE...PRODUCING HAIL UP T0 TWO INCHES IN
DIAMETER...WIND GUSTS IN EXCESS OF 60 MPH...AND POSSIBLY A
SHORT-LIVED TORNADO.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED SATURDAY
AND SUNDAY ACROSS MUCH OF THE AREA. SOME OF THE STORMS COULD BE
SEVERE WITH LARGE HAIL...DAMAGING WINDS AND DANGEROUS LIGHTNING.
AN ISOLATED TORNADO IS ALSO POSSIBLE.

ONLY ISOLATED THUNDERSTORMS ARE EXPECTED MONDAY THROUGH THURSDAY.
THE STORMS WILL DEVELOP OVER THE MOUNTAINS AND MOVE ONTO THE
PLAINS DURING THE AFTERNOON. SMALL HAIL...GUSTY WINDS AND
LIGHTNING ARE POSSIBLE WITH ANY OF THE THUNDERSTORMS.

.SPOTTER INFORMATION STATEMENT...
WEATHER CONDITIONS THAT MEET REPORTING CRITERIA FOR SPOTTERS WILL BE
POSSIBLE OVER THE SOUTHEAST PLAINS UNTIL 11 PM TODAY.

06/44