000
FXUS65 KPUB 170511
AFDPUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO CO
1111 PM MDT WED APR 16 2014

.UPDATE...
ISSUED AT 849 PM MDT WED APR 16 2014

UPDATED LATEST TEMPS AND MADE MINOR CHANGES TO TEMPS OVERNIGHT.
ADJUSTED SOME SNOWFALL AMOUNTS FOR THE REST OF TONIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 254 PM MDT WED APR 16 2014

...HEAVY WET SNOW FOR THE SOUTHEASTERN MOUNTAINS TONIGHT...

RAPIDLY EVOLVING STORM SYSTEM NOW IS MOVING INTO WRN CO THIS
AFTERNOON. ALREADY AM SEEING SOME BANDED PRECIP...IN THE FORM OF
SHRA...DEVELOP OVER EL PASO COUNTY. DEWPOINTS STILL PRETTY LOW OVER
THE PLAINS...WHICH WILL HELP COOL THINGS OFF THIS EVE AS WET BULB
IS REACHED IN HEAVIER PRECIP. EXPECT PRECIP TO EXPAND AND INTENSIFY
THROUGH THE AFTERNOON...REACHING ITS PEAK FROM 00Z THROUGH 06Z
TONIGHT.

A COUPLE OF RECENT TRENDS ARE MAKING FOR A RATHER TRICKY FORECAST
FOR THE SHORT TERM. RECENT GUIDANCE IS CONSIDERABLY WARMER THAN IT
HAD BEEN A COUPLE DAYS AGO...WITH H7 TEMPS ONLY FALLING TO MINUS
5 OR 6 AS OPPOSED TO THE MINUS 10 OR LOWER FROM EARLIER MODEL RUNS.
THIS IS POINTING AT THE SNOW LEVELS GENERALLY STAYING AT OR
ABOVE 6000 FEET TONIGHT. BUT DEPENDING ON EVENTUAL STRENGTH AND
TIMING...WOULD NOT BE SURPRISED TO SEE SNOW FALLING AT THE LOWER
ELEVATIONS. JUST NOT EXPECTING MUCH IF ANY ACCUMULATION BELOW 6K
FEET...EXCEPT MAYBE ON GRASSY SURFACES. THE WINTER WX ADVISORY FOR
THE SRN I-25 CORRIDOR WILL BE A PARTICULAR CHALLENGE SINCE
ELEVATIONS FROM WALSENBURG TO TRINIDAD ARE GENERALLY IN THE 6000-
6500 FOOT RANGE. SO...EVEN A SLIGHT SHIFT IN THE LOW LEVEL
TEMPERATURES THIS EVE COULD MAKE THE DIFFERENCE BETWEEN WET PAVEMENT
AND A FEW INCHES OF SLUSH. HAVE GENERALLY PLAYED THE MIDDLE ROAD OF
MODEL CONSENSUS...WHICH HAS SNOW LEVELS AT OR ABOVE THAT ELEVATION
FOR THE EARLY EVE. BUT...HIGHER TRRN TO THE WEST AND CLOSER TO
SPANISH PEAKS COULD SEE SIGNIFICANT WET SNOW...MORE THAN SIX INCHES
FOR SOME AREAS.

OTHER ISSUE IS THE RECENT TREND TOWARDS THE HEAVIEST ACCUMS FALLING
OVER THE SRN ZONES...THE WETS AND SRN SANGRES GENERALLY SOUTH OF
HIGHWAY 50. THE HRRR AND LOCAL HI-RES WRF...FOR EXAMPLE...KEEP
MOST OF THE HEAVY PRECIP SOUTH OF THE PIKES PK REGION. THE NAM
AND RUC..LOWER RES...KEEP HEAVY PRECIP OVER THE PIKES PEAK REGION.
GIVEN THE POOR PERFORMANCE OF THE HIGHER RES SOLUTIONS SO FAR...AM
INCLINED TO KEEP WITH AT LEAST MODERATE ACCUMS FOR PIKES
PEAK...ALTHOUGH IT SEEMS REASONABLE THAT SRN AND ERN SIDES WILL GET
A BIT MORE THIS EVE. MODELS ARE HITTING THE SRN SANGRES AND HIGHER
WETS PRETTY HARD THROUGH 06-08Z TONIGHT. HAVE CONSIDERED UPGRADING
FOR THOSE ZONES...BUT SINCE THE LIQUID-SNOW RATIOS WILL BE HIGHER
GIVEN THE WARMER LOW-LEVEL THERMAL PROFILE...EXPECT THE MORE
SIGNIFICANT ACCUMS TO BE PRETTY HIGH UP AND SPOTTY. SO...ADVISORIES
LOOK GOOD FOR NOW BUT WILL HAVE TO FOLLOW THE SHORT TERM TRENDS
PRETTY CAREFULLY.

WILL SEE THE SYSTEM CLEAR OUT GRADUALLY FROM N TO S AFTER MIDNIGHT.
COULD EVEN SEE SOME CLEARING BY SUNRISE ON THURSDAY. BALANCE OF
THURSDAY LOOKS PRETTY NICE...WITH TEMPS REBOUNDING TO THE UPPER 50S
OVER THE PLAINS BY AFTERNOON...AND INCREASING AMOUNTS OF SUN. ROSE

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 254 PM MDT WED APR 16 2014

NEXT SYSTEM WILL BE MOVING INTO THE REGION OVER THE WEEKEND BRINGING
A RETURN OF ACTIVE WEATHER IN THE EXTENDED.  CLOSED LOW MOVES IN
FROM THE PACIFIC...ACROSS SOUTHERN CA AND INTO THE DESERT SOUTHWEST
THROUGH FRIDAY NIGHT.  MOISTURE INCREASES...PARTICULARLY ACROSS
WESTERN AREAS ON FRIDAY...SO SHOULD SEE ISOLATED TO SCATTERED RAIN
AND HIGHER ELEVATION SNOW SHOWERS OVER THE MOUNTAINS WITH SOME
ISOLATED EMBEDDED THUNDERSTORMS POSSIBLE DURING THE AFTERNOON. ANY
SNOWFALL ACCUMULATIONS LOOKS LIGHT THROUGH THIS PERIOD...AND
CONFINED TO THE HIGHER ELEVATIONS.

THIS SYSTEM WILL GRADUALLY FILL AS IT MOVES INTO THE FOUR CORNERS
REGION ON SATURDAY THEN ACROSS CO THROUGH SUNDAY MORNING AS AN OPEN
TROF. PRECIPITATION WILL INCREASE ACROSS THE SOUTHWEST MOUNTAINS
FRIDAY NIGHT...THEN SPREAD ACROSS ALL OF THE MOUNTAINS AND ADJACENT
PLAINS ON SATURDAY.  WITH COOLING ALOFT...LAPSE RATES STEEPEN...AND
A COLD FRONT...THOUGH IT IS NOT ALL THAT COOL BEHIND IT...WILL MOVE
THROUGH THE SOUTHEAST PLAINS DURING THE AFTERNOON.  NAM12 IS THE
FARTHEST SOUTH WITH THE FRONT SAT AFTERNOON SHOWING EASTERLY WINDS
ACROSS THE PLAINS AND DEW POINTS INCREASING INTO THE 40S TO AROUND
50 NEAR THE EASTERN BORDER BY 00Z.  GFS IS A TAD SLOWER...WITH
NORTHERLY WINDS DROPPING THROUGH THE I-25 CORRIDOR DURING THE
AFTERNOON...AND DEW POINTS IN THE 30S THROUGH THE AFTERNOON.  ECMWF
IS FAIRLY SIMILAR TO THE GFS...THOUGH A JUST A TAD MOISTER.  EITHER
WAY...SNOW LEVELS WILL BE ON THE HIGH SIDE AGAIN...PROBABLY AROUND
9.5-10KFT...SO BELOW THIS ELEVATION WILL HAVE TO MONITOR THE BURN
SCARS CLOSELY FOR RAINFALL...ESPECIALLY THE WALDO.  FOR NOW
THOUGH...THINK THAT GFS PROBABLY HAS THE BEST HANDLE...AND ANY
LOCALLY HEAVIER PRECIPITATION AMOUNTS WILL BE SPOTTY AS MODEL CAPE
VALUES ARE NOT ALL THAT HIGH. ISOLATED THUNDERSTORMS WILL ALSO
SPREAD ACROSS THE SOUTHEAST PLAINS SATURDAY AFTERNOON AND
EVENING...THOUGH RAINFALL AMOUNTS LOOK FAIRLY LIGHT AT THIS POINT
AS HIGHER CAPE REMAINS WELL TO THE EAST.

THIS SYSTEM SLOWLY EXITS EASTERN CO ON SUNDAY...SO AFTER
PRECIPITATION WINDS DOWN OVERNIGHT...ENOUGH INSTABILITY AND RESIDUAL
MOISTURE WILL BE PRESENT FOR ANOTHER ROUND OF ISOLATED THUNDERSTORMS
SUNDAY AFTERNOON. THESE LOOK A LITTLE SPOTTIER IN COVERAGE.

DRY WEATHER RETURNS FOR EARLY NEXT WEEK...THEN THE FORECAST WILL
REVOLVE AROUND TRACK OF THE NEXT UPPER LOW WHICH DROPS INTO THE
GREAT BASIN...THEN EVENTUALLY LIFTS OUT TO THE NORTH OF THE FORECAST
AREA WED. THIS WILL PUT MOST OF SOUTH CENTRAL AND SOUTHEAST COLORADO
UNDER STRONG SOUTHWEST FLOW ALOFT WITH THE POTENTIAL FOR CRITICAL
FIRE WEATHER CONDITIONS DEVELOPING ESPECIALLY BY WEDNESDAY.
DEPENDING ON THE CONDITIONS OF FUELS...MAY NEED SOME FIRE WEATHER
HIGHLIGHTS FOR THIS DAY.  OTHERWISE...DRY LINE WILL BE LURKING NEAR
THE CO/KS BORDER DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
TRENDS IN THE LATEST OPERATIONAL GFS AND ECMWF...SEEM TO SUGGEST
A MORE NORTHERN TRACK AND LESS OF A PERSISTENT MERIDIONAL FLOW
EARLY NEXT WEEK...SO THESE LATEST RUNS KEEP THE DRYLINE JUST TO
OUR EAST. HOWEVER...THERE ARE STILL SOME RATHER LARGE DIFFERENCES
IN THE EXTENDED MODELS FOR WED AS GFS SHOWS MORE ENERGY DROPPING
SOUTHWARD INTO THE BASE OF THE TROF ACROSS THE GREAT BASIN WHICH
EC DOES NOT HAVE...SO JURY IS STILL OUT. EITHER WAY...SHOULD BE AN
ACTIVE PERIOD THROUGH NEXT WEEK. -KT

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1107 PM MDT WED APR 16 2014

KALS...SNOW WILL CONTINUE THROUGH 08-10Z TONIGHT WITH REDUCED VIS
AND CIGS TO MVFR TO IFR. AN ADDITIONAL INCH OF SNOW IS POSSIBLE ON
AREA RUNWAYS. EXPECT IMPROVING CONDITIONS BY THURSDAY MORNING WITH
VFR CONDITIONS THROUGH THURSDAY EVENING.

KCOS...A RAIN AND SNOW MIX WILL CONTINUE THROUGH 10-12Z TONIGHT
WITH REDUCED CIGS AND VIS TO MVFR. EXPECT IMPROVING CONDITIONS
AFTER 12Z WITH VFR CONDITIONS THROUGH THURSDAY EVENING.

KPUB...LIGHT RAIN WILL CONTINUE...AND PERHAPS MIX WITH SNOW
THROUGH AROUND 12Z WITH REDUCED CIGS TO NEAR MVFR. EXPECT RAIN AND
SNOW TO DISSIPATE BY THURSDAY MORNING WITH VFR CONDITIONS EXPECTED
THROUGH THURSDAY AFTERNOON.  MOZLEY

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 AM MDT THURSDAY FOR COZ072>075-
079>082-087-088.

&&

$$

UPDATE...28
SHORT TERM...ROSE
LONG TERM...KT
AVIATION...MOZLEY