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000
FXUS65 KRIW 311739
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1139 AM MDT FRI OCT 31 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

THE HIGH PRESSURE RIDGE OVERHEAD WILL SLIDE OFF TO THE EAST TODAY
ALLOWING THE STEERING FLOW TO BACK MORE TO THE SOUTHWEST USHERING
IN WARMER AIR WITH MANY LOWER ELEVATIONS EAST OF THE DIVIDE
REACHING HIGH TEMPERATURES IN THE 70S TODAY AND IN THE 60S WEST.
THE EASTERN CWA WILL EKE OUT ANOTHER NICE DAY BEFORE CLOUDS
INCREASE AHEAD OF THE NEXT WEATHER SYSTEM. THE CIRCULATION NOW OFF
THE PACIFIC COAST OUT AT 45N/135W IS DRAWING SUBTROPICAL PACIFIC
MOISTURE NORTH INTO THE PAC NW OUT AHEAD OF IT WITH LIGHTNING
BREAKING OUT OVER OREGON WITHIN THE LAST FEW HOURS. THE ENERGY
FROM THE ASSOCIATED TROUGH WILL SPLIT BY SATURDAY AS IT ENCOUNTERS
THE RIDGE OVER THE CENTRAL UNITED STATES. THE MODELS SEEM MORE
REALISTIC WITH THIS APPROACH THAN PREVIOUS RUNS THAT DID NOT SHOW
AS MUCH OF A SPLIT. BOTH THE EURO AND THE GFS SHOW THIS SPLIT
TAKING PLACE. WE WILL FOCUS OUR ATTENTION ON THE CLOSER NORTHERN
PIECE OF ENERGY. SOUTHWEST BREEZES WILL INCREASE TODAY FROM RKS TO
CPR AHEAD OF THE APPROACHING PACIFIC WEATHER SYSTEM. THE TROUGH
WILL MAKE LANDFALL BY SATURDAY. AS IT DOES...CLOUDS WILL INCREASE
FROM THE WEST AND SHOWERS ALONG WITH EMBEDDED ISOLATED
THUNDERSTORMS WILL BREAK OUT IN WESTERN WY ALONG AND WEST OF THE
DIVIDE WITH SHOWERS INCREASING DURING THE AFTERNOON HOURS
SATURDAY. ON SATURDAY...A NORTHERN STREAM CIRCULATION WILL CLOSE
OFF OVER NEVADA/OREGON. THIS H5 LOW WILL OPEN BUT REMAIN A FOCUSED
AREA OF VORTICITY AS IT TRACKS ACROSS IDAHO AND INTO MONTANA
SATURDAY NIGHT AND INTO SUNDAY. THE H7 LOW WILL TAKE A SIMILAR
TRACK WITH THE SFC LOW TRACKING NORTHEAST ACROSS NW WY EARLY
SATURDAY EVENING. THIS LOW WILL HAVE A FAIRLY WELL DEFINED WARM
AND COLD FRONT AND A RESULTING WELL DEVELOPED COMMA CLOUD. MOST OF
THE MORE WIDESPREAD DYNAMICS WILL COME TOGETHER SATURDAY NIGHT.
LEFT FRONT QUAD DYNAMICS WILL ADD TO THE LIFT SATURDAY NIGHT AS
THE JET SHIFTS TO OUR SOUTH. AS THIS TROUGH NEARS...SOUTHWEST
WINDS WILL CONTINUE TO INCREASE FROM RKS TO CPR SATURDAY. WHEN THE
ASCT COLD FRONT TRAILING FROM THE PACIFIC SURFACE LOW...MANY OTHER
AREAS WILL SEE AN INCREASE IN WIND SPEED AS THE WINDS VEER
SATURDAY EVENING WITH SOME AREAS SEEING AN 8MB 3 HOURLY SFC
PRESSURE RISE. SNOW LEVELS WILL DROP TO THE VALLEY FLOORS SATURDAY
NIGHT OUT WEST. AS THE PACIFIC SYSTEM MOVES NORTHEAST INTO
MONTANA...SHOWERS WILL BECOME MORE PREVALENT IN NORTHERN WY AND
WILL CONTINUE IN WESTERN WY SUNDAY FROM THE LIFT MORE DIRECTLY
ASSOCIATED WITH THE LOW. THE HEAVIEST MOST WIDESPREAD PRECIP
SHOULD REMAIN NORTH OF THE AREA SUNDAY IN MT WHERE THE BEST WRAP
AROUND IS ENTROPIC LIFT WILL BE LOCATED. AS THIS WEATHER SYSTEM
CONTINUES TO PULL AWAY FROM US TO THE NORTHEAST SUNDAY NIGHT THE
SHOWERS WILL DIMINISH. AFTER ALL IS SAID AND DONE...2 TO 4 INCHES
OF SNOWFALL IS EXPECTED IN THE WESTERN VALLEYS BY LATE SUNDAY AND
4 TO 8 INCHES IN THE SURROUNDING MOUNTAINS. ONLY 1 TO 3 INCHES ARE
EXPECTED IN THE BIG HORN MOUNTAINS BY SUNDAY NIGHT. AS FAR AS ANY
POTENTIAL SIGNIFICANT SNOW BANDING GOES EAST OF THE DIVIDE...IT
NOW APPEARS THAT THE POST FRONTAL H7 NORTHWEST FLOW WILL BE TOO
WEAK TO SUPPORT ANY WITH THE MAIN ENERGY TO DRIVE THESE TYPE OF
SNOW SHOWERS TO FAR NORTH,

.LONG TERM...MONDAY THROUGH FRIDAY

WEAK BUT CHILLY NW FLOW STARTS THE PERIOD AS THE WEEKEND TROUGH
LINGERS OVER THE AREA THROUGH THE DAY BUT WITH MOST OF THE ENERGY
SPLIT BETWEEN A LOW NEAR FAR NRN ND AND ANOTHER OVER THE DESERT SW.
JUST SOME CHILLY AIR LEFT BEHIND WITH MAYBE A LITTLE RESIDUAL
MOISTURE IN THE MTNS AND SE FRINGES TO START THE PERIOD. MONDAY
SHOULD BE THE COLDEST DAY AND MONDAY NIGHT THE COLDEST NIGHT BEFORE
WE BEGIN ANOTHER WARMING TREND THROUGH THURSDAY. UPPER LOW AND COLD
AIR BETWEEN ALASKA AND THE ALEUTIAN CHAIN WORK TOGETHER TO DEVELOP
ANOTHER TROUGH OVER THE ERN PACIFIC EARLY NEXT WEEK THAT PUMPS UP
THE RIDGE OVER THE WEST. HEIGHTS RISE THROUGH AT LEAST WEDNESDAY
NIGHT AND MID LEVEL TEMPERATURES PEAK ON THURSDAY. HIGHS GENERALLY
START OUT MONDAY IN THE 40S WITH MAINLY 30S IN THE MOUNTAINS AND
THEN WARM ON AVERAGE 5 TO 8 DEGREES EACH DAY THROUGH THURSDAY. IF WE
GET ENOUGH MIXING...THURSDAY COULD BE EVEN WARMER WITH BOTH THE GFS
AND ECMWF SHOWING H7 TEMPERATURES BETWEEN +6 TO +10 EAST OF THE
DIVIDE. A SHORTWAVE THEN ROTATES THROUGH THE ERN PACIFIC TROUGH AND
THE RIDGE MAY WEAKEN ENOUGH TO BRING A CHANCE OF RAIN/SNOW ACROSS
THE AREA ON FRIDAY. FOR NOW...MAINLY CONFINING POPS TO THE MTNS OF
THE WEST AND NORTH WITH A SLIGHT CHANCE IN THE LOWER ELEVATIONS OF
THE NORTH. NOT A LOT OF PCPN POTENTIAL THROUGH THE WEEK BUT THERE
MAY BE JUST ENOUGH FLOW AND WEAK DISTURBANCES/MOISTURE IN THE NW
FLOW TO ALLOW SOME VERY LIGHT MTN SHOWERS/SPRINKLES/FLURRIES AT
TIMES IN THE NW MTNS TUESDAY AND WEDNESDAY. AN INCREASE IN WINDS AT
TIMES IN THE MOUNTAINS AND NORMALLY WINDY AREAS WITH EACH PASSING
RIPPLE BUT NOTHING TOO SIGNIFICANT EXPECTED. WE DO GET A LITTLE
BETTER GRADIENT ON THE GFS BY THURSDAY AND IF THIS DOES OCCUR THEN
LIKE MENTIONED ABOVE TEMPERATURES COULD SOAR EAST OF THE DIVIDE TO
RECORD TERRITORY. TOO EARLY YET TO GO THAT WARM BUT JUST SOMETHING
TO WATCH OVER THE NEXT SEVERAL DAYS.

.AVIATION.../18Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

THE AIRPORTS WILL HAVE PREVAILING VFR CONDITIONS THROUGH 18Z SATURDAY.
SOUTHWEST FLOW ALOFT WILL INCREASE WITH INCREASING MID AND UPPER LEVEL
CLOUDS WITH AREAS OF MVFR CEILINGS AND VISIBILITIES DEVELOPING ALONG
AND EAST OF THE CONTINENTAL DIVIDE ABOVE 9000 FEET WITH MAINLY
SNOW SHOWERS MOVING IN.  OVER AND NEAR THE EAST SLOPES OF THE MOUNTAINS
STRONG DOWNSLOPE WINDS WILL DEVELOP WITH AREAS OF LOW LEVEL WIND SHEAR.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

THE AIRPORTS WILL HAVE PREVAILING VFR CONDITIONS THROUGH 10Z
SATURDAY. SOUTHWEST FLOW ALOFT WILL INCREASE WITH INCREASING MID
AND UPPER LEVEL CLOUDS WITH AREAS OF MVFR CEILINGS AND VISIBILITIES
DEVELOPING OVER THE WESTERN MOUNTAINS AND VALLEYS 8000 FEET WITH
MAINLY SNOW SHOWERS MOVING IN. OVER THE MOUNTAINS STRONG RIDGE TOP
WINDS WILL DEVELOP WITH AREAS OF LOW LEVEL WIND SHEAR.

.FIRE WEATHER...

A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TODAY FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES. THE NEXT POTENTIAL ROUND OF PRECIPITATION MAY
BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA OF LOW PRESSURE
APPROACHES WESTERN WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...C.BAKER
FIRE WEATHER...LIPSON








000
FXUS65 KRIW 310910
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
310 AM MDT FRI OCT 31 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
THE HIGH PRESSURE RIDGE OVERHEAD WILL SLIDE OFF TO THE EAST TODAY
ALLOWING THE STEERING FLOW TO BACK MORE TO THE SOUTHWEST USHERING IN
WARMER AIR WITH MANY LOWER ELEVATIONS EAST OF THE DIVIDE REACHING
HIGH TEMPERATURES IN THE 70S TODAY AND IN THE 60S WEST. THE EASTERN CWA
WILL EKE OUT ANOTHER NICE DAY BEFORE CLOUDS INCREASE AHEAD OF THE
NEXT WEATHER SYSTEM. THE CIRCULATION NOW OFF THE PACIFIC COAST OUT
AT 45N/135W IS DRAWING SUBTROPICAL PACIFIC MOISTURE NORTH INTO THE
PAC NW OUT AHEAD OF IT WITH LIGHTNING BREAKING OUT OVER OREGON
WITHIN THE LAST FEW HOURS. THE ENERGY FROM THE ASSOCIATED TROUGH
WILL SPLIT BY SATURDAY AS IT ENCOUNTERS THE RIDGE OVER THE CENTRAL
UNITED STATES. THE MODELS SEEM MORE REALISTIC WITH THIS APPROACH
THAN PREVIOUS RUNS THAT DID NOT SHOW AS MUCH OF A SPLIT. BOTH THE
EURO AND THE GFS SHOW THIS SPLIT TAKING PLACE. WE WILL FOCUS OUR
ATTENTION ON THE CLOSER NORTHERN PIECE OF ENERGY. SOUTHWEST BREEZES
WILL INCREASE TODAY FROM RKS TO CPR AHEAD OF THE APPROACHING PACIFIC
WEATHER SYSTEM. THE TROUGH WILL MAKE LANDFALL BY SATURDAY. AS IT
DOES...CLOUDS WILL INCREASE FROM THE WEST AND SHOWERS ALONG WITH
EMBEDDED ISOLATED THUNDERSTORMS WILL BREAK OUT IN WESTERN WY ALONG
AND WEST OF THE DIVIDE WITH SHOWERS INCREASING DURING THE AFTERNOON
HOURS SATURDAY. ON SATURDAY...A NORTHERN STREAM CIRCULATION WILL CLOSE OFF
OVER NEVADA/OREGON. THIS H5 LOW WILL OPEN BUT REMAIN A FOCUSED AREA
OF VORTICITY AS IT TRACKS ACROSS IDAHO AND INTO MONTANA SATURDAY
NIGHT AND INTO SUNDAY. THE H7 LOW WILL TAKE A SIMILAR TRACK WITH THE
SFC LOW TRACKING NORTHEAST ACROSS NW WY EARLY SATURDAY EVENING. THIS
LOW WILL HAVE A FAIRLY WELL DEFINED WARM AND COLD FRONT AND A
RESULTING WELL DEVELOPED COMMA CLOUD. MOST OF THE MORE WIDESPREAD
DYNAMICS WILL COME TOGETHER SATURDAY NIGHT. LEFT FRONT QUAD DYNAMICS
WILL ADD TO THE LIFT SATURDAY NIGHT AS THE JET SHIFTS TO OUR SOUTH.
AS THIS TROUGH NEARS...SOUTHWEST WINDS WILL CONTINUE TO INCREASE
FROM RKS TO CPR SATURDAY. WHEN THE ASCT COLD FRONT TRAILING FROM THE PACIFIC
SURFACE LOW...MANY OTHER AREAS WILL SEE AN INCREASE IN WIND SPEED AS
THE WINDS VEER SATURDAY EVENING WITH SOME AREAS SEEING AN 8MB 3
HOURLY SFC PRESSURE RISE. SNOW LEVELS WILL DROP TO THE VALLEY FLOORS
SATURDAY NIGHT OUT WEST. AS THE PACIFIC SYSTEM MOVES NORTHEAST INTO
MONTANA...SHOWERS WILL BECOME MORE PREVALENT IN NORTHERN WY AND WILL
CONTINUE IN WESTERN WY SUNDAY FROM THE LIFT MORE DIRECTLY
ASSOCIATED WITH THE LOW. THE HEAVIEST MOST WIDESPREAD PRECIP SHOULD
REMAIN NORTH OF THE AREA SUNDAY IN MT WHERE THE BEST WRAP AROUND
IS ENTROPIC LIFT WILL BE LOCATED. AS THIS WEATHER SYSTEM CONTINUES TO
PULL AWAY FROM US TO THE NORTHEAST SUNDAY NIGHT THE SHOWERS WILL
DIMINISH. AFTER ALL IS SAID AND DONE...2 TO 4 INCHES OF SNOWFALL IS
EXPECTED IN THE WESTERN VALLEYS BY LATE SUNDAY AND 4 TO 8 INCHES IN
THE SURROUNDING MOUNTAINS. ONLY 1 TO 3 INCHES ARE EXPECTED IN THE
BIG HORN MOUNTAINS BY SUNDAY NIGHT. AS FAR AS ANY POTENTIAL
SIGNIFICANT SNOW BANDING GOES EAST OF THE DIVIDE...IT NOW APPEARS
THAT THE POST FRONTAL H7 NORTHWEST FLOW WILL BE TOO WEAK TO
SUPPORT ANY WITH THE MAIN ENERGY TO DRIVE THESE TYPE OF SNOW
SHOWERS TO FAR NORTH,

.LONG TERM...MONDAY THROUGH FRIDAY

WEAK BUT CHILLY NW FLOW STARTS THE PERIOD AS THE WEEKEND TROUGH
LINGERS OVER THE AREA THROUGH THE DAY BUT WITH MOST OF THE ENERGY
SPLIT BETWEEN A LOW NEAR FAR NRN ND AND ANOTHER OVER THE DESERT SW.
JUST SOME CHILLY AIR LEFT BEHIND WITH MAYBE A LITTLE RESIDUAL
MOISTURE IN THE MTNS AND SE FRINGES TO START THE PERIOD. MONDAY
SHOULD BE THE COLDEST DAY AND MONDAY NIGHT THE COLDEST NIGHT BEFORE
WE BEGIN ANOTHER WARMING TREND THROUGH THURSDAY. UPPER LOW AND COLD
AIR BETWEEN ALASKA AND THE ALEUTIAN CHAIN WORK TOGETHER TO DEVELOP
ANOTHER TROUGH OVER THE ERN PACIFIC EARLY NEXT WEEK THAT PUMPS UP
THE RIDGE OVER THE WEST. HEIGHTS RISE THROUGH AT LEAST WEDNESDAY
NIGHT AND MID LEVEL TEMPERATURES PEAK ON THURSDAY. HIGHS GENERALLY
START OUT MONDAY IN THE 40S WITH MAINLY 30S IN THE MOUNTAINS AND
THEN WARM ON AVERAGE 5 TO 8 DEGREES EACH DAY THROUGH THURSDAY. IF WE
GET ENOUGH MIXING...THURSDAY COULD BE EVEN WARMER WITH BOTH THE GFS
AND ECMWF SHOWING H7 TEMPERATURES BETWEEN +6 TO +10 EAST OF THE
DIVIDE. A SHORTWAVE THEN ROTATES THROUGH THE ERN PACIFIC TROUGH AND
THE RIDGE MAY WEAKEN ENOUGH TO BRING A CHANCE OF RAIN/SNOW ACROSS
THE AREA ON FRIDAY. FOR NOW...MAINLY CONFINING POPS TO THE MTNS OF
THE WEST AND NORTH WITH A SLIGHT CHANCE IN THE LOWER ELEVATIONS OF
THE NORTH. NOT A LOT OF PCPN POTENTIAL THROUGH THE WEEK BUT THERE
MAY BE JUST ENOUGH FLOW AND WEAK DISTURBANCES/MOISTURE IN THE NW
FLOW TO ALLOW SOME VERY LIGHT MTN SHOWERS/SPRINKLES/FLURRIES AT
TIMES IN THE NW MTNS TUESDAY AND WEDNESDAY. AN INCREASE IN WINDS AT
TIMES IN THE MOUNTAINS AND NORMALLY WINDY AREAS WITH EACH PASSING
RIPPLE BUT NOTHING TOO SIGNIFICANT EXPECTED. WE DO GET A LITTLE
BETTER GRADIENT ON THE GFS BY THURSDAY AND IF THIS DOES OCCUR THEN
LIKE MENTIONED ABOVE TEMPERATURES COULD SOAR EAST OF THE DIVIDE TO
RECORD TERRITORY. TOO EARLY YET TO GO THAT WARM BUT JUST SOMETHING
TO WATCH OVER THE NEXT SEVERAL DAYS.

&&

.AVIATION.../12Z ISSUANCE/
VFR CONDITIONS WILL OCCUR THROUGH 12Z SATURDAY. EXPECT SOME
AFTERNOON WIND AT KCPR AND KRKS TERMINAL SITES.

&&

.FIRE WEATHER...
A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TODAY FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES. THE NEXT POTENTIAL ROUND OF PRECIPITATION MAY
BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA OF LOW PRESSURE
APPROACHES WESTERN WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...AR
FIRE WEATHER...LIPSON











000
FXUS65 KRIW 310524
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1124 PM MDT THU OCT 30 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT (ISSUED AT 310 PM MDT)

A FAIRLY UNEVENTFUL FORECAST THROUGH THE SHORT TERM. SATELLITE
IMAGERY DOES SHOW SOME MID TO HIGH LEVEL CLOUDS MOVING OVER THE TOP
OF THE RIDGE SO SOME AREAS...ESPECIALLY IN THE NORTHERN AND EASTERN
PORTIONS OF THE COUNTY WARNING AREA WILL SEE A BROKEN DECK OF CLOUDS
BUT NO PRECIPITATION IS EXPECTED. THIS PATTERN IS EXPECTED TO
CONTINUE THROUGH TONIGHT AS WELL AND INTO TOMORROW. AS A RESULT...WE
HAVE INCREASED SKY COVER A BIT IN THOSE AREAS BUT ONLY TO PARTLY
CLOUDY FOR MOST AREAS. THE OTHER CONCERN WILL BE FOR INCREASE IN THE
BREEZE LATE TONIGHT AND ESPECIALLY TOMORROW AS A SYSTEM APPROACHES
FROM THE WEST. THIS WILL TIGHTEN THE PRESSURE GRADIENT A BIT AND
BRING A GUSTY SOUTHWESTERLY BREEZE...ESPECIALLY ACROSS THE FAVORED
AREAS LIKE FROM ROCK SPRINGS TO CASPER. HOWEVER...700 MILLIBAR WINDS
TOP OUT AT ONLY 35 KNOTS SO IT LOOKS ONLY BREEZY...NOT WINDY AND ANY
HIGH WIND HIGHLIGHTS ALMOST CERTAINLY WILL NOT BE NEEDED.
TEMPERATURES WILL CONTINUE TO BE WELL ABOVE NORMAL WITH HIGHS
POSSIBLY REACHING THE 70S IN SOME WARMER BASIN LOCATIONS ALTHOUGH IF
CLOUDS ARE A BIT MORE WIDESPREAD THIS MAY INHIBIT HEATING JUST A
BIT. AS FOR HALLOWEEN NIGHT AND THE ALL IMPORTANT TRICK OR TREATING
FORECAST...IT LOOKS LIKE A PARTLY TO MOSTLY CLEAR SKY AND
TEMPERATURES GENERALLY IN THE 40S AND 50S DEPENDING ON YOUR
ELEVATION SO THINGS LOOK GOOD FOR THE ANNUAL CANDY GATHERING. LATE
AT NIGHT AFTER THE KIDS HAVE HOPEFULLY GONE TO SLEEP...SOME MOISTURE
ADVECTING FROM THE SOUTH AND WEST COULD BRING A FEW SPRINKLES OR
FLURRIES TO THE HIGHER ELEVATIONS WEST OF THE DIVIDE BUT THESE LOOK
INCONSEQUENTIAL ENOUGH THAT WE LEFT THEM OUT OF THE FORECAST.

.LONG TERM...SATURDAY THROUGH THURSDAY

BEGINNING OF FCST...END OF UPR RIDGING WITH SOUTHWEST FLOW FIRMLY IN
PLACE AHEAD OF WRN CONUS TROF AND FIRST INFLUENCES OF JET STREAK/SW
BEING FELT OVR THE WRN FA. HOWEVER...LOW MOISTURE CONTENT OF THE
ATMOSPHERE AT THIS TIME WILL KEEP QPF ON THE LOW SIDE AT LEAST THRU
THE FIRST 12 HRS OF THE FCST. WEAK CYCLOGENESIS JUST STARTING TO
PROCEED OVR THE GREAT BASIN WITH LEE SIDE TROFFING SETTING EAST OF
THE BIGHORNS. AS SFC P GRAD INCREASES WITH THIS DEVELOPING STORM
SYSTEM...WIND SPEEDS ACROSS THE USUAL WIND CORRIDOR WITH ALSO
INCREASE BY SAT AFTERNOON...WITH GUSTS 45 TO 50 MPH COMMON INTO THE
EVENING PERIOD BEFORE DECREASING OVERNIGHT. THE WIND WILL RETURN
AGAIN BY SUNDAY AFTERNOON.

BY SAT NIGHT...ADDITIONAL CHANGES FROM THE APPROACHING...
INTENSIFYING AND  EVOLVING SYSTEM REALLY START TO COME INTO PLAY AS
SFC/UPR LOW SPINS UP OVR NRN WY/SRN MT...ALONG/NEAR INTERSECTION
WITH LEE TROF. AS CYCLONE SPINS UP...EXPECT VERY STRONG WINDS ALOFT
INVOF LOW SAT NIGHT INTO SUN MORNING AFFECTING THE MOUNTAIN PEAKS
WEST OF BUFFALO FOR A SHORT PERIOD BEFORE THE LOW MOVES OFF TO THE
NNE. ACROSS THE WRN CWA...N/S ORIENTED JET MOVES OVERHEAD...
SUBSTANTIALLY INTENSIFYING PRECIP ASSOCIATED WITH...BY THIS
TIME...INCREASED  MOISTURE. THIS FIRST BURST OF PRECIP...AND RAIN
CHANGING SNOW...WILL MOVE QUICKLY NORTH AND INTO CNTRL MT BY SUN
MORNING. MOUNTAINS SHOULD RECEIVE UP TO 3 INCHES OF WET SNOWFALL
FROM THIS FIRST HIT. THEN...AS THE CYCLONE MATURES RATHER QUICKLY
WITH RAPIDLY DEVELOPING INSTABILITY UNDER COOL UPR TEMPS...AND
DECENT BAROCLINICITY...A LARGE AREA OF PRECIPITATION WILL BREAK OUT
WEST OF THE SFC LOW...WITH GREATEST INTENSITY NEARLY DIRECTLY UNDER
THE H5 TROF AXIS OVR NERN ID/WRN MT. THIS WILL RESULT IN A BIT
LIGHTER BUT MORE PERSISTENT RAINFALL/SNOWFALL ACROSS THE WRN TO NRN
CWA. ANOTHER AREA OF GOOD PRECIP WILL BE CO-LOCATED WITH THE UPR JET
FROM NCNTRL CO THRU SERN WY...WELL OUT OF THE FA. ATTM...IT WOULD
APPEAR THAT THE MOUNTAINS OF SW YELLOWSTONE AND PERHAPS THE TETONS
TO THE SOUTH WILL BE IN THE BEST POSITION FOR GREATEST SNOWFALL
POTENTIAL...WITH MUCH OF THIS REGION RECEIVING 3 TO 6 INCHES IN A 24
HR PERIOD...WITH LOCALIZED PREFERRED AREAS GETTING UP TO 8 INCHES.
PERHAPS ANOTHER INCH OR TWO MAY BE HAD SUNDAY NIGHT INTO MONDAY
MORNING...ALTHOUGH THIS IS MUCH MORE SPECULATION THAN EMPIRICAL
SCIENCE AT THIS POINT. LOWER ELEVATIONS LOOK TO BE THE RECIPIENTS OF
UP TO 3 INCHES OF SNOW OVER THE SAME PERIOD OF TIME. ALL THESE
SNOWFALL NUMBERS PUT THE WRN FA DANGEROUSLY CLOSE TO ADVISORY
CONDITIONS. IF THE LOCATION OF THE UPR AND SFC LOWS HAD PLACED
CYCLOGENESIS FURTHER EWD...OR WAS SLOWER TO DEVELOP AND
EVOLVE...THIS WOULD/COULD HAVE BEEN MUCH WORSE THAN IT WILL BE.
STILL...THE CURRENT DEVELOPMENT OF THIS SYSTEM WARRANTS CONTINUED
MONITORING IN CASE THERE ARE SIGNIFICANT SPATIAL OR TEMPORAL
DIFFERENCES BETWEEN NOW AND THEN THAT MAY CAUSE POTENTIAL SNOWFALL
TO INCREASE. LATER SUNDAY EVENING/OVERNIGHT WILL BE THE ONLY
REALISTIC PERIOD WHERE MOST LOWER ELEVATIONS WILL SEE ANY CHANCE FOR
PRECIP REACHING THE GROUND AS TROF AXIS SWINGS THRU.

BY MON AFTERNOON...MOST TRACES OF THE STORM SYSTEM...BOTH SFC AND
ALOFT...WILL HAVE MOVED E TO SE OF WY...LEAVING BEHIND CLEARING
SKIES AND COLDER TEMPS. SLOW WARMING AND MOSTLY DRY CONDITIONS UNDER
CONTINUING NW FLOW UNTIL UNTIL AT LEAST THURSDAY...WHEN A TRANSITION
TO FLAT RIDGING MAY ENSUE. WINDS LOOK TO INCREASE ACROSS THE USUAL
SPOTS TUE NIGHT INTO WED MORNING. OTHERWISE...OVER THE FINAL THREE
DAYS OF THE FCST...THE ONLY AREA WHICH MAY HAVE SMALL CHCS FOR
PRECIP WILL BE ACROSS THE NW MOUNTAINS UNDER MODEST MID LVL TERRAIN
FORCED CONDITIONS..FAVORING THE UPR WRN SLOPES.

&&

.AVIATION.../06Z ISSUANCE/

VFR CONDITIONS WILL OCCUR THROUGH 06Z SATURDAY. EXPECT SOME
AFTERNOON WIND AT KCPR AND KRKS TERMINAL SITES.

&&

.FIRE WEATHER...

A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TOMORROW FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES ON FRIDAY. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...BRAUN
AVIATION...AR
FIRE WEATHER...HATTINGS








000
FXUS65 KRIW 302110
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
310 PM MDT THU OCT 30 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT

A FAIRLY UNEVENTFUL FORECAST THROUGH THE SHORT TERM. SATELLITE
IMAGERY DOES SHOW SOME MID TO HIGH LEVEL CLOUDS MOVING OVER THE TOP
OF THE RIDGE SO SOME AREAS...ESPECIALLY IN THE NORTHERN AND EASTERN
PORTIONS OF THE COUNTY WARNING AREA WILL SEE A BROKEN DECK OF CLOUDS
BUT NO PRECIPITATION IS EXPECTED. THIS PATTERN IS EXPECTED TO
CONTINUE THROUGH TONIGHT AS WELL AND INTO TOMORROW. AS A RESULT...WE
HAVE INCREASED SKY COVER A BIT IN THOSE AREAS BUT ONLY TO PARTLY
CLOUDY FOR MOST AREAS. THE OTHER CONCERN WILL BE FOR INCREASE IN THE
BREEZE LATE TONIGHT AND ESPECIALLY TOMORROW AS A SYSTEM APPROACHES
FROM THE WEST. THIS WILL TIGHTEN THE PRESSURE GRADIENT A BIT AND
BRING A GUSTY SOUTHWESTERLY BREEZE...ESPECIALLY ACROSS THE FAVORED
AREAS LIKE FROM ROCK SPRINGS TO CASPER. HOWEVER...700 MILLIBAR WINDS
TOP OUT AT ONLY 35 KNOTS SO IT LOOKS ONLY BREEZY...NOT WINDY AND ANY
HIGH WIND HIGHLIGHTS ALMOST CERTAINLY WILL NOT BE NEEDED.
TEMPERATURES WILL CONTINUE TO BE WELL ABOVE NORMAL WITH HIGHS
POSSIBLY REACHING THE 70S IN SOME WARMER BASIN LOCATIONS ALTHOUGH IF
CLOUDS ARE A BIT MORE WIDESPREAD THIS MAY INHIBIT HEATING JUST A
BIT. AS FOR HALLOWEEN NIGHT AND THE ALL IMPORTANT TRICK OR TREATING
FORECAST...IT LOOKS LIKE A PARTLY TO MOSTLY CLEAR SKY AND
TEMPERATURES GENERALLY IN THE 40S AND 50S DEPENDING ON YOUR
ELEVATION SO THINGS LOOK GOOD FOR THE ANNUAL CANDY GATHERING. LATE
AT NIGHT AFTER THE KIDS HAVE HOPEFULLY GONE TO SLEEP...SOME MOISTURE
ADVECTING FROM THE SOUTH AND WEST COULD BRING A FEW SPRINKLES OR
FLURRIES TO THE HIGHER ELEVATIONS WEST OF THE DIVIDE BUT THESE LOOK
INCONSEQUENTIAL ENOUGH THAT WE LEFT THEM OUT OF THE FORECAST.

.LONG TERM...SATURDAY THROUGH THURSDAY

BEGINNING OF FCST...END OF UPR RIDGING WITH SOUTHWEST FLOW FIRMLY IN
PLACE AHEAD OF WRN CONUS TROF AND FIRST INFLUENCES OF JET STREAK/SW
BEING FELT OVR THE WRN FA. HOWEVER...LOW MOISTURE CONTENT OF THE
ATMOSPHERE AT THIS TIME WILL KEEP QPF ON THE LOW SIDE AT LEAST THRU
THE FIRST 12 HRS OF THE FCST. WEAK CYCLOGENESIS JUST STARTING TO
PROCEED OVR THE GREAT BASIN WITH LEE SIDE TROFFING SETTING EAST OF
THE BIGHORNS. AS SFC P GRAD INCREASES WITH THIS DEVELOPING STORM
SYSTEM...WIND SPEEDS ACROSS THE USUAL WIND CORRIDOR WITH ALSO INCREASE BY
SAT AFTERNOON...WITH GUSTS 45 TO 50 MPH COMMON INTO THE EVENING
PERIOD BEFORE DECREASING OVERNIGHT. THE WIND WILL RETURN AGAIN BY
SUNDAY AFTERNOON.

BY SAT NIGHT...ADDITIONAL CHANGES FROM THE
APPROACHING...INTENSIFYING AND EVOLVING SYSTEM REALLY START TO COME
INTO PLAY AS SFC/UPR LOW SPINS UP OVR NRN WY/SRN MT...ALONG/NEAR
INTERSECTION WITH LEE TROF. AS CYCLONE SPINS UP...EXPECT VERY STRONG
WINDS ALOFT INVOF LOW SAT NIGHT INTO SUN MORNING AFFECTING THE
MOUNTAIN PEAKS WEST OF BUFFALO FOR A SHORT PERIOD BEFORE THE LOW
MOVES OFF TO THE NNE. ACROSS THE WRN CWA...N/S ORIENTED JET MOVES
OVERHEAD...SUBSTANTIALLY INTENSIFYING PRECIP ASSOCIATED WITH...BY
THIS TIME...INCREASED  MOISTURE. THIS FIRST BURST OF PRECIP...AND
RAIN CHANGING SNOW...WILL MOVE QUICKLY NORTH AND INTO CNTRL MT BY
SUN MORNING. MOUNTAINS SHOULD RECEIVE UP TO 3 INCHES OF WET SNOWFALL
FROM THIS FIRST HIT. THEN...AS THE CYCLONE MATURES RATHER QUICKLY
WITH RAPIDLY DEVELOPING INSTABILITY UNDER COOL UPR TEMPS...AND
DECENT BAROCLINICITY...A LARGE AREA OF PRECIPITATION WILL BREAK OUT
WEST OF THE SFC LOW...WITH GREATEST INTENSITY NEARLY DIRECTLY UNDER
THE H5 TROF AXIS OVR NERN ID/WRN MT. THIS WILL RESULT IN A BIT
LIGHTER BUT MORE PERSISTENT RAINFALL/SNOWFALL ACROSS THE WRN TO NRN
CWA. ANOTHER AREA OF GOOD PRECIP WILL BE CO-LOCATED WITH THE UPR JET
FROM NCNTRL CO THRU SERN WY...WELL OUT OF THE FA. ATTM...IT WOULD
APPEAR THAT THE MOUNTAINS OF SW YELLOWSTONE AND PERHAPS THE TETONS
TO THE SOUTH WILL BE IN THE BEST POSITION FOR GREATEST SNOWFALL
POTENTIAL...WITH MUCH OF THIS REGION RECEIVING 3 TO 6 INCHES IN A 24
HR PERIOD...WITH LOCALIZED PREFERRED AREAS GETTING UP TO 8 INCHES.
PERHAPS ANOTHER INCH OR TWO MAY BE HAD SUNDAY NIGHT INTO MONDAY
MORNING...ALTHOUGH THIS IS MUCH MORE SPECULATION THAN EMPIRICAL
SCIENCE AT THIS POINT. LOWER ELEVATIONS LOOK TO BE THE RECIPIENTS OF
UP TO 3 INCHES OF SNOW OVER THE SAME PERIOD OF TIME. ALL THESE
SNOWFALL NUMBERS PUT THE WRN FA DANGEROUSLY CLOSE TO ADVISORY
CONDITIONS. IF THE LOCATION OF THE UPR AND SFC LOWS HAD PLACED
CYCLOGENESIS FURTHER EWD...OR WAS SLOWER TO DEVELOP AND
EVOLVE...THIS WOULD/COULD HAVE BEEN MUCH WORSE THAN IT WILL BE.
STILL...THE CURRENT DEVELOPMENT OF THIS SYSTEM WARRANTS CONTINUED
MONITORING IN CASE THERE ARE SIGNIFICANT SPATIAL OR TEMPORAL
DIFFERENCES BETWEEN NOW AND THEN THAT MAY CAUSE POTENTIAL SNOWFALL
TO INCREASE. LATER SUNDAY EVENING/OVERNIGHT WILL BE THE ONLY
REALISTIC PERIOD WHERE MOST LOWER ELEVATIONS WILL SEE ANY CHANCE FOR
PRECIP REACHING THE GROUND AS TROF AXIS SWINGS THRU.

BY MON AFTERNOON...MOST TRACES OF THE STORM SYSTEM...BOTH SFC AND
ALOFT...WILL HAVE MOVED E TO SE OF WY...LEAVING BEHIND CLEARING
SKIES AND COLDER TEMPS. SLOW WARMING AND MOSTLY DRY CONDITIONS UNDER
CONTINUING NW FLOW UNTIL UNTIL AT LEAST THURSDAY...WHEN A TRANSITION
TO FLAT RIDGING MAY ENSUE. WINDS LOOK TO INCREASE ACROSS THE USUAL
SPOTS TUE NIGHT INTO WED MORNING. OTHERWISE...OVER THE FINAL THREE
DAYS OF THE FCST...THE ONLY AREA WHICH MAY HAVE SMALL CHCS FOR
PRECIP WILL BE ACROSS THE NW MOUNTAINS UNDER MODEST MID LVL TERRAIN
FORCED CONDITIONS..FAVORING THE UPR WRN SLOPES.
&&

.AVIATION.../00Z ISSUANCE/

HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION
THROUGH FRIDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND VFR
CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY. A GUSTY BREEZE WILL DEVELOP AT TIMES ON
FRIDAY...MAINLY IN VICINITY OF KRKS AND KCPR.
&&

.FIRE WEATHER...

A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TOMORROW FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES ON FRIDAY. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...HATTINGS
LONG TERM...BRAUN
AVIATION...HATTINGS
FIRE WEATHER...HATTINGS







000
FXUS65 KRIW 302110
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
310 PM MDT THU OCT 30 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT

A FAIRLY UNEVENTFUL FORECAST THROUGH THE SHORT TERM. SATELLITE
IMAGERY DOES SHOW SOME MID TO HIGH LEVEL CLOUDS MOVING OVER THE TOP
OF THE RIDGE SO SOME AREAS...ESPECIALLY IN THE NORTHERN AND EASTERN
PORTIONS OF THE COUNTY WARNING AREA WILL SEE A BROKEN DECK OF CLOUDS
BUT NO PRECIPITATION IS EXPECTED. THIS PATTERN IS EXPECTED TO
CONTINUE THROUGH TONIGHT AS WELL AND INTO TOMORROW. AS A RESULT...WE
HAVE INCREASED SKY COVER A BIT IN THOSE AREAS BUT ONLY TO PARTLY
CLOUDY FOR MOST AREAS. THE OTHER CONCERN WILL BE FOR INCREASE IN THE
BREEZE LATE TONIGHT AND ESPECIALLY TOMORROW AS A SYSTEM APPROACHES
FROM THE WEST. THIS WILL TIGHTEN THE PRESSURE GRADIENT A BIT AND
BRING A GUSTY SOUTHWESTERLY BREEZE...ESPECIALLY ACROSS THE FAVORED
AREAS LIKE FROM ROCK SPRINGS TO CASPER. HOWEVER...700 MILLIBAR WINDS
TOP OUT AT ONLY 35 KNOTS SO IT LOOKS ONLY BREEZY...NOT WINDY AND ANY
HIGH WIND HIGHLIGHTS ALMOST CERTAINLY WILL NOT BE NEEDED.
TEMPERATURES WILL CONTINUE TO BE WELL ABOVE NORMAL WITH HIGHS
POSSIBLY REACHING THE 70S IN SOME WARMER BASIN LOCATIONS ALTHOUGH IF
CLOUDS ARE A BIT MORE WIDESPREAD THIS MAY INHIBIT HEATING JUST A
BIT. AS FOR HALLOWEEN NIGHT AND THE ALL IMPORTANT TRICK OR TREATING
FORECAST...IT LOOKS LIKE A PARTLY TO MOSTLY CLEAR SKY AND
TEMPERATURES GENERALLY IN THE 40S AND 50S DEPENDING ON YOUR
ELEVATION SO THINGS LOOK GOOD FOR THE ANNUAL CANDY GATHERING. LATE
AT NIGHT AFTER THE KIDS HAVE HOPEFULLY GONE TO SLEEP...SOME MOISTURE
ADVECTING FROM THE SOUTH AND WEST COULD BRING A FEW SPRINKLES OR
FLURRIES TO THE HIGHER ELEVATIONS WEST OF THE DIVIDE BUT THESE LOOK
INCONSEQUENTIAL ENOUGH THAT WE LEFT THEM OUT OF THE FORECAST.

.LONG TERM...SATURDAY THROUGH THURSDAY

BEGINNING OF FCST...END OF UPR RIDGING WITH SOUTHWEST FLOW FIRMLY IN
PLACE AHEAD OF WRN CONUS TROF AND FIRST INFLUENCES OF JET STREAK/SW
BEING FELT OVR THE WRN FA. HOWEVER...LOW MOISTURE CONTENT OF THE
ATMOSPHERE AT THIS TIME WILL KEEP QPF ON THE LOW SIDE AT LEAST THRU
THE FIRST 12 HRS OF THE FCST. WEAK CYCLOGENESIS JUST STARTING TO
PROCEED OVR THE GREAT BASIN WITH LEE SIDE TROFFING SETTING EAST OF
THE BIGHORNS. AS SFC P GRAD INCREASES WITH THIS DEVELOPING STORM
SYSTEM...WIND SPEEDS ACROSS THE USUAL WIND CORRIDOR WITH ALSO INCREASE BY
SAT AFTERNOON...WITH GUSTS 45 TO 50 MPH COMMON INTO THE EVENING
PERIOD BEFORE DECREASING OVERNIGHT. THE WIND WILL RETURN AGAIN BY
SUNDAY AFTERNOON.

BY SAT NIGHT...ADDITIONAL CHANGES FROM THE
APPROACHING...INTENSIFYING AND EVOLVING SYSTEM REALLY START TO COME
INTO PLAY AS SFC/UPR LOW SPINS UP OVR NRN WY/SRN MT...ALONG/NEAR
INTERSECTION WITH LEE TROF. AS CYCLONE SPINS UP...EXPECT VERY STRONG
WINDS ALOFT INVOF LOW SAT NIGHT INTO SUN MORNING AFFECTING THE
MOUNTAIN PEAKS WEST OF BUFFALO FOR A SHORT PERIOD BEFORE THE LOW
MOVES OFF TO THE NNE. ACROSS THE WRN CWA...N/S ORIENTED JET MOVES
OVERHEAD...SUBSTANTIALLY INTENSIFYING PRECIP ASSOCIATED WITH...BY
THIS TIME...INCREASED  MOISTURE. THIS FIRST BURST OF PRECIP...AND
RAIN CHANGING SNOW...WILL MOVE QUICKLY NORTH AND INTO CNTRL MT BY
SUN MORNING. MOUNTAINS SHOULD RECEIVE UP TO 3 INCHES OF WET SNOWFALL
FROM THIS FIRST HIT. THEN...AS THE CYCLONE MATURES RATHER QUICKLY
WITH RAPIDLY DEVELOPING INSTABILITY UNDER COOL UPR TEMPS...AND
DECENT BAROCLINICITY...A LARGE AREA OF PRECIPITATION WILL BREAK OUT
WEST OF THE SFC LOW...WITH GREATEST INTENSITY NEARLY DIRECTLY UNDER
THE H5 TROF AXIS OVR NERN ID/WRN MT. THIS WILL RESULT IN A BIT
LIGHTER BUT MORE PERSISTENT RAINFALL/SNOWFALL ACROSS THE WRN TO NRN
CWA. ANOTHER AREA OF GOOD PRECIP WILL BE CO-LOCATED WITH THE UPR JET
FROM NCNTRL CO THRU SERN WY...WELL OUT OF THE FA. ATTM...IT WOULD
APPEAR THAT THE MOUNTAINS OF SW YELLOWSTONE AND PERHAPS THE TETONS
TO THE SOUTH WILL BE IN THE BEST POSITION FOR GREATEST SNOWFALL
POTENTIAL...WITH MUCH OF THIS REGION RECEIVING 3 TO 6 INCHES IN A 24
HR PERIOD...WITH LOCALIZED PREFERRED AREAS GETTING UP TO 8 INCHES.
PERHAPS ANOTHER INCH OR TWO MAY BE HAD SUNDAY NIGHT INTO MONDAY
MORNING...ALTHOUGH THIS IS MUCH MORE SPECULATION THAN EMPIRICAL
SCIENCE AT THIS POINT. LOWER ELEVATIONS LOOK TO BE THE RECIPIENTS OF
UP TO 3 INCHES OF SNOW OVER THE SAME PERIOD OF TIME. ALL THESE
SNOWFALL NUMBERS PUT THE WRN FA DANGEROUSLY CLOSE TO ADVISORY
CONDITIONS. IF THE LOCATION OF THE UPR AND SFC LOWS HAD PLACED
CYCLOGENESIS FURTHER EWD...OR WAS SLOWER TO DEVELOP AND
EVOLVE...THIS WOULD/COULD HAVE BEEN MUCH WORSE THAN IT WILL BE.
STILL...THE CURRENT DEVELOPMENT OF THIS SYSTEM WARRANTS CONTINUED
MONITORING IN CASE THERE ARE SIGNIFICANT SPATIAL OR TEMPORAL
DIFFERENCES BETWEEN NOW AND THEN THAT MAY CAUSE POTENTIAL SNOWFALL
TO INCREASE. LATER SUNDAY EVENING/OVERNIGHT WILL BE THE ONLY
REALISTIC PERIOD WHERE MOST LOWER ELEVATIONS WILL SEE ANY CHANCE FOR
PRECIP REACHING THE GROUND AS TROF AXIS SWINGS THRU.

BY MON AFTERNOON...MOST TRACES OF THE STORM SYSTEM...BOTH SFC AND
ALOFT...WILL HAVE MOVED E TO SE OF WY...LEAVING BEHIND CLEARING
SKIES AND COLDER TEMPS. SLOW WARMING AND MOSTLY DRY CONDITIONS UNDER
CONTINUING NW FLOW UNTIL UNTIL AT LEAST THURSDAY...WHEN A TRANSITION
TO FLAT RIDGING MAY ENSUE. WINDS LOOK TO INCREASE ACROSS THE USUAL
SPOTS TUE NIGHT INTO WED MORNING. OTHERWISE...OVER THE FINAL THREE
DAYS OF THE FCST...THE ONLY AREA WHICH MAY HAVE SMALL CHCS FOR
PRECIP WILL BE ACROSS THE NW MOUNTAINS UNDER MODEST MID LVL TERRAIN
FORCED CONDITIONS..FAVORING THE UPR WRN SLOPES.
&&

.AVIATION.../00Z ISSUANCE/

HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION
THROUGH FRIDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND VFR
CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY. A GUSTY BREEZE WILL DEVELOP AT TIMES ON
FRIDAY...MAINLY IN VICINITY OF KRKS AND KCPR.
&&

.FIRE WEATHER...

A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TOMORROW FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES ON FRIDAY. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...HATTINGS
LONG TERM...BRAUN
AVIATION...HATTINGS
FIRE WEATHER...HATTINGS







000
FXUS65 KRIW 302049
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
249 PM MDT THU OCT 30 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT

A FAIRLY UNEVENTFUL FORECAST THROUGH THE SHORT TERM. SATELLITE
IMAGERY DOES SHOW SOME MID TO HIGH LEVEL CLOUDS MOVING OVER THE TOP
OF THE RIDGE SO SOME AREAS...ESPECIALLY IN THE NORTHERN AND EASTERN
PORTIONS OF THE COUNTY WARNING AREA WILL SEE A BROKEN DECK OF CLOUDS
BUT NO PRECIPITATION IS EXPECTED. THIS PATTERN IS EXPECTED TO
CONTINUE THROUGH TONIGHT AS WELL AND INTO TOMORROW. AS A RESULT...WE
HAVE INCREASED SKY COVER A BIT IN THOSE AREAS BUT ONLY TO PARTLY
CLOUDY FOR MOST AREAS. THE OTHER CONCERN WILL BE FOR INCREASE IN THE
BREEZE LATE TONIGHT AND ESPECIALLY TOMORROW AS A SYSTEM APPROACHES
FROM THE WEST. THIS WILL TIGHTEN THE PRESSURE GRADIENT A BIT AND
BRING A GUSTY SOUTHWESTERLY BREEZE...ESPECIALLY ACROSS THE FAVORED
AREAS LIKE FROM ROCK SPRINGS TO CASPER. HOWEVER...700 MILLIBAR WINDS
TOP OUT AT ONLY 35 KNOTS SO IT LOOKS ONLY BREEZY...NOT WINDY AND ANY
HIGH WIND HIGHLIGHTS ALMOST CERTAINLY WILL NOT BE NEEDED.
TEMPERATURES WILL CONTINUE TO BE WELL ABOVE NORMAL WITH HIGHS
POSSIBLY REACHING THE 70S IN SOME WARMER BASIN LOCATIONS ALTHOUGH IF
CLOUDS ARE A BIT MORE WIDESPREAD THIS MAY INHIBIT HEATING JUST A
BIT. CLOUDS WILL THEN INCREASE ACROSS WESTERN WYOMING LATE AT NIGHT.
WE CAN`T RULE OUT A STRAY SPRINKLE OR FLURRY IN THE HIGHER
ELEVATIONS LATE AT NIGHT...BUT IT SO INCONSEQUENTIAL WE LEFT IT OUT
OF THE FORECAST.

.LONG TERM...SATURDAY THROUGH THURSDAY

BEGINNING OF FCST...END OF UPR RIDGING WITH SOUTHWEST FLOW FIRMLY IN
PLACE AHEAD OF WRN CONUS TROF AND FIRST INFLUENCES OF JET STREAK/SW
BEING FELT OVR THE WRN FA. HOWEVER...LOW MOISTURE CONTENT OF THE
ATMOSPHERE AT THIS TIME WILL KEEP QPF ON THE LOW SIDE AT LEAST THRU
THE FIRST 12 HRS OF THE FCST. WEAK CYCLOGENESIS JUST STARTING TO
PROCEED OVR THE GREAT BASIN WITH LEE SIDE TROFFING SETTING EAST OF
THE BIGHORNS. AS SFC P GRAD INCREASES WITH THIS DEVELOPING STORM
SYSTEM...WIND SPEEDS ACROSS THE USUAL WIND CORRIDOR WITH ALSO INCREASE BY
SAT AFTERNOON...WITH GUSTS 45 TO 50 MPH COMMON INTO THE EVENING
PERIOD BEFORE DECREASING OVERNIGHT. THE WIND WILL RETURN AGAIN BY
SUNDAY AFTERNOON.

BY SAT NIGHT...ADDITIONAL CHANGES FROM THE
APPROACHING...INTENSIFYING AND EVOLVING SYSTEM REALLY START TO COME
INTO PLAY AS SFC/UPR LOW SPINS UP OVR NRN WY/SRN MT...ALONG/NEAR
INTERSECTION WITH LEE TROF. AS CYCLONE SPINS UP...EXPECT VERY STRONG
WINDS ALOFT INVOF LOW SAT NIGHT INTO SUN MORNING AFFECTING THE
MOUNTAIN PEAKS WEST OF BUFFALO FOR A SHORT PERIOD BEFORE THE LOW
MOVES OFF TO THE NNE. ACROSS THE WRN CWA...N/S ORIENTED JET MOVES
OVERHEAD...SUBSTANTIALLY INTENSIFYING PRECIP ASSOCIATED WITH...BY
THIS TIME...INCREASED  MOISTURE. THIS FIRST BURST OF PRECIP...AND
RAIN CHANGING SNOW...WILL MOVE QUICKLY NORTH AND INTO CNTRL MT BY
SUN MORNING. MOUNTAINS SHOULD RECEIVE UP TO 3 INCHES OF WET SNOWFALL
FROM THIS FIRST HIT. THEN...AS THE CYCLONE MATURES RATHER QUICKLY
WITH RAPIDLY DEVELOPING INSTABILITY UNDER COOL UPR TEMPS...AND
DECENT BAROCLINICITY...A LARGE AREA OF PRECIPITATION WILL BREAK OUT
WEST OF THE SFC LOW...WITH GREATEST INTENSITY NEARLY DIRECTLY UNDER
THE H5 TROF AXIS OVR NERN ID/WRN MT. THIS WILL RESULT IN A BIT
LIGHTER BUT MORE PERSISTENT RAINFALL/SNOWFALL ACROSS THE WRN TO NRN
CWA. ANOTHER AREA OF GOOD PRECIP WILL BE CO-LOCATED WITH THE UPR JET
FROM NCNTRL CO THRU SERN WY...WELL OUT OF THE FA. ATTM...IT WOULD
APPEAR THAT THE MOUNTAINS OF SW YELLOWSTONE AND PERHAPS THE TETONS
TO THE SOUTH WILL BE IN THE BEST POSITION FOR GREATEST SNOWFALL
POTENTIAL...WITH MUCH OF THIS REGION RECEIVING 3 TO 6 INCHES IN A 24
HR PERIOD...WITH LOCALIZED PREFERRED AREAS GETTING UP TO 8 INCHES.
PERHAPS ANOTHER INCH OR TWO MAY BE HAD SUNDAY NIGHT INTO MONDAY
MORNING...ALTHOUGH THIS IS MUCH MORE SPECULATION THAN EMPIRICAL
SCIENCE AT THIS POINT. LOWER ELEVATIONS LOOK TO BE THE RECIPIENTS OF
UP TO 3 INCHES OF SNOW OVER THE SAME PERIOD OF TIME. ALL THESE
SNOWFALL NUMBERS PUT THE WRN FA DANGEROUSLY CLOSE TO ADVISORY
CONDITIONS. IF THE LOCATION OF THE UPR AND SFC LOWS HAD PLACED
CYCLOGENESIS FURTHER EWD...OR WAS SLOWER TO DEVELOP AND
EVOLVE...THIS WOULD/COULD HAVE BEEN MUCH WORSE THAN IT WILL BE.
STILL...THE CURRENT DEVELOPMENT OF THIS SYSTEM WARRANTS CONTINUED
MONITORING IN CASE THERE ARE SIGNIFICANT SPATIAL OR TEMPORAL
DIFFERENCES BETWEEN NOW AND THEN THAT MAY CAUSE POTENTIAL SNOWFALL
TO INCREASE. LATER SUNDAY EVENING/OVERNIGHT WILL BE THE ONLY
REALISTIC PERIOD WHERE MOST LOWER ELEVATIONS WILL SEE ANY CHANCE FOR
PRECIP REACHING THE GROUND AS TROF AXIS SWINGS THRU.

BY MON AFTERNOON...MOST TRACES OF THE STORM SYSTEM...BOTH SFC AND
ALOFT...WILL HAVE MOVED E TO SE OF WY...LEAVING BEHIND CLEARING
SKIES AND COLDER TEMPS. SLOW WARMING AND MOSTLY DRY CONDITIONS UNDER
CONTINUING NW FLOW UNTIL UNTIL AT LEAST THURSDAY...WHEN A TRANSITION
TO FLAT RIDGING MAY ENSUE. WINDS LOOK TO INCREASE ACROSS THE USUAL
SPOTS TUE NIGHT INTO WED MORNING. OTHERWISE...OVER THE FINAL THREE
DAYS OF THE FCST...THE ONLY AREA WHICH MAY HAVE SMALL CHCS FOR
PRECIP WILL BE ACROSS THE NW MOUNTAINS UNDER MODEST MID LVL TERRAIN
FORCED CONDITIONS..FAVORING THE UPR WRN SLOPES.
&&

.AVIATION.../00Z ISSUANCE/

HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION
THROUGH FRIDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND VFR
CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY. A GUSTY BREEZE WILL DEVELOP AT TIMES ON
FRIDAY...MAINLY IN VICINITY OF KRKS AND KCPR.
&&

.FIRE WEATHER...

A RIDGE OF HIGH PRESSURE IS EXPECTED TO LAST THROUGH SATURDAY
MORNING AND BRING MAINLY DRY WEATHER. A GUSTY SOUTHWESTERLY BREEZE
WILL DEVELOP TOMORROW FROM THE RED DESERT THROUGH NATRONA AND
JOHNSON COUNTIES ON FRIDAY. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...HATTINGS
LONG TERM...BRAUN
AVIATION...HATTINGS
FIRE WEATHER...HATTINGS







000
FXUS65 KRIW 301728
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1128 AM MDT THU OCT 30 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
AT LEAST TWO MORE PLEASANT FALL DAYS ARE IN STORE THROUGH FRIDAY
WITH PERHAPS ANOTHER BONUS DAY IN THE EASTERN CWA SATURDAY.
TEMPERATURES WILL WARM THROUGH SATURDAY ACROSS THE EAST AND THROUGH
FRIDAY ELSEWHERE BEFORE INCREASING CLOUDS AND PRECIP COOL THINGS OFF
SATURDAY. THE RIDGE AXIS OVER THE PACIFIC STATES WILL SHIFT EAST AND
BE OVERHEAD BY THURSDAY NIGHT. THEN THE FLOW WILL BACK TO A MORE
SOUTHWEST FLOW USHERING IN THE AFOREMENTIONED WARM AIR OVER OUR CWA
FRIDAY. A 1037MB SFC HIGH DIVING SSE ACROSS THE NORTHERN PLAINS WILL
NOT DRIVE A BACKDOOR COOL FRONT FAR ENOUGH WEST TO AFFECT OUR CWA
THURSDAY. THE TROUGH ASSOCIATED WITH THE CIRCULATION OFF THE PACIFIC
COAST OVER 50N/145W WILL SHIFT EAST AND MAKE LANDFALL SATURDAY AND
THEN APPROACH THE ROCKIES BY 12Z SUNDAY. BOTH THE GFS AND THE EURO
CLOSE OFF AND TRACK THE ASCT UPPER LOW NORTHEAST ACROSS NW WY WITH
THE EURO A BIT FASTER THAN THE GFS. EARLIER RUNS OF THE GFS HAD THE
LOW TRACKING NORTHEAST FARTHER SOUTH ACROSS CENTRAL WY BUT NOW MORE
RESEMBLES THE EURO. THE GFS TRACKS THE LOW ACROSS NW WY AROUND 12Z
SUNDAY. SOUTHWEST SFC WINDS WILL INCREASE FRIDAY AHEAD OF THIS
APPROACHING PACIFIC WEATHER SYSTEM.

AS A RESULT OF THIS WX SYSTEM...SATURDAY IS SHAPING UP TO BE AN
INTERESTING DAY. A WELL DEVELOPED SFC LOW WILL TRACK FROM EASTERN
IDAHO TO ALONG THE WY/MT BORDER SATURDAY COMPLETE WITH A WELL
DEVELOPED WARM FRONT AND PACIFIC COLD FRONT AND A LIKELY CLASSIC
COMMA CLOUD SIGNATURE. THE H7 LOW WILL TRACK NORTHEAST FROM IDAHO TO
MT WITH A WEAKER H7 CIRCULATION OVER NW WY SATURDAY. HIGHEST POPS
HAVE BEEN PAINTED ACROSS WESTERN WY BY SATURDAY EVE WITH LIKELY POPS
AND AT LEAST CHC POPS UP NORTH. ISOLD IF ANY IN THE CENTRAL AND
EAST. SOME LEFT FRONT QUAD DYNAMICS MAY COME INTO PLAY SAT NT AS THE
JET SAGS SOUTH. WE SHOULD SEE SOME EMBEDDED THUNDERSTORMS IN WESTERN
WY WHERE LIFTED INDICES WILL BE NEGATIVE. SOUTHWEST WINDS WILL
INCREASE SATURDAY OVER WHAT OCCURS FRIDAY AS THE TROUGH NEARS THE
CWA...ESPECIALLY FROM KRKS TO KCPR. RAIN IN THE WEST WILL TURN TO
SNOW SAT NIGHT AS H7 TEMPS DROP -7C.

.LONG TERM...SUNDAY THROUGH THURSDAY

GFS HAS TRENDED FURTHER WEST WITH THE TRACK OF OUR WEEKEND SYSTEM
AS EXPECTED LAST NIGHT. AT THE START OF THIS PERIOD...THE MAIN
CIRCULATION WILL LIKELY BE AROUND THE SWRN CORNER OF MT WITH
SNOW FALLING ACROSS MUCH OF THE WEST. AS THE LOW CONTINUES TO MOVE
OFF TO THE NE...FAVORABLE NW FLOW BEHIND IT SHOULD KEEP SNOW GOING
ACROSS THE WEST...SPREADING INTO THE BIGHORN MOUNTAINS. BY SUNDAY
NIGHT...UPPER LOW WILL LIKELY BE OVER NERN MT WITH COLD...CYCLONIC
NW FLOW OVER THE AREA. COLDEST H5 AIR IS FORECAST TO ARRIVE LATE
SUNDAY NIGHT. THIS SCENARIO CAN RESULT IN SNOW BANDS OVER CENTRAL
WYO INCLUDING THE WIND RIVER BASIN. GFS IS MOST FAVORABLE WITH
MOST OF THE OTHER MODELS PROVIDING AT LEAST SOME SUPPORT. WILL PUT
IN SOME CHANCE POPS SPREADING SE INTO THE WIND RIVER BASIN AND WRN
NATRONA LATE SUNDAY NIGHT WITH A FEW LINGERING INTO MONDAY MRNG.
COULD SEE 3 TO 6 INCHES OF SNOW ACROSS THE WRN MTNS SUNDAY INTO
SUNDAY NIGHT WITH LOCALLY HIGHER AMOUNTS IN FAVORED NW FLOW. COLDEST
H7 AIR COMES IN BEHIND THIS TROUGH ON MONDAY FOR THE COLDEST DAY OF
THE EXTENDED. BOTH THE HIGHS MONDAY AND THE LOWS MONDAY NIGHT. THEN
SLOW MODERATION THE REST OF THE PERIOD WITH POTENTIAL FOR A MILD DAY
THURSDAY WITH SOME WIND AND BETTER MIXING. RAISED TEMPERATURES SOME
AT THE END OF THE PERIOD BUT NOT AS HIGH AS THEY COULD BE IF WE CAN
FULLY MIX THE ATMOSPHERE BY THURSDAY WHEN POTENTIAL WINDS KICK IN.

&&

.AVIATION.../18Z ISSUANCE/
HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION LATER
TONIGHT AND THURSDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND
VFR CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY. A GUSTY BREEZE WILL DEVELOP AT TIMES ON
FRIDAY...MAINLY IN VICINITY OF KRKS AND KCPR.

&&

.FIRE WEATHER...
AN AREA OF HIGH PRESSURE WILL BUILD INTO THE AREA BRINGING BENIGN
CONDITIONS FOR TODAY. THIS RIDGE OF HIGH PRESSURE IS EXPECTED TO
LAST THROUGH SATURDAY MORNING. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.


&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...HATTINGS
FIRE WEATHER...LIPSON













000
FXUS65 KRIW 301728
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1128 AM MDT THU OCT 30 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
AT LEAST TWO MORE PLEASANT FALL DAYS ARE IN STORE THROUGH FRIDAY
WITH PERHAPS ANOTHER BONUS DAY IN THE EASTERN CWA SATURDAY.
TEMPERATURES WILL WARM THROUGH SATURDAY ACROSS THE EAST AND THROUGH
FRIDAY ELSEWHERE BEFORE INCREASING CLOUDS AND PRECIP COOL THINGS OFF
SATURDAY. THE RIDGE AXIS OVER THE PACIFIC STATES WILL SHIFT EAST AND
BE OVERHEAD BY THURSDAY NIGHT. THEN THE FLOW WILL BACK TO A MORE
SOUTHWEST FLOW USHERING IN THE AFOREMENTIONED WARM AIR OVER OUR CWA
FRIDAY. A 1037MB SFC HIGH DIVING SSE ACROSS THE NORTHERN PLAINS WILL
NOT DRIVE A BACKDOOR COOL FRONT FAR ENOUGH WEST TO AFFECT OUR CWA
THURSDAY. THE TROUGH ASSOCIATED WITH THE CIRCULATION OFF THE PACIFIC
COAST OVER 50N/145W WILL SHIFT EAST AND MAKE LANDFALL SATURDAY AND
THEN APPROACH THE ROCKIES BY 12Z SUNDAY. BOTH THE GFS AND THE EURO
CLOSE OFF AND TRACK THE ASCT UPPER LOW NORTHEAST ACROSS NW WY WITH
THE EURO A BIT FASTER THAN THE GFS. EARLIER RUNS OF THE GFS HAD THE
LOW TRACKING NORTHEAST FARTHER SOUTH ACROSS CENTRAL WY BUT NOW MORE
RESEMBLES THE EURO. THE GFS TRACKS THE LOW ACROSS NW WY AROUND 12Z
SUNDAY. SOUTHWEST SFC WINDS WILL INCREASE FRIDAY AHEAD OF THIS
APPROACHING PACIFIC WEATHER SYSTEM.

AS A RESULT OF THIS WX SYSTEM...SATURDAY IS SHAPING UP TO BE AN
INTERESTING DAY. A WELL DEVELOPED SFC LOW WILL TRACK FROM EASTERN
IDAHO TO ALONG THE WY/MT BORDER SATURDAY COMPLETE WITH A WELL
DEVELOPED WARM FRONT AND PACIFIC COLD FRONT AND A LIKELY CLASSIC
COMMA CLOUD SIGNATURE. THE H7 LOW WILL TRACK NORTHEAST FROM IDAHO TO
MT WITH A WEAKER H7 CIRCULATION OVER NW WY SATURDAY. HIGHEST POPS
HAVE BEEN PAINTED ACROSS WESTERN WY BY SATURDAY EVE WITH LIKELY POPS
AND AT LEAST CHC POPS UP NORTH. ISOLD IF ANY IN THE CENTRAL AND
EAST. SOME LEFT FRONT QUAD DYNAMICS MAY COME INTO PLAY SAT NT AS THE
JET SAGS SOUTH. WE SHOULD SEE SOME EMBEDDED THUNDERSTORMS IN WESTERN
WY WHERE LIFTED INDICES WILL BE NEGATIVE. SOUTHWEST WINDS WILL
INCREASE SATURDAY OVER WHAT OCCURS FRIDAY AS THE TROUGH NEARS THE
CWA...ESPECIALLY FROM KRKS TO KCPR. RAIN IN THE WEST WILL TURN TO
SNOW SAT NIGHT AS H7 TEMPS DROP -7C.

.LONG TERM...SUNDAY THROUGH THURSDAY

GFS HAS TRENDED FURTHER WEST WITH THE TRACK OF OUR WEEKEND SYSTEM
AS EXPECTED LAST NIGHT. AT THE START OF THIS PERIOD...THE MAIN
CIRCULATION WILL LIKELY BE AROUND THE SWRN CORNER OF MT WITH
SNOW FALLING ACROSS MUCH OF THE WEST. AS THE LOW CONTINUES TO MOVE
OFF TO THE NE...FAVORABLE NW FLOW BEHIND IT SHOULD KEEP SNOW GOING
ACROSS THE WEST...SPREADING INTO THE BIGHORN MOUNTAINS. BY SUNDAY
NIGHT...UPPER LOW WILL LIKELY BE OVER NERN MT WITH COLD...CYCLONIC
NW FLOW OVER THE AREA. COLDEST H5 AIR IS FORECAST TO ARRIVE LATE
SUNDAY NIGHT. THIS SCENARIO CAN RESULT IN SNOW BANDS OVER CENTRAL
WYO INCLUDING THE WIND RIVER BASIN. GFS IS MOST FAVORABLE WITH
MOST OF THE OTHER MODELS PROVIDING AT LEAST SOME SUPPORT. WILL PUT
IN SOME CHANCE POPS SPREADING SE INTO THE WIND RIVER BASIN AND WRN
NATRONA LATE SUNDAY NIGHT WITH A FEW LINGERING INTO MONDAY MRNG.
COULD SEE 3 TO 6 INCHES OF SNOW ACROSS THE WRN MTNS SUNDAY INTO
SUNDAY NIGHT WITH LOCALLY HIGHER AMOUNTS IN FAVORED NW FLOW. COLDEST
H7 AIR COMES IN BEHIND THIS TROUGH ON MONDAY FOR THE COLDEST DAY OF
THE EXTENDED. BOTH THE HIGHS MONDAY AND THE LOWS MONDAY NIGHT. THEN
SLOW MODERATION THE REST OF THE PERIOD WITH POTENTIAL FOR A MILD DAY
THURSDAY WITH SOME WIND AND BETTER MIXING. RAISED TEMPERATURES SOME
AT THE END OF THE PERIOD BUT NOT AS HIGH AS THEY COULD BE IF WE CAN
FULLY MIX THE ATMOSPHERE BY THURSDAY WHEN POTENTIAL WINDS KICK IN.

&&

.AVIATION.../18Z ISSUANCE/
HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION LATER
TONIGHT AND THURSDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND
VFR CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY. A GUSTY BREEZE WILL DEVELOP AT TIMES ON
FRIDAY...MAINLY IN VICINITY OF KRKS AND KCPR.

&&

.FIRE WEATHER...
AN AREA OF HIGH PRESSURE WILL BUILD INTO THE AREA BRINGING BENIGN
CONDITIONS FOR TODAY. THIS RIDGE OF HIGH PRESSURE IS EXPECTED TO
LAST THROUGH SATURDAY MORNING. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.


&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...HATTINGS
FIRE WEATHER...LIPSON













000
FXUS65 KRIW 300904
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
304 AM MDT THU OCT 30 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
AT LEAST TWO MORE PLEASANT FALL DAYS ARE IN STORE THROUGH FRIDAY
WITH PERHAPS ANOTHER BONUS DAY IN THE EASTERN CWA SATURDAY.
TEMPERATURES WILL WARM THROUGH SATURDAY ACROSS THE EAST AND THROUGH
FRIDAY ELSEWHERE BEFORE INCREASING CLOUDS AND PRECIP COOL THINGS OFF
SATURDAY. THE RIDGE AXIS OVER THE PACIFIC STATES WILL SHIFT EAST AND
BE OVERHEAD BY THURSDAY NIGHT. THEN THE FLOW WILL BACK TO A MORE
SOUTHWEST FLOW USHERING IN THE AFOREMENTIONED WARM AIR OVER OUR CWA
FRIDAY. A 1037MB SFC HIGH DIVING SSE ACROSS THE NORTHERN PLAINS WILL
NOT DRIVE A BACKDOOR COOL FRONT FAR ENOUGH WEST TO AFFECT OUR CWA
THURSDAY. THE TROUGH ASSOCIATED WITH THE CIRCULATION OFF THE PACIFIC
COAST OVER 50N/145W WILL SHIFT EAST AND MAKE LANDFALL SATURDAY AND
THEN APPROACH THE ROCKIES BY 12Z SUNDAY. BOTH THE GFS AND THE EURO
CLOSE OFF AND TRACK THE ASCT UPPER LOW NORTHEAST ACROSS NW WY WITH
THE EURO A BIT FASTER THAN THE GFS. EARLIER RUNS OF THE GFS HAD THE
LOW TRACKING NORTHEAST FARTHER SOUTH ACROSS CENTRAL WY BUT NOW MORE
RESEMBLES THE EURO. THE GFS TRACKS THE LOW ACROSS NW WY AROUND 12Z
SUNDAY. SOUTHWEST SFC WINDS WILL INCREASE FRIDAY AHEAD OF THIS
APPROACHING PACIFIC WEATHER SYSTEM.

AS A RESULT OF THIS WX SYSTEM...SATURDAY IS SHAPING UP TO BE AN
INTERESTING DAY. A WELL DEVELOPED SFC LOW WILL TRACK FROM EASTERN
IDAHO TO ALONG THE WY/MT BORDER SATURDAY COMPLETE WITH A WELL
DEVELOPED WARM FRONT AND PACIFIC COLD FRONT AND A LIKELY CLASSIC
COMMA CLOUD SIGNATURE. THE H7 LOW WILL TRACK NORTHEAST FROM IDAHO TO
MT WITH A WEAKER H7 CIRCULATION OVER NW WY SATURDAY. HIGHEST POPS
HAVE BEEN PAINTED ACROSS WESTERN WY BY SATURDAY EVE WITH LIKELY POPS
AND AT LEAST CHC POPS UP NORTH. ISOLD IF ANY IN THE CENTRAL AND
EAST. SOME LEFT FRONT QUAD DYNAMICS MAY COME INTO PLAY SAT NT AS THE
JET SAGS SOUTH. WE SHOULD SEE SOME EMBEDDED THUNDERSTORMS IN WESTERN
WY WHERE LIFTED INDICES WILL BE NEGATIVE. SOUTHWEST WINDS WILL
INCREASE SATURDAY OVER WHAT OCCURS FRIDAY AS THE TROUGH NEARS THE
CWA...ESPECIALLY FROM KRKS TO KCPR. RAIN IN THE WEST WILL TURN TO SNOW
SAT NIGHT AS H7 TEMPS DROP -7C.

.LONG TERM...SUNDAY THROUGH THURSDAY

GFS HAS TRENDED FURTHER WEST WITH THE TRACK OF OUR WEEKEND SYSTEM
AS EXPECTED LAST NIGHT. AT THE START OF THIS PERIOD...THE MAIN
CIRCULATION WILL LIKELY BE AROUND THE SWRN CORNER OF MT WITH
SNOW FALLING ACROSS MUCH OF THE WEST. AS THE LOW CONTINUES TO MOVE
OFF TO THE NE...FAVORABLE NW FLOW BEHIND IT SHOULD KEEP SNOW GOING
ACROSS THE WEST...SPREADING INTO THE BIGHORN MOUNTAINS. BY SUNDAY
NIGHT...UPPER LOW WILL LIKELY BE OVER NERN MT WITH COLD...CYCLONIC
NW FLOW OVER THE AREA. COLDEST H5 AIR IS FORECAST TO ARRIVE LATE
SUNDAY NIGHT. THIS SCENARIO CAN RESULT IN SNOW BANDS OVER CENTRAL
WYO INCLUDING THE WIND RIVER BASIN. GFS IS MOST FAVORABLE WITH
MOST OF THE OTHER MODELS PROVIDING AT LEAST SOME SUPPORT. WILL PUT
IN SOME CHANCE POPS SPREADING SE INTO THE WIND RIVER BASIN AND WRN
NATRONA LATE SUNDAY NIGHT WITH A FEW LINGERING INTO MONDAY MRNG. COULD
SEE 3 TO 6 INCHES OF SNOW ACROSS THE WRN MTNS SUNDAY INTO SUNDAY
NIGHT WITH LOCALLY HIGHER AMOUNTS IN FAVORED NW FLOW. COLDEST H7
AIR COMES IN BEHIND THIS TROUGH ON MONDAY FOR THE COLDEST DAY OF
THE EXTENDED. BOTH THE HIGHS MONDAY AND THE LOWS MONDAY NIGHT.
THEN SLOW MODERATION THE REST OF THE PERIOD WITH POTENTIAL FOR A
MILD DAY THURSDAY WITH SOME WIND AND BETTER MIXING. RAISED
TEMPERATURES SOME AT THE END OF THE PERIOD BUT NOT AS HIGH AS THEY
COULD BE IF WE CAN FULLY MIX THE ATMOSPHERE BY THURSDAY WHEN
POTENTIAL WINDS KICK IN.

&&

.AVIATION.../12Z ISSUANCE/
HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION LATER
TONIGHT AND THURSDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND
VFR CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY.

&&

.FIRE WEATHER...
AN AREA OF HIGH PRESSURE WILL BUILD INTO THE AREA BRINGING BENIGN
CONDITIONS FOR TODAY. THIS RIDGE OF HIGH PRESSURE IS EXPECTED TO
LAST THROUGH SATURDAY MORNING. THE NEXT POTENTIAL ROUND OF
PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS AN AREA
OF LOW PRESSURE APPROACHES WESTERN WYOMING.


&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...KPL
FIRE WEATHER...LIPSON










000
FXUS65 KRIW 300440
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1040 PM MDT WED OCT 29 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY

A WEAK WAVE OF LOW PRESSURE MOVING THROUGH THE AREA WILL CONTINUE TO
BRING SOME ISOLATED SHOWER ACTIVITY TODAY...MAINLY OVER THE HIGHER
TERRAIN. SOME MOUNTAIN ENHANCED CLOUDS WILL REMAIN OVER THE AREA AS
WELL.

THE WAVE GENERATING SOME PRECIPITATION SHOULD GENERALLY BE THROUGH
THE AREA BY THURSDAY MORNING. A BUILDING RIDGE IS THEN EXPECTED
BEHIND THE DEPARTURE OF THE WAVE. THIS HIGH PRESSURE WILL RESULT IN
WARMING TEMPERATURES... LIGHT WIND...AND DRY CONDITIONS THROUGH
THURSDAY AFTERNOON.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

RIDGING WILL CONTROL THE WEATHER FOR THURSDAY NIGHT AND BRING A
MAINLY CLEAR AND SEASONABLY CHILLY NIGHT. THIS AFOREMENTIONED RIDGE
WILL CONTINUE TO BRING DRY WEATHER THROUGH FRIDAY...ALTHOUGH WITH A
TIGHTENING PRESSURE GRADIENT WITH THE APPROACH OF A SYSTEM FROM THE
WEST IT WILL BE BREEZY AT TIMES IN THE FAVORED LOCATIONS. NOW OF
COURSE...THE MILLION DOLLAR QUESTION IS WHAT WILL THE WEATHER BE
LIKE FOR ALL OF THE LITTLE GHOSTS...GOBLINS AND GHOULS WHAT WILL BE
GOING OUT ON THE ANNUAL SEARCH FOR CANDY ON FRIDAY EVENING. AND THE
ANSWER IS...IT LOOKS FAIRLY NICE. EXPECT DRY WEATHER FOR ALL
LOCATIONS WITH A FEW MORE CLOUDS IN THE WEST AND A BIT OF A BREEZE
IN THE WIND CORRIDOR. BY THE TIME THE BIG KIDS GO OUT TO PARTY IN
THE EVENING IT WILL BE CHILLY...BUT NOTHING UNEXPECTED FOR THE LAST
DAY OF OCTOBER IN WYOMING.

CHANGES WILL BEGIN ON SATURDAY AS THE WEATHER SYSTEM MOVES TOWARDS
THE AREA FROM THE SOUTH AND WEST. THE MODELS CONTINUE TO HAVE A VAST
MAJORITY OF PLACES DRY THROUGH SATURDAY MORNING. PRECIPITATION WILL
SPREAD INTO AREAS WEST OF THE DIVIDE THROUGH THE AFTERNOON.
HOWEVER...ALL THE MODELS HAVE BACKED OFF ON PRECIPITATION AMOUNTS SO
ANY RAIN OR SNOW SHOULD BE MINOR. MEANWHILE...EAST OF THE DIVIDE
EXPECT DRY WEATHER AND WARM WEATHER. HOWEVER...THE COMPLICATION WILL
BE A GUSTY SOUTHWESTERLY WIND WITH SOME GUSTS PAST 40 MPH AT TIMES.
SOME OF THE WARMER BASIN LOCATIONS COULD SEE HIGH TEMPERATURES RISE
INTO THE 70S. BOTH THE EUROPEAN AND GFS ARE ALSO FAIRLY CONSISTENT
IN KEEPING ALMOST ALL OF THE PRECIPITATION WEST OF THE DIVIDE FOR
SATURDAY NIGHT AS WELL. WE KEPT A SLIGHT CHANCE OF SHOWERS IN EAST
OF THE DIVIDE FOR NOW BUT FUTURE SHIFTS MAY WANT TO CONSIDER TAKING
IT OUT IF THIS TREND CONTINUES. THERE COULD BE A FEW INCHES OF SNOW
FOR THE HIGHER ELEVATIONS OF THE WEST...BUT AT THIS TIME IT LOOKS TO
REMAIN SUB-ADVISORY. AS FOR SUNDAY...BOTH MODELS TAKE MOST OF THE
ENERGY TO THE NORTH AS THE SYSTEM BUMPS INTO THE RIDGE TO THE EAST.
THE CURRENT FORECAST WITH HIGHER POPS LOOKED REASONABLE AS A RESULT.
THE BIG CHANGE STILL LOOKS TO BE TEMPERATURES WITH HIGHS 10 TO 20
DEGREES COLDER THAN ON SATURDAY.

BY MONDAY...THIS ENERGY WILL MOVE AWAY TO THE EAST. HOWEVER...THE
TROUGH AXIS WILL STILL BE OVER THE AREA. IN ADDITION...THE MODELS
SHOW ANOTHER PIECE OF ENERGY MOVING UP FROM THE SOUTH THAT COULD
BRING A FEW SHOWERS...ESPECIALLY TO THE SOUTH. THE MODELS ARE
DISAGREEING ON TIMING...SO FAR NOW WE MADE FEW CHANGES. THERE ARE
ALSO DIFFERENCES FROM TUESDAY AND ONWARD...THE GFS HAS A FLATTER
FLOW WITH ANOTHER SHORTWAVE MOVING INTO WYOMING FOR TUESDAY.
MEANWHILE...THE EUROPEAN HAS A STRONGER RIDGE AND KEEPS THE AREA
WARMER AND DRIER. ONLY TIME WILL TELL WHAT WILL HAPPEN AT THAT POINT.

&&

.AVIATION.../06Z DISCUSSION/

HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS INTO THE REGION LATER
TONIGHT AND THURSDAY. THIS WILL RESULT IN A GENERALLY CLEAR SKY AND
VFR CONDITIONS ON BOTH SIDES OF THE CONTINENTAL DIVIDE...AND THEN
CONTINUE INTO FRIDAY.

&&

.FIRE WEATHER...

A WEAK WAVE OF LOW PRESSURE WILL KEEP SOME ISOLATED...GENERALLY
MOUNTAIN RELATED SHOWER ACTIVITY ACROSS WESTERN AND CENTRAL WYOMING
THROUGH THIS EVENING. AS THE SYSTEM COMPLETES ITS TRAVEL THROUGH THE
FORECAST AREA...AN AREA OF HIGH PRESSURE WILL BUILD IN BEHIND IT
BRINGING BENIGN CONDITIONS FOR THURSDAY. THIS RIDGE OF HIGH PRESSURE
IS EXPECTED TO LAST THROUGH SATURDAY MORNING. THE NEXT POTENTIAL
ROUND OF PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS
AN AREA OF LOW PRESSURE APPROACHES WESTERN WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM...BRANHAM
LONG TERM...HATTINGS
AVIATION...KPL
FIRE WEATHER...BRANHAM






000
FXUS65 KRIW 292117
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
317 PM MDT WED OCT 29 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY

A WEAK WAVE OF LOW PRESSURE MOVING THROUGH THE AREA WILL CONTINUE TO
BRING SOME ISOLATED SHOWER ACTIVITY TODAY...MAINLY OVER THE HIGHER
TERRAIN. SOME MOUNTAIN ENHANCED CLOUDS WILL REMAIN OVER THE AREA AS
WELL.

THE WAVE GENERATING SOME PRECIPITATION SHOULD GENERALLY BE THROUGH
THE AREA BY THURSDAY MORNING. A BUILDING RIDGE IS THEN EXPECTED
BEHIND THE DEPARTURE OF THE WAVE. THIS HIGH PRESSURE WILL RESULT IN
WARMING TEMPERATURES... LIGHT WIND...AND DRY CONDITIONS THROUGH
THURSDAY AFTERNOON.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

RIDGING WILL CONTROL THE WEATHER FOR THURSDAY NIGHT AND BRING A
MAINLY CLEAR AND SEASONABLY CHILLY NIGHT. THIS AFOREMENTIONED RIDGE
WILL CONTINUE TO BRING DRY WEATHER THROUGH FRIDAY...ALTHOUGH WITH A
TIGHTENING PRESSURE GRADIENT WITH THE APPROACH OF A SYSTEM FROM THE
WEST IT WILL BE BREEZY AT TIMES IN THE FAVORED LOCATIONS. NOW OF
COURSE...THE MILLION DOLLAR QUESTION IS WHAT WILL THE WEATHER BE
LIKE FOR ALL OF THE LITTLE GHOSTS...GOBLINS AND GHOULS WHAT WILL BE
GOING OUT ON THE ANNUAL SEARCH FOR CANDY ON FRIDAY EVENING. AND THE
ANSWER IS...IT LOOKS FAIRLY NICE. EXPECT DRY WEATHER FOR ALL
LOCATIONS WITH A FEW MORE CLOUDS IN THE WEST AND A BIT OF A BREEZE
IN THE WIND CORRIDOR. BY THE TIME THE BIG KIDS GO OUT TO PARTY IN
THE EVENING IT WILL BE CHILLY...BUT NOTHING UNEXPECTED FOR THE LAST
DAY OF OCTOBER IN WYOMING.

CHANGES WILL BEGIN ON SATURDAY AS THE WEATHER SYSTEM MOVES TOWARDS
THE AREA FROM THE SOUTH AND WEST. THE MODELS CONTINUE TO HAVE A VAST
MAJORITY OF PLACES DRY THROUGH SATURDAY MORNING. PRECIPITATION WILL
SPREAD INTO AREAS WEST OF THE DIVIDE THROUGH THE AFTERNOON.
HOWEVER...ALL THE MODELS HAVE BACKED OFF ON PRECIPITATION AMOUNTS SO
ANY RAIN OR SNOW SHOULD BE MINOR. MEANWHILE...EAST OF THE DIVIDE
EXPECT DRY WEATHER AND WARM WEATHER. HOWEVER...THE COMPLICATION WILL
BE A GUSTY SOUTHWESTERLY WIND WITH SOME GUSTS PAST 40 MPH AT TIMES.
SOME OF THE WARMER BASIN LOCATIONS COULD SEE HIGH TEMPERATURES RISE
INTO THE 70S. BOTH THE EUROPEAN AND GFS ARE ALSO FAIRLY CONSISTENT
IN KEEPING ALMOST ALL OF THE PRECIPITATION WEST OF THE DIVIDE FOR
SATURDAY NIGHT AS WELL. WE KEPT A SLIGHT CHANCE OF SHOWERS IN EAST
OF THE DIVIDE FOR NOW BUT FUTURE SHIFTS MAY WANT TO CONSIDER TAKING
IT OUT IF THIS TREND CONTINUES. THERE COULD BE A FEW INCHES OF SNOW
FOR THE HIGHER ELEVATIONS OF THE WEST...BUT AT THIS TIME IT LOOKS TO
REMAIN SUB-ADVISORY. AS FOR SUNDAY...BOTH MODELS TAKE MOST OF THE
ENERGY TO THE NORTH AS THE SYSTEM BUMPS INTO THE RIDGE TO THE EAST.
THE CURRENT FORECAST WITH HIGHER POPS LOOKED REASONABLE AS A RESULT.
THE BIG CHANGE STILL LOOKS TO BE TEMPERATURES WITH HIGHS 10 TO 20
DEGREES COLDER THAN ON SATURDAY.

BY MONDAY...THIS ENERGY WILL MOVE AWAY TO THE EAST. HOWEVER...THE
TROUGH AXIS WILL STILL BE OVER THE AREA. IN ADDITION...THE MODELS
SHOW ANOTHER PIECE OF ENERGY MOVING UP FROM THE SOUTH THAT COULD
BRING A FEW SHOWERS...ESPECIALLY TO THE SOUTH. THE MODELS ARE
DISAGREEING ON TIMING...SO FAR NOW WE MADE FEW CHANGES. THERE ARE
ALSO DIFFERENCES FROM TUESDAY AND ONWARD...THE GFS HAS A FLATTER
FLOW WITH ANOTHER SHORTWAVE MOVING INTO WYOMING FOR TUESDAY.
MEANWHILE...THE EUROPEAN HAS A STRONGER RIDGE AND KEEPS THE AREA
WARMER AND DRIER. ONLY TIME WILL TELL WHAT WILL HAPPEN AT THAT POINT.

&&

.AVIATION.../00Z DISCUSSION/

PERIODS OF GUSTY WIND WILL CONTINUE THROUGH THE EARLY EVENING
HOURS...ESPECIALLY BETWEEN KRKS AND KCPR. IN ADDITION...SOME
LINGERING SHOWERS WILL REMAIN THROUGH 12Z THURSDAY...MAINLY OVER THE
HIGHER TERRAIN. THIS ACTIVITY MAY RESULT IN PERIODS OF INCREASED
TURBULENCE AND ICING OVER MOUNTAIN PASSES. AFTER 12Z THURSDAY...A
RIDGE OF HIGH PRESSURE WILL BUILD IN WITH WIDESPREAD DRY CONDITIONS.
OVERALL...VFR CONDITIONS ARE EXPECTED AT TERMINALS THROUGH THURSDAY
AFTERNOON.

&&

.FIRE WEATHER...

A WEAK WAVE OF LOW PRESSURE WILL KEEP SOME ISOLATED...GENERALLY
MOUNTAIN RELATED SHOWER ACTIVITY ACROSS WESTERN AND CENTRAL WYOMING
THROUGH THIS EVENING. AS THE SYSTEM COMPLETES ITS TRAVEL THROUGH THE
FORECAST AREA...AN AREA OF HIGH PRESSURE WILL BUILD IN BEHIND IT
BRINGING BENIGN CONDITIONS FOR THURSDAY. THIS RIDGE OF HIGH PRESSURE
IS EXPECTED TO LAST THROUGH SATURDAY MORNING. THE NEXT POTENTIAL
ROUND OF PRECIPITATION MAY BE FOUND BEGINNING SATURDAY AFTERNOON AS
AN AREA OF LOW PRESSURE APPROACHES WESTERN WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BRANHAM
LONG TERM...HATTINGS
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM







000
FXUS65 KRIW 291734
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1134 AM MDT WED OCT 29 2014

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
AN OPENING FAST MOVING TROUGH OVER THE PAC NW WILL SWIFTLY TRACK
EAST SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND KEEP THE
GRADIENT TIGHT ENOUGH FOR BREEZY CONDITIONS OVER WYOMING TODAY. NO
HIGH WIND IS EXPECTED WITH THE LACK OF ANY MTN WAVE SIGNATURE... JET
DYNAMICS...STRONG GRADIENT AT THE SFC AND H7 AND ANY SIGNIFICANT
TEMP GRADIENT. 20 TO 30 MPH WINDS WILL BE FAIRLY COMMON ALONG THE
SOUTHERN WIND CORRIDOR AND THE HIGHER ELEVATIONS TODAY. JUST SOME LIGHT
UPSLOPE INDUCED RAIN AND SNOW SHOWERS ARE EXPECTED IN FAR WESTERN WY
TODAY WITH ANY LIGHT SNOW FALLING ABOVE 7500 FEET.

AFTER THIS FAST MOVING TROUGHPA...A RIDGE WILL BUILD IN FROM THE
WEST WITH CONFLUENT FLOW AND MORE ULTRA CRISP DRY FALL WEATHER
EXPECTED THROUGH FRIDAY. ON FRIDAY...THE TROUGH NOW ASSOCIATED WITH
THE CIRCULATION NOW IN THE GULF OF ALASKA WILL MAKE LANDFALL WITH
THE GFS INDICATING A CLOSED CIRCULATION WITHIN THE TROUGH OFF THE
NORTHERN CALIFORNIA COAST. THE INCREASING SSW FLOW AHEAD OF THIS
APPROACHING TROUGH WOULD RESULT IN INCREASING CLOUDS AND MAYBE AN
ISOLATED RAIN OR SNOW SHOWER OR TWO BY LATE FRIDAY NIGHT IN THE FAR
WEST.

TEMPS WILL BE A LITTLE COOLER THU THAN TODAY EAST OF THE DIVIDE
BEHIND TODAYS TROUGH. ANOTHER MILD DAY WITH ABOVE NORMAL TEMPS ARE
EXPECTED ON HALLOWEEN ALONG WITH INCREASING BREEZES...OVERALL ONE OF
OUR FINER EVENINGS FOR TRICK OR TREATING.

.LONG TERM...SATURDAY THROUGH WEDNESDAY

MEDIUM RANGE PERIOD STARTS UP WITH A STRONG RIDGE OVER THE PLAINS
STATES WITH TROUGHS ON THE WEST COAST AND IN THE EAST. SIGNIFICANT
DIFFERENCES WITH OUR WEEKEND STORM SYSTEM AGAIN TONIGHT. THE GFS AND
ECMWF BOTH GENERALLY HAVE SIMILAR MOVEMENT INTO SATURDAY MORNING
WITH THE UPPER LOW MOVING INTO NRN NV BUT AFTER THAT THE GFS MOVES
THE SYSTEM ENE RIGHT INTO THE BIG RIDGE OVER THE PLAINS. THE ECMWF
SLIDES THE LOW MORE NE NEVER ACTUALLY TAKING THE UPPER LOW INTO
WYOMING. BY MIDDAY SUNDAY THE ECMWF HAS THE UPPER LOW OVER NCNTRL MT
WHILE THE GFS IS OVER ERN FREMONT COUNTY. WITH THE STRENGTH OF THE
RIDGE TO THE EAST...IT SEEMS UNLIKELY THAT THE UPPER LOW WILL MOVE
THAT FAR EAST INTO THE RIDGE. LEANED TOWARDS THE ECMWF AS MUCH AS I
COULD FOR NOW. STILL A DECENT SHOT OF SHOWERS AND A FEW
THUNDERSTORMS MOVING INTO THE SW LATE SATURDAY AND THEN SNOW SHOWERS
STILL FAIRLY LIKELY IN THE WEST SATURDAY NIGHT AND ACROSS THE WRN
AND NRN MOUNTAINS SUNDAY. NUDGED TEMPERATURES UP SOME OVER THE
WEEKEND WITH THIS EXPECTED TRACK. RIDGE TO THE SW GRADUALLY REBUILDS
BACK IN THE REMAINDER OF THE PERIOD WITH WARM TEMPERATURES.
TEMPERATURES SHOULD BE ABOVE NORMAL AGAIN BY WEDNESDAY WITH
POTENTIAL FOR 60S EAST OF THE DIVIDE WITH UPPER 40S AND 50S WEST.
WARMED TEMPERATURES AT THE END OF THE PERIOD BUT NOT AS MUCH AS IT
COULD BE IF TRENDS CONTINUE.

&&

.AVIATION.../18Z ISSUANCE/

ISOLATED SHOWERS WILL REMAIN POSSIBLE OVER THE NORTHERN MOUNTAINS
THROUGH 12Z THURSDAY. THESE CONDITIONS MAY BRING INCREASED
TURBULENCE AND ICING OVER IMPACTED AVIATION PASSES...WITH LITTLE
TO NO IMPACT EXPECTED AT TERMINALS. PERIODS OF GUSTY WIND WILL
REMAIN ACROSS THE AREA THROUGH AROUND 02Z THIS EVENING...WITH
ACTIVITY THEN WEAKENING. OVERALL...VFR CONDITIONS ARE EXPECTED AT
AREA TERMINALS.

&&

.FIRE WEATHER...
AN APPROACHING WEAK WAVE OF LOW PRESSURE MAY GENERATE SOME SHOWER
ACTIVITY OVER THE NORTHERN MOUNTAINS THIS MORNING WHICH MAY
CONTINUE AND INCREASE IN COVERAGE THROUGH THE AFTERNOON.
TEMPERATURES OVERALL WILL CONTINUE TO WARM ACROSS THE FORECAST
AREA...WITH SOME INCREASED AFTERNOON WIND.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...BRANHAM
FIRE WEATHER...LIPSON







000
FXUS65 KRIW 290854
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
254 AM MDT WED OCT 29 2014

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
AN OPENING FAST MOVING TROUGH OVER THE PAC NW WILL SWIFTLY TRACK
EAST SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND KEEP THE
GRADIENT TIGHT ENOUGH FOR BREEZY CONDITIONS OVER WYOMING TODAY. NO
HIGH WIND IS EXPECTED WITH THE LACK OF ANY MTN WAVE SIGNATURE... JET
DYNAMICS...STRONG GRADIENT AT THE SFC AND H7 AND ANY SIGNIFICANT
TEMP GRADIENT. 20 TO 30 MPH WINDS WILL BE FAIRLY COMMON ALONG THE
SOUTHERN WIND CORRIDOR AND THE HIGHER ELEVATIONS TODAY. JUST SOME LIGHT
UPSLOPE INDUCED RAIN AND SNOW SHOWERS ARE EXPECTED IN FAR WESTERN WY
TODAY WITH ANY LIGHT SNOW FALLING ABOVE 7500 FEET.

AFTER THIS FAST MOVING TROUGHPA...A RIDGE WILL BUILD IN FROM THE
WEST WITH CONFLUENT FLOW AND MORE ULTRA CRISP DRY FALL WEATHER
EXPECTED THROUGH FRIDAY. ON FRIDAY...THE TROUGH NOW ASSOCIATED WITH
THE CIRCULATION NOW IN THE GULF OF ALASKA WILL MAKE LANDFALL WITH
THE GFS INDICATING A CLOSED CIRCULATION WITHIN THE TROUGH OFF THE
NORTHERN CALIFORNIA COAST. THE INCREASING SSW FLOW AHEAD OF THIS
APPROACHING TROUGH WOULD RESULT IN INCREASING CLOUDS AND MAYBE AN
ISOLATED RAIN OR SNOW SHOWER OR TWO BY LATE FRIDAY NIGHT IN THE FAR
WEST.

TEMPS WILL BE A LITTLE COOLER THU THAN TODAY EAST OF THE DIVIDE
BEHIND TODAYS TROUGH. ANOTHER MILD DAY WITH ABOVE NORMAL TEMPS ARE
EXPECTED ON HALLOWEEN ALONG WITH INCREASING BREEZES...OVERALL ONE OF
OUR FINER EVENINGS FOR TRICK OR TREATING.

.LONG TERM...SATURDAY THROUGH WEDNESDAY

MEDIUM RANGE PERIOD STARTS UP WITH A STRONG RIDGE OVER THE PLAINS
STATES WITH TROUGHS ON THE WEST COAST AND IN THE EAST. SIGNIFICANT
DIFFERENCES WITH OUR WEEKEND STORM SYSTEM AGAIN TONIGHT. THE GFS AND
ECMWF BOTH GENERALLY HAVE SIMILAR MOVEMENT INTO SATURDAY MORNING
WITH THE UPPER LOW MOVING INTO NRN NV BUT AFTER THAT THE GFS MOVES
THE SYSTEM ENE RIGHT INTO THE BIG RIDGE OVER THE PLAINS. THE ECMWF
SLIDES THE LOW MORE NE NEVER ACTUALLY TAKING THE UPPER LOW INTO
WYOMING. BY MIDDAY SUNDAY THE ECMWF HAS THE UPPER LOW OVER NCNTRL MT
WHILE THE GFS IS OVER ERN FREMONT COUNTY. WITH THE STRENGTH OF THE
RIDGE TO THE EAST...IT SEEMS UNLIKELY THAT THE UPPER LOW WILL MOVE
THAT FAR EAST INTO THE RIDGE. LEANED TOWARDS THE ECMWF AS MUCH AS I
COULD FOR NOW. STILL A DECENT SHOT OF SHOWERS AND A FEW
THUNDERSTORMS MOVING INTO THE SW LATE SATURDAY AND THEN SNOW SHOWERS
STILL FAIRLY LIKELY IN THE WEST SATURDAY NIGHT AND ACROSS THE WRN
AND NRN MOUNTAINS SUNDAY. NUDGED TEMPERATURES UP SOME OVER THE
WEEKEND WITH THIS EXPECTED TRACK. RIDGE TO THE SW GRADUALLY REBUILDS
BACK IN THE REMAINDER OF THE PERIOD WITH WARM TEMPERATURES.
TEMPERATURES SHOULD BE ABOVE NORMAL AGAIN BY WEDNESDAY WITH
POTENTIAL FOR 60S EAST OF THE DIVIDE WITH UPPER 40S AND 50S WEST.
WARMED TEMPERATURES AT THE END OF THE PERIOD BUT NOT AS MUCH AS IT
COULD BE IF TRENDS CONTINUE.

&&

.AVIATION.../12Z ISSUANCE/
WEST OF THE DIVIDE KBPI/KJAC/KPNA/KRKS ROUTES

ISOLATED SNOW SHOWERS OVER NW WY MOUNTAINS THROUGH 12Z WITH LOCAL
MVFR CONDITIONS AND SOME MOUNTAIN OBSCURATION. OTHERWISE VFR
CONDITIONS WILL OCCUR THROUGH 12Z THROUGH TODAY.

EAST OF THE DIVIDE...KCPR/KCOD/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS WILL OCCUR THROUGH TODAY.


&&

.FIRE WEATHER...
AN APPROACHING WEAK WAVE OF LOW PRESSURE MAY GENERATE SOME SHOWER
ACTIVITY OVER THE NORTHERN MOUNTAINS THIS MORNING WHICH MAY
CONTINUE AND INCREASE IN COVERAGE THROUGH THE AFTERNOON.
TEMPERATURES OVERALL WILL CONTINUE TO WARM ACROSS THE FORECAST
AREA...WITH SOME INCREASED AFTERNOON WIND.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...SKRBAC
AVIATION...KPL
FIRE WEATHER...LIPSON











000
FXUS65 KRIW 290506
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1106 PM MDT TUE OCT 28 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

GENERALLY DRY CONDITIONS EXPECTED THIS EVENING ACROSS THE
AREA...WITH HIGH PRESSURE REMAINING. A WEAK WAVE OF LOW PRESSURE
WILL SWEEP THROUGH MONTANA...WITH ITS EDGE IMPACTING THE NORTHERN
PORTION OF THE STATE. THIS MAY BE ENOUGH TO GENERATE SOME ISOLATED
TO WIDELY SCATTERED SHOWERS OVER THE NORTHERN QUARTER OF THE
STATE...WITH MOST ACTIVITY EXPECTED TO REMAIN CONFINED TO THE
MOUNTAIN AREAS. SOME STRONG DOWNSLOPE WIND ACROSS THE FAVORED
LOCATIONS OF THE ABSAROKAS AND WIND RIVERS. STRONG WIND TO 50 MPH
WILL BE POSSIBLE AT SOME LOCATIONS...BUT WIND OVERALL IS EXPECTED TO
REMAIN BELOW HIGH WIND CRITERIA.

THIS WAVE OF LOW PRESSURE WILL DIVE THROUGH THE EASTERN HALF OF THE
STATE WEDNESDAY AFTERNOON...BRINGING INCREASED CLOUD COVER BUT IS
NOT EXPECTED TO RESULT IN ANY SHOWER ACTIVITY. HOWEVER...COVERAGE
MAY INCREASE SLIGHTLY ACROSS THE NORTHERN MOUNTAINS AND THE BIG HORN
BASIN. EXPECT TEMPERATURES TO CONTINUE TO WARM WEDNESDAY...WITH A
RETURN OF GUSTY WIND DURING THE AFTERNOON HOURS...ESPECIALLY ACROSS
THE WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

THE SYSTEM THAT BROUGHT THE SHOWERS ON WEDNESDAY ACROSS THE NORTH
LOOKS TO EXIT STAGE EAST ON WEDNESDAY NIGHT. WITH LINGERING UPSLOPE
FLOW THERE WILL STILL BE A FEW MOUNTAIN SHOWERS THROUGH THE EVENING
ALTHOUGH AMOUNTS LOOK TO BE INSIGNIFICANT. OTHER PERIOD OF QUIET
WEATHER WILL THEN MOVE IN FOR THURSDAY INTO FRIDAY AS RIDGING BUILDS
ACROSS THE AREA. A SYSTEM APPROACHING FROM THE WEST WILL TIGHTEN THE
PRESSURE GRADIENT A BIT FRIDAY AFTERNOON AND BRING A GUSTY WIND TO
THE FAVORED LOCATIONS IN SOUTHWESTERLY FLOW SUCH AS FROM ROCK
SPRINGS NORTHEASTWARD THROUGH NATRONA AND SOUTHERN JOHNSON COUNTIES.
MUCH OF THE REST OF THE COUNTRY WOULD CALL THIS WINDY...BUT IN
WYOMING WE CALL IT FRIDAY. THE NEXT DECENT WEATHER MAKER THEN LOOKS
TO BE MOVE IN FOR SATURDAY. BOTH THE GFS AND EUROPEAN HAVE SLOWED
THE PROGRESS OF THE STORM SO WE HAVE REMOVED PRECIPITATION FOR
SATURDAY MORNING. PRECIPITATION WILL SPREAD ACROSS AREAS WEST OF THE
DIVIDE THOUGH FOR SATURDAY AFTERNOON AS BETTER FORCING MOVES IN FROM
THE WEST. MEANWHILE...WITH THE PRESSURE GRADIENT CONTINUING TO
TIGHTEN EXPECT A WINDY DAY ACROSS AREAS EAST OF THE DIVIDE. THE
MODELS ARE SPLIT WITH THE EUROPEAN HAVING 50 KNOT WINDS AT 700
MILLIBARS WHILE THE GFS AS 40 TO 45 KNOTS. SO...THINGS WILL HAVE TO
BE WATCHED FOR HIGH WIND HIGHLIGHTS...ESPECIALLY IN AREAS FROM ROCK
SPRINGS TO CASPER. AT THE SAME TIME...THE STRONG DOWNSLOPING FLOW
WILL BRING WARM TEMPERATURES TO THE AREA WITH HIGH TEMPERATURES
POSSIBLY APPROACHING 70 IN SOME OF THE WARMER SPOTS IN THE EAST.
THIS DOWNSLOPING FLOW SHOULD KEEP AREAS EAST OF THE DIVIDE DRY
THROUGH MOST OF THE AFTERNOON. THE NEXT CONCERN IS POTENTIAL
SNOWFALL AMOUNTS...ESPECIALLY IN THE MOUNTAINS. BOTH THE GFS HAVE
SIMILAR TIMING WITH THE BEST DYNAMICS MOVING INTO NORTHERN WYOMING
FOR SATURDAY NIGHT BEFORE DEPARTING INTO MONTANA ON SUNDAY MORNING.
THE EUROPEAN REMAINS THE MORE MOIST MODEL ALTHOUGH IT HAS BACKED OFF
ON QPF JUST A BIT AS COMPARED TO THE 00Z RUN. THE PRECIPITATION AND
SNOWFALL AMOUNTS LOOKED REASONABLE AT THIS POINT SO WE MADE FEW
CHANGES. UNSETTLED WEATHER LOOKS TO BE THE RULE ACROSS THE AREA FOR
SUNDAY. MOST OF THE UPPER LEVEL FORCING WILL MOVE AWAY.
HOWEVER...WITH A TROUGH AXIS REMAINING OVER THE AREA AND
COOL...MOIST CYCLONIC CURVATURE AROUND SHOWS WILL PERSIST ON SUNDAY.
THE RESULT WILL BE THE 3C`S...CLOUDY...COOL AND CRUMMY. THE MODELS
THEN DIVERGE A BIT FOR MONDAY AND TUESDAY WITH DIFFERENT TIMING ON
SHORTWAVES. AS A RESULT...WE WENT WITH MAINLY SLIGHT CHANCE TO
CHANCE POPS ACROSS THE WESTERN MOUNTAINS WITH FAVORED OROGRAPHIC
FLOW AND MAINLY DRY EAST OF THE DIVIDE.

&&

.AVIATION.../06Z DISCUSSION/

MOSTLY CLEAR SKY DOMINATES FOR THE REST OF TONIGHT. THE FEATURE TO
WATCH WILL BE INCREASING SURFACE WIND DURING THE DAY WEDNESDAY
ACROSS WEST CENTRAL WYOMING. HIGH WIND IS POSSIBLE OVER THE HIGHER
TERRAIN EARLY...SPREADING ACROSS THE LOWER ELEVATIONS BY AFTERNOON WITH
A TIGHTENING PRESSURE GRADIENT. STRONGER MOUNTAIN RELATED WIND IS EXPECTED
NEAR THE TERMINALS OF KCOD AND KLND BY THIS TIME. OTHERWISE...VFR
CONDITIONS TO PREVAIL THROUGHOUT THE FORECAST PERIOD.

&&

.FIRE WEATHER...

GENERALLY DRY CONDITIONS ARE ANTICIPATED DURING THE EARLY EVENING
HOURS TONIGHT. AN APPROACHING WEAK WAVE OF LOW PRESSURE MAY GENERATE
SOME SHOWER ACTIVITY OVER THE NORTHERN MOUNTAINS AFTER 0300
TONIGHT...WHICH MAY CONTINUE AND INCREASE IN COVERAGE THROUGH
THE AFTERNOON. TEMPERATURES OVERALL WILL CONTINUE TO WARM
ACROSS THE FORECAST AREA...WITH SOME INCREASED AFTERNOON WIND.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM...BRANHAM
LONG TERM...HATTINGS
AVIATION...KPL
FIRE WEATHER...BRANHAM






000
FXUS65 KRIW 282124
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
324 PM MDT TUE OCT 28 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

GENERALLY DRY CONDITIONS EXPECTED THIS EVENING ACROSS THE
AREA...WITH HIGH PRESSURE REMAINING. A WEAK WAVE OF LOW PRESSURE
WILL SWEEP THROUGH MONTANA...WITH ITS EDGE IMPACTING THE NORTHERN
PORTION OF THE STATE. THIS MAY BE ENOUGH TO GENERATE SOME ISOLATED
TO WIDELY SCATTERED SHOWERS OVER THE NORTHERN QUARTER OF THE
STATE...WITH MOST ACTIVITY EXPECTED TO REMAIN CONFINED TO THE
MOUNTAIN AREAS. SOME STRONG DOWNSLOPE WIND ACROSS THE FAVORED
LOCATIONS OF THE ABSAROKAS AND WIND RIVERS. STRONG WIND TO 50 MPH
WILL BE POSSIBLE AT SOME LOCATIONS...BUT WIND OVERALL IS EXPECTED TO
REMAIN BELOW HIGH WIND CRITERIA.

THIS WAVE OF LOW PRESSURE WILL DIVE THROUGH THE EASTERN HALF OF THE
STATE WEDNESDAY AFTERNOON...BRINGING INCREASED CLOUD COVER BUT IS
NOT EXPECTED TO RESULT IN ANY SHOWER ACTIVITY. HOWEVER...COVERAGE
MAY INCREASE SLIGHTLY ACROSS THE NORTHERN MOUNTAINS AND THE BIG HORN
BASIN. EXPECT TEMPERATURES TO CONTINUE TO WARM WEDNESDAY...WITH A
RETURN OF GUSTY WIND DURING THE AFTERNOON HOURS...ESPECIALLY ACROSS
THE WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

THE SYSTEM THAT BROUGHT THE SHOWERS ON WEDNESDAY ACROSS THE NORTH
LOOKS TO EXIT STAGE EAST ON WEDNESDAY NIGHT. WITH LINGERING UPSLOPE
FLOW THERE WILL STILL BE A FEW MOUNTAIN SHOWERS THROUGH THE EVENING
ALTHOUGH AMOUNTS LOOK TO BE INSIGNIFICANT. OTHER PERIOD OF QUIET
WEATHER WILL THEN MOVE IN FOR THURSDAY INTO FRIDAY AS RIDGING BUILDS
ACROSS THE AREA. A SYSTEM APPROACHING FROM THE WEST WILL TIGHTEN THE
PRESSURE GRADIENT A BIT FRIDAY AFTERNOON AND BRING A GUSTY WIND TO
THE FAVORED LOCATIONS IN SOUTHWESTERLY FLOW SUCH AS FROM ROCK
SPRINGS NORTHEASTWARD THROUGH NATRONA AND SOUTHERN JOHNSON COUNTIES.
MUCH OF THE REST OF THE COUNTRY WOULD CALL THIS WINDY...BUT IN
WYOMING WE CALL IT FRIDAY. THE NEXT DECENT WEATHER MAKER THEN LOOKS
TO BE MOVE IN FOR SATURDAY. BOTH THE GFS AND EUROPEAN HAVE SLOWED
THE PROGRESS OF THE STORM SO WE HAVE REMOVED PRECIPITATION FOR
SATURDAY MORNING. PRECIPITATION WILL SPREAD ACROSS AREAS WEST OF THE
DIVIDE THOUGH FOR SATURDAY AFTERNOON AS BETTER FORCING MOVES IN FROM
THE WEST. MEANWHILE...WITH THE PRESSURE GRADIENT CONTINUING TO
TIGHTEN EXPECT A WINDY DAY ACROSS AREAS EAST OF THE DIVIDE. THE
MODELS ARE SPLIT WITH THE EUROPEAN HAVING 50 KNOT WINDS AT 700
MILLIBARS WHILE THE GFS AS 40 TO 45 KNOTS. SO...THINGS WILL HAVE TO
BE WATCHED FOR HIGH WIND HIGHLIGHTS...ESPECIALLY IN AREAS FROM ROCK
SPRINGS TO CASPER. AT THE SAME TIME...THE STRONG DOWNSLOPING FLOW
WILL BRING WARM TEMPERATURES TO THE AREA WITH HIGH TEMPERATURES
POSSIBLY APPROACHING 70 IN SOME OF THE WARMER SPOTS IN THE EAST.
THIS DOWNSLOPING FLOW SHOULD KEEP AREAS EAST OF THE DIVIDE DRY
THROUGH MOST OF THE AFTERNOON. THE NEXT CONCERN IS POTENTIAL
SNOWFALL AMOUNTS...ESPECIALLY IN THE MOUNTAINS. BOTH THE GFS HAVE
SIMILAR TIMING WITH THE BEST DYNAMICS MOVING INTO NORTHERN WYOMING
FOR SATURDAY NIGHT BEFORE DEPARTING INTO MONTANA ON SUNDAY MORNING.
THE EUROPEAN REMAINS THE MORE MOIST MODEL ALTHOUGH IT HAS BACKED OFF
ON QPF JUST A BIT AS COMPARED TO THE 00Z RUN. THE PRECIPITATION AND
SNOWFALL AMOUNTS LOOKED REASONABLE AT THIS POINT SO WE MADE FEW
CHANGES. UNSETTLED WEATHER LOOKS TO BE THE RULE ACROSS THE AREA FOR
SUNDAY. MOST OF THE UPPER LEVEL FORCING WILL MOVE AWAY.
HOWEVER...WITH A TROUGH AXIS REMAINING OVER THE AREA AND
COOL...MOIST CYCLONIC CURVATURE AROUND SHOWS WILL PERSIST ON SUNDAY.
THE RESULT WILL BE THE 3C`S...CLOUDY...COOL AND CRUMMY. THE MODELS
THEN DIVERGE A BIT FOR MONDAY AND TUESDAY WITH DIFFERENT TIMING ON
SHORTWAVES. AS A RESULT...WE WENT WITH MAINLY SLIGHT CHANCE TO
CHANCE POPS ACROSS THE WESTERN MOUNTAINS WITH FAVORED OROGRAPHIC
FLOW AND MAINLY DRY EAST OF THE DIVIDE.

&&

.AVIATION.../00Z DISCUSSION/

VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE FORECAST PERIOD.
A WEAK WAVE OF LOW PRESSURE WILL MOVE THROUGH NORTHERN WYOMING AFTER
03Z TONIGHT...POTENTIALLY GENERATING SOME WEAK SHOWER ACTIVITY. MOST
ACTIVITY WILL BE CONFINED TO THE HIGHER ELEVATIONS. THIS ACTIVITY
MAY HELP TO INCREASE TURBULENCE OR ICING OVER THE IMPACTED MOUNTAIN
PASSES.

STRONGER MOUNTAIN RELATED WIND IS EXPECTED OVERNIGHT NEAR THE
TERMINALS OF KCOD AND KLND. WHILE THE STRONGEST SURFACE WIND IS NOT
ANTICIPATED TO IMPACT EITHER OF THESE TERMINALS...SOME LLWS WILL BE
POSSIBLE BETWEEN 06Z AND 15Z WEDNESDAY. A RETURN OF GUSTY WIND AFTER
17Z WILL BE POSSIBLE AT MANY TERMINALS DUE TO THE PASSAGE OF THE
WEAK WAVE OF LOW PRESSURE.

&&

.FIRE WEATHER...

GENERALLY DRY CONDITIONS ARE ANTICIPATED DURING THE EARLY EVENING
HOURS TONIGHT. AN APPROACHING WEAK WAVE OF LOW PRESSURE MAY GENERATE
SOME SHOWER ACTIVITY OVER THE NORTHERN MOUNTAINS AFTER 0300
TONIGHT...WHICH MAY CONTINUE AND INCREASE IN COVERAGE THROUGH
THE AFTERNOON. TEMPERATURES OVERALL WILL CONTINUE TO WARM
ACROSS THE FORECAST AREA...WITH SOME INCREASED AFTERNOON WIND.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BRANHAM
LONG TERM...HATTINGS
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM







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