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000
FXUS65 KRIW 222058
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
258 PM MDT WED OCT 22 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY

A DRY STABLE CONFLUENT FLOW HAS ENSUED OVER THE AREA AS TUESDAYS
TROUGH EXITS THE AREA AND A FLATTENING RIDGE MOVES IN FROM THE
WEST. THE TREND THROUGH THU WILL BE FOR INCREASING WESTERLY FLOW
AS THE GRADIENT TIGHTENS WITH THE FLATTENING RIDGE AND THE CLOSED
LOW OVER THE GULF OF ALASKA CHURNS OUT ANOTHER CLOSED LOW EAST
ACROSS CANADA AND SLINGS A VIGOROUS SHORTWAVE TOWARD THE NORTHERN
ROCKIES...AND AT THE SAME TIME A RIDGE BUILDS INTO THE SOUTHERN
ROCKIES FROM THE SOUTHWEST. INCREASING WEST WINDS WILL RESPOND TO
THIS SET UP... ESPECIALLY ALONG THE EAST SLOPE OF THE CONTINENTAL
DIVIDE AND ALONG THE SOUTHERN WIND CORRIDOR. IN ADDITION...WEST
WINDS WILL LIKELY INCREASE SIGNIFICANTLY IN THE AREA NORTH OF CODY
BY LATE THU AFTERNOON...PRIMARILY AROUND CLARK AS A POTENTIAL MTN
WAVE...ALBEIT RELATIVELY WEAK...DEVELOPS. A FROUDE NUMBER OF 1 BY
00Z FRI IN THAT AREA AS WELL AS A PROGGED CRITICAL LAYER ABOVE THE
ABSAROKA MTNS REFLECTS THIS NOTION. IN ADDITION...THE WEST
SOUTHWEST DIFLUENT FLOW WILL RESULT IN ISOLD RAIN/SNOW SHOWERS IN
THE FAR NW MTNS LATE THU. SOUTHWEST WEST WINDS HAVE ALREADY KICKED
IN ALONG THE SOUTHERN WIND CORRIDOR FROM THE GREEN MTNS TO KCPR.
OTHERWISE...EXPECT DRY WEATHER THROUGH THU. TEMPERATURES WILL BE
AROUND 10 DEGREES WARMER EVERYWHERE THU AS THE COOL AIR BEHIND
WEDNESDAYS TROUGH EXITS TO THE EAST.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

POTENTIAL MOUNTAIN WAVE EVENT TO START THIS PERIOD IN THE CODY
FOOTHILLS AS POTENTIALLY FAVORABLE MOUNTAIN TOP CONDITIONS COMBINE
WITH APPROACHING RIGHT FRONT QUAD OF 150KT+ UPPER JET AND MODERATE
GAP FLOW SIGNATURE. NAM12 IS PICKING UP A PERIOD OF UPSTREAM
MOUNTAIN TOP INVERSION AFTER MIDNIGHT THURSDAY NIGHT WHILE THE WRF
CROSS SECTION IS SHOWING A PERIOD IN THE EVENING THURSDAY OF
POTENTIAL FLOW REVERSAL OR AT LEAST POTENTIAL FOR WAVE INDUCED
CRITICAL LAYER. FROUDE CALCULATIONS FOR THURSDAY NIGHT ARE PRETTY
CONSISTENT IN THE 1 RANGE. WRF BOUNDARY LEVEL WINDS ARE NOT OVERLY
IMPRESSIVE ON THE FLATS BUT GET OVER 50KTS NEAR THE STEEP TERRAIN.
POTENTIAL IS GREAT ENOUGH TO AT LEAST GET THE WATCH OUT AS THERE ARE
ENOUGH FEATURES THAT COULD CAUSE THIS TO BE A DECENT EVENT. THE LOW
END WOULD PROBABLY PRODUCE NEAR OR AT HIGH WINDS FOR THE GAPS AND
WEST SIDE OF CLARK WHILE THE HIGH END WOULD RESULT IN A WAVE
BREAKING MOUNTAIN WAVE EVENT WITH WINDS WELL OVER 60 MPH WITH
POTENTIAL FOR 80 MPH PLUS. MOIST PLUME APPROACHES ABOUT THE SAME
TIME WITH OUR APPROACHING FRONTAL BOUNDARY WHICH WILL PROBABLY CLIP
THE NWRN CORNER WITH A LITTLE LIGHT PCPN THURSDAY NIGHT INTO FRIDAY
MORNING BEFORE RIDGING PUSHES IT NORTH INTO MT. SHALLOW FRONTAL
BOUNDARY STILL EXPECTED TO SIT ACROSS THE NORTH FRIDAY FOR A SLIGHT
TEMPERING OF TEMPERATURES COMPARED TO AREAS JUST TO THE SOUTH.
SATURDAY LOOKS WARM AND DRY WITH INCREASING SW WIND.

ERN PACIFIC TROUGH THEN OPENS UP AND MOVES INLAND ACROSS US SUNDAY
INTO MONDAY WITH MODELS VARYING ON TIMING AND STRENGTH OF SECONDARY
BACK SIDE SYSTEM SUNDAY NIGHT/MON MRNG. AIRMASS STILL LOOKS COLD
ENOUGH FOR POTENTIAL LIGHT SNOW IN CENTRAL WYO LATER SUNDAY NIGHT
INTO MONDAY MORNING WHERE PCPN FALLS. DECENT SHOT OF RAIN CHANGING
TO SNOW IN THE MOUNTAINS WITH THIS SYSTEM WITH A COUPLE TO SEVERAL
INCHES QUITE POSSIBLE IN THE MOUNTAINS. BRIEF RIDGING WITH
TEMPERATURES RECOVERING SOME TUESDAY BEFORE POTENTIAL SEWD MOVING
SHORTWAVE MOVES ACROSS LATER TUESDAY NIGHT INTO WEDNESDAY. MODELS
STRUGGLING WITH THE PATTERN CHANGE AND MOVEMENT OF SEVERAL KEY UPPER
LOWS OVER ASIA BUT IT DOES APPEAR THAT SIGNIFICANT CHANGES COULD BE
IN THE OFFING JUST BEYOND THE MEDIUM RANGE PERIOD. HOW IT ALL
EVOLVES AND THE EXACT TIMING IS STILL UNCERTAIN...MOST LIKELY
BETWEEN HALLOWEEN AND THE FIRST COUPLE DAYS OF NOVEMBER. NOTHING
CERTAIN YET.

&&

.AVIATION.../00Z ISSUANCE/
VFR CONDITIONS WILL OCCUR TONIGHT WITH MAINLY SKC SKIES. EXPECT
INCREASING MID/HIGH LEVEL CLOUDINESS AND STRENGTHENING MOUNTAIN
TOP WINDS WITH POSSIBLY SOME LLWS ON THE LEE SIDE OF MOUNTAIN
RANGES ALONG THE CONTINENTAL DIVIDE DEVELOPING AFTER 06Z TONIGHT. HOWEVER
NOT ENOUGH CONFIDENCE OR MAGNITUDE TO INCLUDE AT KCOD OR KLND AT
THIS TIME. WEST SOUTHWEST WINDS WILL INCREASE FROM KRKS TO KCPR BY
18Z THURSDAY. WEST WINDS WILL INCREASE FROM KCOD NORTH TO CLARK BY
00Z FRIDAY.

&&

.FIRE WEATHER...
TEMPERATURES REBOUND A BIT ON THURSDAY AS HIGH PRESSURE BUILDS IN FROM
THE SOUTH BUT IT WILL BE ANOTHER BREEZY DAY IN SPOTS WITH
SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN ROCK SPRINGS AND
CASPER AND OVER THE HIGHER ELEVATIONS. ON THURSDAY NIGHT WEST
WINDS WILL INCREASE SIGNIFICANTLY IN THE AREA AROUND CLARK NORTH
OF CODY.SOUTHWEST FLOW RETURNS ON FRIDAY WITH DRIER AND WARMER
CONDITIONS REMAINING. THERE COULD BE A FEW GUSTS OVER 25 MPH IN
THE AFTERNOON BETWEEN RAWLINS AND SOUTHERN CASPER DISPATCH BUT
MOST AREAS WILL HAVE RELATIVELY LIGHT WINDS.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
WYZ003.

&&

$$

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









000
FXUS65 KRIW 221830
AFDRIW

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE RIVERTON WY
1230 PM MDT WED OCT 22 2014

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT

A COOLER AIRMASS HANGING AROUND TODAY BEHIND THE COLD FRONT THAT
PASSED THROUGH OVERNIGHT WITH SOME MODERATION ON THURSDAY AND
FRIDAY. AFTER A RELATIVELY CALM DAY TODAY...THURSDAY IS EXPECTED TO
BE ANOTHER WINDY DAY AS A TUG OF WAR ENSUES BETWEEN THE COLD BUT
DYNAMIC TROUGH TO OUR NORTHWEST AND THE RIDGE POKING IN FROM THE
SOUTH. MODELS HAVE BEEN TRENDING FURTHER SOUTH WITH THE
STRENGTHENING JET TO OUR NORTHWEST ON THURSDAY...WHICH COULD
INTRODUCE STRONGER WINDS ACROSS THE NORTHERN MOUNTAINS AND A SLIGHT
CHANCE FOR PRECIPITATION. AS THE INFLUENCE OF THE RIGHT EXIT REGION
OF THE JET INTRUDES THURSDAY AFTERNOON THROUGH FRIDAY...THIS WILL
KICK UP THE MOUNTAIN WAVE POTENTIAL OVER THE ABSAROKAS...MAINTAINING
CONSISTENCY WITH THE DAY SHIFT FORECAST FOR SOME WIND GUSTS IN THE
WESTERN CODY FOOTHILLS AT 50 MPH FOR LATE THURSDAY OR THURSDAY NIGHT
INTO FRIDAY MORNING. ALSO BUMPED UP POPS A LITTLE FOR THE NORTHWEST
ON THURSDAY NIGHT AND FRIDAY AS A WAVE MOVES THROUGH. MOST OF THE
ACTION WILL REMAIN TO OUR WEST BUT THERE COULD BE A FEW SHOWERS
AROUND YELLOWSTONE AND THE TETONS. OTHERWISE WESTERN AND CENTRAL
WYOMING WILL BE DRY AND BREEZY THROUGH THE PERIOD WITH ABOVE NORMAL
TEMPERATURES.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
SYNOPSIS...UNSEASONABLY WARM AND BREEZY TO WINDY CONDITIONS WILL
PREVAIL ON SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE. A
COLD FRONT WILL PUSH ACROSS THE AREA SUNDAY AND SUNDAY NIGHT
SPREADING RAIN AND SNOW SHOWERS AND COLDER TEMPERATURES ACROSS THE
AREA INTO MONDAY. A WESTERLY FLOW WILL BRING MAINLY DRY AND
SEASONABLE MILD CONDITIONS ON TUESDAY AND WEDNESDAY.

DISCUSSION...COMPLEX VORTEX OVER THE GULF OF ALASKA THIS MORNING
WILL WOBBLE SE TO THE WEST COAST SATURDAY MORNING. MEDIUM RANGE
MODELS CONTINUE TO HANDLE THE INDIVIDUAL VORTICES WITHIN THIS
COMPLEX DIFFERENTLY...BUT AGREE THAT A VERY WARM SW FLOW WILL
PREVAIL OVER THE AREA SATURDAY BETWEEN THIS SYSTEM AND STRONG
DOWNSTREAM RIDGE OVER THE PLAINS. RECORD HIGH TERRITORY FOR THE
25TH IS GENERALLY 72-74F RANGE ACROSS CENTRAL WY FOR THE 25TH...A
BIT WARMER AT WRL AT 79F. FORECAST HIGHS ARE CURRENTLY NEAR OR
EXCEEDING THESE RECORDS.

ON THE 22/00Z GFS AND ECMWF RUNS...GFS CONTINUES TO EJECT LEAD
SHORTWAVE OUT OF BASE OF THE TROUGH NE INTO WESTERN MONTANA
SATURDAY NIGHT WHILE THE ECMWF SHOWS A MORE SPLIT
SYSTEM...SWINGING THIS SHORTWAVE FURTHER SOUTH ACROSS THE GREAT
BASIN SATURDAY NIGHT. GFS VERSION WOULD KEEP MOST OF THE
PRECIPITATION CONFINED TO THE WEST DURING THE DAY SUNDAY WITH
WINDY AND MILD CONDITIONS ACROSS THE CENTRAL AND SOUTH. ECMWF
DEPICTION WOULD RESULT IN MUCH COOLER AND WETTER CONDITIONS ACROSS
THE AREA SUNDAY. EC AND GFS ENSEMBLE MEANS FAVOR SLOWER
PROGRESSION...MORE RESPECT FOR STRONG PLAINS RIDGE.
HOWEVER...EITHER WAY MUCH COLDER AIR WILL SPILL INTO THE AREA
SUNDAY NIGHT BEHIND THE FRONT WITH SNOW LEVELS EXPECTED TO BE
BETWEEN 5-6KFT BY MONDAY MORNING. THE NORTHERN THIRD OF THE AREA
STANDS THE BEST CHANCE FOR SOME ACCUMULATION MONDAY
MORNING...MAINLY ON VEGETATION WITH WET ROADS BELOW 6KFT. COOL AND
UNSETTLED NW FLOW WILL PREVAIL ON THE BACK SIDE OF THE TROUGH
LATTER IN THE DAY MONDAY WITH THE BETTER MOISTURE AND INSTABILITY
EXPECTED OVER THE NE HALF OF THE CWA. ZONAL FLOW WILL DEVELOP
BEHIND THIS TROUGH TUESDAY AND WEDNESDAY...BRINGING IN MILDER
PACIFIC AIRMASS ALONG WITH SOME OROGRAPHIC PRECIPITATION IN THE
WEST.

&&

.AVIATION.../18Z ISSUANCE/

VFR CONDITIONS WILL OCCUR TODAY WITH MAINLY SKC SKIES AND LIGHT
WINDS. AFTER 00Z...EXPECT INCREASING MID/HIGH LEVEL CLOUDINESS AND
STRENGTHENING MOUNTAIN TOP WINDS WITH POSSIBLY SOME LLWS ON THE LEE
SIDE OF MOUNTAIN RANGES ALONG THE CONTINENTAL DIVIDE DEVELOPING
AFTER 06Z. HOWEVER NOT ENOUGH CONFIDENCE OR MAGNITUDE TO INCLUDE AT
KCOD OR KLND AT THIS TIME. WEST SOUTHWEST WINDS WILL INCREASE FROM
KRKS TO KCPR BY 18Z THURSDAY.

&&

.FIRE WEATHER...

THE WIND AND THE RAIN WILL CLEAR OUT TODAY WITH COOL TEMPERATURES
REMAINING BEHIND THE FRONT THAT PASSED THROUGH YESTERDAY.
TEMPERATURES REBOUND A BIT ON THURSDAY AS HIGH PRESSURE BUILDS IN
FROM THE SOUTH BUT IT WILL BE ANOTHER BREEZY DAY IN SPOTS WITH
SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN ROCK SPRINGS AND
CASPER AND OVER THE HIGHER ELEVATIONS. SOUTHWEST FLOW RETURNS ON
FRIDAY WITH DRIER AND WARMER CONDITIONS REMAINING. THERE COULD BE A
FEW GUSTS OVER 25 MPH IN THE AFTERNOON BETWEEN RAWLINS AND SOUTHERN
CASPER DISPATCH BUT MOST AREAS WILL HAVE RELATIVELY LIGHT WINDS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...WM/LIPSON
FIRE WEATHER...ALLEN














000
FXUS65 KRIW 220937
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
337 AM MDT WED OCT 22 2014

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT

A COOLER AIRMASS HANGING AROUND TODAY BEHIND THE COLD FRONT THAT
PASSED THROUGH OVERNIGHT WITH SOME MODERATION ON THURSDAY AND
FRIDAY. AFTER A RELATIVELY CALM DAY TODAY...THURSDAY IS EXPECTED TO
BE ANOTHER WINDY DAY AS A TUG OF WAR ENSUES BETWEEN THE COLD BUT
DYNAMIC TROUGH TO OUR NORTHWEST AND THE RIDGE POKING IN FROM THE
SOUTH. MODELS HAVE BEEN TRENDING FURTHER SOUTH WITH THE
STRENGTHENING JET TO OUR NORTHWEST ON THURSDAY...WHICH COULD
INTRODUCE STRONGER WINDS ACROSS THE NORTHERN MOUNTAINS AND A SLIGHT
CHANCE FOR PRECIPITATION. AS THE INFLUENCE OF THE RIGHT EXIT REGION
OF THE JET INTRUDES THURSDAY AFTERNOON THROUGH FRIDAY...THIS WILL
KICK UP THE MOUNTAIN WAVE POTENTIAL OVER THE ABSAROKAS...MAINTAINING
CONSISTENCY WITH THE DAY SHIFT FORECAST FOR SOME WIND GUSTS IN THE
WESTERN CODY FOOTHILLS AT 50 MPH FOR LATE THURSDAY OR THURSDAY NIGHT
INTO FRIDAY MORNING. ALSO BUMPED UP POPS A LITTLE FOR THE NORTHWEST
ON THURSDAY NIGHT AND FRIDAY AS A WAVE MOVES THROUGH. MOST OF THE
ACTION WILL REMAIN TO OUR WEST BUT THERE COULD BE A FEW SHOWERS
AROUND YELLOWSTONE AND THE TETONS. OTHERWISE WESTERN AND CENTRAL
WYOMING WILL BE DRY AND BREEZY THROUGH THE PERIOD WITH ABOVE NORMAL
TEMPERATURES.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
SYNOPSIS...UNSEASONABLY WARM AND BREEZY TO WINDY CONDITIONS WILL
PREVAIL ON SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE. A
COLD FRONT WILL PUSH ACROSS THE AREA SUNDAY AND SUNDAY NIGHT
SPREADING RAIN AND SNOW SHOWERS AND COLDER TEMPERATURES ACROSS THE
AREA INTO MONDAY. A WESTERLY FLOW WILL BRING MAINLY DRY AND
SEASONABLE MILD CONDITIONS ON TUESDAY AND WEDNESDAY.

DISCUSSION...COMPLEX VORTEX OVER THE GULF OF ALASKA THIS MORNING
WILL WOBBLE SE TO THE WEST COAST SATURDAY MORNING. MEDIUM RANGE
MODELS CONTINUE TO HANDLE THE INDIVIDUAL VORTICES WITHIN THIS
COMPLEX DIFFERENTLY...BUT AGREE THAT A VERY WARM SW FLOW WILL
PREVAIL OVER THE AREA SATURDAY BETWEEN THIS SYSTEM AND STRONG
DOWNSTREAM RIDGE OVER THE PLAINS. RECORD HIGH TERRITORY FOR THE
25TH IS GENERALLY 72-74F RANGE ACROSS CENTRAL WY FOR THE 25TH...A
BIT WARMER AT WRL AT 79F. FORECAST HIGHS ARE CURRENTLY NEAR OR
EXCEEDING THESE RECORDS.

ON THE 22/00Z GFS AND ECMWF RUNS...GFS CONTINUES TO EJECT LEAD
SHORTWAVE OUT OF BASE OF THE TROUGH NE INTO WESTERN MONTANA
SATURDAY NIGHT WHILE THE ECMWF SHOWS A MORE SPLIT
SYSTEM...SWINGING THIS SHORTWAVE FURTHER SOUTH ACROSS THE GREAT
BASIN SATURDAY NIGHT. GFS VERSION WOULD KEEP MOST OF THE
PRECIPITATION CONFINED TO THE WEST DURING THE DAY SUNDAY WITH
WINDY AND MILD CONDITIONS ACROSS THE CENTRAL AND SOUTH. ECMWF
DEPICTION WOULD RESULT IN MUCH COOLER AND WETTER CONDITIONS ACROSS
THE AREA SUNDAY. EC AND GFS ENSEMBLE MEANS FAVOR SLOWER
PROGRESSION...MORE RESPECT FOR STRONG PLAINS RIDGE.
HOWEVER...EITHER WAY MUCH COLDER AIR WILL SPILL INTO THE AREA
SUNDAY NIGHT BEHIND THE FRONT WITH SNOW LEVELS EXPECTED TO BE
BETWEEN 5-6KFT BY MONDAY MORNING. THE NORTHERN THIRD OF THE AREA
STANDS THE BEST CHANCE FOR SOME ACCUMULATION MONDAY
MORNING...MAINLY ON VEGETATION WITH WET ROADS BELOW 6KFT. COOL AND
UNSETTLED NW FLOW WILL PREVAIL ON THE BACK SIDE OF THE TROUGH
LATTER IN THE DAY MONDAY WITH THE BETTER MOISTURE AND INSTABILITY
EXPECTED OVER THE NE HALF OF THE CWA. ZONAL FLOW WILL DEVELOP
BEHIND THIS TROUGH TUESDAY AND WEDNESDAY...BRINGING IN MILDER
PACIFIC AIRMASS ALONG WITH SOME OROGRAPHIC PRECIPITATION IN THE
WEST.

&&

.AVIATION.../12Z ISSUANCE/

LOW CLOUDS /020-050 KFT AGL/ AND POSSIBLY SOME PATCHY FOG ACROSS
NORTHWEST WYOMING /NW OF A KAFO-KPNA-30W KCOD LINE/ THIS MORNING
WILL BE THE MAIN AVIATION HAZARD FOR THIS SET OF TAFS. THIS WOULD
PRIMARILY IMPACT THE KJAC TERMINAL...WITH CEILINGS AT KJAC PROBABLY
HIGH MVFR TO LOW VFR. FOG CHANCES AT KJAC WILL BE SLIM DUE TO THE
AFOREMENTIONED STRATCU DECK. THIS FOG/LOW CLOUDS ACROSS THE
NORTHWEST ARE EXPECTED TO ERODE BY AROUND 18Z. OTHERWISE...VFR
CONDITIONS WILL OCCUR TODAY WITH MAINLY SKC SKIES AND LIGHT WINDS.
AFTER 00Z...EXPECT INCREASING MID/HIGH LEVEL CLOUDINESS AND
STRENGTHENING MOUNTAIN TOP WINDS WITH POSSIBLY SOME LLWS ON THE LEE
SIDE OF MOUNTAIN RANGES ALONG THE CONTINENTAL DIVIDE DEVELOPING
AFTER 06Z. HOWEVER NOT ENOUGH CONFIDENCE OR MAGNITUDE TO INCLUDE AT
KCOD OR KLND AT THIS TIME.

&&

.FIRE WEATHER...

THE WIND AND THE RAIN WILL CLEAR OUT TODAY WITH COOL TEMPERATURES
REMAINING BEHIND THE FRONT THAT PASSED THROUGH YESTERDAY.
TEMPERATURES REBOUND A BIT ON THURSDAY AS HIGH PRESSURE BUILDS IN
FROM THE SOUTH BUT IT WILL BE ANOTHER BREEZY DAY IN SPOTS WITH
SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN ROCK SPRINGS AND
CASPER AND OVER THE HIGHER ELEVATIONS. SOUTHWEST FLOW RETURNS ON
FRIDAY WITH DRIER AND WARMER CONDITIONS REMAINING. THERE COULD BE A
FEW GUSTS OVER 25 MPH IN THE AFTERNOON BETWEEN RAWLINS AND SOUTHERN
CASPER DISPATCH BUT MOST AREAS WILL HAVE RELATIVELY LIGHT WINDS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...WM
FIRE WEATHER...ALLEN











000
FXUS65 KRIW 220937
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
337 AM MDT WED OCT 22 2014

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT

A COOLER AIRMASS HANGING AROUND TODAY BEHIND THE COLD FRONT THAT
PASSED THROUGH OVERNIGHT WITH SOME MODERATION ON THURSDAY AND
FRIDAY. AFTER A RELATIVELY CALM DAY TODAY...THURSDAY IS EXPECTED TO
BE ANOTHER WINDY DAY AS A TUG OF WAR ENSUES BETWEEN THE COLD BUT
DYNAMIC TROUGH TO OUR NORTHWEST AND THE RIDGE POKING IN FROM THE
SOUTH. MODELS HAVE BEEN TRENDING FURTHER SOUTH WITH THE
STRENGTHENING JET TO OUR NORTHWEST ON THURSDAY...WHICH COULD
INTRODUCE STRONGER WINDS ACROSS THE NORTHERN MOUNTAINS AND A SLIGHT
CHANCE FOR PRECIPITATION. AS THE INFLUENCE OF THE RIGHT EXIT REGION
OF THE JET INTRUDES THURSDAY AFTERNOON THROUGH FRIDAY...THIS WILL
KICK UP THE MOUNTAIN WAVE POTENTIAL OVER THE ABSAROKAS...MAINTAINING
CONSISTENCY WITH THE DAY SHIFT FORECAST FOR SOME WIND GUSTS IN THE
WESTERN CODY FOOTHILLS AT 50 MPH FOR LATE THURSDAY OR THURSDAY NIGHT
INTO FRIDAY MORNING. ALSO BUMPED UP POPS A LITTLE FOR THE NORTHWEST
ON THURSDAY NIGHT AND FRIDAY AS A WAVE MOVES THROUGH. MOST OF THE
ACTION WILL REMAIN TO OUR WEST BUT THERE COULD BE A FEW SHOWERS
AROUND YELLOWSTONE AND THE TETONS. OTHERWISE WESTERN AND CENTRAL
WYOMING WILL BE DRY AND BREEZY THROUGH THE PERIOD WITH ABOVE NORMAL
TEMPERATURES.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
SYNOPSIS...UNSEASONABLY WARM AND BREEZY TO WINDY CONDITIONS WILL
PREVAIL ON SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE. A
COLD FRONT WILL PUSH ACROSS THE AREA SUNDAY AND SUNDAY NIGHT
SPREADING RAIN AND SNOW SHOWERS AND COLDER TEMPERATURES ACROSS THE
AREA INTO MONDAY. A WESTERLY FLOW WILL BRING MAINLY DRY AND
SEASONABLE MILD CONDITIONS ON TUESDAY AND WEDNESDAY.

DISCUSSION...COMPLEX VORTEX OVER THE GULF OF ALASKA THIS MORNING
WILL WOBBLE SE TO THE WEST COAST SATURDAY MORNING. MEDIUM RANGE
MODELS CONTINUE TO HANDLE THE INDIVIDUAL VORTICES WITHIN THIS
COMPLEX DIFFERENTLY...BUT AGREE THAT A VERY WARM SW FLOW WILL
PREVAIL OVER THE AREA SATURDAY BETWEEN THIS SYSTEM AND STRONG
DOWNSTREAM RIDGE OVER THE PLAINS. RECORD HIGH TERRITORY FOR THE
25TH IS GENERALLY 72-74F RANGE ACROSS CENTRAL WY FOR THE 25TH...A
BIT WARMER AT WRL AT 79F. FORECAST HIGHS ARE CURRENTLY NEAR OR
EXCEEDING THESE RECORDS.

ON THE 22/00Z GFS AND ECMWF RUNS...GFS CONTINUES TO EJECT LEAD
SHORTWAVE OUT OF BASE OF THE TROUGH NE INTO WESTERN MONTANA
SATURDAY NIGHT WHILE THE ECMWF SHOWS A MORE SPLIT
SYSTEM...SWINGING THIS SHORTWAVE FURTHER SOUTH ACROSS THE GREAT
BASIN SATURDAY NIGHT. GFS VERSION WOULD KEEP MOST OF THE
PRECIPITATION CONFINED TO THE WEST DURING THE DAY SUNDAY WITH
WINDY AND MILD CONDITIONS ACROSS THE CENTRAL AND SOUTH. ECMWF
DEPICTION WOULD RESULT IN MUCH COOLER AND WETTER CONDITIONS ACROSS
THE AREA SUNDAY. EC AND GFS ENSEMBLE MEANS FAVOR SLOWER
PROGRESSION...MORE RESPECT FOR STRONG PLAINS RIDGE.
HOWEVER...EITHER WAY MUCH COLDER AIR WILL SPILL INTO THE AREA
SUNDAY NIGHT BEHIND THE FRONT WITH SNOW LEVELS EXPECTED TO BE
BETWEEN 5-6KFT BY MONDAY MORNING. THE NORTHERN THIRD OF THE AREA
STANDS THE BEST CHANCE FOR SOME ACCUMULATION MONDAY
MORNING...MAINLY ON VEGETATION WITH WET ROADS BELOW 6KFT. COOL AND
UNSETTLED NW FLOW WILL PREVAIL ON THE BACK SIDE OF THE TROUGH
LATTER IN THE DAY MONDAY WITH THE BETTER MOISTURE AND INSTABILITY
EXPECTED OVER THE NE HALF OF THE CWA. ZONAL FLOW WILL DEVELOP
BEHIND THIS TROUGH TUESDAY AND WEDNESDAY...BRINGING IN MILDER
PACIFIC AIRMASS ALONG WITH SOME OROGRAPHIC PRECIPITATION IN THE
WEST.

&&

.AVIATION.../12Z ISSUANCE/

LOW CLOUDS /020-050 KFT AGL/ AND POSSIBLY SOME PATCHY FOG ACROSS
NORTHWEST WYOMING /NW OF A KAFO-KPNA-30W KCOD LINE/ THIS MORNING
WILL BE THE MAIN AVIATION HAZARD FOR THIS SET OF TAFS. THIS WOULD
PRIMARILY IMPACT THE KJAC TERMINAL...WITH CEILINGS AT KJAC PROBABLY
HIGH MVFR TO LOW VFR. FOG CHANCES AT KJAC WILL BE SLIM DUE TO THE
AFOREMENTIONED STRATCU DECK. THIS FOG/LOW CLOUDS ACROSS THE
NORTHWEST ARE EXPECTED TO ERODE BY AROUND 18Z. OTHERWISE...VFR
CONDITIONS WILL OCCUR TODAY WITH MAINLY SKC SKIES AND LIGHT WINDS.
AFTER 00Z...EXPECT INCREASING MID/HIGH LEVEL CLOUDINESS AND
STRENGTHENING MOUNTAIN TOP WINDS WITH POSSIBLY SOME LLWS ON THE LEE
SIDE OF MOUNTAIN RANGES ALONG THE CONTINENTAL DIVIDE DEVELOPING
AFTER 06Z. HOWEVER NOT ENOUGH CONFIDENCE OR MAGNITUDE TO INCLUDE AT
KCOD OR KLND AT THIS TIME.

&&

.FIRE WEATHER...

THE WIND AND THE RAIN WILL CLEAR OUT TODAY WITH COOL TEMPERATURES
REMAINING BEHIND THE FRONT THAT PASSED THROUGH YESTERDAY.
TEMPERATURES REBOUND A BIT ON THURSDAY AS HIGH PRESSURE BUILDS IN
FROM THE SOUTH BUT IT WILL BE ANOTHER BREEZY DAY IN SPOTS WITH
SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN ROCK SPRINGS AND
CASPER AND OVER THE HIGHER ELEVATIONS. SOUTHWEST FLOW RETURNS ON
FRIDAY WITH DRIER AND WARMER CONDITIONS REMAINING. THERE COULD BE A
FEW GUSTS OVER 25 MPH IN THE AFTERNOON BETWEEN RAWLINS AND SOUTHERN
CASPER DISPATCH BUT MOST AREAS WILL HAVE RELATIVELY LIGHT WINDS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...WM
FIRE WEATHER...ALLEN











000
FXUS65 KRIW 220500
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1100 PM MDT TUE OCT 21 2014

.SHORT TERM...TONIGHT THROUGH WEDNESDAY

A COUPLE OF CONVECTIVE BANDS ASCT WITH A PACIFIC COLD
FRONT/VIGOROUS UPPER LEVEL SHORTWAVE PLOWED EAST ACROSS WESTERN WY
THIS MORNING EACH WITH ISOLD LTG STRIKES AND SOME BRIEF HEAVY
RAINFALL IN SOME AREAS. A SKIFF OF SNOW ON THE GROUND WAS NOTED AT
WIND RIVER LAKE. THE SHOWERS WERE DRYING OUT AS THEY CROSS THE
DIVIDE. HOWEVER...THUNDERSTORMS WITH 50 MPH WINDS HAVE DEVELOPED
ACROSS THE WIND RIVER BASIN AND EXTEND DOWN INTO SWEETWATER COUNTY
AS INSTABILITY HAS TRUMPED THE DOWNSLOPE DRYING EFFECT. A WELL
DEVELOPED CIRCULATION IS SEEN OVER CENTRAL IDAHO. LONG AFTER THE
DRY SLOT BEHIND THE AFOREMENTIONED CONVECTION PUNCHES INTO WEST
CENTRAL AND SOUTHWEST WY...WRAP AROUND FROM THE CIRCULATION NOW IN
IDAHO WILL CONTINUE THE THREAT OF MAINLY SNOW SHOWERS IN NW WY AS
THE SNOW LEVEL DROPS TO 6500 FEET THIS EVENING WITH THESE SHOWERS
DIMINISHING AFTER MIDNIGHT TONIGHT. MOST OF THE QG FORCING WITH
THIS WX SYSTEM WILL REMAIN UP IN MONTANA SO EXPECTING MAINLY LIGHT
PRECIP AMOUNTS TONIGHT IN NW WY. HIGH TEMPERATURES WEDNESDAY
BEHIND TODAYS COLD FRONT WILL BE ABOUT THE SAME OUT WEST WHERE
CLOUDS AND SHOWERS HAVE KEPT THOSE AREAS ON THE COOL SIDE
TODAY...BUT WILL AVERAGE ABOUT 10 DEGREES COOLER EAST OF THE
DIVIDE. EXPECT SOME WESTERLY BREEZES FROM KRKS TO KCPR AND AT THE
HIGHER ELEVATIONS EXPECTED WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

BRIEF RIDGING OVER THE AREA WEDNESDAY NIGHT BEFORE INCREASING SW
FLOW ALOFT DEVELOPS. LEE TROUGHING DEVELOPS AS SEVERAL RIPPLES IN
THE FLOW MOVE TO OUR WEST AND NORTH. A STRONG UPPER JET THEN PUSHES
JUST TO THE NORTH LEAVING OUR NRN ZONES IN THE RIGHT EXIT REGION.
CROSS SECTIONS SHOW SOME DECENT 30-40KT MTN TOP FLOW ALONG THE
ABSAROKAS WITH SOME POTENTIAL FOR A WAVE INDUCED CRITICAL LAYER. NOT
SEEING ANY SUSTAINED MOUNTAIN TOP INVERSION BUT AT LEAST SOME
POTENTIAL FOR A DOWNSLOPE WIND EVENT BASED ON THE SOUNDINGS AND
CROSS SECTIONS. RIGHT NOW...JUST LEANING TOWARDS INCREASED WINDS IN
THE FORECAST THURSDAY INTO THURSDAY NIGHT ALONG WITH SPECIFIC
WORDING IN THE HWO FOR WIND GUSTS TO 50 MPH OR MORE ALONG THE CODY
FOOTHILLS MAINLY LATE THURSDAY OR THURSDAY NIGHT. ANOTHER WEAK
RIPPLE MAY ACTUALLY PUSH A WEAK FRONTAL BOUNDARY INTO THE NORTH ON
FRIDAY TEMPERING THE HIGHS SOME.

IN THE EXTENDED PERIOD...THE RIDGE BUILDS OVER THE TEXAS AREA FRIDAY
INTO SATURDAY WITH DECENT RIDGING UP INTO OUR AREA BEFORE SHIFTING
OFF TO THE EAST SOME AS OUR GULF OF ALASKA UPPER LOW OPENS UP AND
MOVES INLAND. MODELS HAVE BEEN STRUGGLING WITH THIS EVOLUTION...
ESPECIALLY IN REGARDS TO HOW MUCH SPLITTING THERE WOULD BE. GFS AND
ECMWF ARE MORE IN STEP WITH LESS SPLITTING WITH THIS WEEKEND SYSTEM
ON THEIR 12Z RUNS. MODELS TO A VARYING DEGREE ARE ALSO TRENDING
TOWARD A SECONDARY COLD SHORTWAVE FOLLOWING QUICKLY BEHIND THIS
SYSTEM SUNDAY NIGHT EXCEPT FOR THE GEM WHICH IS SLOWER AND HOLDS OFF
UNTIL MONDAY. COULD BE ENOUGH COLD AIR FOR A SHORT PERIOD OF LIGHT
SNOW IN CENTRAL WYO SUNDAY NIGHT OR EARLY MONDAY...ESPECIALLY WHERE
IT PRECIPITATES. WILL WATCH THIS CLOSELY OVER THE NEXT COUPLE DAYS.
AFTER THAT...FLAT RIDGE REBUILDS MONDAY NIGHT INTO TUESDAY FOR
REBOUNDING TEMPERATURES.


&&

.AVIATION.../06Z ISSUANCE/

AN AREA OF ISOLATED -SHRA ONGOING...ALONG AND SE OF A KRKS-KCPR
LINE...WILL GRADUALLY SHIFT EAST OF THE AREA BY 09Z. EXCEPT FOR VERY
BRIEF MVFR CONDITIONS IN -SHRA ACTIVITY...VFR CONDITIONS WILL
PREVAIL IN THIS AREA. ACROSS FAR NORTHWEST WYOMING LOW CLOUDS AND
SOME SNOW SHOWER ACTIVITY WILL BE POSSIBLE FOR THE REST OF THE
NIGHT. THE SNOW SHOWER ACTIVITY IS EXPECTED TO DECREASE TO ONLY SOME
FLURRIES BY 12Z. BETWEEN 12Z AND 18Z THE MAIN CONCERN WILL BE LOW
CLOUDS /020-050 KFT AGL/ AND POSSIBLY SOME PATCHY FOG ACROSS
NORTHWEST WYOMING /NW OF A KAFO-KPNA-30W KCOD LINE/. THIS WOULD
PRIMARILY IMPACT THE KJAC TERMINAL...WITH CEILINGS AT KJAC PROBABLY
HIGH MVFR TO LOW VFR. FOG CHANCES AT KJAC WILL BE SLIM DUE TO THE
AFOREMENTIONED STRATCU DECK. THIS FOG/LOW CLOUDS ACROSS THE
NORTHWEST ARE EXPECTED TO ERODE BY AROUND 18Z. OTHERWISE...VFR
CONDITIONS WILL OCCUR FOR THE REST OF TONIGHT WITH SKC CONDITIONS
AND BREEZY WINDS BECOMING LIGHTER AS THE NIGHT PROGRESSES WITH
MAINLY LIGHT WIND DURING THE DAY WEDNESDAY.  AFTER 00Z...EXPECT
INCREASING MID/HIGH LEVEL CLOUDINESS AND STRENGTHENING MOUNTAIN TOP
WINDS WITH POSSIBLY SOME LLWS ON THE LEE SIDE OF MOUNTAIN RANGES
ALONG THE CONTINENTAL DIVIDE DEVELOPING AFTER 06Z THURSDAY.

&&

.FIRE WEATHER...

WINDY CONDITIONS ARE EXPECTED FOR THE REST OF THE AFTERNOON AND
EARLY EVENING. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR WETTING
RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE POTENTIAL
ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE...ESPECIALLY
NORTHWEST WYOMING THROUGH THIS EVENING. A COLD FRONT SWEEPS THROUGH
TONIGHT...CHANGING THE WIND DIRECTION TO MORE WESTERLY EVERYWHERE.
THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY WITH COOL
TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON THURSDAY AS
HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE ANOTHER BREEZY
DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN
ROCK SPRINGS AND CASPER AND OVER THE HIGHER ELEVATIONS.

&&

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

&&

$$

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










000
FXUS65 KRIW 220500
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1100 PM MDT TUE OCT 21 2014

.SHORT TERM...TONIGHT THROUGH WEDNESDAY

A COUPLE OF CONVECTIVE BANDS ASCT WITH A PACIFIC COLD
FRONT/VIGOROUS UPPER LEVEL SHORTWAVE PLOWED EAST ACROSS WESTERN WY
THIS MORNING EACH WITH ISOLD LTG STRIKES AND SOME BRIEF HEAVY
RAINFALL IN SOME AREAS. A SKIFF OF SNOW ON THE GROUND WAS NOTED AT
WIND RIVER LAKE. THE SHOWERS WERE DRYING OUT AS THEY CROSS THE
DIVIDE. HOWEVER...THUNDERSTORMS WITH 50 MPH WINDS HAVE DEVELOPED
ACROSS THE WIND RIVER BASIN AND EXTEND DOWN INTO SWEETWATER COUNTY
AS INSTABILITY HAS TRUMPED THE DOWNSLOPE DRYING EFFECT. A WELL
DEVELOPED CIRCULATION IS SEEN OVER CENTRAL IDAHO. LONG AFTER THE
DRY SLOT BEHIND THE AFOREMENTIONED CONVECTION PUNCHES INTO WEST
CENTRAL AND SOUTHWEST WY...WRAP AROUND FROM THE CIRCULATION NOW IN
IDAHO WILL CONTINUE THE THREAT OF MAINLY SNOW SHOWERS IN NW WY AS
THE SNOW LEVEL DROPS TO 6500 FEET THIS EVENING WITH THESE SHOWERS
DIMINISHING AFTER MIDNIGHT TONIGHT. MOST OF THE QG FORCING WITH
THIS WX SYSTEM WILL REMAIN UP IN MONTANA SO EXPECTING MAINLY LIGHT
PRECIP AMOUNTS TONIGHT IN NW WY. HIGH TEMPERATURES WEDNESDAY
BEHIND TODAYS COLD FRONT WILL BE ABOUT THE SAME OUT WEST WHERE
CLOUDS AND SHOWERS HAVE KEPT THOSE AREAS ON THE COOL SIDE
TODAY...BUT WILL AVERAGE ABOUT 10 DEGREES COOLER EAST OF THE
DIVIDE. EXPECT SOME WESTERLY BREEZES FROM KRKS TO KCPR AND AT THE
HIGHER ELEVATIONS EXPECTED WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

BRIEF RIDGING OVER THE AREA WEDNESDAY NIGHT BEFORE INCREASING SW
FLOW ALOFT DEVELOPS. LEE TROUGHING DEVELOPS AS SEVERAL RIPPLES IN
THE FLOW MOVE TO OUR WEST AND NORTH. A STRONG UPPER JET THEN PUSHES
JUST TO THE NORTH LEAVING OUR NRN ZONES IN THE RIGHT EXIT REGION.
CROSS SECTIONS SHOW SOME DECENT 30-40KT MTN TOP FLOW ALONG THE
ABSAROKAS WITH SOME POTENTIAL FOR A WAVE INDUCED CRITICAL LAYER. NOT
SEEING ANY SUSTAINED MOUNTAIN TOP INVERSION BUT AT LEAST SOME
POTENTIAL FOR A DOWNSLOPE WIND EVENT BASED ON THE SOUNDINGS AND
CROSS SECTIONS. RIGHT NOW...JUST LEANING TOWARDS INCREASED WINDS IN
THE FORECAST THURSDAY INTO THURSDAY NIGHT ALONG WITH SPECIFIC
WORDING IN THE HWO FOR WIND GUSTS TO 50 MPH OR MORE ALONG THE CODY
FOOTHILLS MAINLY LATE THURSDAY OR THURSDAY NIGHT. ANOTHER WEAK
RIPPLE MAY ACTUALLY PUSH A WEAK FRONTAL BOUNDARY INTO THE NORTH ON
FRIDAY TEMPERING THE HIGHS SOME.

IN THE EXTENDED PERIOD...THE RIDGE BUILDS OVER THE TEXAS AREA FRIDAY
INTO SATURDAY WITH DECENT RIDGING UP INTO OUR AREA BEFORE SHIFTING
OFF TO THE EAST SOME AS OUR GULF OF ALASKA UPPER LOW OPENS UP AND
MOVES INLAND. MODELS HAVE BEEN STRUGGLING WITH THIS EVOLUTION...
ESPECIALLY IN REGARDS TO HOW MUCH SPLITTING THERE WOULD BE. GFS AND
ECMWF ARE MORE IN STEP WITH LESS SPLITTING WITH THIS WEEKEND SYSTEM
ON THEIR 12Z RUNS. MODELS TO A VARYING DEGREE ARE ALSO TRENDING
TOWARD A SECONDARY COLD SHORTWAVE FOLLOWING QUICKLY BEHIND THIS
SYSTEM SUNDAY NIGHT EXCEPT FOR THE GEM WHICH IS SLOWER AND HOLDS OFF
UNTIL MONDAY. COULD BE ENOUGH COLD AIR FOR A SHORT PERIOD OF LIGHT
SNOW IN CENTRAL WYO SUNDAY NIGHT OR EARLY MONDAY...ESPECIALLY WHERE
IT PRECIPITATES. WILL WATCH THIS CLOSELY OVER THE NEXT COUPLE DAYS.
AFTER THAT...FLAT RIDGE REBUILDS MONDAY NIGHT INTO TUESDAY FOR
REBOUNDING TEMPERATURES.


&&

.AVIATION.../06Z ISSUANCE/

AN AREA OF ISOLATED -SHRA ONGOING...ALONG AND SE OF A KRKS-KCPR
LINE...WILL GRADUALLY SHIFT EAST OF THE AREA BY 09Z. EXCEPT FOR VERY
BRIEF MVFR CONDITIONS IN -SHRA ACTIVITY...VFR CONDITIONS WILL
PREVAIL IN THIS AREA. ACROSS FAR NORTHWEST WYOMING LOW CLOUDS AND
SOME SNOW SHOWER ACTIVITY WILL BE POSSIBLE FOR THE REST OF THE
NIGHT. THE SNOW SHOWER ACTIVITY IS EXPECTED TO DECREASE TO ONLY SOME
FLURRIES BY 12Z. BETWEEN 12Z AND 18Z THE MAIN CONCERN WILL BE LOW
CLOUDS /020-050 KFT AGL/ AND POSSIBLY SOME PATCHY FOG ACROSS
NORTHWEST WYOMING /NW OF A KAFO-KPNA-30W KCOD LINE/. THIS WOULD
PRIMARILY IMPACT THE KJAC TERMINAL...WITH CEILINGS AT KJAC PROBABLY
HIGH MVFR TO LOW VFR. FOG CHANCES AT KJAC WILL BE SLIM DUE TO THE
AFOREMENTIONED STRATCU DECK. THIS FOG/LOW CLOUDS ACROSS THE
NORTHWEST ARE EXPECTED TO ERODE BY AROUND 18Z. OTHERWISE...VFR
CONDITIONS WILL OCCUR FOR THE REST OF TONIGHT WITH SKC CONDITIONS
AND BREEZY WINDS BECOMING LIGHTER AS THE NIGHT PROGRESSES WITH
MAINLY LIGHT WIND DURING THE DAY WEDNESDAY.  AFTER 00Z...EXPECT
INCREASING MID/HIGH LEVEL CLOUDINESS AND STRENGTHENING MOUNTAIN TOP
WINDS WITH POSSIBLY SOME LLWS ON THE LEE SIDE OF MOUNTAIN RANGES
ALONG THE CONTINENTAL DIVIDE DEVELOPING AFTER 06Z THURSDAY.

&&

.FIRE WEATHER...

WINDY CONDITIONS ARE EXPECTED FOR THE REST OF THE AFTERNOON AND
EARLY EVENING. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR WETTING
RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE POTENTIAL
ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE...ESPECIALLY
NORTHWEST WYOMING THROUGH THIS EVENING. A COLD FRONT SWEEPS THROUGH
TONIGHT...CHANGING THE WIND DIRECTION TO MORE WESTERLY EVERYWHERE.
THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY WITH COOL
TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON THURSDAY AS
HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE ANOTHER BREEZY
DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH COMMON BETWEEN
ROCK SPRINGS AND CASPER AND OVER THE HIGHER ELEVATIONS.

&&

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

&&

$$

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










000
FXUS65 KRIW 212050
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
250 PM MDT TUE OCT 21 2014

.SHORT TERM...TONIGHT THROUGH WEDNESDAY
A COUPLE OF CONVECTIVE BANDS ASCT WITH A PACIFIC COLD
FRONT/VIGOROUS UPPER LEVEL SHORTWAVE PLOWED EAST ACROSS WESTERN WY
THIS MORNING EACH WITH ISOLD LTG STRIKES AND SOME BRIEF HEAVY
RAINFALL IN SOME AREAS. A SKIFF OF SNOW ON THE GROUND WAS NOTED AT
WIND RIVER LAKE. THE SHOWERS WERE DRYING OUT AS THEY CROSS THE
DIVIDE. HOWEVER...THUNDERSTORMS WITH 50 MPH WINDS HAVE DEVELOPED
ACROSS THE WIND RIVER BASIN AND EXTEND DOWN INTO SWEETWATER COUNTY
AS INSTABILITY HAS TRUMPED THE DOWNSLOPE DRYING EFFECT. A WELL
DEVELOPED CIRCULATION IS SEEN OVER CENTRAL IDAHO. LONG AFTER THE
DRY SLOT BEHIND THE AFOREMENTIONED CONVECTION PUNCHES INTO WEST
CENTRAL AND SOUTHWEST WY...WRAP AROUND FROM THE CIRCULATION NOW IN
IDAHO WILL CONTINUE THE THREAT OF MAINLY SNOW SHOWERS IN NW WY AS
THE SNOW LEVEL DROPS TO 6500 FEET THIS EVENING WITH THESE SHOWERS
DIMINISHING AFTER MIDNIGHT TONIGHT. MOST OF THE QG FORCING WITH
THIS WX SYSTEM WILL REMAIN UP IN MONTANA SO EXPECTING MAINLY LIGHT
PRECIP AMOUNTS TONIGHT IN NW WY. HIGH TEMPERATURES WEDNESDAY
BEHIND TODAYS COLD FRONT WILL BE ABOUT THE SAME OUT WEST WHERE
CLOUDS AND SHOWERS HAVE KEPT THOSE AREAS ON THE COOL SIDE
TODAY...BUT WILL AVERAGE ABOUT 10 DEGREES COOLER EAST OF THE
DIVIDE. EXPECT SOME WESTERLY BREEZES FROM KRKS TO KCPR AND AT THE
HIGHER ELEVATIONS EXPECTED WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

BRIEF RIDGING OVER THE AREA WEDNESDAY NIGHT BEFORE INCREASING SW
FLOW ALOFT DEVELOPS. LEE TROUGHING DEVELOPS AS SEVERAL RIPPLES IN
THE FLOW MOVE TO OUR WEST AND NORTH. A STRONG UPPER JET THEN PUSHES
JUST TO THE NORTH LEAVING OUR NRN ZONES IN THE RIGHT EXIT REGION.
CROSS SECTIONS SHOW SOME DECENT 30-40KT MTN TOP FLOW ALONG THE
ABSAROKAS WITH SOME POTENTIAL FOR A WAVE INDUCED CRITICAL LAYER. NOT
SEEING ANY SUSTAINED MOUNTAIN TOP INVERSION BUT AT LEAST SOME
POTENTIAL FOR A DOWNSLOPE WIND EVENT BASED ON THE SOUNDINGS AND
CROSS SECTIONS. RIGHT NOW...JUST LEANING TOWARDS INCREASED WINDS IN
THE FORECAST THURSDAY INTO THURSDAY NIGHT ALONG WITH SPECIFIC
WORDING IN THE HWO FOR WIND GUSTS TO 50 MPH OR MORE ALONG THE CODY
FOOTHILLS MAINLY LATE THURSDAY OR THURSDAY NIGHT. ANOTHER WEAK
RIPPLE MAY ACTUALLY PUSH A WEAK FRONTAL BOUNDARY INTO THE NORTH ON
FRIDAY TEMPERING THE HIGHS SOME.

IN THE EXTENDED PERIOD...THE RIDGE BUILDS OVER THE TEXAS AREA FRIDAY
INTO SATURDAY WITH DECENT RIDGING UP INTO OUR AREA BEFORE SHIFTING
OFF TO THE EAST SOME AS OUR GULF OF ALASKA UPPER LOW OPENS UP AND
MOVES INLAND. MODELS HAVE BEEN STRUGGLING WITH THIS EVOLUTION...
ESPECIALLY IN REGARDS TO HOW MUCH SPLITTING THERE WOULD BE. GFS AND
ECMWF ARE MORE IN STEP WITH LESS SPLITTING WITH THIS WEEKEND SYSTEM
ON THEIR 12Z RUNS. MODELS TO A VARYING DEGREE ARE ALSO TRENDING
TOWARD A SECONDARY COLD SHORTWAVE FOLLOWING QUICKLY BEHIND THIS
SYSTEM SUNDAY NIGHT EXCEPT FOR THE GEM WHICH IS SLOWER AND HOLDS OFF
UNTIL MONDAY. COULD BE ENOUGH COLD AIR FOR A SHORT PERIOD OF LIGHT
SNOW IN CENTRAL WYO SUNDAY NIGHT OR EARLY MONDAY...ESPECIALLY WHERE
IT PRECIPITATES. WILL WATCH THIS CLOSELY OVER THE NEXT COUPLE DAYS.
AFTER THAT...FLAT RIDGE REBUILDS MONDAY NIGHT INTO TUESDAY FOR
REBOUNDING TEMPERATURES.


&&

.AVIATION.../00Z ISSUANCE/
SHORTWAVE APPROACHING SOUTHWEST IDAHO WILL SWING ACROSS NORTHWEST
WYOMING TODAY. CLOUD COVER...SHOWERS AND ISOLATED THUNDERSTORMS WILL
BE ON THE DECREASE THROUGH 00Z TODAY ACROSS WEST CENTRAL AND
SOUTHWEST WY INCLUDING KJAC AND KAFO AS BEST FORCING AND JET ENERGY
PUSH ACROSS WYOMING. HOWEVER...EAST OF THE DIVIDE...SCATTERED
THUNDERSTORMS CAN BE EXPECTED ACROSS HOT SPRINGS AND FREMONT
COUNTIES ALONG WITH 40 TO 50 MPH WINDS...INCLUDING KRIW AND KLND
THROUGH 22Z. HOWEVER...MAINLY SNOW SHOWERS WILL CONTINUE ACROSS
NORTHWEST WY INCLUDING YELLOWSTONE PARK AS SNOW LEVELS DROP TO
6500 FEET THROUGH THIS EVENING AS MOISTURE WRAPS AROUND THE
CIRCULATION NOW OVER IDAHO THAT WILL TRACK TO MT. MOUNTAIN TOP
OBSCURATIONS WILL BE WIDESPREAD THROUGH ABOUT 21Z-23Z BEFORE
TROUGH AND ASSOCIATED COLD FRONT SWING EAST OF KJAC BUT WILL
LINGER THROUGH 06Z AT YNP. CANNOT RULE OUT A BRIEF PERIOD OF MVFR
AT KJAC WITH A HEAVIER RAIN SHOWER THROUGH 21Z TODAY.
OTHERWISE...KJAC WILL REMAIN VFR WITH RAPID CLEARING BETWEEN
23Z/TODAY AND 02Z/WED. OTHER TERMINALS WILL ALL BE VFR THROUGH THE
PERIOD. EXPECT ENOUGH INSTABILITY AND MOISTURE TO GENERATE
CONVECTION ACROSS SOUTHWEST WYOMING...AFFECTING THE KRKS TERMINAL
THROUGH 22Z OR SO. MUCH MORE ISOLATED CONVECTION ELSEWHERE.
LARGER ISSUE EAST OF THE DIVIDE WILL BE DOWNSLOPE WINDS NEAR THE
MOUNTAINS AND FOOTHILLS AND GUSTY SOUTH TO WEST SURFACE WIND.
WINDS WILL BE 15-20KTS WITH GUSTS 25-35KTS. STRONGEST NON
THUNDERSTORM WINDS WILL BE THROUGH 23Z THIS AFTERNOON AT KCPR
WHERE 25G35KTS IS LIKELY. TROUGH PASSAGE BETWEEN 00Z- 06Z/WED WILL
VEER WINDS TO THE NORTHWEST WITH DECREASING SPEEDS AFTER SUNSET.
THE EXCEPTION WILL BE KRIW WHERE FAVORABLE NORTHWEST WIND OF
15-25KTS IS LIKELY THROUGH ABOUT 06Z/WED. ALL TERMINALS WILL SEE
RAPID CLEARING FROM THE WEST BEGINNING AT 00Z/WED AND CONTINUING
THROUGH 06Z/WED.

&&

.FIRE WEATHER...
WINDY CONDITIONS ARE EXPECTED FOR THE REST OF THE AFTERNOON AND
EARLY EVENING. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR WETTING
RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE POTENTIAL
ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE...ESPECIALLY
NORTHWEST WYOMING THROUGH THIS EVENING. A COLD FRONT SWEEPS
THROUGH TONIGHT...CHANGING THE WIND DIRECTION TO MORE WESTERLY EVERYWHERE.
THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY WITH COOL
TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON THURSDAY AS
HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE ANOTHER
BREEZY DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH COMMON
BETWEEN ROCK SPRINGS AND CASPER AND OVER THE HIGHER ELEVATIONS.

&&

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

$$

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







000
FXUS65 KRIW 212026
AFDRIW

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE RIVERTON WY
225 PM MDT TUE OCT 21 2014

.SHORT TERM...TODAY THROUGH THURSDAY NIGHT

SWIFT SOUTHWEST FLOW DEVELOPING TODAY AHEAD OF AN APPROACHING SHORT
WAVE TROUGH. WIND SPEEDS WILL BE ELEVATED BUT BELOW WARNING
CRITERIA...MAIN IMPACT WILL BE TO LIGHT TRAILERS AND HIGH PROFILE
VEHICLES...ESPECIALLY IN SWEETWATER COUNTY...SOUTHEAST FREMONT AND
NATRONA COUNTIES. LATER ON THIS EVENING...THE STRONGER WINDS WILL BE
FOUND ALONG THE ABSAROKAS AND INTO THE CODY FOOTHILLS...AND UPPER
WIND RIVER BASIN AS THE FLOW TURNS A LITTLE MORE WESTERLY
...INCREASING THE BREAKING MOUNTAIN WAVE THREAT. FLOW WILL LIKELY BE
TOO QUICK AND SOUTHWESTERLY AT FIRST AND WILL SAIL RIGHT OVER THE
BARRIER BUT THERE COULD BE SOME BREAKING ACTION EARLY IN THE
EVENING...ESPECIALLY IN WEST CODY AND AROUND CLARK AS WINDS VEER
MORE WESTERLY. THIS IS EXPECTED TO BE BRIEF AS THE SUBSIDENCE LEFT
ENTRANCE REGION OF THE JET SAILS BY EARLY IN THE EVENING FOLLOWED BY
SOME BROAD BUT WEAKER FORCING FOR DESCENT BEHIND THE EXITING TROUGH.

WHILE THERE IS LIMITED MOISTURE WITH THIS SYSTEM THERE WILL BE AT
LEAST SOME RAIN AND SNOW...WITH ANY MEASURABLE PRECIPITATION
EXPECTED TO BE LIMITED TO AREAS ALONG AND WEST OF THE
DIVIDE...INCLUDING SWEETWATER COUNTY. DOWNSLOPING EAST OF THE DIVIDE
SHOULD LIMIT ANY PRECIPITATION THERE. THERE WILL BE SOME JET
ENERGY..WEAK INSTABILITY AND SOME QG FORCING HELPING TO MAXIMIZE THE
POTENTIAL OF THIS WAVE SO THERE COULD BE A FEW SHOWERS MAKE IT OVER
THE MOUNTAINS. RECENT MODEL RUNS HAVE TAKEN THE BULK OF THE ENERGY
FROM THIS WAVE A LITTLE FURTHER NORTH THAN PREVIOUS RUNS...BUT POPS
LARGELY LEFT ALONE...WITH SOME TRIMMING IN A FEW AREAS BUT OVERALL
NOT MUCH CHANGE IN CONTINUITY WITH PREVIOUS FORECAST.

THE MODELS HAVE ALSO BEEN BACKING OFF ON H7 TEMPERATURES ALONG AND
BEHIND THE COLD FRONT. SNOW LEVELS WILL NOW BE ONLY AS LOW AS 8KFT
ACROSS THE WESTERN MOUNTAINS LOWERING TO 6.5KFT THIS EVENING BEFORE
THE SYSTEM EXITS...HIGHER AS YOU HEAD EAST. THE FRONT EVENTUALLY
MAKES IT ALL THE WAY THROUGH THE STATE TONIGHT...WITH THE COOLER
AIRMASS HANGING AROUND INTO WEDNESDAY WITH SOME MODERATION ON
THURSDAY. THURSDAY COULD ALSO BE A BREEZY DAY AS A TUG OF WAR
BETWEEN THE COLD BUT DYNAMIC TROUGH TO OUR NORTH AND THE RIDGE
POKING IN FROM THE SOUTH. OVERALL IT LOOKS LIKE THE RIDGE WILL WIN
OUT IN OUR AREA WITH REBOUNDING TEMPERATURES EXPECTED.

.LONG TERM...FRIDAY THROUGH TUESDAY

SYNOPSIS...UNSEASONABLY MILD AND MAINLY DRY CONDITIONS WILL PREVAIL
FRIDAY AND SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE ACROSS
CENTRAL AND SOUTHERN WYOMING ALONG WITH BREEZY/WINDY AREAS.  A
TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT WILL PUSH ACROSS
WYOMING ON SUNDAY/SUNDAY NIGHT BRINGING CHANCES OF RAIN AND SNOW
SHOWERS.  A DRIER AND COOL AIRMASS WILL FOLLOW ON MONDAY.

DISCUSSION...UPPER LOW OVER SW ALASKA EARLY THIS MORNING IS FORECAST
TO WOBBLE SE ALONG THE COAST OF BRITISH COLUMBIA WITH UPPER TROUGH
SHARPENING AND BECOMING MORE UPRIGHT OFF THE WEST COAST ON
FRIDAY...PUMPING UP RIDGE OVER THE HIGH PLAINS.  MEDIUM-RANGE MODELS
IN GOOD AGREEMENT UP TO THIS POINT.  MODEL DIFFERENCES BECOME MORE
APPARENT AS THE TROUGH MAKES LANDFALL ALONG THE COAST FRIDAY NIGHT
AND SATURDAY WITH THE GFS SHEARING LEAD SHORTWAVE NE ACROSS
IDAHO/WESTERN MONTANA ON SATURDAY WHILE THE ECMWF SHOWS A SLOWER
MUCH MORE SPLIT TROUGH PUSHING ACROSS THE ROCKIES ON SUNDAY.  GFS
AND EC RESPECTIVE ENSEMBLE MEANS SUPPORT SLOWER OVERALL PROGRESSION
THAN GFS AND NOT AS MUCH SPLITTING AS ECMWF DETERMINISTIC GUIDANCE.
FORECAST LEANS TOWARD THE ENSEMBLE MEANS WITH COLD FRONT PUSHING
INTO THE WEST LATE SATURDAY/SATURDAY NIGHT WITH INCREASING POPS
ACROSS THE WEST AND SPREADING ACROSS CENTRAL AREAS SUNDAY AND SUNDAY
NIGHT.  GEFS MEAN KEEP THE BEST CHANCES OF PRECIPITATION NORTH AND
WEST OF WYOMING WITH DOWNSLOPE FLOW KEEPING CHANCES OF PRECIPITATION
LOW EAST OF THE DIVIDE.  ENSEMBLE MEANS ALSO SHOW HEIGHTS REBOUNDING
A BIT QUICKER MONDAY AS NEXT TROUGH APPROACHES THE NW COAST WITH
FLAT RIDGING OVER THE AREA ON TUESDAY.  FORECAST KEEPS LOW POPS OVER
THE MOUNTAINS ON MONDAY DRY AND SEASONABLY COOL TEMPERATURES ACROSS
THE BASINS AND VALLEYS.  MILDER...ABOVE NORMAL TEMPERATURES ARE
EXPECTED ON TUESDAY.

&&

.AVIATION.../18Z ISSUANCE/

SHORTWAVE APPROACHING SOUTHWEST IDAHO WILL SWING ACROSS NORTHWEST
WYOMING TODAY. CLOUD COVER...SHOWERS AND ISOLATED THUNDERSTORMS WILL
BE ON THE DECREASE THROUGH 00Z TODAY ACROSS WEST CENTRAL AND
SOUTHWEST WY INCLUDING KJAC AND KAFO AS BEST FORCING AND JET ENERGY
PUSH ACROSS WYOMING. HOWEVER...EAST OF THE DIVIDE...SCATTERED
THUNDERSTORMS CAN BE EXPECTED ACROSS HOT SPRINGS AND FREMONT
COUNTIES ALONG WITH 40 TO 50 MPH WINDS...INCLUDING KRIW AND KLND.
HOWEVER...MAINLY SNOW SHOWERS WILL CONTINUE ACROSS NORTHWEST WY
INCLUDING YELLOWSTONE PARK AS SNOW LEVELS DROP TO 6500 FEET THROUGH
THIS EVENING AS MOISTURE WRAPS AROUND THE CIRCULATION NOW OVER IDAHO
THAT WILL TRACK TO MT. MOUNTAIN TOP OBSCURATIONS WILL BE WIDESPREAD
THROUGH ABOUT 21Z-23Z BEFORE TROUGH AND ASSOCIATED COLD FRONT SWING
EAST OF KJAC BUT WILL LINGER THROUGH 06Z AT YNP. CANNOT RULE OUT A
BRIEF PERIOD OF MVFR AT KJAC WITH A HEAVIER RAIN SHOWER THROUGH 21Z
TODAY. OTHERWISE...KJAC WILL REMAIN VFR WITH RAPID CLEARING BETWEEN
23Z/TODAY AND 02Z/WED. OTHER TERMINALS WILL ALL BE VFR THROUGH THE
PERIOD. EXPECT ENOUGH INSTABILITY AND MOISTURE TO GENERATE
CONVECTION ACROSS SOUTHWEST WYOMING...MAINLY AFFECTING
KBPI...KPNA...AND KRKS TERMINALS FOR THE NEXT HOUR OR TWO. MUCH MORE
ISOLATED CONVECTION ELSEWHERE. LARGER ISSUE EAST OF THE DIVIDE WILL
BE DOWNSLOPE WINDS NEAR THE MOUNTAINS AND FOOTHILLS AND GUSTY SOUTH
TO WEST SURFACE WIND. WINDS WILL BE 15-20KTS WITH GUSTS 25-35KTS.
STRONGEST WIND WILL BE THROUGH 23Z THIS AFTERNOON AT KCPR WHERE
25G35KTS IS LIKELY. TROUGH PASSAGE BETWEEN 00Z-06Z/WED WILL VEER
WINDS TO THE NORTHWEST WITH DECREASING SPEEDS AFTER SUNSET. THE
EXCEPTION WILL BE KRIW WHERE FAVORABLE NORTHWEST WIND OF 15-25KTS IS
LIKELY THROUGH ABOUT 06Z/WED. ALL TERMINALS WILL SEE RAPID CLEARING
FROM THE WEST BEGINNING AT 00Z/WED AND CONTINUING THROUGH 06Z/WED.

&&

.FIRE WEATHER...

ANOTHER UNSEASONABLY WARM AND WINDY DAY EAST OF THE DIVIDE WHILE A
STORM MOVES INTO THE WEST. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR
WETTING RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE
POTENTIAL ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE.
THERE COULD ALSO BE SOME WETTING RAINS IN RAWLINS DISPATCH AREA. A
COLD FRONT SWEEPS THROUGH TONIGHT...CHANGING THE WIND DIRECTION TO
MORE WESTERLY. THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY
WITH COOL TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON
THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE
ANOTHER BREEZY DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH
COMMON BETWEEN ROCK SPRINGS AND CASPER AND OVER THE HIGHER
ELEVATIONS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ/LIPSON
FIRE WEATHER...ALLEN

















000
FXUS65 KRIW 211905
AFDRIW

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE RIVERTON WY
104 PM MDT TUE OCT 21 2014

.SHORT TERM...TODAY THROUGH THURSDAY NIGHT

SWIFT SOUTHWEST FLOW DEVELOPING TODAY AHEAD OF AN APPROACHING SHORT
WAVE TROUGH. WIND SPEEDS WILL BE ELEVATED BUT BELOW WARNING
CRITERIA...MAIN IMPACT WILL BE TO LIGHT TRAILERS AND HIGH PROFILE
VEHICLES...ESPECIALLY IN SWEETWATER COUNTY...SOUTHEAST FREMONT AND
NATRONA COUNTIES. LATER ON THIS EVENING...THE STRONGER WINDS WILL BE
FOUND ALONG THE ABSAROKAS AND INTO THE CODY FOOTHILLS...AND UPPER
WIND RIVER BASIN AS THE FLOW TURNS A LITTLE MORE WESTERLY
...INCREASING THE BREAKING MOUNTAIN WAVE THREAT. FLOW WILL LIKELY BE
TOO QUICK AND SOUTHWESTERLY AT FIRST AND WILL SAIL RIGHT OVER THE
BARRIER BUT THERE COULD BE SOME BREAKING ACTION EARLY IN THE
EVENING...ESPECIALLY IN WEST CODY AND AROUND CLARK AS WINDS VEER
MORE WESTERLY. THIS IS EXPECTED TO BE BRIEF AS THE SUBSIDENCE LEFT
ENTRANCE REGION OF THE JET SAILS BY EARLY IN THE EVENING FOLLOWED BY
SOME BROAD BUT WEAKER FORCING FOR DESCENT BEHIND THE EXITING TROUGH.

WHILE THERE IS LIMITED MOISTURE WITH THIS SYSTEM THERE WILL BE AT
LEAST SOME RAIN AND SNOW...WITH ANY MEASURABLE PRECIPITATION
EXPECTED TO BE LIMITED TO AREAS ALONG AND WEST OF THE
DIVIDE...INCLUDING SWEETWATER COUNTY. DOWNSLOPING EAST OF THE DIVIDE
SHOULD LIMIT ANY PRECIPITATION THERE. THERE WILL BE SOME JET
ENERGY..WEAK INSTABILITY AND SOME QG FORCING HELPING TO MAXIMIZE THE
POTENTIAL OF THIS WAVE SO THERE COULD BE A FEW SHOWERS MAKE IT OVER
THE MOUNTAINS. RECENT MODEL RUNS HAVE TAKEN THE BULK OF THE ENERGY
FROM THIS WAVE A LITTLE FURTHER NORTH THAN PREVIOUS RUNS...BUT POPS
LARGELY LEFT ALONE...WITH SOME TRIMMING IN A FEW AREAS BUT OVERALL
NOT MUCH CHANGE IN CONTINUITY WITH PREVIOUS FORECAST.

THE MODELS HAVE ALSO BEEN BACKING OFF ON H7 TEMPERATURES ALONG AND
BEHIND THE COLD FRONT. SNOW LEVELS WILL NOW BE ONLY AS LOW AS 8KFT
ACROSS THE WESTERN MOUNTAINS LOWERING TO 6.5KFT THIS EVENING BEFORE
THE SYSTEM EXITS...HIGHER AS YOU HEAD EAST. THE FRONT EVENTUALLY
MAKES IT ALL THE WAY THROUGH THE STATE TONIGHT...WITH THE COOLER
AIRMASS HANGING AROUND INTO WEDNESDAY WITH SOME MODERATION ON
THURSDAY. THURSDAY COULD ALSO BE A BREEZY DAY AS A TUG OF WAR
BETWEEN THE COLD BUT DYNAMIC TROUGH TO OUR NORTH AND THE RIDGE
POKING IN FROM THE SOUTH. OVERALL IT LOOKS LIKE THE RIDGE WILL WIN
OUT IN OUR AREA WITH REBOUNDING TEMPERATURES EXPECTED.

.LONG TERM...FRIDAY THROUGH TUESDAY

SYNOPSIS...UNSEASONABLY MILD AND MAINLY DRY CONDITIONS WILL PREVAIL
FRIDAY AND SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE ACROSS
CENTRAL AND SOUTHERN WYOMING ALONG WITH BREEZY/WINDY AREAS.  A
TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT WILL PUSH ACROSS
WYOMING ON SUNDAY/SUNDAY NIGHT BRINGING CHANCES OF RAIN AND SNOW
SHOWERS.  A DRIER AND COOL AIRMASS WILL FOLLOW ON MONDAY.

DISCUSSION...UPPER LOW OVER SW ALASKA EARLY THIS MORNING IS FORECAST
TO WOBBLE SE ALONG THE COAST OF BRITISH COLUMBIA WITH UPPER TROUGH
SHARPENING AND BECOMING MORE UPRIGHT OFF THE WEST COAST ON
FRIDAY...PUMPING UP RIDGE OVER THE HIGH PLAINS.  MEDIUM-RANGE MODELS
IN GOOD AGREEMENT UP TO THIS POINT.  MODEL DIFFERENCES BECOME MORE
APPARENT AS THE TROUGH MAKES LANDFALL ALONG THE COAST FRIDAY NIGHT
AND SATURDAY WITH THE GFS SHEARING LEAD SHORTWAVE NE ACROSS
IDAHO/WESTERN MONTANA ON SATURDAY WHILE THE ECMWF SHOWS A SLOWER
MUCH MORE SPLIT TROUGH PUSHING ACROSS THE ROCKIES ON SUNDAY.  GFS
AND EC RESPECTIVE ENSEMBLE MEANS SUPPORT SLOWER OVERALL PROGRESSION
THAN GFS AND NOT AS MUCH SPLITTING AS ECMWF DETERMINISTIC GUIDANCE.
FORECAST LEANS TOWARD THE ENSEMBLE MEANS WITH COLD FRONT PUSHING
INTO THE WEST LATE SATURDAY/SATURDAY NIGHT WITH INCREASING POPS
ACROSS THE WEST AND SPREADING ACROSS CENTRAL AREAS SUNDAY AND SUNDAY
NIGHT.  GEFS MEAN KEEP THE BEST CHANCES OF PRECIPITATION NORTH AND
WEST OF WYOMING WITH DOWNSLOPE FLOW KEEPING CHANCES OF PRECIPITATION
LOW EAST OF THE DIVIDE.  ENSEMBLE MEANS ALSO SHOW HEIGHTS REBOUNDING
A BIT QUICKER MONDAY AS NEXT TROUGH APPROACHES THE NW COAST WITH
FLAT RIDGING OVER THE AREA ON TUESDAY.  FORECAST KEEPS LOW POPS OVER
THE MOUNTAINS ON MONDAY DRY AND SEASONABLY COOL TEMPERATURES ACROSS
THE BASINS AND VALLEYS.  MILDER...ABOVE NORMAL TEMPERATURES ARE
EXPECTED ON TUESDAY.

&&

.AVIATION.../18Z ISSUANCE/

SHORTWAVE APPROACHING SOUTHWEST IDAHO WILL SWING ACROSS NORTHWEST
WYOMING TODAY. CLOUD COVER...SHOWERS AND ISOLATED THUNDERSTORMS WILL
BE ON THE DECREASE THROUGH 00Z TODAY ACROSS WEST CENTRAL AND
SOUTHWEST WY INCLUDING KJAC AND KAFO AS BEST FORCING AND JET ENERGY
PUSH ACROSS WYOMING. HOWEVER...MAINLY SNOW SHOWERS WILL CONTINUE
ACROSS NORTHWEST WY INCLUDING YELLOWSTONE PARK AS SNOW LEVELS DROP
TO 6500 FEET THROUGH THIS EVENING AS MOISTURE WRAPS AROUND THE
CIRCULATION NOW OVER IDAHO THAT WILL TRACK TO MT. MOUNTAIN TOP
OBSCURATIONS WILL BE WIDESPREAD THROUGH ABOUT 21Z-23Z BEFORE TROUGH
AND ASSOCIATED COLD FRONT SWING EAST OF KJAC BUT WILL LINGER THROUGH
06Z AT YNP. CANNOT RULE OUT A BRIEF PERIOD OF MVFR AT KJAC WITH A
HEAVIER RAIN SHOWER THROUGH 21Z TODAY. OTHERWISE...KJAC WILL REMAIN
VFR WITH RAPID CLEARING BETWEEN 23Z/TODAY AND 02Z/WED. OTHER TERMINALS
WILL ALL BE VFR THROUGH THE PERIOD. EXPECT ENOUGH INSTABILITY AND
MOISTURE TO GENERATE CONVECTION ACROSS SOUTHWEST WYOMING...MAINLY
AFFECTING KBPI...KPNA...AND KRKS TERMINALS FOR THE NEXT HOUR OR TWO.
MUCH MORE ISOLATED CONVECTION ELSEWHERE. LARGER ISSUE EAST OF THE
DIVIDE WILL BE DOWNSLOPE WINDS NEAR THE MOUNTAINS AND FOOTHILLS AND
GUSTY SOUTH TO WEST SURFACE WIND. WINDS WILL BE 15-20KTS WITH GUSTS
25-35KTS. STRONGEST WIND WILL BE THROUGH 23Z THIS AFTERNOON AT KCPR
WHERE 25G35KTS IS LIKELY. TROUGH PASSAGE BETWEEN 00Z-06Z/WED WILL
VEER WINDS TO THE NORTHWEST WITH DECREASING SPEEDS AFTER SUNSET. THE
EXCEPTION WILL BE KRIW WHERE FAVORABLE NORTHWEST WIND OF 15-25KTS IS
LIKELY THROUGH ABOUT 06Z/WED. ALL TERMINALS WILL SEE RAPID CLEARING
FROM THE WEST BEGINNING AT 00Z/WED AND CONTINUING THROUGH 06Z/WED.

&&

.FIRE WEATHER...

ANOTHER UNSEASONABLY WARM AND WINDY DAY EAST OF THE DIVIDE WHILE A
STORM MOVES INTO THE WEST. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR
WETTING RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE
POTENTIAL ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE.
THERE COULD ALSO BE SOME WETTING RAINS IN RAWLINS DISPATCH AREA. A
COLD FRONT SWEEPS THROUGH TONIGHT...CHANGING THE WIND DIRECTION TO
MORE WESTERLY. THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY
WITH COOL TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON
THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE
ANOTHER BREEZY DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH
COMMON BETWEEN ROCK SPRINGS AND CASPER AND OVER THE HIGHER
ELEVATIONS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ/LIPSON
FIRE WEATHER...ALLEN














000
FXUS65 KRIW 210930
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
330 AM MDT TUE OCT 21 2014

.SHORT TERM...TODAY THROUGH THURSDAY NIGHT

SWIFT SOUTHWEST FLOW DEVELOPING TODAY AHEAD OF AN APPROACHING SHORT
WAVE TROUGH. WIND SPEEDS WILL BE ELEVATED BUT BELOW WARNING
CRITERIA...MAIN IMPACT WILL BE TO LIGHT TRAILERS AND HIGH PROFILE
VEHICLES...ESPECIALLY IN SWEETWATER COUNTY...SOUTHEAST FREMONT AND
NATRONA COUNTIES. LATER ON THIS EVENING...THE STRONGER WINDS WILL BE
FOUND ALONG THE ABSAROKAS AND INTO THE CODY FOOTHILLS...AND UPPER
WIND RIVER BASIN AS THE FLOW TURNS A LITTLE MORE WESTERLY
...INCREASING THE BREAKING MOUNTAIN WAVE THREAT. FLOW WILL LIKELY BE
TOO QUICK AND SOUTHWESTERLY AT FIRST AND WILL SAIL RIGHT OVER THE
BARRIER BUT THERE COULD BE SOME BREAKING ACTION EARLY IN THE
EVENING...ESPECIALLY IN WEST CODY AND AROUND CLARK AS WINDS VEER
MORE WESTERLY. THIS IS EXPECTED TO BE BRIEF AS THE SUBSIDENT LEFT
ENTRANCE REGION OF THE JET SAILS BY EARLY IN THE EVENING FOLLOWED BY
SOME BROAD BUT WEAKER FORCING FOR DESCENT BEHIND THE EXITING TROUGH.

WHILE THERE IS LIMITED MOISTURE WITH THIS SYSTEM THERE WILL BE AT
LEAST SOME RAIN AND SNOW...WITH ANY MEASURABLE PRECIPITATION
EXPECTED TO BE LIMITED TO AREAS ALONG AND WEST OF THE
DIVIDE...INCLUDING SWEETWATER COUNTY. DOWNSLOPING EAST OF THE DIVIDE
SHOULD LIMIT ANY PRECIPITATION THERE. THERE WILL BE SOME JET
ENERGY..WEAK INSTABILITY AND SOME QG FORCING HELPING TO MAXIMIZE THE
POTENTIAL OF THIS WAVE SO THERE COULD BE A FEW SHOWERS MAKE IT OVER
THE MOUNTAINS. RECENT MODEL RUNS HAVE TAKEN THE BULK OF THE ENERGY
FROM THIS WAVE A LITTLE FURTHER NORTH THAN PREVIOUS RUNS...BUT POPS
LARGELY LEFT ALONE...WITH SOME TRIMMING IN A FEW AREAS BUT OVERALL
NOT MUCH CHANGE IN CONTINUITY WITH PREVIOUS FORECAST.

THE MODELS HAVE ALSO BEEN BACKING OFF ON H7 TEMPERATURES ALONG AND
BEHIND THE COLD FRONT. SNOW LEVELS WILL NOW BE ONLY AS LOW AS 8KFT
ACROSS THE WESTERN MOUNTAINS LOWERING TO 6.5KFT THIS EVENING BEFORE
THE SYSTEM EXITS...HIGHER AS YOU HEAD EAST. THE FRONT EVENTUALLY
MAKES IT ALL THE WAY THROUGH THE STATE TONIGHT...WITH THE COOLER
AIRMASS HANGING AROUND INTO WEDNESDAY WITH SOME MODERATION ON
THURSDAY. THURSDAY COULD ALSO BE A BREEZY DAY AS A TUG OF WAR
BETWEEN THE COLD BUT DYNAMIC TROUGH TO OUR NORTH AND THE RIDGE
POKING IN FROM THE SOUTH. OVERALL IT LOOKS LIKE THE RIDGE WILL WIN
OUT IN OUR AREA WITH REBOUNDING TEMPERATURES EXPECTED.

.LONG TERM...FRIDAY THROUGH TUESDAY

SYNOPSIS...UNSEASONABLY MILD AND MAINLY DRY CONDITIONS WILL PREVAIL
FRIDAY AND SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE ACROSS
CENTRAL AND SOUTHERN WYOMING ALONG WITH BREEZY/WINDY AREAS.  A
TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT WILL PUSH ACROSS
WYOMING ON SUNDAY/SUNDAY NIGHT BRINGING CHANCES OF RAIN AND SNOW
SHOWERS.  A DRIER AND COOL AIRMASS WILL FOLLOW ON MONDAY.

DISCUSSION...UPPER LOW OVER SW ALASKA EARLY THIS MORNING IS FORECAST
TO WOBBLE SE ALONG THE COAST OF BRITISH COLUMBIA WITH UPPER TROUGH
SHARPENING AND BECOMING MORE UPRIGHT OFF THE WEST COAST ON
FRIDAY...PUMPING UP RIDGE OVER THE HIGH PLAINS.  MEDIUM-RANGE MODELS
IN GOOD AGREEMENT UP TO THIS POINT.  MODEL DIFFERENCES BECOME MORE
APPARENT AS THE TROUGH MAKES LANDFALL ALONG THE COAST FRIDAY NIGHT
AND SATURDAY WITH THE GFS SHEARING LEAD SHORTWAVE NE ACROSS
IDAHO/WESTERN MONTANA ON SATURDAY WHILE THE ECMWF SHOWS A SLOWER
MUCH MORE SPLIT TROUGH PUSHING ACROSS THE ROCKIES ON SUNDAY.  GFS
AND EC RESPECTIVE ENSEMBLE MEANS SUPPORT SLOWER OVERALL PROGRESSION
THAN GFS AND NOT AS MUCH SPLITTING AS ECMWF DETERMINISTIC GUIDANCE.
FORECAST LEANS TOWARD THE ENSEMBLE MEANS WITH COLD FRONT PUSHING
INTO THE WEST LATE SATURDAY/SATURDAY NIGHT WITH INCREASING POPS
ACROSS THE WEST AND SPREADING ACROSS CENTRAL AREAS SUNDAY AND SUNDAY
NIGHT.  GEFS MEAN KEEP THE BEST CHANCES OF PRECIPITATION NORTH AND
WEST OF WYOMING WITH DOWNSLOPE FLOW KEEPING CHANCES OF PRECIPITATION
LOW EAST OF THE DIVIDE.  ENSEMBLE MEANS ALSO SHOW HEIGHTS REBOUNDING
A BIT QUICKER MONDAY AS NEXT TROUGH APPROACHES THE NW COAST WITH
FLAT RIDGING OVER THE AREA ON TUESDAY.  FORECAST KEEPS LOW POPS OVER
THE MOUNTAINS ON MONDAY DRY AND SEASONABLY COOL TEMPERATURES ACROSS
THE BASINS AND VALLEYS.  MILDER...ABOVE NORMAL TEMPERATURES ARE
EXPECTED ON TUESDAY.

&&

.AVIATION.../12Z ISSUANCE/

SHORTWAVE APPROACHING SOUTHWEST IDAHO WILL SWING ACROSS NORTHWEST
WYOMING TODAY. CLOUD COVER AND SHOWERS WILL BE ON THE INCREASE
THROUGH 18Z TODAY AS BEST FORCING AND JET ENERGY PUSH ACROSS
NORTHWEST WYOMING. MOUNTAIN TOP OBSCURATIONS WILL BE WIDESPREAD
THROUGH ABOUT 21Z-23Z BEFORE TROUGH AND ASSOCIATED COLD FRONT SWING
EAST OF KJAC. COULD STILL SEE A BRIEF PERIOD OF MVFR AT KJAC WITH A
HEAVIER RAIN SHOWER BETWEEN 16Z-21Z TODAY. OTHERWISE...KJAC WILL
REMAIN VFR WITH RAPID CLEARING BETWEEN 23Z/TUE AND 02Z/WED. OTHER
TERMINALS WILL ALL BE VFR THROUGH THE PERIOD. EXPECT ENOUGH
INSTABILITY AND MOISTURE TO GENERATE CONVECTION ACROSS SOUTHWEST
WYOMING...MAINLY AFFECTING KBPI...KPNA...AND KRKS TERMINALS. MUCH
MORE ISOLATED CONVECTION ELSEWHERE. LARGER ISSUE EAST OF THE DIVIDE
WILL BE DOWNSLOPE WINDS NEAR THE MOUNTAINS AND FOOTHILLS AND GUSTY
SOUTH TO WEST SURFACE WIND. WINDS WILL BE 15-20KTS WITH GUSTS
25-35KTS. STRONGEST WIND WILL BE DURING THE MIDDAY HOURS AT KCPR
WHERE 25G35KTS IS LIKELY. TROUGH PASSAGE BETWEEN 00Z-06Z/WED WILL
VEER WINDS TO THE NORTHWEST WITH DECREASING SPEEDS AFTER SUNSET. THE
EXCEPTION WILL BE KRIW WHERE FAVORABLE NORTHWEST WIND OF 15-25KTS IS
LIKELY THROUGH ABOUT 06Z/WED. ALL TERMINALS WILL SEE RAPID CLEARING
FROM THE WEST BEGINNING AT 00Z/WED AND CONTINUING THROUGH 06Z/WED.

&&

.FIRE WEATHER...

ANOTHER UNSEASONABLY WARM AND WINDY DAY EAST OF THE DIVIDE WHILE A
STORM MOVES INTO THE WEST. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR
WETTING RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE
POTENTIAL ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE.
THERE COULD ALSO BE SOME WETTING RAINS IN RAWLINS DISPATCH AREA. A
COLD FRONT SWEEPS THROUGH TONIGHT...CHANGING THE WIND DIRECTION TO
MORE WESTERLY. THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY
WITH COOL TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON
THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE
ANOTHER BREEZY DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH
COMMON BETWEEN ROCK SPRINGS AND CASPER AND OVER THE HIGHER
ELEVATIONS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ
FIRE WEATHER...ALLEN










000
FXUS65 KRIW 210930
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
330 AM MDT TUE OCT 21 2014

.SHORT TERM...TODAY THROUGH THURSDAY NIGHT

SWIFT SOUTHWEST FLOW DEVELOPING TODAY AHEAD OF AN APPROACHING SHORT
WAVE TROUGH. WIND SPEEDS WILL BE ELEVATED BUT BELOW WARNING
CRITERIA...MAIN IMPACT WILL BE TO LIGHT TRAILERS AND HIGH PROFILE
VEHICLES...ESPECIALLY IN SWEETWATER COUNTY...SOUTHEAST FREMONT AND
NATRONA COUNTIES. LATER ON THIS EVENING...THE STRONGER WINDS WILL BE
FOUND ALONG THE ABSAROKAS AND INTO THE CODY FOOTHILLS...AND UPPER
WIND RIVER BASIN AS THE FLOW TURNS A LITTLE MORE WESTERLY
...INCREASING THE BREAKING MOUNTAIN WAVE THREAT. FLOW WILL LIKELY BE
TOO QUICK AND SOUTHWESTERLY AT FIRST AND WILL SAIL RIGHT OVER THE
BARRIER BUT THERE COULD BE SOME BREAKING ACTION EARLY IN THE
EVENING...ESPECIALLY IN WEST CODY AND AROUND CLARK AS WINDS VEER
MORE WESTERLY. THIS IS EXPECTED TO BE BRIEF AS THE SUBSIDENT LEFT
ENTRANCE REGION OF THE JET SAILS BY EARLY IN THE EVENING FOLLOWED BY
SOME BROAD BUT WEAKER FORCING FOR DESCENT BEHIND THE EXITING TROUGH.

WHILE THERE IS LIMITED MOISTURE WITH THIS SYSTEM THERE WILL BE AT
LEAST SOME RAIN AND SNOW...WITH ANY MEASURABLE PRECIPITATION
EXPECTED TO BE LIMITED TO AREAS ALONG AND WEST OF THE
DIVIDE...INCLUDING SWEETWATER COUNTY. DOWNSLOPING EAST OF THE DIVIDE
SHOULD LIMIT ANY PRECIPITATION THERE. THERE WILL BE SOME JET
ENERGY..WEAK INSTABILITY AND SOME QG FORCING HELPING TO MAXIMIZE THE
POTENTIAL OF THIS WAVE SO THERE COULD BE A FEW SHOWERS MAKE IT OVER
THE MOUNTAINS. RECENT MODEL RUNS HAVE TAKEN THE BULK OF THE ENERGY
FROM THIS WAVE A LITTLE FURTHER NORTH THAN PREVIOUS RUNS...BUT POPS
LARGELY LEFT ALONE...WITH SOME TRIMMING IN A FEW AREAS BUT OVERALL
NOT MUCH CHANGE IN CONTINUITY WITH PREVIOUS FORECAST.

THE MODELS HAVE ALSO BEEN BACKING OFF ON H7 TEMPERATURES ALONG AND
BEHIND THE COLD FRONT. SNOW LEVELS WILL NOW BE ONLY AS LOW AS 8KFT
ACROSS THE WESTERN MOUNTAINS LOWERING TO 6.5KFT THIS EVENING BEFORE
THE SYSTEM EXITS...HIGHER AS YOU HEAD EAST. THE FRONT EVENTUALLY
MAKES IT ALL THE WAY THROUGH THE STATE TONIGHT...WITH THE COOLER
AIRMASS HANGING AROUND INTO WEDNESDAY WITH SOME MODERATION ON
THURSDAY. THURSDAY COULD ALSO BE A BREEZY DAY AS A TUG OF WAR
BETWEEN THE COLD BUT DYNAMIC TROUGH TO OUR NORTH AND THE RIDGE
POKING IN FROM THE SOUTH. OVERALL IT LOOKS LIKE THE RIDGE WILL WIN
OUT IN OUR AREA WITH REBOUNDING TEMPERATURES EXPECTED.

.LONG TERM...FRIDAY THROUGH TUESDAY

SYNOPSIS...UNSEASONABLY MILD AND MAINLY DRY CONDITIONS WILL PREVAIL
FRIDAY AND SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE ACROSS
CENTRAL AND SOUTHERN WYOMING ALONG WITH BREEZY/WINDY AREAS.  A
TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT WILL PUSH ACROSS
WYOMING ON SUNDAY/SUNDAY NIGHT BRINGING CHANCES OF RAIN AND SNOW
SHOWERS.  A DRIER AND COOL AIRMASS WILL FOLLOW ON MONDAY.

DISCUSSION...UPPER LOW OVER SW ALASKA EARLY THIS MORNING IS FORECAST
TO WOBBLE SE ALONG THE COAST OF BRITISH COLUMBIA WITH UPPER TROUGH
SHARPENING AND BECOMING MORE UPRIGHT OFF THE WEST COAST ON
FRIDAY...PUMPING UP RIDGE OVER THE HIGH PLAINS.  MEDIUM-RANGE MODELS
IN GOOD AGREEMENT UP TO THIS POINT.  MODEL DIFFERENCES BECOME MORE
APPARENT AS THE TROUGH MAKES LANDFALL ALONG THE COAST FRIDAY NIGHT
AND SATURDAY WITH THE GFS SHEARING LEAD SHORTWAVE NE ACROSS
IDAHO/WESTERN MONTANA ON SATURDAY WHILE THE ECMWF SHOWS A SLOWER
MUCH MORE SPLIT TROUGH PUSHING ACROSS THE ROCKIES ON SUNDAY.  GFS
AND EC RESPECTIVE ENSEMBLE MEANS SUPPORT SLOWER OVERALL PROGRESSION
THAN GFS AND NOT AS MUCH SPLITTING AS ECMWF DETERMINISTIC GUIDANCE.
FORECAST LEANS TOWARD THE ENSEMBLE MEANS WITH COLD FRONT PUSHING
INTO THE WEST LATE SATURDAY/SATURDAY NIGHT WITH INCREASING POPS
ACROSS THE WEST AND SPREADING ACROSS CENTRAL AREAS SUNDAY AND SUNDAY
NIGHT.  GEFS MEAN KEEP THE BEST CHANCES OF PRECIPITATION NORTH AND
WEST OF WYOMING WITH DOWNSLOPE FLOW KEEPING CHANCES OF PRECIPITATION
LOW EAST OF THE DIVIDE.  ENSEMBLE MEANS ALSO SHOW HEIGHTS REBOUNDING
A BIT QUICKER MONDAY AS NEXT TROUGH APPROACHES THE NW COAST WITH
FLAT RIDGING OVER THE AREA ON TUESDAY.  FORECAST KEEPS LOW POPS OVER
THE MOUNTAINS ON MONDAY DRY AND SEASONABLY COOL TEMPERATURES ACROSS
THE BASINS AND VALLEYS.  MILDER...ABOVE NORMAL TEMPERATURES ARE
EXPECTED ON TUESDAY.

&&

.AVIATION.../12Z ISSUANCE/

SHORTWAVE APPROACHING SOUTHWEST IDAHO WILL SWING ACROSS NORTHWEST
WYOMING TODAY. CLOUD COVER AND SHOWERS WILL BE ON THE INCREASE
THROUGH 18Z TODAY AS BEST FORCING AND JET ENERGY PUSH ACROSS
NORTHWEST WYOMING. MOUNTAIN TOP OBSCURATIONS WILL BE WIDESPREAD
THROUGH ABOUT 21Z-23Z BEFORE TROUGH AND ASSOCIATED COLD FRONT SWING
EAST OF KJAC. COULD STILL SEE A BRIEF PERIOD OF MVFR AT KJAC WITH A
HEAVIER RAIN SHOWER BETWEEN 16Z-21Z TODAY. OTHERWISE...KJAC WILL
REMAIN VFR WITH RAPID CLEARING BETWEEN 23Z/TUE AND 02Z/WED. OTHER
TERMINALS WILL ALL BE VFR THROUGH THE PERIOD. EXPECT ENOUGH
INSTABILITY AND MOISTURE TO GENERATE CONVECTION ACROSS SOUTHWEST
WYOMING...MAINLY AFFECTING KBPI...KPNA...AND KRKS TERMINALS. MUCH
MORE ISOLATED CONVECTION ELSEWHERE. LARGER ISSUE EAST OF THE DIVIDE
WILL BE DOWNSLOPE WINDS NEAR THE MOUNTAINS AND FOOTHILLS AND GUSTY
SOUTH TO WEST SURFACE WIND. WINDS WILL BE 15-20KTS WITH GUSTS
25-35KTS. STRONGEST WIND WILL BE DURING THE MIDDAY HOURS AT KCPR
WHERE 25G35KTS IS LIKELY. TROUGH PASSAGE BETWEEN 00Z-06Z/WED WILL
VEER WINDS TO THE NORTHWEST WITH DECREASING SPEEDS AFTER SUNSET. THE
EXCEPTION WILL BE KRIW WHERE FAVORABLE NORTHWEST WIND OF 15-25KTS IS
LIKELY THROUGH ABOUT 06Z/WED. ALL TERMINALS WILL SEE RAPID CLEARING
FROM THE WEST BEGINNING AT 00Z/WED AND CONTINUING THROUGH 06Z/WED.

&&

.FIRE WEATHER...

ANOTHER UNSEASONABLY WARM AND WINDY DAY EAST OF THE DIVIDE WHILE A
STORM MOVES INTO THE WEST. DOWNSLOPING WINDS WILL LIMIT CHANCES FOR
WETTING RAIN EAST...WHILE MORE FAVORABLE FLOW WILL MAXIMIZE
POTENTIAL ALONG WEST FACING SLOPES ALONG AND WEST OF THE DIVIDE.
THERE COULD ALSO BE SOME WETTING RAINS IN RAWLINS DISPATCH AREA. A
COLD FRONT SWEEPS THROUGH TONIGHT...CHANGING THE WIND DIRECTION TO
MORE WESTERLY. THE WIND AND THE RAIN WILL CLEAR OUT ON WEDNESDAY
WITH COOL TEMPERATURES REMAINING. TEMPERATURES REBOUND A BIT ON
THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE SOUTH BUT IT WILL BE
ANOTHER BREEZY DAY IN SPOTS WITH SOUTHWEST WINDS OF 15 TO 25 MPH
COMMON BETWEEN ROCK SPRINGS AND CASPER AND OVER THE HIGHER
ELEVATIONS.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ
FIRE WEATHER...ALLEN











000
FXUS65 KRIW 210524
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1124 PM MDT MON OCT 20 2014

.SHORT TERM...TONIGHT THROUGH TUESDAY

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC
TROUGH MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA.  THIS WILL BRING INCREASING SOUTHWEST FLOW
ALOFT...INSTABILITY AND MOISTURE TO THE AREA AS THE TROUGH
APPROACHES WESTERN WYOMING.  WINDS WILL INCREASE TONIGHT AND TUESDAY
BECOMING WINDY OVER AND NEAR THE MOUNTAINS AND THROUGH THE WIND
CORRIDOR. SOME GUSTS TO 45 MPH CAN BE EXPECTED FROM ROCK SPRINGS
THROUGH SOUTH PASS TO CASPER...AND IN THE CODY FOOTHILLS. SHOWERS
AND CLOUDS WILL INCREASE OVER THE WEST LATER TONIGHT AND BECOME MORE
WIDESPREAD OVER THE MOUNTAINS THROUGH TUESDAY. ISOLATED
THUNDERSTORMS CANNOT BE RULED OUT WITH MARGINAL INSTABILITY AND
INCREASING JET DYNAMICS OVER THE AREA. THE LOWER ELEVATIONS EAST OF
THE CONTINENTAL DIVIDE SHOULD REMAIN DRY BUT WILL SEE MORE CLOUD
COVER BRINGING SOME COOLING.

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

THE APPROACHING TROUGH ON TUESDAY LOOKS TO SPLIT AS IT MOVES ACROSS
THE CWA ON TUESDAY EVENING. AS THE SYSTEM SPLITS...THE SEGMENTS OF
PRECIPITATION WILL MOVE TO THE NORTH AND SOUTH BRINGING DRYING
CONDITIONS ACROSS THE FORECAST AREA BY WEDNESDAY MORNING. A BUILDING
RIDGE WILL KEEP QUIET CONDITIONS OVER THE AREA FOR THE NEXT SEVERAL
DAYS.

TEMPERATURES WILL WARM UNDER THE APPROACHING TROUGH...AND SOME AREAS
OF PRECIPITATION WILL APPROACH THE FORECAST AREA FROM THE WEST. A
FEW ROGUE SHOWERS MAY BE POSSIBLE THROUGH THE REST OF THE
WEEK...THOUGH THE DRY CONDITIONS ARE EXPECTED TO REMAIN PREVALENT
THROUGH SATURDAY. AN APPROACHING TROUGH OF LOW PRESSURE WILL MOVE
OFF THE PACIFIC COAST SATURDAY AND BEGIN TO MOVE EAST TOWARDS THE
FORECAST AREA.

THE TROUGH WILL BEGIN TO INFLUENCE THE FORECAST AREA EARLY
SUNDAY...POTENTIALLY SPREADING SHOWER ACTIVITY ACROSS MUCH OF
WESTERN AND CENTRAL WYOMING THROUGH SUNDAY AFTERNOON. COOLER
TEMPERATURES WILL ALSO BE FOUND WITH THIS SYSTEM AS IT USHERS IN
COOLER H7 TEMPERATURES. THE TROUGH WILL MOVE QUICKLY THROUGH THE
FORECAST AREA...WITH A RETURN OF NORTHWEST FLOW ANTICIPATED BY
MONDAY AFTERNOON.

.AVIATION.../06Z ISSUANCE/
BOTH THE GFS AND NAM ADVERTISING THAT THE UPPER LOW OVER NORTHERN
CALIFORNIA WILL TRACK NORTHEAST AND SWING ACROSS NORTHWEST WYOMING
TODAY. JET ENERGY AND APPROACH OF THE SHORTWAVE WILL ASSIST
DEVELOPMENT OF RAIN/SNOW SHOWERS ACROSS THE NORTHWEST AFTER ABOUT
12Z-14Z TODAY. EXPECT WIDESPREAD MOUNTAIN TOP OBSCURATIONS ACROSS
THE NORTHWEST BETWEEN 12Z-23Z. COULD BE BRIEF PERIOD OF MVFR WITH
HEAVIER RAIN SHOWERS AT KJAC BETWEEN 16Z-21Z AS COLD FRONT PUSHES
THROUGH THE FAR WEST. OTHERWISE...KJAC WILL STAY VFR THROUGH THE
PERIOD WITH CLEARING SKIES AFTER 00Z/WED. CONVECTIVE SHOWERS WILL
BREAK OUT AHEAD OF THE COLD FRONT EARLY THIS AFTERNOON. BEST CHANCE
WILL BE ACROSS THE SOUTHWEST TERMINALS OF KBPI...KPNA...AND KRKS.
STILL...ALL OTHER TERMINALS WILL REMAIN VFR. WE HAVE TRENDED BACK ON
LOWER CIGS AND VSBYS AS THE BEST ENERGY STAYS NORTH OF THIS REGION.
BIGGER ISSUE EAST OF THE DIVIDE WILL BE GUSTY SOUTH TO WEST WIND
AHEAD OF THE COLD FRONT. SURFACE WIND OF 15-20KTS WILL BE COMMON
WITH GUSTS 25-35 KTS AT MANY TERMINALS. WINDS WILL DECREASE AND
BECOME MORE WEST TO NORTHWEST AFTER 00Z/WED AS THE TROUGH PUSHES
EAST THROUGH THE FORECAST AREA. THE EXCEPTION WILL BE KRIW WHERE
FAVORABLE NORTHWEST FLOW WILL PRODUCE A PERIOD OF POST-TROUGH WIND
15-25KTS THROUGH 06Z/WED.


.FIRE WEATHER...

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC
TROUGH MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA.  THIS WILL BRING INCREASING SOUTHWEST FLOW
ALOFT...INSTABILITY AND MOISTURE TO THE AREA AS THE TROUGH
APPROACHES WESTERN WYOMING.  WINDS WILL INCREASE TONIGHT AND TUESDAY
BECOMING WINDY OVER AND NEAR THE MOUNTAINS AND THROUGH THE WIND
CORRIDOR. SOME GUSTS TO 45 MPH CAN BE EXPECTED FROM ROCK SPRINGS
THROUGH SOUTH PASS TO CASPER...AND IN THE CODY FOOTHILLS. SHOWERS
AND CLOUDS WILL INCREASE OVER THE WEST LATER TONIGHT AND BECOME MORE
WIDESPREAD OVER THE MOUNTAINS THROUGH TUESDAY. ISOLATED
THUNDERSTORMS CANNOT BE RULED OUT WITH MARGINAL INSTABILITY AND
INCREASING JET DYNAMICS OVER THE AREA. RELATIVE HUMIDITY WILL
INCREASE ALONG WITH THE CLOUDS AND SHOWERS. THE LOWER ELEVATIONS
EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN DRY BUT WILL SEE MORE
CLOUD COVER BRINGING SOME COOLING.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRANHAM
AVIATION...CNJ
FIRE WEATHER...C.BAKER










000
FXUS65 KRIW 210524
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1124 PM MDT MON OCT 20 2014

.SHORT TERM...TONIGHT THROUGH TUESDAY

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC
TROUGH MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA.  THIS WILL BRING INCREASING SOUTHWEST FLOW
ALOFT...INSTABILITY AND MOISTURE TO THE AREA AS THE TROUGH
APPROACHES WESTERN WYOMING.  WINDS WILL INCREASE TONIGHT AND TUESDAY
BECOMING WINDY OVER AND NEAR THE MOUNTAINS AND THROUGH THE WIND
CORRIDOR. SOME GUSTS TO 45 MPH CAN BE EXPECTED FROM ROCK SPRINGS
THROUGH SOUTH PASS TO CASPER...AND IN THE CODY FOOTHILLS. SHOWERS
AND CLOUDS WILL INCREASE OVER THE WEST LATER TONIGHT AND BECOME MORE
WIDESPREAD OVER THE MOUNTAINS THROUGH TUESDAY. ISOLATED
THUNDERSTORMS CANNOT BE RULED OUT WITH MARGINAL INSTABILITY AND
INCREASING JET DYNAMICS OVER THE AREA. THE LOWER ELEVATIONS EAST OF
THE CONTINENTAL DIVIDE SHOULD REMAIN DRY BUT WILL SEE MORE CLOUD
COVER BRINGING SOME COOLING.

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

THE APPROACHING TROUGH ON TUESDAY LOOKS TO SPLIT AS IT MOVES ACROSS
THE CWA ON TUESDAY EVENING. AS THE SYSTEM SPLITS...THE SEGMENTS OF
PRECIPITATION WILL MOVE TO THE NORTH AND SOUTH BRINGING DRYING
CONDITIONS ACROSS THE FORECAST AREA BY WEDNESDAY MORNING. A BUILDING
RIDGE WILL KEEP QUIET CONDITIONS OVER THE AREA FOR THE NEXT SEVERAL
DAYS.

TEMPERATURES WILL WARM UNDER THE APPROACHING TROUGH...AND SOME AREAS
OF PRECIPITATION WILL APPROACH THE FORECAST AREA FROM THE WEST. A
FEW ROGUE SHOWERS MAY BE POSSIBLE THROUGH THE REST OF THE
WEEK...THOUGH THE DRY CONDITIONS ARE EXPECTED TO REMAIN PREVALENT
THROUGH SATURDAY. AN APPROACHING TROUGH OF LOW PRESSURE WILL MOVE
OFF THE PACIFIC COAST SATURDAY AND BEGIN TO MOVE EAST TOWARDS THE
FORECAST AREA.

THE TROUGH WILL BEGIN TO INFLUENCE THE FORECAST AREA EARLY
SUNDAY...POTENTIALLY SPREADING SHOWER ACTIVITY ACROSS MUCH OF
WESTERN AND CENTRAL WYOMING THROUGH SUNDAY AFTERNOON. COOLER
TEMPERATURES WILL ALSO BE FOUND WITH THIS SYSTEM AS IT USHERS IN
COOLER H7 TEMPERATURES. THE TROUGH WILL MOVE QUICKLY THROUGH THE
FORECAST AREA...WITH A RETURN OF NORTHWEST FLOW ANTICIPATED BY
MONDAY AFTERNOON.

.AVIATION.../06Z ISSUANCE/
BOTH THE GFS AND NAM ADVERTISING THAT THE UPPER LOW OVER NORTHERN
CALIFORNIA WILL TRACK NORTHEAST AND SWING ACROSS NORTHWEST WYOMING
TODAY. JET ENERGY AND APPROACH OF THE SHORTWAVE WILL ASSIST
DEVELOPMENT OF RAIN/SNOW SHOWERS ACROSS THE NORTHWEST AFTER ABOUT
12Z-14Z TODAY. EXPECT WIDESPREAD MOUNTAIN TOP OBSCURATIONS ACROSS
THE NORTHWEST BETWEEN 12Z-23Z. COULD BE BRIEF PERIOD OF MVFR WITH
HEAVIER RAIN SHOWERS AT KJAC BETWEEN 16Z-21Z AS COLD FRONT PUSHES
THROUGH THE FAR WEST. OTHERWISE...KJAC WILL STAY VFR THROUGH THE
PERIOD WITH CLEARING SKIES AFTER 00Z/WED. CONVECTIVE SHOWERS WILL
BREAK OUT AHEAD OF THE COLD FRONT EARLY THIS AFTERNOON. BEST CHANCE
WILL BE ACROSS THE SOUTHWEST TERMINALS OF KBPI...KPNA...AND KRKS.
STILL...ALL OTHER TERMINALS WILL REMAIN VFR. WE HAVE TRENDED BACK ON
LOWER CIGS AND VSBYS AS THE BEST ENERGY STAYS NORTH OF THIS REGION.
BIGGER ISSUE EAST OF THE DIVIDE WILL BE GUSTY SOUTH TO WEST WIND
AHEAD OF THE COLD FRONT. SURFACE WIND OF 15-20KTS WILL BE COMMON
WITH GUSTS 25-35 KTS AT MANY TERMINALS. WINDS WILL DECREASE AND
BECOME MORE WEST TO NORTHWEST AFTER 00Z/WED AS THE TROUGH PUSHES
EAST THROUGH THE FORECAST AREA. THE EXCEPTION WILL BE KRIW WHERE
FAVORABLE NORTHWEST FLOW WILL PRODUCE A PERIOD OF POST-TROUGH WIND
15-25KTS THROUGH 06Z/WED.


.FIRE WEATHER...

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC
TROUGH MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN
CALIFORNIA.  THIS WILL BRING INCREASING SOUTHWEST FLOW
ALOFT...INSTABILITY AND MOISTURE TO THE AREA AS THE TROUGH
APPROACHES WESTERN WYOMING.  WINDS WILL INCREASE TONIGHT AND TUESDAY
BECOMING WINDY OVER AND NEAR THE MOUNTAINS AND THROUGH THE WIND
CORRIDOR. SOME GUSTS TO 45 MPH CAN BE EXPECTED FROM ROCK SPRINGS
THROUGH SOUTH PASS TO CASPER...AND IN THE CODY FOOTHILLS. SHOWERS
AND CLOUDS WILL INCREASE OVER THE WEST LATER TONIGHT AND BECOME MORE
WIDESPREAD OVER THE MOUNTAINS THROUGH TUESDAY. ISOLATED
THUNDERSTORMS CANNOT BE RULED OUT WITH MARGINAL INSTABILITY AND
INCREASING JET DYNAMICS OVER THE AREA. RELATIVE HUMIDITY WILL
INCREASE ALONG WITH THE CLOUDS AND SHOWERS. THE LOWER ELEVATIONS
EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN DRY BUT WILL SEE MORE
CLOUD COVER BRINGING SOME COOLING.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRANHAM
AVIATION...CNJ
FIRE WEATHER...C.BAKER











000
FXUS65 KRIW 202126
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
326 PM MDT MON OCT 20 2014

.SHORT TERM...TONIGHT THROUGH TUESDAY

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

THE APPROACHING TROUGH ON TUESDAY LOOKS TO SPLIT AS IT MOVES ACROSS
THE CWA ON TUESDAY EVENING. AS THE SYSTEM SPLITS...THE SEGMENTS OF
PRECIPITATION WILL MOVE TO THE NORTH AND SOUTH BRINGING DRYING
CONDITIONS ACROSS THE FORECAST AREA BY WEDNESDAY MORNING. A BUILDING
RIDGE WILL KEEP QUIET CONDITIONS OVER THE AREA FOR THE NEXT SEVERAL
DAYS.

TEMPERATURES WILL WARM UNDER THE APPROACHING TROUGH...AND SOME AREAS
OF PRECIPITATION WILL APPROACH THE FORECAST AREA FROM THE WEST. A
FEW ROGUE SHOWERS MAY BE POSSIBLE THROUGH THE REST OF THE
WEEK...THOUGH THE DRY CONDITIONS ARE EXPECTED TO REMAIN PREVALENT
THROUGH SATURDAY. AN APPROACHING TROUGH OF LOW PRESSURE WILL MOVE
OFF THE PACIFIC COAST SATURDAY AND BEGIN TO MOVE EAST TOWARDS THE
FORECAST AREA.

THE TROUGH WILL BEGIN TO INFLUENCE THE FORECAST AREA EARLY
SUNDAY...POTENTIALLY SPREADING SHOWER ACTIVITY ACROSS MUCH OF
WESTERN AND CENTRAL WYOMING THROUGH SUNDAY AFTERNOON. COOLER
TEMPERATURES WILL ALSO BE FOUND WITH THIS SYSTEM AS IT USHERS IN
COOLER H7 TEMPERATURES. THE TROUGH WILL MOVE QUICKLY THROUGH THE
FORECAST AREA...WITH A RETURN OF NORTHWEST FLOW ANTICIPATED BY
MONDAY AFTERNOON.

.AVIATION.../00Z ISSUANCE/

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 18Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS...ALONG
AND EAST OF THE CONTINENTAL DIVIDE AFTER 10Z. AREAS OF MVFR TO IFR
CEILINGS AND VISIBILITIES...WILL DEVELOP DURING THIS
TIME...OBSCURING THE HIGHER MOUNTAINS. STRONG WEST TO SOUTHWEST
WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND CLOUDS...BECOMING
25-30KTS WITH GUSTS TO 40KTS ALONG AND NEAR THE EAST SLOPES OF THE
MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM KRKS TO KCPR.

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 10Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS AND FAR
WESTERN VALLEYS AFTER 07Z. AREAS OF MVFR TO IFR CEILINGS AND
VISIBILITIES...WILL DEVELOP DURING THIS TIME...OBSCURING THE HIGHER
MOUNTAINS. BRIEF MVFR CONDITIONS MAY OCCUR AT KJAC...KBPI AND KPNA
AFTER 10Z...WITH IMPROVING CONDITIONS BY 22Z. STRONG WEST TO
SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND
CLOUDS...BECOMING 20-25KTS WITH GUSTS TO 35KTS OVER THE MOUNTAINS
AND THROUGH THE I-80 CORRIDOR FROM KEVW TO KRKS.

.FIRE WEATHER...

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
RELATIVE HUMIDITY WILL INCREASE ALONG WITH THE CLOUDS AND SHOWERS.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRANHAM
AVIATION...LAVOIE
FIRE WEATHER...C.BAKER







000
FXUS65 KRIW 202126
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
326 PM MDT MON OCT 20 2014

.SHORT TERM...TONIGHT THROUGH TUESDAY

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

THE APPROACHING TROUGH ON TUESDAY LOOKS TO SPLIT AS IT MOVES ACROSS
THE CWA ON TUESDAY EVENING. AS THE SYSTEM SPLITS...THE SEGMENTS OF
PRECIPITATION WILL MOVE TO THE NORTH AND SOUTH BRINGING DRYING
CONDITIONS ACROSS THE FORECAST AREA BY WEDNESDAY MORNING. A BUILDING
RIDGE WILL KEEP QUIET CONDITIONS OVER THE AREA FOR THE NEXT SEVERAL
DAYS.

TEMPERATURES WILL WARM UNDER THE APPROACHING TROUGH...AND SOME AREAS
OF PRECIPITATION WILL APPROACH THE FORECAST AREA FROM THE WEST. A
FEW ROGUE SHOWERS MAY BE POSSIBLE THROUGH THE REST OF THE
WEEK...THOUGH THE DRY CONDITIONS ARE EXPECTED TO REMAIN PREVALENT
THROUGH SATURDAY. AN APPROACHING TROUGH OF LOW PRESSURE WILL MOVE
OFF THE PACIFIC COAST SATURDAY AND BEGIN TO MOVE EAST TOWARDS THE
FORECAST AREA.

THE TROUGH WILL BEGIN TO INFLUENCE THE FORECAST AREA EARLY
SUNDAY...POTENTIALLY SPREADING SHOWER ACTIVITY ACROSS MUCH OF
WESTERN AND CENTRAL WYOMING THROUGH SUNDAY AFTERNOON. COOLER
TEMPERATURES WILL ALSO BE FOUND WITH THIS SYSTEM AS IT USHERS IN
COOLER H7 TEMPERATURES. THE TROUGH WILL MOVE QUICKLY THROUGH THE
FORECAST AREA...WITH A RETURN OF NORTHWEST FLOW ANTICIPATED BY
MONDAY AFTERNOON.

.AVIATION.../00Z ISSUANCE/

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 18Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS...ALONG
AND EAST OF THE CONTINENTAL DIVIDE AFTER 10Z. AREAS OF MVFR TO IFR
CEILINGS AND VISIBILITIES...WILL DEVELOP DURING THIS
TIME...OBSCURING THE HIGHER MOUNTAINS. STRONG WEST TO SOUTHWEST
WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND CLOUDS...BECOMING
25-30KTS WITH GUSTS TO 40KTS ALONG AND NEAR THE EAST SLOPES OF THE
MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM KRKS TO KCPR.

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 10Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS AND FAR
WESTERN VALLEYS AFTER 07Z. AREAS OF MVFR TO IFR CEILINGS AND
VISIBILITIES...WILL DEVELOP DURING THIS TIME...OBSCURING THE HIGHER
MOUNTAINS. BRIEF MVFR CONDITIONS MAY OCCUR AT KJAC...KBPI AND KPNA
AFTER 10Z...WITH IMPROVING CONDITIONS BY 22Z. STRONG WEST TO
SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND
CLOUDS...BECOMING 20-25KTS WITH GUSTS TO 35KTS OVER THE MOUNTAINS
AND THROUGH THE I-80 CORRIDOR FROM KEVW TO KRKS.

.FIRE WEATHER...

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
RELATIVE HUMIDITY WILL INCREASE ALONG WITH THE CLOUDS AND SHOWERS.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRANHAM
AVIATION...LAVOIE
FIRE WEATHER...C.BAKER








000
FXUS65 KRIW 202114
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
314 PM MDT MON OCT 20 2014

.SHORT TERM...TONIGHT THROUGH TUESDAY

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY

NO MAJOR CHANGES IN THE FORECAST PACKAGE WITH THE 12Z RUNS OF THE
GFS AND ECMWF TODAY. A RIDGE CONTINUES TO BUILD OVER THE NORTHERN
ROCKIES AND NORTHERN PLAINS BY WEDNESDAY...IN RESPONSE TO A CLOSED
LOW MOVING ONSHORE OVER THE PACIFIC NORTHWEST. THERE ARE SOME TIMING
ISSUES BETWEEN THE GFS AND ECMWF...BUT BOTH MODELS FORECAST THIS
SYSTEM TO MOVE INTO SOUTHERN ALBERTA. WARM...BREEZY SOUTHWEST WINDS
WILL BE THE RESULT FOR THE FORECAST AREA FROM THIS SYSTEM. THE COLD
FRONT ASSOCIATED WITH THIS SYSTEM...WILL BECOME STATIONARY ACROSS
CENTRAL PORTIONS...EXTENDING FROM SHERIDAN COUNTY TO EASTERN
SWEETWATER COUNTY BY THURSDAY AFTERNOON. ANY CONVECTIVE ACTIVITY
GENERATED BY THIS BOUNDARY WILL BE ISOLATED AT BEST...DUE TO LIMITED
MOISTURE.

THIS WILL BE SHORT-LIVED...AS THE REMNANTS OF A TROPICAL SYSTEM
QUICKLY MOVES NORTHWARD OVER THE FOUR CORNERS AREA THURSDAY
AFTERNOON...AND INTO WYOMING BY NOON FRIDAY. EVEN WITH INCREASED
CLOUD COVER...THERE SHOULD BE ENOUGH INSTABILITY FOR CONVECTION TO
DEVELOP. HAVE BROAD BRUSHED POPS ACROSS THE FORECAST AREA...BUT
STRONGER STORMS SHOULD BE CONFINED ACROSS EASTERN AND CENTRAL
PORTIONS.

AS THIS SYSTEM BEGINS TO EXIT EASTWARD OUT OF THE AREA...ANOTHER
TROUGH DIGS ALONG THE COAST AND MOVES ONSHORE OVER NORTHERN
CALIFORNIA SATURDAY MORNING. THERE WILL BE ENOUGH RESIDUAL MOISTURE
LEFT OVER FROM FRIDAY FOR ADDITIONAL THUNDERSTORMS...AS A WARM FRONT
ASSOCIATED WITH THE TROUGH MOVES NORTHWARD. MOIST SOUTHERLY FLOW
WILL OCCUR FOR SUNDAY...AS THE TROUGH SLOWLY MAKES ITS WAY ACROSS
THE GREAT BASIN.

&&

.AVIATION.../00Z ISSUANCE/

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 18Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS...ALONG
AND EAST OF THE CONTINENTAL DIVIDE AFTER 10Z. AREAS OF MVFR TO IFR
CEILINGS AND VISIBILITIES...WILL DEVELOP DURING THIS
TIME...OBSCURING THE HIGHER MOUNTAINS. STRONG WEST TO SOUTHWEST
WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND CLOUDS...BECOMING
25-30KTS WITH GUSTS TO 40KTS ALONG AND NEAR THE EAST SLOPES OF THE
MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM KRKS TO KCPR.

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS THROUGH 10Z
TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE TROUGH WILL BRING
INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER THE MOUNTAINS AND FAR
WESTERN VALLEYS AFTER 07Z. AREAS OF MVFR TO IFR CEILINGS AND
VISIBILITIES...WILL DEVELOP DURING THIS TIME...OBSCURING THE HIGHER
MOUNTAINS. BRIEF MVFR CONDITIONS MAY OCCUR AT KJAC...KBPI AND KPNA
AFTER 10Z...WITH IMPROVING CONDITIONS BY 22Z. STRONG WEST TO
SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND
CLOUDS...BECOMING 20-25KTS WITH GUSTS TO 35KTS OVER THE MOUNTAINS
AND THROUGH THE I-80 CORRIDOR FROM KEVW TO KRKS.

&&

.FIRE WEATHER...

THE UPPER LEVEL HIGH PRESSURE RIDGE THAT HAS BROUGHT MILD...DRY
AND STABLE CONDITIONS TO WESTERN AND CENTRAL WYOMING OVER THE WEEKEND
HAS SHIFTED EAST INTO THE GREAT PLAINS AS A FAST MOVING PACIFIC TROUGH
MOVES INLAND INTO THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
THIS WILL BRING INCREASING SOUTHWEST FLOW ALOFT...INSTABILITY AND
MOISTURE TO THE AREA AS THE TROUGH APPROACHES WESTERN WYOMING.  WINDS
WILL INCREASE TONIGHT AND TUESDAY BECOMING WINDY OVER AND NEAR THE MOUNTAINS
AND THROUGH THE WIND CORRIDOR. SOME GUSTS TO 45 MPH CAN BE
EXPECTED FROM ROCK SPRINGS THROUGH SOUTH PASS TO CASPER...AND IN
THE CODY FOOTHILLS. SHOWERS AND CLOUDS WILL INCREASE OVER THE WEST
LATER TONIGHT AND BECOME MORE WIDESPREAD OVER THE MOUNTAINS
THROUGH TUESDAY. ISOLATED THUNDERSTORMS CANNOT BE RULED OUT WITH
MARGINAL INSTABILITY AND INCREASING JET DYNAMICS OVER THE AREA.
RELATIVE HUMIDITY WILL INCREASE ALONG WITH THE CLOUDS AND SHOWERS.
THE LOWER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE SHOULD REMAIN
DRY BUT WILL SEE MORE CLOUD COVER BRINGING SOME COOLING.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRANHAM
AVIATION...LAVOIE
FIRE WEATHER...C.BAKER











000
FXUS65 KRIW 201743
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1143 AM MDT MON OCT 20 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

ONE MORE WARM DAY UNDERNEATH THE RIDGE TODAY AND TONIGHT
..TEMPERATURES WILL REMAIN 10 TO 15 DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR. A COLD FRONT WILL APPROACH THE WEST EARLY TUESDAY
MORNING...SWEEPING EAST THROUGH THE DAY. THE APPROACHING TROUGH
AND ASSOCIATED FRONT WILL CREATE A WINDY DAY FOR MUCH OF THE AREA
ON TUESDAY OTHERWISE THERE WILL BE A CHANCE FOR SOME RAIN...AND
SNOW ABOVE 6KFT RISING TO ABOUT 8.5KFT IN THE AFTERNOON...MAINLY
IN THE NORTHWESTERN MOUNTAINS AND YELLOWSTONE. SOME RAIN WILL BE
SPILLING ACROSS THE SOUTH AND INTO SOME AREAS EAST OF THE DIVIDE.
IT IS STARTING TO LOOK A BIT MORE UNSTABLE FOR TUESDAY AFTERNOON
THAN PREVIOUS RUNS...SO A SLIGHT CHANCE FOR THUNDER WAS INCLUDED
WITH THIS PACKAGE FOR THE 18Z TUE-00Z WED TIMEFRAME. THIS
INSTABILITY COULD HELP OVERCOME SOME OF THE DOWNSLOPING AFFECTS OF
THE SWIFT WEST AND SOUTHWEST FLOW...BRINGING A CHANCE FOR SOME
SHOWERS INTO THE FOOTHILLS AND BASINS EAST OF THE DIVIDE...KEPT
POPS QUIET FOR NOW BUT WOULD NOT BE SURPRISED IF A SHOWER OR TWO
MADE IT INTO THESE AREAS. THIS WILL NOT BE A SIGNIFICANT RAIN OR
SNOW PRODUCER BUT IT WILL COOL THINGS OFF A BIT...INCREASE CLOUD
COVER AND WIND SPEEDS ACROSS THE REGION TUESDAY AND TUESDAY
NIGHT...ESPECIALLY ALONG THE CODY FOOTHILLS AND THE UPPER WIND
RIVER BASIN OVERNIGHT AS THE SUBSIDENT BACK SIDE OF THE WAVE
PASSES OVERHEAD. THIS SHOULD HELP FORCE DOWN SOME STRONGER WIND
GUSTS INTO THE FOOTHILLS. CROSS SECTIONS ALONG THE ABSAROKAS SHOW
THE POTENTIAL FOR A BREAKING MOUNTAIN WAVE ALONG THE WESTERN CODY
FOOTHILLS OVERNIGHT...THIS WAVE COULD PRODUCE WIND GUSTS OVER 60
MPH AROUND CLARK AND WEST OF CODY. THE WAVE LIFTS OUT ON
WEDNESDAY...LEAVING BEHIND SOME COOLER BUT AVERAGE TEMPERATURES
FOR THIS TIME OF YEAR...AND SOME BREEZY WESTERLIES ACROSS THE
SOUTH.

.LONG TERM...THURSDAY THROUGH MONDAY

SYNOPSIS...UNSEASONABLY MILD AND DRY CONDITIONS WILL PREVAIL
THURSDAY THROUGH SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE
ON SATURDAY.  A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT
WILL MOVE ACROSS THE AREA SUNDAY AND MONDAY BRINGING A CHANCE OF
RAIN AND SNOW SHOWERS ALONG WITH COLDER TEMPERATURES.

DISCUSSION...UPPER HIGH STRENGTHENS OVER THE SOUTHERN ROCKIES
THURSDAY AND FRIDAY WITH BUILDING HEIGHTS ACROSS WYOMING WHILE
PACIFIC TROUGH SHARPENS NEAR 130W ON FRIDAY. UPPER TROUGH IS
FORECAST TO MAKE LANDFALL ALONG THE WEST COAST LATE SATURDAY WITH
LEAD SHORTWAVE EJECTING NE ACROSS THE INTERMOUNTAIN WEST INTO
SOUTHERN ALBERTA. THIS WILL BRING INCREASING SW FLOW ACROSS THE
AREA SATURDAY WITH LEE SIDE LOW DEVELOPMENT EXPECTED OVER CENTRAL
MONTANA PUTTING CENTRAL WYOMING IN WARM SECTOR. RECORD HIGH
TERRITORY FOR MANY LOCATIONS IS UPPER 60S TO LOWER 70S (73 AT
LND...72 AT CPR) SO THESE RECORDS WILL LIKELY BE IN JEOPARDY...AND
WITH GUSTY SOUTHWEST WIND...FIRE DANGER WILL BE ELEVATED.

GFS REMAINS MORE PROGRESSIVE THAN THE ECMWF BRINGING UPPER TROUGH
AND ASSOCIATED FRONT ACROSS THE AREA SUNDAY...AND 20/00Z ECMWF
DETERMINISTIC IS OUT AHEAD OF THE EC ENSEMBLE MEAN.  SO ALTHOUGH
AGREEMENT BETWEEN THE GFS AND ECMWF DETERMINISTIC RUNS IS MUCH
BETTER THIS MORNING...MEDIUM-RANGE MODELS HAVE YET TO SHOW ANY
DEGREE OF RUN-TO-RUN CONSISTENCY TO GAIN MUCH CONFIDENCE IN
TIMING OF COLD FRONT AND ONSET OF PRECIPITATION...WITH AN OVERALL
PREFERENCE TOWARD SLOWER PROGRESSION PER THE EC ENSEMBLE MEAN.
THIS RESULTS IN BRINGING CHANCES OF PRECIPITATION INTO THE WEST ON
SUNDAY AND SPREADING ACROSS THE AREA SUNDAY NIGHT INTO MONDAY.
TEMPERATURES ON MONDAY ARE EXPECTED TO BE SOME 20-25F COOLER THAN
NEAR RECORD HIGH TEMPERATURES ON SATURDAY...OR 5-10F BELOW NORMAL.

.AVIATION.../18Z ISSUANCE/

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS...INCLUDING
THE AIRPORTS THROUGH 18Z TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE
TROUGH WILL BRING INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER
THE MOUNTAINS ALONG AND EAST OF THE CONTINENTAL DIVIDE AFTER 10Z
WITH AREAS OF MVFR TO IFR CEILINGS...AND VISIBILITIES REDUCED IN
SHOWERS INCREASING AND OBSCURING THE HIGHER MOUNTAINS. STRONG
WEST TO SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND
CLOUDS BECOMING 25-30KTS WITH GUSTS TO 40KTS ALONG AND NEAR THE
EAST SLOPES OF THE MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM
KRKS TO KCPR.

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS...INCLUDING
THE AIRPORTS THROUGH 10Z TUESDAY. AN APPROACHING PACIFIC LOW
PRESSURE TROUGH WILL BRING INCREASED CLOUD COVER AND SHOWER
ACTIVITY OVER THE MOUNTAINS AND FAR WESTERN VALLEYS AFTER 07Z
WITH AREAS OF MVFR TO IFR CEILINGS...AND VISIBILITIES REDUCED IN
SHOWERS INCREASING AND OBSCURING THE HIGHER MOUNTAINS. BRIEF MVFR
CONDITIONS MAY OCCUR AT KJAC...KAFO...KEMM...KBPI AND KPNA AFTER
10Z. STRONG WEST TO SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE
SHOWERS AND CLOUDS BECOMING 20-25KTS WITH GUSTS TO 35KTS OVER THE
MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM KEVW TO KRKS.

.FIRE WEATHER...

SEASONABLY WARM TEMPERATURES AND LOW WIND SPEEDS CONTINUE AGAIN TODAY.
WHILE RELATIVE HUMIDITY VALUES MAY DIP INTO THE LOWER 20S OR EVEN
UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN ON THE LOW
SIDE...HELPING TO AVOID ENHANCED FIRE DANGER. HOWEVER...WIND SPEEDS
WILL INCREASE ON TUESDAY AHEAD OF THE NEXT STORM. CHANCES OF WETTING
RAIN WILL BE FAIRLY HIGH ACROSS THE HIGHER ELEVATIONS...THE WEST AND
ACROSS RAWLINS DISPATCH...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...C.BAKER
FIRE WEATHER...ALLEN









000
FXUS65 KRIW 201743
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1143 AM MDT MON OCT 20 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

ONE MORE WARM DAY UNDERNEATH THE RIDGE TODAY AND TONIGHT
..TEMPERATURES WILL REMAIN 10 TO 15 DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR. A COLD FRONT WILL APPROACH THE WEST EARLY TUESDAY
MORNING...SWEEPING EAST THROUGH THE DAY. THE APPROACHING TROUGH
AND ASSOCIATED FRONT WILL CREATE A WINDY DAY FOR MUCH OF THE AREA
ON TUESDAY OTHERWISE THERE WILL BE A CHANCE FOR SOME RAIN...AND
SNOW ABOVE 6KFT RISING TO ABOUT 8.5KFT IN THE AFTERNOON...MAINLY
IN THE NORTHWESTERN MOUNTAINS AND YELLOWSTONE. SOME RAIN WILL BE
SPILLING ACROSS THE SOUTH AND INTO SOME AREAS EAST OF THE DIVIDE.
IT IS STARTING TO LOOK A BIT MORE UNSTABLE FOR TUESDAY AFTERNOON
THAN PREVIOUS RUNS...SO A SLIGHT CHANCE FOR THUNDER WAS INCLUDED
WITH THIS PACKAGE FOR THE 18Z TUE-00Z WED TIMEFRAME. THIS
INSTABILITY COULD HELP OVERCOME SOME OF THE DOWNSLOPING AFFECTS OF
THE SWIFT WEST AND SOUTHWEST FLOW...BRINGING A CHANCE FOR SOME
SHOWERS INTO THE FOOTHILLS AND BASINS EAST OF THE DIVIDE...KEPT
POPS QUIET FOR NOW BUT WOULD NOT BE SURPRISED IF A SHOWER OR TWO
MADE IT INTO THESE AREAS. THIS WILL NOT BE A SIGNIFICANT RAIN OR
SNOW PRODUCER BUT IT WILL COOL THINGS OFF A BIT...INCREASE CLOUD
COVER AND WIND SPEEDS ACROSS THE REGION TUESDAY AND TUESDAY
NIGHT...ESPECIALLY ALONG THE CODY FOOTHILLS AND THE UPPER WIND
RIVER BASIN OVERNIGHT AS THE SUBSIDENT BACK SIDE OF THE WAVE
PASSES OVERHEAD. THIS SHOULD HELP FORCE DOWN SOME STRONGER WIND
GUSTS INTO THE FOOTHILLS. CROSS SECTIONS ALONG THE ABSAROKAS SHOW
THE POTENTIAL FOR A BREAKING MOUNTAIN WAVE ALONG THE WESTERN CODY
FOOTHILLS OVERNIGHT...THIS WAVE COULD PRODUCE WIND GUSTS OVER 60
MPH AROUND CLARK AND WEST OF CODY. THE WAVE LIFTS OUT ON
WEDNESDAY...LEAVING BEHIND SOME COOLER BUT AVERAGE TEMPERATURES
FOR THIS TIME OF YEAR...AND SOME BREEZY WESTERLIES ACROSS THE
SOUTH.

.LONG TERM...THURSDAY THROUGH MONDAY

SYNOPSIS...UNSEASONABLY MILD AND DRY CONDITIONS WILL PREVAIL
THURSDAY THROUGH SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE
ON SATURDAY.  A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT
WILL MOVE ACROSS THE AREA SUNDAY AND MONDAY BRINGING A CHANCE OF
RAIN AND SNOW SHOWERS ALONG WITH COLDER TEMPERATURES.

DISCUSSION...UPPER HIGH STRENGTHENS OVER THE SOUTHERN ROCKIES
THURSDAY AND FRIDAY WITH BUILDING HEIGHTS ACROSS WYOMING WHILE
PACIFIC TROUGH SHARPENS NEAR 130W ON FRIDAY. UPPER TROUGH IS
FORECAST TO MAKE LANDFALL ALONG THE WEST COAST LATE SATURDAY WITH
LEAD SHORTWAVE EJECTING NE ACROSS THE INTERMOUNTAIN WEST INTO
SOUTHERN ALBERTA. THIS WILL BRING INCREASING SW FLOW ACROSS THE
AREA SATURDAY WITH LEE SIDE LOW DEVELOPMENT EXPECTED OVER CENTRAL
MONTANA PUTTING CENTRAL WYOMING IN WARM SECTOR. RECORD HIGH
TERRITORY FOR MANY LOCATIONS IS UPPER 60S TO LOWER 70S (73 AT
LND...72 AT CPR) SO THESE RECORDS WILL LIKELY BE IN JEOPARDY...AND
WITH GUSTY SOUTHWEST WIND...FIRE DANGER WILL BE ELEVATED.

GFS REMAINS MORE PROGRESSIVE THAN THE ECMWF BRINGING UPPER TROUGH
AND ASSOCIATED FRONT ACROSS THE AREA SUNDAY...AND 20/00Z ECMWF
DETERMINISTIC IS OUT AHEAD OF THE EC ENSEMBLE MEAN.  SO ALTHOUGH
AGREEMENT BETWEEN THE GFS AND ECMWF DETERMINISTIC RUNS IS MUCH
BETTER THIS MORNING...MEDIUM-RANGE MODELS HAVE YET TO SHOW ANY
DEGREE OF RUN-TO-RUN CONSISTENCY TO GAIN MUCH CONFIDENCE IN
TIMING OF COLD FRONT AND ONSET OF PRECIPITATION...WITH AN OVERALL
PREFERENCE TOWARD SLOWER PROGRESSION PER THE EC ENSEMBLE MEAN.
THIS RESULTS IN BRINGING CHANCES OF PRECIPITATION INTO THE WEST ON
SUNDAY AND SPREADING ACROSS THE AREA SUNDAY NIGHT INTO MONDAY.
TEMPERATURES ON MONDAY ARE EXPECTED TO BE SOME 20-25F COOLER THAN
NEAR RECORD HIGH TEMPERATURES ON SATURDAY...OR 5-10F BELOW NORMAL.

.AVIATION.../18Z ISSUANCE/

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS...INCLUDING
THE AIRPORTS THROUGH 18Z TUESDAY. AN APPROACHING PACIFIC LOW PRESSURE
TROUGH WILL BRING INCREASED CLOUD COVER AND SHOWER ACTIVITY OVER
THE MOUNTAINS ALONG AND EAST OF THE CONTINENTAL DIVIDE AFTER 10Z
WITH AREAS OF MVFR TO IFR CEILINGS...AND VISIBILITIES REDUCED IN
SHOWERS INCREASING AND OBSCURING THE HIGHER MOUNTAINS. STRONG
WEST TO SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE SHOWERS AND
CLOUDS BECOMING 25-30KTS WITH GUSTS TO 40KTS ALONG AND NEAR THE
EAST SLOPES OF THE MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM
KRKS TO KCPR.

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

VFR CONDITIONS WILL PREVAIL IN THE LOWER ELEVATIONS...INCLUDING
THE AIRPORTS THROUGH 10Z TUESDAY. AN APPROACHING PACIFIC LOW
PRESSURE TROUGH WILL BRING INCREASED CLOUD COVER AND SHOWER
ACTIVITY OVER THE MOUNTAINS AND FAR WESTERN VALLEYS AFTER 07Z
WITH AREAS OF MVFR TO IFR CEILINGS...AND VISIBILITIES REDUCED IN
SHOWERS INCREASING AND OBSCURING THE HIGHER MOUNTAINS. BRIEF MVFR
CONDITIONS MAY OCCUR AT KJAC...KAFO...KEMM...KBPI AND KPNA AFTER
10Z. STRONG WEST TO SOUTHWEST WINDS WILL ALSO MOVE IN WITH THE
SHOWERS AND CLOUDS BECOMING 20-25KTS WITH GUSTS TO 35KTS OVER THE
MOUNTAINS AND THROUGH THE WIND CORRIDOR FROM KEVW TO KRKS.

.FIRE WEATHER...

SEASONABLY WARM TEMPERATURES AND LOW WIND SPEEDS CONTINUE AGAIN TODAY.
WHILE RELATIVE HUMIDITY VALUES MAY DIP INTO THE LOWER 20S OR EVEN
UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN ON THE LOW
SIDE...HELPING TO AVOID ENHANCED FIRE DANGER. HOWEVER...WIND SPEEDS
WILL INCREASE ON TUESDAY AHEAD OF THE NEXT STORM. CHANCES OF WETTING
RAIN WILL BE FAIRLY HIGH ACROSS THE HIGHER ELEVATIONS...THE WEST AND
ACROSS RAWLINS DISPATCH...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...C.BAKER
FIRE WEATHER...ALLEN








000
FXUS65 KRIW 200940
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
340 AM MDT MON OCT 20 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

ONE MORE WARM DAY UNDERNEATH THE RIDGE TODAY AND TONIGHT
...TEMPERATURES WILL REMAIN 10 TO 15 DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR. A COLD FRONT WILL APPROACH THE WEST EARLY TUESDAY
MORNING...SWEEPING EAST THROUGH THE DAY. THE APPROACHING TROUGH
AND ASSOCIATED FRONT WILL CREATE A WINDY DAY FOR MUCH OF THE AREA
ON TUESDAY OTHERWISE THERE WILL BE A CHANCE FOR SOME RAIN...AND
SNOW ABOVE 6KFT RISING TO ABOUT 8.5KFT IN THE AFTERNOON...MAINLY
IN THE NORTHWESTERN MOUNTAINS AND YELLOWSTONE. SOME RAIN WILL BE
SPILLING ACROSS THE SOUTH AND INTO SOME AREAS EAST OF THE DIVIDE.
IT IS STARTING TO LOOK A BIT MORE UNSTABLE FOR TUESDAY AFTERNOON
THAN PREVIOUS RUNS...SO A SLIGHT CHANCE FOR THUNDER WAS INCLUDED
WITH THIS PACKAGE FOR THE 18Z TUE-00Z WED TIMEFRAME. THIS
INSTABILITY COULD HELP OVERCOME SOME OF THE DOWNSLOPING AFFECTS OF
THE SWIFT WEST AND SOUTHWEST FLOW...BRINGING A CHANCE FOR SOME
SHOWERS INTO THE FOOTHILLS AND BASINS EAST OF THE DIVIDE...KEPT
POPS QUIET FOR NOW BUT WOULD NOT BE SURPRISED IF A SHOWER OR TWO
MADE IT INTO THESE AREAS. THIS WILL NOT BE A SIGNIFICANT RAIN OR
SNOW PRODUCER BUT IT WILL COOL THINGS OFF A BIT...INCREASE CLOUD
COVER AND WIND SPEEDS ACROSS THE REGION TUESDAY AND TUESDAY
NIGHT...ESPECIALLY ALONG THE CODY FOOTHILLS AND THE UPPER WIND
RIVER BASIN OVERNIGHT AS THE SUBSIDENT BACK SIDE OF THE WAVE
PASSES OVERHEAD. THIS SHOULD HELP FORCE DOWN SOME STRONGER WIND
GUSTS INTO THE FOOTHILLS. CROSS SECTIONS ALONG THE ABSAROKAS SHOW
THE POTENTIAL FOR A BREAKING MOUNTAIN WAVE ALONG THE WESTERN CODY
FOOTHILLS OVERNIGHT...THIS WAVE COULD PRODUCE WIND GUSTS OVER 60
MPH AROUND CLARK AND WEST OF CODY. THE WAVE LIFTS OUT ON
WEDNESDAY...LEAVING BEHIND SOME COOLER BUT AVERAGE TEMPERATURES
FOR THIS TIME OF YEAR...AND SOME BREEZY WESTERLIES ACROSS THE
SOUTH.

.LONG TERM...THURSDAY THROUGH MONDAY
SYNOPSIS...UNSEASONABLY MILD AND DRY CONDITIONS WILL PREVAIL
THURSDAY THROUGH SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE
ON SATURDAY.  A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT
WILL MOVE ACROSS THE AREA SUNDAY AND MONDAY BRINGING A CHANCE OF
RAIN AND SNOW SHOWERS ALONG WITH COLDER TEMPERATURES.

DISCUSSION...UPPER HIGH STRENGTHENS OVER THE SOUTHERN ROCKIES
THURSDAY AND FRIDAY WITH BUILDING HEIGHTS ACROSS WYOMING WHILE
PACIFIC TROUGH SHARPENS NEAR 130W ON FRIDAY. UPPER TROUGH IS
FORECAST TO MAKE LANDFALL ALONG THE WEST COAST LATE SATURDAY WITH
LEAD SHORTWAVE EJECTING NE ACROSS THE INTERMOUNTAIN WEST INTO
SOUTHERN ALBERTA. THIS WILL BRING INCREASING SW FLOW ACROSS THE
AREA SATURDAY WITH LEE SIDE LOW DEVELOPMENT EXPECTED OVER CENTRAL
MONTANA PUTTING CENTRAL WYOMING IN WARM SECTOR. RECORD HIGH
TERRITORY FOR MANY LOCATIONS IS UPPER 60S TO LOWER 70S (73 AT
LND...72 AT CPR) SO THESE RECORDS WILL LIKELY BE IN JEOPARDY...AND
WITH GUSTY SOUTHWEST WIND...FIRE DANGER WILL BE ELEVATED.

GFS REMAINS MORE PROGRESSIVE THAN THE ECMWF BRINGING UPPER TROUGH
AND ASSOCIATED FRONT ACROSS THE AREA SUNDAY...AND 20/00Z ECMWF
DETERMINISTIC IS OUT AHEAD OF THE EC ENSEMBLE MEAN.  SO ALTHOUGH
AGREEMENT BETWEEN THE GFS AND ECMWF DETERMINISTIC RUNS IS MUCH
BETTER THIS MORNING...MEDIUM-RANGE MODELS HAVE YET TO SHOW ANY
DEGREE OF RUN-TO-RUN CONSISTENCY TO GAIN MUCH CONFIDENCE IN
TIMING OF COLD FRONT AND ONSET OF PRECIPITATION...WITH AN OVERALL
PREFERENCE TOWARD SLOWER PROGRESSION PER THE EC ENSEMBLE MEAN.
THIS RESULTS IN BRINGING CHANCES OF PRECIPITATION INTO THE WEST ON
SUNDAY AND SPREADING ACROSS THE AREA SUNDAY NIGHT INTO MONDAY.
TEMPERATURES ON MONDAY ARE EXPECTED TO BE SOME 20-25F COOLER THAN
NEAR RECORD HIGH TEMPERATURES ON SATURDAY...OR 5-10F BELOW NORMAL.

&&

.AVIATION.../12Z ISSUANCE/

ALL TERMINALS WILL BE VFR THROUGH THE FORECAST PERIOD. SOUTHWEST
SURFACE WIND OF 10-15KTS EXPECTED UNTIL ABOUT 23Z TODAY AT KCPR WITH
LEE TROUGH OVER THE EASTERN WYOMING PLAINS. OTHER TERMINALS WILL BE
LESS THAN 10KTS...ALTHOUGH SOUTHEAST UPSLOPE WIND WILL BE NEAR THAT
MARK AT KCOD THIS AFTERNOON. MID/HIGH LEVEL MOISTURE WILL BEGIN TO
CIRCULATE NORTH INTO THE FAR WEST AND SOUTHWEST AFTER 06Z/TUE.

&&

.FIRE WEATHER...

SEASONABLY WARM TEMPERATURES AND LOW WIND SPEEDS CONTINUE AGAIN TODAY.
WHILE RELATIVE HUMIDITY VALUES MAY DIP INTO THE LOWER 20S OR EVEN
UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN ON THE LOW
SIDE...HELPING TO AVOID ENHANCED FIRE DANGER. HOWEVER...WIND SPEEDS
WILL INCREASE ON TUESDAY AHEAD OF THE NEXT STORM. CHANCES OF WETTING
RAIN WILL BE FAIRLY HIGH ACROSS THE HIGHER ELEVATIONS...THE WEST AND
ACROSS RAWLINS DISPATCH...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ
FIRE WEATHER...ALLEN









000
FXUS65 KRIW 200940
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
340 AM MDT MON OCT 20 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

ONE MORE WARM DAY UNDERNEATH THE RIDGE TODAY AND TONIGHT
...TEMPERATURES WILL REMAIN 10 TO 15 DEGREES ABOVE NORMAL FOR THIS
TIME OF YEAR. A COLD FRONT WILL APPROACH THE WEST EARLY TUESDAY
MORNING...SWEEPING EAST THROUGH THE DAY. THE APPROACHING TROUGH
AND ASSOCIATED FRONT WILL CREATE A WINDY DAY FOR MUCH OF THE AREA
ON TUESDAY OTHERWISE THERE WILL BE A CHANCE FOR SOME RAIN...AND
SNOW ABOVE 6KFT RISING TO ABOUT 8.5KFT IN THE AFTERNOON...MAINLY
IN THE NORTHWESTERN MOUNTAINS AND YELLOWSTONE. SOME RAIN WILL BE
SPILLING ACROSS THE SOUTH AND INTO SOME AREAS EAST OF THE DIVIDE.
IT IS STARTING TO LOOK A BIT MORE UNSTABLE FOR TUESDAY AFTERNOON
THAN PREVIOUS RUNS...SO A SLIGHT CHANCE FOR THUNDER WAS INCLUDED
WITH THIS PACKAGE FOR THE 18Z TUE-00Z WED TIMEFRAME. THIS
INSTABILITY COULD HELP OVERCOME SOME OF THE DOWNSLOPING AFFECTS OF
THE SWIFT WEST AND SOUTHWEST FLOW...BRINGING A CHANCE FOR SOME
SHOWERS INTO THE FOOTHILLS AND BASINS EAST OF THE DIVIDE...KEPT
POPS QUIET FOR NOW BUT WOULD NOT BE SURPRISED IF A SHOWER OR TWO
MADE IT INTO THESE AREAS. THIS WILL NOT BE A SIGNIFICANT RAIN OR
SNOW PRODUCER BUT IT WILL COOL THINGS OFF A BIT...INCREASE CLOUD
COVER AND WIND SPEEDS ACROSS THE REGION TUESDAY AND TUESDAY
NIGHT...ESPECIALLY ALONG THE CODY FOOTHILLS AND THE UPPER WIND
RIVER BASIN OVERNIGHT AS THE SUBSIDENT BACK SIDE OF THE WAVE
PASSES OVERHEAD. THIS SHOULD HELP FORCE DOWN SOME STRONGER WIND
GUSTS INTO THE FOOTHILLS. CROSS SECTIONS ALONG THE ABSAROKAS SHOW
THE POTENTIAL FOR A BREAKING MOUNTAIN WAVE ALONG THE WESTERN CODY
FOOTHILLS OVERNIGHT...THIS WAVE COULD PRODUCE WIND GUSTS OVER 60
MPH AROUND CLARK AND WEST OF CODY. THE WAVE LIFTS OUT ON
WEDNESDAY...LEAVING BEHIND SOME COOLER BUT AVERAGE TEMPERATURES
FOR THIS TIME OF YEAR...AND SOME BREEZY WESTERLIES ACROSS THE
SOUTH.

.LONG TERM...THURSDAY THROUGH MONDAY
SYNOPSIS...UNSEASONABLY MILD AND DRY CONDITIONS WILL PREVAIL
THURSDAY THROUGH SATURDAY WITH RECORD OR NEAR RECORD HIGHS POSSIBLE
ON SATURDAY.  A TROUGH OF LOW PRESSURE AND ASSOCIATED COLD FRONT
WILL MOVE ACROSS THE AREA SUNDAY AND MONDAY BRINGING A CHANCE OF
RAIN AND SNOW SHOWERS ALONG WITH COLDER TEMPERATURES.

DISCUSSION...UPPER HIGH STRENGTHENS OVER THE SOUTHERN ROCKIES
THURSDAY AND FRIDAY WITH BUILDING HEIGHTS ACROSS WYOMING WHILE
PACIFIC TROUGH SHARPENS NEAR 130W ON FRIDAY. UPPER TROUGH IS
FORECAST TO MAKE LANDFALL ALONG THE WEST COAST LATE SATURDAY WITH
LEAD SHORTWAVE EJECTING NE ACROSS THE INTERMOUNTAIN WEST INTO
SOUTHERN ALBERTA. THIS WILL BRING INCREASING SW FLOW ACROSS THE
AREA SATURDAY WITH LEE SIDE LOW DEVELOPMENT EXPECTED OVER CENTRAL
MONTANA PUTTING CENTRAL WYOMING IN WARM SECTOR. RECORD HIGH
TERRITORY FOR MANY LOCATIONS IS UPPER 60S TO LOWER 70S (73 AT
LND...72 AT CPR) SO THESE RECORDS WILL LIKELY BE IN JEOPARDY...AND
WITH GUSTY SOUTHWEST WIND...FIRE DANGER WILL BE ELEVATED.

GFS REMAINS MORE PROGRESSIVE THAN THE ECMWF BRINGING UPPER TROUGH
AND ASSOCIATED FRONT ACROSS THE AREA SUNDAY...AND 20/00Z ECMWF
DETERMINISTIC IS OUT AHEAD OF THE EC ENSEMBLE MEAN.  SO ALTHOUGH
AGREEMENT BETWEEN THE GFS AND ECMWF DETERMINISTIC RUNS IS MUCH
BETTER THIS MORNING...MEDIUM-RANGE MODELS HAVE YET TO SHOW ANY
DEGREE OF RUN-TO-RUN CONSISTENCY TO GAIN MUCH CONFIDENCE IN
TIMING OF COLD FRONT AND ONSET OF PRECIPITATION...WITH AN OVERALL
PREFERENCE TOWARD SLOWER PROGRESSION PER THE EC ENSEMBLE MEAN.
THIS RESULTS IN BRINGING CHANCES OF PRECIPITATION INTO THE WEST ON
SUNDAY AND SPREADING ACROSS THE AREA SUNDAY NIGHT INTO MONDAY.
TEMPERATURES ON MONDAY ARE EXPECTED TO BE SOME 20-25F COOLER THAN
NEAR RECORD HIGH TEMPERATURES ON SATURDAY...OR 5-10F BELOW NORMAL.

&&

.AVIATION.../12Z ISSUANCE/

ALL TERMINALS WILL BE VFR THROUGH THE FORECAST PERIOD. SOUTHWEST
SURFACE WIND OF 10-15KTS EXPECTED UNTIL ABOUT 23Z TODAY AT KCPR WITH
LEE TROUGH OVER THE EASTERN WYOMING PLAINS. OTHER TERMINALS WILL BE
LESS THAN 10KTS...ALTHOUGH SOUTHEAST UPSLOPE WIND WILL BE NEAR THAT
MARK AT KCOD THIS AFTERNOON. MID/HIGH LEVEL MOISTURE WILL BEGIN TO
CIRCULATE NORTH INTO THE FAR WEST AND SOUTHWEST AFTER 06Z/TUE.

&&

.FIRE WEATHER...

SEASONABLY WARM TEMPERATURES AND LOW WIND SPEEDS CONTINUE AGAIN TODAY.
WHILE RELATIVE HUMIDITY VALUES MAY DIP INTO THE LOWER 20S OR EVEN
UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN ON THE LOW
SIDE...HELPING TO AVOID ENHANCED FIRE DANGER. HOWEVER...WIND SPEEDS
WILL INCREASE ON TUESDAY AHEAD OF THE NEXT STORM. CHANCES OF WETTING
RAIN WILL BE FAIRLY HIGH ACROSS THE HIGHER ELEVATIONS...THE WEST AND
ACROSS RAWLINS DISPATCH...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...ALLEN
LONG TERM...AEM
AVIATION...CNJ
FIRE WEATHER...ALLEN










000
FXUS65 KRIW 200521
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1121 PM MDT SUN OCT 19 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

HIGH PRESSURE SURFACE AND ALOFT WILL PRODUCE A DRY STABLE AIR MASS
OVER WESTERN AND CENTRAL WYOMING TONIGHT AND MONDAY WITH MILD
TEMPERATURES AND LIGHT WIND. MODELS IN VERY GOOD AGREEMENT AT THIS
POINT.

.LONG TERM...MONDAY NIGHT THROUGH SUNDAY

THE BEGINNING OF THE FCST PERIOD HAS THE FA ON THE BACKSIDE OF THE
EXITING UPR RIDGE OR ON THE LEADING EDGE OF APPROACHING TROF...TAKE
YOUR PICK. FLOW THRU THE UPR PATTERN CONTINUES TO TAKE
DISTURBANCES...WHEN THEY HAPPEN...QUICKLY THRU THE FLOW...NOT
ALLOWING FOR MUCH IN THE WAY OF REGIONAL/LOCAL DEVELOPMENT.

SFC LEE SIDE TROFFING E OF BIGHORNS SHOULD JUST BE ONGOING AHEAD OF
THE TROF W/ WEAK CYCLO/FRONTO -GENESIS PROCEEDING THRU THE DAY
TUESDAY...AHEAD OF A MOBILE TROF ALONG/AHEAD OF JET...SOMEWHERE OVER
AND ALONG THE SFC TROF. ATTM...MOISTURE LOOKS TO COME TO THE FA IN
TWO WAYS...BOTH RATHER LIMITED HOWEVER. ONE...FROM THE EPAC RIDING
IN WITH THE SW TROF...THE OTHER FROM THE S/SW AROUND BUILDING HIGH
PRESSURE OVR THE SCNTRL STATES. TRAJECTORY ISSUES WITH THE SRN
MOISTURE BRANCH WILL LARGELY DICTATE JUST HOW MUCH MOISTURE HAS THE
POSSIBILITY OF GETTING INTO THE FA TO BEGIN WITH...AND THEN HOW MUCH
GETS WRUNG OUT OVR THE CNTRL ROCKIES BEFORE ENTERING THE FA WHEN IT
DOES. STILL...CHC TO LOW END LIKELY IN THE MOUNTAINS LOOKS
GOOD...PARTICULARLY TUE NIGHT THRU WED MORNING. AS THIS SYSTEM
CONTINUES TO LOOK QUITE PROGRESSIVE AND POSSIBLY MOISTURE
CHALLENGED...WILL KEEP QPF VALUES FOR ANY 6 HR PERIOD AOB .30IN IN
THE MOUNTAINS...WHICH IS A THIRD TO A HALF OF WHAT SOME MDLS ARE
SPITTING OUT IN THIS SPLIT SITUATION. THIS WILL KEEP 24 HR SNOWFALL
POTENTIAL EVEN OVER THE HIGHEST PEAKS AOB 6IN AT BEST. WILL WATCH
FOR REASONS TO INCREASE/DECREASE THESE LIQUID/FROZEN TOTALS OVER THE
NEXT DAY OR TWO. LOW ELEVATIONS DO NOT CURRENTLY LOOK TO BE IMPACTED
MUCH...WITH SOME LIGHT RAIN PERHAPS MIXING WITH SNOW AT BEST FOR A
BRIEF PERIOD EARLY WED.

BEYOND WED...AS SW TROF QUICKLY EXITS...FLAT MODEST RIDGING RETURNS
TO THE AREA BY WED EVE. FROM THIS POINT ON MDLS BEGIN TO DIVERGE AND
CONTINUE TO INCREASE IN DIFFERENCES THROUGHOUT THE REST OF THE FCST.
WHILE SOME MINOR AMPLITUDE DIFFERENCES ARISE ALONG THE WAY...MAIN
DIFFERENCES SHOWING IN THE ENSEMBLE MEAN OUTPUT OF THE RESPECTIVE
MDLS PING ON HOW TO HANDLE (OR NOT TO HANDLE) AN EJECTING NORTHERN
JET AND THE EFFECT ON THE TROF THAT IS ASSOCIATED WITH IT...LEADING
TO SEVERE TIMING DIFFERENCES BY THE END OF THE FCST PERIOD.
LUCKILY...ANY MOISTURE SOURCE INTO THE REGION WILL BE SEVERELY
LACKING DURING MOST OF THIS TIMEFRAME...SO MOST PRECIP CHCS WILL BE
SUPPRESSED BELOW ISOLATED THRU THE FCST...WITH ONLY LOW END ISOLATED
CHCS ARISING BY SUNDAY...DUE MOSTLY TO THE INFLUENCE OF THE GFS AND
ITS FASTER SOLUTION. NOTHING SPECTACULAR EVEN IF SOMETHING DOES
HAPPEN IN THE GENERALLY VERY PROGRESSIVE AND DRY ATMOSPHERE.

&&

.AVIATION.../06Z ISSUANCE/

CONDITIONS WILL REMAIN VFR THROUGH 06Z/TUE. WINDS WILL BE LESS THAN
10KTS AT ALL TERMINALS EXCEPT KCPR. TROUGH ON THE EASTERN WYOMING
PLAINS WILL GENERATE 10-15KT SOUTHWEST SURFACE WIND AT KCPR FROM
AROUND 12Z-23Z TODAY.

&&

.FIRE WEATHER...

HIGH PRESSURE SURFACE AND ALOFT WILL DOMINATE THE WEATHER THROUGH
MONDAY NIGHT WITH A DRY STABLE AIR MASS AND SEASONABLY WARM
TEMPERATURES AND LOW WIND SPEEDS. RELATIVE HUMIDITY WILL DIP INTO THE
LOWER 20S AND UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN LOW
HELPING TO AVOID ENHANCED FIRE DANGER.  WIND SPEEDS WILL INCREASE
ON TUESDAY AHEAD OF AN APPROACHING PACIFIC LOW PRESSURE TROUGH ON
TUESDAY. WINDS AND MOISTURE WILL INCREASE TUESDAY NIGHT AND
WEDNESDAY WITH CHANCES OF WETTING RAIN INCREASING ACROSS THE
HIGHER ELEVATIONS OF THE WEST AND ACROSS RAWLINS DISPATCH
AREA...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRAUN
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER










000
FXUS65 KRIW 200521
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1121 PM MDT SUN OCT 19 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

HIGH PRESSURE SURFACE AND ALOFT WILL PRODUCE A DRY STABLE AIR MASS
OVER WESTERN AND CENTRAL WYOMING TONIGHT AND MONDAY WITH MILD
TEMPERATURES AND LIGHT WIND. MODELS IN VERY GOOD AGREEMENT AT THIS
POINT.

.LONG TERM...MONDAY NIGHT THROUGH SUNDAY

THE BEGINNING OF THE FCST PERIOD HAS THE FA ON THE BACKSIDE OF THE
EXITING UPR RIDGE OR ON THE LEADING EDGE OF APPROACHING TROF...TAKE
YOUR PICK. FLOW THRU THE UPR PATTERN CONTINUES TO TAKE
DISTURBANCES...WHEN THEY HAPPEN...QUICKLY THRU THE FLOW...NOT
ALLOWING FOR MUCH IN THE WAY OF REGIONAL/LOCAL DEVELOPMENT.

SFC LEE SIDE TROFFING E OF BIGHORNS SHOULD JUST BE ONGOING AHEAD OF
THE TROF W/ WEAK CYCLO/FRONTO -GENESIS PROCEEDING THRU THE DAY
TUESDAY...AHEAD OF A MOBILE TROF ALONG/AHEAD OF JET...SOMEWHERE OVER
AND ALONG THE SFC TROF. ATTM...MOISTURE LOOKS TO COME TO THE FA IN
TWO WAYS...BOTH RATHER LIMITED HOWEVER. ONE...FROM THE EPAC RIDING
IN WITH THE SW TROF...THE OTHER FROM THE S/SW AROUND BUILDING HIGH
PRESSURE OVR THE SCNTRL STATES. TRAJECTORY ISSUES WITH THE SRN
MOISTURE BRANCH WILL LARGELY DICTATE JUST HOW MUCH MOISTURE HAS THE
POSSIBILITY OF GETTING INTO THE FA TO BEGIN WITH...AND THEN HOW MUCH
GETS WRUNG OUT OVR THE CNTRL ROCKIES BEFORE ENTERING THE FA WHEN IT
DOES. STILL...CHC TO LOW END LIKELY IN THE MOUNTAINS LOOKS
GOOD...PARTICULARLY TUE NIGHT THRU WED MORNING. AS THIS SYSTEM
CONTINUES TO LOOK QUITE PROGRESSIVE AND POSSIBLY MOISTURE
CHALLENGED...WILL KEEP QPF VALUES FOR ANY 6 HR PERIOD AOB .30IN IN
THE MOUNTAINS...WHICH IS A THIRD TO A HALF OF WHAT SOME MDLS ARE
SPITTING OUT IN THIS SPLIT SITUATION. THIS WILL KEEP 24 HR SNOWFALL
POTENTIAL EVEN OVER THE HIGHEST PEAKS AOB 6IN AT BEST. WILL WATCH
FOR REASONS TO INCREASE/DECREASE THESE LIQUID/FROZEN TOTALS OVER THE
NEXT DAY OR TWO. LOW ELEVATIONS DO NOT CURRENTLY LOOK TO BE IMPACTED
MUCH...WITH SOME LIGHT RAIN PERHAPS MIXING WITH SNOW AT BEST FOR A
BRIEF PERIOD EARLY WED.

BEYOND WED...AS SW TROF QUICKLY EXITS...FLAT MODEST RIDGING RETURNS
TO THE AREA BY WED EVE. FROM THIS POINT ON MDLS BEGIN TO DIVERGE AND
CONTINUE TO INCREASE IN DIFFERENCES THROUGHOUT THE REST OF THE FCST.
WHILE SOME MINOR AMPLITUDE DIFFERENCES ARISE ALONG THE WAY...MAIN
DIFFERENCES SHOWING IN THE ENSEMBLE MEAN OUTPUT OF THE RESPECTIVE
MDLS PING ON HOW TO HANDLE (OR NOT TO HANDLE) AN EJECTING NORTHERN
JET AND THE EFFECT ON THE TROF THAT IS ASSOCIATED WITH IT...LEADING
TO SEVERE TIMING DIFFERENCES BY THE END OF THE FCST PERIOD.
LUCKILY...ANY MOISTURE SOURCE INTO THE REGION WILL BE SEVERELY
LACKING DURING MOST OF THIS TIMEFRAME...SO MOST PRECIP CHCS WILL BE
SUPPRESSED BELOW ISOLATED THRU THE FCST...WITH ONLY LOW END ISOLATED
CHCS ARISING BY SUNDAY...DUE MOSTLY TO THE INFLUENCE OF THE GFS AND
ITS FASTER SOLUTION. NOTHING SPECTACULAR EVEN IF SOMETHING DOES
HAPPEN IN THE GENERALLY VERY PROGRESSIVE AND DRY ATMOSPHERE.

&&

.AVIATION.../06Z ISSUANCE/

CONDITIONS WILL REMAIN VFR THROUGH 06Z/TUE. WINDS WILL BE LESS THAN
10KTS AT ALL TERMINALS EXCEPT KCPR. TROUGH ON THE EASTERN WYOMING
PLAINS WILL GENERATE 10-15KT SOUTHWEST SURFACE WIND AT KCPR FROM
AROUND 12Z-23Z TODAY.

&&

.FIRE WEATHER...

HIGH PRESSURE SURFACE AND ALOFT WILL DOMINATE THE WEATHER THROUGH
MONDAY NIGHT WITH A DRY STABLE AIR MASS AND SEASONABLY WARM
TEMPERATURES AND LOW WIND SPEEDS. RELATIVE HUMIDITY WILL DIP INTO THE
LOWER 20S AND UPPER TEENS AT TIMES...WINDS SPEEDS WILL REMAIN LOW
HELPING TO AVOID ENHANCED FIRE DANGER.  WIND SPEEDS WILL INCREASE
ON TUESDAY AHEAD OF AN APPROACHING PACIFIC LOW PRESSURE TROUGH ON
TUESDAY. WINDS AND MOISTURE WILL INCREASE TUESDAY NIGHT AND
WEDNESDAY WITH CHANCES OF WETTING RAIN INCREASING ACROSS THE
HIGHER ELEVATIONS OF THE WEST AND ACROSS RAWLINS DISPATCH
AREA...WITH A LOW CHANCE EAST OF THE DIVIDE.

&&

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

$$

SHORT TERM...C.BAKER
LONG TERM...BRAUN
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER











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