000
FXUS65 KPUB 221759
AFDPUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO CO
1159 AM MDT WED MAY 22 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM MDT WED MAY 22 2013

CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
GENERALLY WEST TO SOUTHWEST FLOW ALOFT ACROSS THE REGION WITH
A LARGE UPPER LOW SPINNING ACROSS THE PAC NORTHWEST BUILDING AN
UPPER RIDGE FROM THE DESERT SOUTHWEST INTO THE ROCKIES AT THIS TIME.
WATER VAPOR IMAGERY ALSO INDICATING DRIER AIR ASSOCIATED WITH THE
BUILDING RIDGE MOVING INTO WESTERN COLORADO AT THIS TIME. TEMPS
EARLY THIS MORNING ARE WARMER THAN 24 HOURS AGO WITH MAINLY 30S
ACROSS THE HIGHER TERRAIN AND MAINLY 40S ACROSS THE EASTERN PLAINS
AT THIS TIME. WARMER AIR ASSOCIATED WITH THE BUILDING RIDGE NOT FAR
AWAY HOWEVER...WITH TEMPERATURES ACROSS EASTERN UTAH AND WESTERN
COLORADO IN THE 50S AT THIS TIME.

NOT MUCH CHANGE IN CURRENT FORECAST WITH WEAK WESTERLY FLOW ALOFT
ACROSS THE AREA TODAY. FLOW ALOFT BECOMES MORE SOUTHWEST AND
INCREASES THROUGH TONIGHT...WITH UPPER RIDGE BUILDING ACROSS THE
STATE AND INTO THE HIGH PLAINS AS PAC NORTHWEST LOW SLOWLY MOVES
EASTWARD. DRIER AIR ALOFT CONTINUES TO MOVE ACROSS THE AREA THOUGH
SHOULD STILL BE ENOUGH MOISTURE ALONG WITH LATE SPRING SUNSHINE FOR
ISOLATED LATE AFTERNOON AND EARLY EVENING SHOWERS AND THUNDERSTORMS
OVER AND NEAR THE THE HIGHER TERRAIN...WITH BEST COVERAGE AGAIN
ACROSS THE EASTERN MTS. INVERTED V SOUNDINGS PERSIST WITH CONVECTION
REMAINING GENERALLY HIGH BASED...PRODUCING MORE WIND AND VIRGA THAN
MEASURABLE RAINFALL. H7 TEMPS WARM TO BETWEEN 8C AND 12C WILL ALLOW
FOR HIGHS TO BE AT OR SLIGHTLY ABOVE SEASONAL AVERAGES...WITH MAINLY
50S AND 60S ACROSS THE HIGHER TERRAIN AND 70S TO LOWER 80S ACROSS
THE PLAINS WHERE EAST TO SOUTHEAST LOW LEVEL UPSLOPE FLOW WILL
DEVELOP THROUGH THE AFTERNOON.

LATEST MODELS INDICATING A WEAK SHORT WAVE EMBEDDED WITHIN THE
SOUTHWEST FLOW ALOFT MOVING INTO THE AREA THIS EVENING WHICH COULD
KEEP A FEW SHOWERS ACROSS THE HIGHER TERRAIN TONIGHT. HOWEVER...MAIN
EFFECT OF THIS WAVE WILL BE STRENGTHENING LEE TROUGHING ACROSS THE
I-25 CORRIDOR TONIGHT. THIS LEADS TO LOW LEVEL MOISTURE ADVECTING INTO
EASTERN COLORADO WITH ENHANCED EAST TO SOUTHEAST LOW LEVEL UPSLOPE
FLOW. SOUNDINGS INDICATING STRATUS RAPIDLY DEVELOPING AFTER MIDNIGHT
WITH PATCHY FOG POSSIBLE...ESPECIALLY ACROSS EL PASO COUNTY EARLY
THURSDAY MORNING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 430 AM MDT WED MAY 22 2013

MOIST EASTERLY UPSLOPE FLOW WILL CONTINUE OVER THE EASTERN
MOUNTAINS AND PLAINS THURSDAY...LEADING TO MOSTLY CLOUDY SKIES AND
COOL TEMPERATURES...ESPECIALLY EAST OF I-25 WHERE CLOUDS WILL HOLD
ON THE LONGEST. INSTABILITY IS RATHER LIMITED THURSDAY
AFTERNOON...THOUGH WITH LIFTED INDICES FALLING SLIGHTLY BELOW
ZERO...TOUGH TO RULE OUT A BRIEF -SHRA/WEAK -TSRA OVER THE EASTERN
HALF OF THE AREA THROUGH THU EVENING. BEST BET FOR A TSRA THU WILL
LIKELY BE OVER THE EASTERN MOUNTAIN SLOPES...WHERE SOME CLEARING
BY LATE AFTERNOON MAY LEAD TO SLIGHTLY DEEPER INSTABILITY. WESTERN
MOUNTAINS AND VALLEYS WILL REMAIN WARM AND CONVECTION FREE
THURSDAY...AS LOW AND MID LEVELS REMAIN VERY DRY. SOUTHWEST
WINDS MIXING TO THE SURFACE OVER THE SAN LUIS VALLEY WILL LEAD TO
CRITICAL FIRE WEATHER CONDITIONS THU AFTERNOON...SO KEPT FIRE
WEATHER WATCH IN PLACE THU AFTERNOON/EVENING.

UPPER RIDGE AXIS CONTINUES TO SHIFT EAST OF COLORADO FRI INTO THE
WEEKEND...WHICH WILL ALLOW SOUTHWEST FLOW TO GRADUALLY STRENGTHEN
OVER THE AREA THROUGH THE PERIOD. DRYLINE DEVELOPS FRIDAY OVER THE
EASTERN PLAINS...AND APPEARS TO STAY WEST OF THE CO/KS BORDER
THROUGH FRI EVENING. FAIRLY HEALTHY CAPE (1-2K J/KG) DEVELOPS
ALONG AND EAST OF AN EADS/LA JUNTA/TRINIDAD LINE FRI
AFTERNOON...AND WITH 0-6KM SHEAR IN THE 35-45 KNOT RANGE SOME
POTENTIAL FOR SEVERE STORMS OVER THE EAST INTO THE
EVENING...THOUGH CONFIDENCE IS TOO LOW TO MENTION SEVERE IN ANY
FORECASTS YET. FARTHER WEST...MOUNTAINS AND I-25 CORRIDOR LOOK TOO
DRY FOR ANY CONVECTION...AND WITH TEMPERATURES AND WINDS
INCREASING...SUSPECT WE`LL SEE NEAR CRITICAL FIRE WEATHER
CONDITIONS OVER MUCH OF THE AREA BY AFTERNOON. FOR SAT INTO
SUN...SOUTHWEST FLOW ALOFT AND AT THE SURFACE SHUNTS DEEPER
MOISTURE EASTWARD TOWARD KS...THOUGH JUST ENOUGH INSTABILITY
LINGERS NEAR THE KS BORDER TO WARRANT SOME ISOLATED POPS OVER THE
FAR EAST BOTH DAYS. MOUNTAINS AND I-25 CORRIDOR WILL REMAIN WARM
AND DRY WITH FIRE WEATHER CONCERNS PERSISTING. IN FACT...NOT MUCH
CHANGE IN THE PATTERN UNTIL MID-WEEK...WHEN PIECES OF THE WESTERN
U.S. UPPER TROUGH FINALLY BEGIN TO EJECT EASTWARD...POTENTIALLY
BRINGING SLIGHTLY COOLER TEMPERATURES AND A MINOR INCREASE IN
CONVECTION TO THE MOUNTAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1144 AM MDT WED MAY 22 2013

GENERALLY VFR ACROSS FLIGHT AREA UNTIL AROUND 06Z...INCLUDING ALL 3
TAF SITES. HOWEVER...ISOLATED THUNDERSTORMS WILL BE POSSIBLE OVER
AND NEAR THE MOUNTAINS UNTIL THEN...WITH LOCAL MVFR TO LIFR
CONDITIONS ASSOCIATED WITH THAT ACTIVITY. ALSO...ERRATIC WIND
GUSTS TO AROUND 45 MPH POSSIBLE WITH THAT ACTIVITY. STARTING
AROUND 06Z...A SHALLOW COLD FRONT WILL PUSH IN FROM THE EAST AND
BANK UP AGAINST THE SOUTHERN FRONT RANGE.  THIS FRONT WILL BRING
WIDESPREAD MVFR STRATUS TO THE EASTERN PLAINS AND THE POSSIBILITY
OF SOME SCATTERED LIGHT PRECIP THROUGH THE REST OF THE NIGHT AND
INTO THURSDAY. COULD EVEN BE SOME IFR CONDITIONS ACROSS THE PLAINS
ASSOCIATED WITH THE STRATUS LAYER. MVFR TO IFR CONDITIONS ASSOCIATED
WITH STRATUS LAYER TONIGHT WILL AFFECT KCOS AND KPUB BUT NOT KALS. LW

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY
EVENING FOR COZ224.

&&

$$

SHORT TERM...MW
LONG TERM...PETERSEN
AVIATION...LW