Alert archive / Wyoming / Winter Storm Warnings in 2011

Winter Storm Warning 3, NWS Riverton, WY

January 18, 2011Lincoln County, Teton County, Wyoming

NWS Riverton, WY issued this winter storm warning at Jan 18, 2011, 10:48 PM MST for Lincoln County, Teton County, Wyoming. It was in force for 10 hr. 23 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jan 18, 2011, 10:48 PM MST (05:48 UTC)
Expired
Jan 19, 2011, 8:38 AM MST
In force
10 hr
Issued by
NWS Riverton, WY

Counties Lincoln County, WY, Teton County, WY

The radar

The Pocatello radar (KSFX), 167 km from the middle of the area, began a volume at 05:49 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jan 19, 5:32 AM MSTHEAVY SNOW 101 Se Thayne, WY
Jan 19, 5:32 AM MSTHEAVY SNOW 13Wilson, WY
Jan 19, 5:33 AM MSTHEAVY SNOW 68 Nne Moran Junction, WYBASE CAMP SNOTEL
Jan 19, 5:34 AM MSTSNOW 520 Ne Bondurant, WYGROS VENTRE SUMMIT SNOTEL
Jan 19, 5:34 AM MSTHEAVY SNOW 66 Ene Alta, WYGRAND TARGHEE SNOTEL
Jan 19, 5:34 AM MSTHEAVY SNOW 78 W South Entrance, WYGRASSY LAKE SNOTEL
Jan 19, 5:34 AM MSTHEAVY SNOW 810 N Bondurant, WYGRANITE CREEK SNOTEL
Jan 19, 5:35 AM MSTSNOW 4South Entrance, WYSNAKE RIVER STN SNOTEL
Jan 19, 5:35 AM MSTSNOW 526 N Kemmerer, WYHAMS FORK SNOTEL
Jan 19, 5:35 AM MSTHEAVY SNOW 626 Nw Dubois, WYTOGWOTEE PASS
Jan 19, 5:35 AM MSTHEAVY SNOW 118 Wnw Jackson, WYPHILLIPS BENCH SNOTEL
Jan 19, 5:35 AM MSTHEAVY SNOW 128 Se Afton, WYCOTTONWOOD CREEK SNOTEL
Jan 19, 5:36 AM MSTHEAVY SNOW 615 Nne Cokeville, WYKELLEY RANGER STATION SNOTEL
Jan 19, 5:36 AM MSTHEAVY SNOW 715 S Afton, WYSALT RIVER SUMMIT SNOTEL
Jan 19, 5:36 AM MSTHEAVY SNOW 719 Se Afton, WYSPRING CREEK DIVIDE SNOTEL
Jan 19, 5:36 AM MSTHEAVY SNOW 836 N Kemmerer, WYINDIAN CREEK SNOTEL
Jan 19, 5:37 AM MSTHEAVY SNOW 118 Ne Afton, WYWILLOW CREEK SNOTEL
Jan 19, 5:38 AM MSTHEAVY SNOW 129.9 Nnw Jackson, WYJACKSON HOLE-RAYMER
Jan 19, 5:39 AM MSTHEAVY SNOW 81 S Jackson, WYSNOW KING SKI AREA
Jan 19, 5:39 AM MSTHEAVY SNOW 1119 Sw Bondurant, WYBLIND BULL SUMMIT SNOTEL
Jan 19, 5:39 AM MSTHEAVY SNOW 1417.2 E Thayne, WYBLIND BULL SUMMIT
Jan 19, 5:40 AM MSTHEAVY SNOW 814.3 E Thayne, WYBOX Y RANCH
Jan 19, 5:40 AM MSTHEAVY SNOW 88.6 Nnw Jackson, WYJACKSON HOLE-BASE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 5.8 hours before the alert went out and 181 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Riverton, WY at 00:00Z on 2011-01-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 00:00Z on 2011-01-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2980 m above ground
0-6 km bulk shear
81 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
189 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

575 
WWUS45 KRIW 190548
WSWRIW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
1048 PM MST TUE JAN 18 2011

...STORM SYSTEM TO IMPACT THE WEST THROUGH WEDNESDAY MORNING...

.A STORM SYSTEM WILL MOVE SOUTHEAST INTO SOUTHWEST WYOMING BY
MORNING. SNOW WILL OCCUR...MODERATE TO HEAVY AT TIMES THROUGH 5 AM
...THEN TAPERING OFF TO LIGHT SNOW.

WYZ013-191400-
/O.UPG.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
/O.NEW.KRIW.WS.W.0003.110119T0548Z-110119T1800Z/
JACKSON HOLE-
INCLUDING THE CITY OF...JACKSON
1048 PM MST TUE JAN 18 2011

...WINTER STORM WARNING IN EFFECT UNTIL 11 AM MST WEDNESDAY...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A WINTER
STORM WARNING FOR HEAVY SNOW WHICH IS IN EFFECT UNTIL 11 AM MST
WEDNESDAY. THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT.

* SUMMARY AND TIMING...SNOW WILL OCCUR OVERNIGHT. THE HEAVIEST
  PERIOD OF SNOWFALL WILL OCCUR THROUGH 4 AM...THEN TAPER OFF TO
  LIGHT SNOW THROUGH WEDNESDAY MORNING. SNOWFALL RATES OF 1 INCH
  PER HOUR IS LIKELY IN HEAVY SNOW.

* SNOW ACCUMULATIONS...4 TO 5 INCHES HAS FALLEN IN THE VALLEY AS
  OF 10 PM. TOTAL SNOWFALL OF 6 TO 8 INCHES WILL OCCUR WITH
  LOCALLY HIGHER AMOUNTS POSSIBLE.

* WIND AND VISIBILITY...A SOUTH WIND OF 10 TO 20 MPH WILL COMBINE
  WITH SNOWFALL TO REDUCE THE VISIBILITY TO ONE HALF MILE AT TIMES
  IN THE OPEN AREAS NORTH OF THE TOWN JACKSON.

* IMPACTS...AREA ROADS WILL LIKELY BECOME SLICK WITH SNOWFALL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. IF YOU MUST
TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR
VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ023-191400-
/O.UPG.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
/O.NEW.KRIW.WS.W.0003.110119T0548Z-110119T1800Z/
STAR VALLEY-
INCLUDING THE CITIES OF...AFTON...ALPINE...THAYNE
1048 PM MST TUE JAN 18 2011

...WINTER STORM WARNING IN EFFECT UNTIL 11 AM MST WEDNESDAY...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A WINTER
STORM WARNING FOR HEAVY SNOW WHICH IS IN EFFECT UNTIL 11 AM MST
WEDNESDAY. THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT.

* SUMMARY AND TIMING...SNOW WILL OCCUR...MODERATE TO HEAVY AT
  TIMES THROUGH 5 AM. THEN LIGHT SNOW WILL OCCUR THE REST OF
  WEDNESDAY MORNING. SNOWFALL RATES OF 1 INCH PER HOUR WILL OCCUR
  IN HEAVY SNOW.

* SNOW ACCUMULATIONS...SNOWFALL OF 3 TO 5 INCHES HAS OCCURRED IN
  THE STAR VALLEY AS OF 10 PM. TOTAL SNOWFALL OF 6 TO 9 INCHES
  WILL OCCUR WITH LOCALLY HIGHER AMOUNTS POSSIBLE.

* WIND AND VISIBILITY...AREAS OF SOUTH WIND AT 10 TO 20 MPH COMBINED
  WITH SNOWFALL WILL REDUCE THE VISIBILITY TO ONE HALF MILE AT
  TIMES.

* IMPACTS...AREA ROADS WILL BECOME SLICK WITH SNOWFALL. DRIFTING
  SNOW WILL ALSO IMPACT ROADWAYS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN
AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ012-191400-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
TETON AND GROS VENTRE MOUNTAINS-
1048 PM MST TUE JAN 18 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY. 

* SUMMARY AND TIMING...MODERATE TO HEAVY SNOW WILL OCCUR IN THIS
  AREA THROUGH 5 AM...THEN DECREASE TO LIGHT SNOW THROUGH
  WEDNESDAY MORNING. SNOWFALL RATES OF AN INCH OR MORE PER HOUR IS
  LIKELY IN HEAVY SNOW.

* SNOW ACCUMULATIONS...SNOWFALL OF 4 TO 7 INCHES HAS OCCURRED
  ABOVE 8500 FEET IN THE TETONS AS OF 10 PM. TOTAL SNOWFALL OF 6
  TO 12 INCHES WILL OCCUR. 

* WIND AND VISIBILITY...A WEST WIND OF 25 TO 35 MPH WITH GUSTS TO
  45 MPH WILL OCCUR WITH BLOWING SNOW AND VERY LOW VISIBILITY. 

* IMPACTS...TRAVEL OVER TETON AND TOGWOTEE PASS WILL BE IMPACTED 
  BY SNOW COVERED ROADS AND REDUCED VISIBILITY. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ024-191400-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
SALT RIVER AND WYOMING RANGES-
1048 PM MST TUE JAN 18 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY. 

* SUMMARY AND TIMING...SNOW WILL OCCUR...MODERATE TO HEAVY AT
  TIMES THROUGH 6 AM...THEN TAPER OFF TO LIGHT SNOW FOR WEDNESDAY
  MORNING. SNOWFALL RATES OF AN INCH OR MORE PER HOUR WILL OCCUR
  IN HEAVY SNOW. 

* SNOW ACCUMULATIONS...SNOWFALL OF 1 TO 4 INCHES HAS OCCURRED AS
  OF 10 PM. STORM TOTAL SNOWFALL WILL RANGE FROM 6 TO 12 INCHES.

* WIND AND VISIBILITY...A WEST WIND OF 25 TO 35 MPH WILL OCCUR
  OVER THE SUMMITS WITH BLOWING SNOW AND VERY LOW VISIBILITY

* IMPACTS...ANYONE WITH TRAVEL PLANS IN THE SALT OR WYOMING RANGES
  SHOULD BE PREPARED FOR SNOW...GUSTY WIND AND FALLING
  TEMPERATURES. AREA ROADS WILL BE SLICK AND SNOW PACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ025-191400-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
UPPER GREEN RIVER BASIN FOOTHILLS-
INCLUDING THE CITY OF...PINEDALE
1048 PM MST TUE JAN 18 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST
WEDNESDAY. 

* SUMMARY AND TIMING...SNOW WILL OCCUR OVERNIGHT INTO WEDNESDAY
  MORNING. THE HEAVIEST PERIOD OF SNOWFALL WILL OCCUR FROM
  MIDNIGHT UNTIL 6 AM. THEN LIGHT SNOW WILL OCCUR THE REST OF WEDNESDAY
  MORNING.

* SNOW ACCUMULATIONS...2 INCHES AROUND PINEDALE WITH 3 TO 5 
  INCHES FROM CORA TO BONDURANT. 

* VISIBILITY...UNDER ONE MILE AT TIMES.

* IMPACTS...HIGHWAY 189 AND 191 WILL BECOME SLICK AND SNOW PACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$
3 follow-up statements
798 
WWUS45 KRIW 190953
WSWRIW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
253 AM MST WED JAN 19 2011

...STORM SYSTEM TO IMPACT THE WEST THROUGH EARLY AFTERNOON...

.A STORM SYSTEM WILL MOVE SOUTHEAST INTO SOUTHWEST WYOMING THIS MORNING.
SNOW WILL OCCUR...MODERATE TO HEAVY AT TIMES THROUGH 5 AM ...THEN
TAPERING OFF TO LIGHT SNOW IN THE WEST. EAST OF THE
DIVIDE...A PERIOD OF MODERATE TO HEAVY SNOW WILL OCCUR DURING THE
MORNING HOURS ALONG THE LANDER FOOTHILLS.

WYZ013-191800-
/O.CON.KRIW.WS.W.0003.000000T0000Z-110119T1800Z/
JACKSON HOLE-
INCLUDING THE CITY OF...JACKSON
253 AM MST WED JAN 19 2011

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...SNOW WILL CONTINUE THIS MORNING. THE
  HEAVIEST PERIOD OF SNOWFALL WILL OCCUR THROUGH 5 AM...THEN TAPER
  OFF TO LIGHT SNOW THROUGH LATE MORNING. SNOWFALL RATES OF 1 INCH
  PER HOUR ARE LIKELY IN HEAVY SNOW.

* SNOW ACCUMULATIONS...5 TO 6 INCHES HAS FALLEN IN THE VALLEY.
  TOTAL SNOWFALL OF 6 TO 8 INCHES WILL OCCUR WITH LOCALLY HIGHER
  AMOUNTS POSSIBLE.

* WIND AND VISIBILITY...A SOUTH WIND OF 10 TO 20 MPH WILL 
  COMBINE WITH SNOWFALL TO REDUCE THE VISIBILITY TO ONE HALF 
  MILE AT TIMES IN THE OPEN AREAS NORTH OF THE TOWN JACKSON. 

* IMPACTS...AREA ROADS WILL BECOME SNOW PACKED AND SLICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. IF YOU MUST
TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR
VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ023-191800-
/O.CON.KRIW.WS.W.0003.000000T0000Z-110119T1800Z/
STAR VALLEY-
INCLUDING THE CITIES OF...AFTON...ALPINE...THAYNE
253 AM MST WED JAN 19 2011

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...SNOW WILL OCCUR...MODERATE TO HEAVY AT
  TIMES THROUGH 7 AM. THEN LIGHT SNOW WILL OCCUR THE REST OF THE
  MORNING. SNOWFALL RATES OF 1 INCH PER HOUR WILL OCCUR IN HEAVY
  SNOW.

* SNOW ACCUMULATIONS...4 TO 6 INCHES HAS FALLEN IN THE STAR VALLEY.
  TOTAL SNOWFALL OF 6 TO 9 INCHES WILL OCCUR WITH LOCALLY HIGHER
  AMOUNTS POSSIBLE.

* WIND AND VISIBILITY...AREAS OF SOUTH WIND AT 10 TO 20 MPH 
  COMBINED WITH SNOWFALL WILL REDUCE THE VISIBILITY TO ONE HALF 
  MILE AT TIMES. 

* IMPACTS...AREA ROADS WILL BECOME SLICK WITH SNOWFALL. DRIFTING 
  SNOW WILL ALSO IMPACT ROADWAYS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN
AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ018-191815-
/O.EXB.KRIW.WW.Y.0003.110119T1000Z-110119T2100Z/
LANDER FOOTHILLS-
INCLUDING THE CITY OF...LANDER
253 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOWFALL...WHICH IS IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON.

* SUMMARY AND TIMING...SNOW WILL DEVELOP EARLY THIS MORNING AND
  CONTINUE...MODERATE TO HEAVY AT TIMES...THROUGH EARLY AFTERNOON.

* SNOW ACCUMULATIONS...SNOWFALL OF 2 TO 4 INCHES IN EXPECTED IN
  THE LANDER AREA.

* WIND AND VISIBILITY...NORTHERLY WIND OF UP TO 10 MPH IS EXPECTED
  WITH VISIBILITY REDUCED TO UNDER ONE MILE AT TIMES DURING
  HEAVIER SNOW.

* IMPACTS...HAZARDOUS TRAVEL CAN BE EXPECTED AT TIMES ALONG
  HIGHWAY 287 AND 789 IN AND AROUND LANDER AS VISIBILITY IS
  REDUCED AND ROADS BECOME SNOW PACKED AND SLICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ012-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
TETON AND GROS VENTRE MOUNTAINS-
253 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...MODERATE TO HEAVY SNOW WILL OCCUR IN THIS
  AREA THROUGH 5 AM...THEN DECREASE TO LIGHT SNOW THROUGH THE REST
  OF THE MORNING. SNOWFALL RATES OF AN INCH OR MORE PER HOUR ARE
  LIKELY IN HEAVY SNOW.

* SNOW ACCUMULATIONS...SNOWFALL OF 8 TO 12 INCHES HAS OCCURRED
  ABOVE 8500 FEET IN THE TETONS. TOTAL SNOWFALL OF 10 TO 15 INCHES
  WILL OCCUR.

* WIND AND VISIBILITY...A WEST WIND OF 20 TO 30 MPH WITH GUSTS TO
  40 MPH WILL OCCUR WITH BLOWING SNOW AND VERY LOW VISIBILITY.

* IMPACTS...TRAVEL OVER TETON AND TOGWOTEE PASS WILL BE IMPACTED 
  BY SNOW COVERED ROADS AND REDUCED VISIBILITY. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ024-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
SALT RIVER AND WYOMING RANGES-
253 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...SNOW WILL OCCUR...MODERATE TO HEAVY AT
  TIMES THROUGH 7 AM...THEN TAPER OFF TO LIGHT SNOW THROUGH THE MORNING.
  SNOWFALL RATES OF AN INCH OR MORE PER HOUR WILL OCCUR IN HEAVY
  SNOW.

* SNOW ACCUMULATIONS...SNOWFALL OF 4 TO 7 INCHES HAS FALLEN
  THROUGH 2 AM. STORM TOTAL SNOWFALL WILL RANGE FROM 6 TO 12 INCHES.

* WIND AND VISIBILITY...A WEST WIND OF 25 TO 35 MPH WILL OCCUR 
  OVER THE SUMMITS WITH BLOWING SNOW AND VERY LOW VISIBILITY 

* IMPACTS...ANYONE WITH TRAVEL PLANS IN THE SALT OR WYOMING 
  RANGES SHOULD BE PREPARED FOR SNOW...GUSTY WIND AND FALLING 
  TEMPERATURES. AREA ROADS WILL BE SLICK AND SNOW PACKED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ025-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
UPPER GREEN RIVER BASIN FOOTHILLS-
INCLUDING THE CITY OF...PINEDALE
253 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...SNOW WILL OCCUR THROUGH THE MORNING. THE
  HEAVIEST PERIOD OF SNOWFALL WILL OCCUR FROM THROUGH 7 AM. THEN
  LIGHT SNOW WILL OCCUR THE REST OF THE MORNING.

* SNOW ACCUMULATIONS...2 INCHES AROUND PINEDALE WITH 3 TO 5 
  INCHES FROM CORA TO BONDURANT. 

* VISIBILITY...UNDER ONE MILE AT TIMES.

* IMPACTS...HIGHWAY 189 AND 191 WILL BECOME SLICK AND SNOW 
  PACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$
962 
WWUS45 KRIW 191213
WSWRIW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
513 AM MST WED JAN 19 2011

...WINTER STORM TO IMPACT PARTS OF THE AREA THROUGH EARLY AFTERNOON...

.A STORM SYSTEM WILL CONTINUE PUSH SOUTHEAST ACROSS SOUTHWEST WYOMING
THIS MORNING. LIGHT SNOW WILL CONTINUE ACROSS MUCH OF WESTERN
WYOMING THIS MORNING...BEFORE TAPERING OFF BY LATE MORNING. A
PERIOD OF LIGHT TO MODERATE SNOW IS EXPECTED ACROSS CENTRAL
WYOMING AS A COLD FRONT PUSHES SOUTH ACROSS THE AREA. THE HEAVIEST
SNOWFALL IS EXPECTED ACROSS THE LANDER FOOTHILLS WHERE 2 TO 4
INCHES IS EXPECTED...WHILE THE REST OF THE LOWER ELEVATIONS
ACROSS CENTRAL WYOMING COULD SEE 1 TO 3 INCHES OF SNOWFALL WITH
THIS SYSTEM. MOST OF THE SNOWFALL WILL OCCUR BY LATE MORNING.

WYZ013-191800-
/O.CON.KRIW.WS.W.0003.000000T0000Z-110119T1800Z/
JACKSON HOLE-
INCLUDING THE CITY OF...JACKSON
513 AM MST WED JAN 19 2011

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...LIGHT SNOW WILL CONTINUE THIS MORNING.

* SNOW ACCUMULATIONS...4 TO 8 INCHES HAS FALLEN ACROSS JACKSON
  HOLE...WITH ISOLATED LOCATIONS REPORTING NEAR A FOOT OF SNOW. AN
  ADDITIONAL ONE TO TWO INCHES ARE POSSIBLE.

* VISIBILITY...UNDER A MILE AT TIMES.

* IMPACTS...AREA ROADS WILL BE SNOWPACKED AND SLICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. IF YOU MUST
TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR
VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ023-191800-
/O.CON.KRIW.WS.W.0003.000000T0000Z-110119T1800Z/
STAR VALLEY-
INCLUDING THE CITIES OF...AFTON...ALPINE...THAYNE
513 AM MST WED JAN 19 2011

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...LIGHT SNOW WILL CONTINUE THIS MORNING.

* SNOW ACCUMULATIONS...4 TO 8 INCHES HAS FALLEN ACROSS STAR
  VALLEY...WITH AREAS AROUND THAYNE REPORTING 10 INCHES SO FAR. AN
  ADDITIONAL ONE TO TWO INCHES ARE POSSIBLE.

* WIND AND VISIBILITY...UNDER A MILE AT TIMES.

* IMPACTS...AREA ROADS WILL BE SLICK AND SNOWPACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING.  SIGNIFICANT AMOUNTS OF
SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN
AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

&&

$$

WYZ012-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
TETON AND GROS VENTRE MOUNTAINS-
513 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...LIGHT TO MODERATE SNOW WILL CONTINUE THIS MORNING.

* SNOW ACCUMULATIONS...6 TO 12 INCHES HAS OCCURRED ACROSS THE
  TETON AND GROS VENTRE MOUNTAINS OVERNIGHT. THE HEAVIEST SNOWFALL
  AMOUNTS OCCURRED OVER THE SOUTHERN TETONS...WHERE OVER A FOOT OF
  SNOW FELL. AN ADDITIONAL INCH OR TWO OF SNOW IS EXPECTED. 

* VISIBILITY...UNDER A MILE AT TIMES.

* IMPACTS...TRAVEL OVER TETON AND TOGWOTEE PASSES WILL BE IMPACTED 
  BY SNOW COVERED ROADS AND REDUCED VISIBILITY. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ018-192100-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T2100Z/
LANDER FOOTHILLS-
INCLUDING THE CITY OF...LANDER
513 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON. 

* SUMMARY AND TIMING...SNOW WILL DEVELOP BY 7 AM. A PERIOD OF
  MODERATE TO HEAVY SNOWFALL IS EXPECTED BETWEEN 7 AM AND 10
  AM...WITH A STEADY LIGHT SNOW THROUGH EARLY AFTERNOON. 

* SNOW ACCUMULATIONS...SNOWFALL OF 2 TO 4 INCHES IN EXPECTED IN 
  THE LANDER AREA. 

* VISIBILITY...UNDER A HALF A MILE AT TIMES.

* IMPACTS...HAZARDOUS TRAVEL CAN BE EXPECTED AT TIMES ALONG
  HIGHWAY 287 AND 789 IN AND AROUND LANDER AS VISIBILITY IS
  REDUCED AND ROADS BECOME SNOWPACKED AND SLICK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ024-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
SALT RIVER AND WYOMING RANGES-
513 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...LIGHT TO MODERATE SNOW WILL CONTINUE THIS MORNING.

* SNOW ACCUMULATIONS...SNOWFALL OF 5 TO 8 INCHES HAS FALLEN SO
  FAR...WITH SNOWFALL TOTALS GENERALLY BETWEEN 6 AND 12 INCHES.

* VISIBILITY...UNDER A MILE AT TIMES.

* IMPACTS...AREA ROADS WILL BE SLICK AND SNOWPACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

WYZ025-191800-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
UPPER GREEN RIVER BASIN FOOTHILLS-
INCLUDING THE CITY OF...PINEDALE
513 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING. 

* SUMMARY AND TIMING...LIGHT SNOW WILL CONTINUE THIS MORNING. 

* SNOW ACCUMULATIONS...2 INCHES AROUND PINEDALE WITH 3 TO 5 
  INCHES FROM CORA TO BONDURANT. 

* VISIBILITY...UNDER ONE MILE AT TIMES.

* IMPACTS...HIGHWAY 189 AND 191 WILL BE SLICK AND SNOWPACKED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

21
966 
WWUS45 KRIW 191538
WSWRIW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
838 AM MST WED JAN 19 2011

...WINTER STORM TO IMPACT PARTS OF THE AREA THROUGH EARLY
AFTERNOON...

.A STORM SYSTEM WILL CONTINUE TO PUSH SOUTHEAST ACROSS SOUTHWEST
WYOMING THIS MORNING.  LIGHT SNOW WILL CONTINUE ACROSS CENTRAL
WYOMING THROUGH EARLY AFTERNOON BEFORE TAPERING OFF. 

WYZ013-023-191645-
/O.CAN.KRIW.WS.W.0003.000000T0000Z-110119T1800Z/
JACKSON HOLE-STAR VALLEY-
INCLUDING THE CITIES OF...JACKSON...AFTON...ALPINE...THAYNE
838 AM MST WED JAN 19 2011

...WINTER STORM WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS CANCELLED THE WINTER
STORM WARNING. 

SNOWFALL HAS TAPERED OFF ACROSS THE AREA...THEREFORE THE WINTER
STORM WARNING HAS BEEN CANCELED. ADDITIONAL SNOW SHOWERS ARE
POSSIBLE THROUGH THE DAY. HOWEVER...LITTLE ADDITIONAL
ACCUMULATION IS EXPECTED.

$$

WYZ012-024-025-191645-
/O.CAN.KRIW.WW.Y.0003.000000T0000Z-110119T1800Z/
TETON AND GROS VENTRE MOUNTAINS-SALT RIVER AND WYOMING RANGES-
UPPER GREEN RIVER BASIN FOOTHILLS-
INCLUDING THE CITY OF...PINEDALE
838 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

SNOWFALL HAS TAPERED OFF ACROSS THE AREA...THEREFORE THE WINTER
WEATHER ADVISORY HAS BEEN CANCELED. ADDITIONAL SNOW SHOWERS ARE POSSIBLE
THROUGH THE DAY. HOWEVER...LITTLE ADDITIONAL ACCUMULATION IS
EXPECTED.

$$

WYZ018-192100-
/O.CON.KRIW.WW.Y.0003.000000T0000Z-110119T2100Z/
LANDER FOOTHILLS-
INCLUDING THE CITY OF...LANDER
838 AM MST WED JAN 19 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 PM MST THIS
AFTERNOON. 

* SUMMARY AND TIMING...OCCASIONAL LIGHT SNOW WILL CONTINUE THROUGH EARLY
  AFTERNOON BEFORE ENDING.

* SNOW ACCUMULATIONS...SNOWFALL OF 2 TO 4 INCHES IN EXPECTED IN 
  THE LANDER AREA. 

* VISIBILITY...UNDER A HALF A MILE AT TIMES.

* IMPACTS...HAZARDOUS TRAVEL CAN BE EXPECTED AT TIMES ALONG 
  HIGHWAY 287 AND 789 IN AND AROUND LANDER AS VISIBILITY IS 
  REDUCED AND ROADS BECOME SNOWPACKED AND SLICK. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Riverton, WY wrote its last area forecast discussion before this winter storm warning went out at Jan 18, 1:54 PM MST, 8 hours 54 minutes earlier.

Area forecast discussion, Jan 18, 1:54 PM MST, 8 hours 54 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
154 PM MST TUE JAN 18 2011

SHORT TERM...TONIGHT THROUGH FRIDAY
NEXT SYSTEM IS MOVING THROUGH WA AND SWRN B.C. AND SHOULD START
IMPACTING THE FAR WEST THIS EVENING. ISENTROPIC LIFT DEVELOPS
INCREASES OVER THE NEXT FEW HOURS IN ADVANCE OF THE UPPER LEVEL
SUPPORT. QG FORCING BEGINS TO INCREASE...LAPSE RATES STEEPEN AND
POSSIBLE INTERACTION OF TWO JET STREAKS ADDS UP TO A PERIOD OF
MODERATE TO LOCALLY HEAVY SNOW IN THE FAR WEST TONIGHT WITH
LIGHTER SNOWS INTO WEDNESDAY MORNING. WILL ISSUE WINTER WX
ADVISORIES FOR THE TETONS...JACKSON AND STAR
VALLEYS...SALT/WYOMING RANGES AND THE BONDURANT TO PNA ZONE FOR
TONIGHT THROUGH 18Z WED.

AT THE SAME TIME...THE ARCTIC BOUNDARY IS SAGGING SWD INTO JOHNSON
COUNTY THIS AFTERNOON WITH TEMPS DROPPING INTO THE LOWER 20S AT BYG
AFTER A MORNING HIGH IN THE MID 30S. THIS FRONTAL BOUNDARY WILL
CONTINUE TO SAG SOUTH THIS EVENING WITH A REINFORCING SHOT COMING IN
WEDNESDAY MORNING AS THE TROUGH MOVES IN ALOFT. COMBINATION OF THIS
FRONT AND SOME GENTLE ISENTROPIC UPGLIDE OVER THE BOUNDARY SHOULD
PRODUCE WIDESPREAD LIGHT SNOW IN OUR NERN ZONES TONIGHT WITH A
CHANCE FURTHER SOUTH. FRONT PUSHES THROUGH ALL OF CENTRAL WYO IN THE
12Z TO 15Z TIMEFRAME WITH SNOW FOLLOWING QUICKLY. COMBINATION OF QG
FORCING AND TAIL END OF A JET STREAK COMBINED WITH DECENT UPSLOPE
SHOULD PRODUCE A PERIOD OF LIGHT TO MODERATE SNOW IN THE CENTRAL
ZONES WEDNESDAY MORNING WITH LIGHTER SNOW OR FLURRIES IN THE
AFTERNOON. COULD POSSIBLE NEED AN ADVISORY FOR THE LANDER FOOTHILLS
IF SNOW RATIO IS IN THE 18-1 RATIO AS THE HPC MEAN INDICATES AS WE
EXPECT ABOUT .20 TO .25 INCHES OF LIQUID. THE SOUTH SIDE OF CASPER
WILL HAVE TO BE WATCHED ALSO BUT MOST OF THE AREA WILL GENERALLY SEE
1 TO 2 INCHES. THE ADJACENT E SLOPE OF THE WINDS COULD ALSO SEE A
QUICK SHOT OF 4-8 INCHES WITH 3 TO 6 ON CPR MTN. THE ODDS WILL
INCREASE FOR CPR MTN AND CPR IF SOME LIGHT SNOW DEVELOPS AHEAD OF
THE MAIN FROPA WED MORNING. THE GFS INDICATES THE BEST CHANCE OF
THIS AFTER MIDNIGHT. SOME LIGHT SNOW WILL DEVELOP ACROSS THE I80
CORRIDOR LATER TONIGHT AND THEN THE FRONT WILL MOVE INTO THE ERN
PART OF SWEETWATER COUNTY WEDNESDAY AFTERNOON FOR CONTINUED LIGHT
SNOW. QUICK SHOT FOR MOST AREAS AND WE'LL NEED THE UPPER SUPPORT TO
HIT ANY POTENTIAL ADVSRY NUMBERS. ALSO A CHANCE OF SOME EVENING SNOW
SHOWERS THAT THE NAM IS SHOWING AND TO A LESSER EXTENT THE GFS/ECMWF.
HOWEVER...THE MODELS ARE ALL WARMING THE TO MID TO UPPER LEVEL TEMPS
AFTER 00Z SO LAPSE RATES SHOULD DECREASE WHICH IS A NEGATIVE. ADDED
SOME CHANCE POPS DOWNWIND OF OUR FAVORED NW FAVORED AREAS BUT
NOTHING TO MUCH YET.

AS THIS SYSTEM EXITS...THE NEXT JET MOVES QUICKLY IN WITH INCREASING
BARRIER FLOW INTO THE ABSAROKAS THURSDAY INTO THURSDAY NIGHT.
POTENTIAL MOUNTAIN WAVE AND MORE CERTAIN GAP FLOW EVENT WILL LIKELY
DEVELOP ON THURSDAY AND PEAK THURSDAY NIGHT. CRANKED UP THE WINDS
CONSIDERABLY IN THIS AREA. MORE ISENTROPIC LIFT WILL BRING SOME
LIGHT SNOW BACK INTO THE MTNS THURSDAY INTO FRIDAY BUT RIGHT NOW IT
LOOKS LIGHT. SHARPLY COLDER BEHIND OUR SYSTEM WEDNESDAY NIGHT WITH
BITTER COLD LOWS OUT WEST AND MORE LIKE JANUARY AGAIN JUST ABOUT
EVERYWHERE. COLD DOESN'T LOOK TO STICK AROUND REAL LONG BUT A QUICK
CHANGE BACK AFTER A MILD COUPLE DAYS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY

MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT WITH NORTHWEST FLOW OVER
THE REGION...AND A COUPLE OF CLIPPER SYSTEMS AFFECTING THE AREA NEXT
WEEKEND. EARLY FRIDAY...A SHORTWAVE TROUGH IS PROJECTED TO BE OFF
THE BRITISH COLUMBIA COAST.  THIS SYSTEM IS EXPECTED TO DIVE
SOUTHEAST IN THE NORTHWEST FLOW INTO THE PACIFIC NORTHWEST FRIDAY.
THIS SYSTEM IS EXPECTED THEN TO PUSH SOUTHEAST ACROSS THE
INTERMOUNTAIN WEST FRIDAY NIGHT...ALLOWING SNOWFALL TO BREAK OUT
ACROSS THE WEST/NORTHWEST. ON SATURDAY AND SATURDAY NIGHT THIS
SYSTEM IS EXPECTED TO CONTINUE DIVING SOUTHEAST ACROSS THE
CENTRAL/SOUTHERN ROCKIES. THE ASSOCIATED COLD FRONT IS EXPECTED TO
PUSH ACROSS THE REGION SATURDAY/SATURDAY EVENING. MEDIUM RANGE
MODELS ARE A BIT FARTHER NORTHEAST WITH THIS SYSTEM TONIGHT...THAN
LAST NIGHT RESULTING IN A BETTER CHANCE FOR SNOWFALL ESPECIALLY
EAST OF THE DIVIDE SATURDAY/SATURDAY NIGHT.

ON THE HEELS OF THE FIRST CLIPPER SYSTEM SATURDAY...ANOTHER CLIPPER
IS PROJECTED BY MEDIUM RANGE MODELS TO BE IN THE GENERAL NORTHWEST
FLOW SUNDAY/SUNDAY NIGHT.  HOWEVER...THEY DISAGREE ON THE TRACK.
THE 00Z GEM IS BY THE FARTHEST WEST TAKING IT ACROSS IDAHO/SW
WYOMING...WHILE THE GFS AND ECMWF HAVE BEEN A BIT SLOWER AND
TRACKING THIS SYSTEM ACROSS THE NORTHERN HIGH PLAINS...AND THEN
BECOMING CLOSED OFF ACROSS THE MIDWEST MONDAY. TRENDED TOWARD THE
GFS AND ECMWF TRACK WITH THE SECOND SYSTEM...WHICH WOULD RESULT IN
MUCH LOWER CHANCE FOR SNOWFALL. IT ALSO HAS LESS MOISTURE TO WORK
WITH THAN THE FIRST SYSTEM.

MEDIUM RANGE MODELS THEN TRY TO BUILD IN A RIDGE MONDAY NIGHT AND
TUESDAY ACROSS THE AREA...BUT PREVIOUS MODEL RUNS HAVE SHOWN THE
NORTHWEST FLOW CONTINUING. ALTHOUGH THE 00Z ECMWF DOES DEVELOP A
RIDGE MONDAY NIGHT/TUESDAY...IT IS ALSO BREAKS THE RIDGE DOWN WITH
ANOTHER SHORTWAVE TROUGH AFFECTING THE FORECAST AREA TUESDAY
NIGHT/WEDNESDAY...WHILE THE GFS HOLDS ON TO THE RIDGE.

HAVE INCREASED POPS CONSIDERABLY FRIDAY NIGHT THROUGH SATURDAY NIGHT
ACROSS THE AREA...AS CONFIDENCE IS GROWING ON THIS CLIPPER
SYSTEM...BUT KEPT POPS LOW FOR THE REST OF THE EXTENDED DUE MODEL
INCONSISTENCIES.

AVIATION...
THE NEXT STORM WILL IMPACT WYOMING TONIGHT AND WEDNESDAY.  LIGHT
SNOW WILL DEVELOP IN THE WEST THIS EVENING WITH MVFR CIGS AND VSBYS
EXPECTED.  LCL IFR CIGS AND VSBYS ARE POSSIBLE UNDER MODERATE TO
HEAVY SNOW.  WIDESPREAD MTN OBSCURATIONS WILL ACCOMPANY THE SNOW.
THE SNOW IN THE WEST WILL LET UP IN THE LATE MORNING...WITH SHOWERS
PERSISTING ESPECIALLY OVER THE MOUNTAINS THROUGHOUT THE DAY.  A COLD
FRONT WILL MOVE INTO NORTHERN WYOMING EARLY WEDNESDAY MORNING AND
INTO CENTRAL WYOMING BY MID/LATE MORNING.  LIGHT SNOW ACCOMPANIES
THE FRONT WITH MVFR CIGS AND VSBYS.  TAF SITES LOCATED ADJACENT TO
NORTH TO EAST FACING MOUNTAIN SLOPES WILL SEE EXTENDED PERIODS OF
-SN...WHILE THOSE AWAY FROM THE MOUNTAIN COULD SEE 4 TO 6 HOURS
WORTH.  A COLD FRONT THAT BACKED INTO JOHNSON COUNTY THIS MORNING
WILL REMAIN WITH SOME LIGHT SNOW AND IFR CIGS POSSIBLE THERE THIS
EVENING AND TOMORROW MORNING...BEFORE THE PACIFIC COLD FRONT MOVES
IN.

FIRE WEATHER...
ANOTHER STORM SYSTEM WILL BRING WIDESPREAD SNOW TO THE WEST
TONIGHT AND WEDNESDAY MORNING. EAST OF THE DIVIDE...ANOTHER COLD
FRONT WILL SAG SOUTHWARD OVERNIGHT WITH WITH LIGHT SNOW SPREADING
SOUTHWARD ON GUSTY NORTH WINDS. THE SYSTEM WILL MOVE OFF WEDNESDAY
NIGHT WITH A CLEARING SKY AND SHARPLY COLDER TEMPERATURES. WINDS
WILL RETURN TO THE WIND CORRIDOR AND CODY FOOTHILLS THURSDAY INTO
THURSDAY NIGHT.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM MST
WEDNESDAY WYZ012-013-023>025.

&&

SHORT TERM...SKRBAC
LONG TERM...WM
AVIATION...TWB
FIRE WEATHER...SKRBAC
Hazardous weather outlook, Jan 18, 2:01 PM MST, 8 hours 47 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RIVERTON WY
201 PM MST TUE JAN 18 2011

WYZ001>020-022>030-191200-
ABSAROKA MOUNTAINS-BIGHORN MOUNTAINS SOUTHEAST-
BIGHORN MOUNTAINS WEST-CASPER MOUNTAIN-CODY FOOTHILLS-
EAST SWEETWATER COUNTY-FLAMING GORGE-
GREEN MOUNTAINS AND RATTLESNAKE RANGE-JACKSON HOLE-LANDER FOOTHILLS-
NATRONA COUNTY LOWER ELEVATIONS-NORTH BIG HORN BASIN-
NORTHEAST JOHNSON COUNTY-OWL CREEK AND BRIDGER MOUNTAINS-
ROCK SPRINGS AND GREEN RIVER-SALT RIVER AND WYOMING RANGES-
SOUTH LINCOLN COUNTY-SOUTHEAST BIG HORN BASIN-
SOUTHEAST JOHNSON COUNTY-SOUTHWEST BIG HORN BASIN-STAR VALLEY-
TETON AND GROS VENTRE MOUNTAINS-UPPER GREEN RIVER BASIN-
UPPER GREEN RIVER BASIN FOOTHILLS-UPPER WIND RIVER BASIN-
WIND RIVER BASIN-WIND RIVER MOUNTAINS EAST-WIND RIVER MOUNTAINS WEST-
YELLOWSTONE NATIONAL PARK-
201 PM MST TUE JAN 18 2011

...WINTER WEATHER ADVISORIES FOR MUCH OF FAR WESTERN WYOMING TONIGHT
THROUGH WEDNESDAY MORNING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING.

.DAY ONE...TODAY AND TONIGHT

A PACIFIC DISTURBANCE WILL MOVE INTO WESTERN WYOMING TONIGHT...
BRINGING A PERIOD OF MODERATE TO HEAVY SNOW.  EXPECT HAZARDOUS
DRIVING CONDITIONS WITH SNOW COVERED AND SLICK ROADS AND PERIODS OF
REDUCED VISIBILITY LATE TODAY AND OVERNIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

SNOWFALL FROM OUR FAR WESTERN WYOMING STORM WILL VARY FROM 2 TO 5
INCHES ACROSS THE LOWER ELEVATIONS WITH 5 TO 10 INCHES IN THE
MOUNTAINS.

A CANADIAN COLD FRONT WILL PUSH SOUTH ACROSS CENTRAL WYOMING EARLY
WEDNESDAY...USHERING IN MUCH COLDER TEMPERATURES AND PERIOD OF LIGHT
TO MODERATE SNOW.  EXPECT THE POTENTIAL FOR HAZARDOUS WINTER DRIVING
CONDITIONS OVER PORTIONS OF CENTRAL WYOMING WEDNESDAY. SNOWFALL WILL
GENERALLY RANGE FROM 1 TO 3 INCHES EAST OF THE DIVIDE.

ANOTHER WINTER STORM WILL AFFECT THE AREA NEXT WEEKEND. SNOW WITH
THIS SYSTEM IS EXPECTED TO AFFECT AREAS ALONG AND WEST OF THE DIVIDE
FRIDAY NIGHT INTO SATURDAY...SHIFTING EAST OF THE DIVIDE ON
SATURDAY. AT THIS TIME...SIGNIFICANT SNOWFALL COULD OCCUR OVER
WESTERN WYOMING FRIDAY NIGHT INTO SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT.

TEAM RIVERTON

In the hours before

Local storm report, Jan 18, 10:45 PM MST, 3 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1145 PM MDT TUE JAN 18 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1119 PM     SNOW             ALPINE                  43.18N 111.03W
01/18/2011  M2.00 INCHES     LINCOLN            WY   TRAINED SPOTTER

1119 PM     SNOW             JACKSON                 43.47N 110.75W
01/18/2011  M3.00 INCHES     TETON              WY   PUBLIC

1120 PM     SNOW             JACKSON                 43.47N 110.76W
01/18/2011  M5.00 INCHES     TETON              WY   PUBLIC

1120 PM     SNOW             AFTON                   42.72N 110.93W
01/18/2011  M5.00 INCHES     LINCOLN            WY   LAW ENFORCEMENT

1120 PM     SNOW             1 SE THAYNE             42.90N 110.98W
01/18/2011  M5.00 INCHES     LINCOLN            WY   PUBLIC

1121 PM     SNOW             WILSON                  43.49N 110.87W
01/18/2011  M4.00 INCHES     TETON              WY   TRAINED SPOTTER

1122 PM     SNOW             5 E MORAN               43.85N 110.42W
01/18/2011  M3.00 INCHES     TETON              WY   PUBLIC

1123 PM     SNOW             8.6 NNW JACKSON         43.58N 110.85W
01/18/2011  M4.00 INCHES     TETON              WY   PARK/FOREST SRVC

            JACKSON HOLE-BASE

1123 PM     HEAVY SNOW       9.3 NNW JACKSON         43.59N 110.84W
01/18/2011  M7.00 INCHES     TETON              WY   PARK/FOREST SRVC

            JACKSON HOLE-MID

1123 PM     SNOW             17.2 E THAYNE           42.97N 110.61W
01/18/2011  E4.00 INCHES     LINCOLN            WY   PARK/FOREST SRVC

            BLIND BULL SUMMIT

1123 PM     SNOW             14.3 E THAYNE           42.87N 110.71W
01/18/2011  E2.00 INCHES     LINCOLN            WY   PARK/FOREST SRVC

            BOX Y RANCH

1123 PM     SNOW             23 NW DUBOIS            43.73N 110.01W
01/18/2011  E3.00 INCHES     FREMONT            WY   PARK/FOREST SRVC

            BROOKS LAKE LODGE

1123 PM     HEAVY SNOW       9.9 NNW JACKSON         43.60N 110.85W
01/18/2011  M7.00 INCHES     TETON              WY   PARK/FOREST SRVC

            JACKSON HOLE-RAYMER

1123 PM     HEAVY SNOW       JACKSON HOLE-RENDEZVOUS 43.59N 110.87W
01/18/2011  M8.00 INCHES     TETON              WY   PARK/FOREST SRVC

1127 PM     HEAVY SNOW       1 S JACKSON             43.46N 110.76W
01/18/2011  M6.00 INCHES     TETON              WY   PUBLIC

            SNOW KING SKI AREA

&&

Nearby

Winter Storm Warnings in Wyoming, 2011Every winter storm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.