WInter So Far

• An animation of the snow gauge cam  on Star Valley Ranch has been created to show the daily changes of the winter season.  This particular period begins on October 24 and goes until December 31 2012.  Each image was captured around noon.  The frame rate is 2 days per second.  The animation will be updated again later this winter.

http://www.youtube.com/watch?v=VK4eqVln11U

Consequences of a Low Sun Angle

The first week of the New Year will see an absence of significant storm activity in the Star Valley region.  As a result the strong valley inversions that form with the long nights will remain through the afternoon as light winds and the low sun angle will  be insufficient to remove them.

Anyone who visits to the Salt Lake Valley with these inversions in place could experience trapped pollution and gloomy skies.  Jim Steenburgh has issued an interesting blog on the consequences of low sun angle and a stagnant weather pattern. 

Blessings and Curses of the Low Angle Sun

By Jim S

The sun just above Mt. Baldy shortly after noon today

Typically in Utah, the greatest threats to snow are wind and sun, so there's nothing better than a good early season snowpack combined with a low-angle sun like we have now.  Only on the warmest days can the sun do damage this time of year, so powder frequently lingers for days on most aspects in the backcountry provided it isn't trashed by the wind.  That doesn't happen in March, when the sun is almost always bad for south and west aspects and sometimes can be damaging to all but the steepest, north-facing slopes.

While the low-angle sun is a blessing for backcountry skiing, it is a curse for valley residents.  It doesn't provide enough energy to burn off cold pools (a.k.a., inversions) that form over the Salt Lake Valley and other low-elevation regions of Utah.  This is especially true when there is a fresh snow cover, which reflects a significant fraction of what little sun we get back to space.

We have just exited a fairly stormy pattern, so while there is a touch of smog over the valley, the pollution isn't too bad yet.

Salt Lake Valley from Alta

That will change in the coming days as we settle into a more stagnant pattern.  There are a couple of weak systems that brush by early next week, but it appears they will stir things up only a little, with Salt Lakers eventually seeing the worst air quality thus far this season as the week progresses.

2012 Precipitation and Temperatures

Although it is a couple days early, little in the way of additional precipitation is expected by the end of the year.  A summary of the precipitation has been compiled for two of the observation sites in Star Valley.  One of them is located on Star Valley Ranch and the other is about a mile and a half southeast of Thayne.

The normal annual precipitation for Star Valley is between 21 and 25 inches.  2012 ended up a little below the normal.  However the summer of 2012 was one of the driest on record.  Fortunately the pattern changed and the Fall was quite moist.  Most noticeably, December produced well over 3 inches of precipitation at both stations along with over 4 feet of snow.

Following is a table for the two stations for the 2012 precipitation.

An additional snowfall observer located 2 miles northeast of Etna reports the following  2012 totals.

            January         20.25”

            February       22.5

            March           10.75

            October          9.5

            November     11.5

            December      45.5 

                        

Merry Christmas-Snow Update

The following is an update on the snowfall across Western Wyoming as of Christmas Eve from the  Riverton Forecast Office

Christmas Snowfall Information - Updated 8 PM Monday

Snow Data | Past Christmas Data | 2012 Christmas Forecast | Contact Us

Excitement across Wyoming and our nation continues to grow as Christmas quickly approaches. What are your chances for the desired "White Christmas?" The National Climatic Data Center has created a probability graphic of having a 1" snow depth on Christmas using data between 1981 and 2010 (image on the left).  The National Operational Hydrologic Remote Sensing Center estimates snow depth across the entire U.S. every day through many different data sources.  The image on the right shows the approximate locations where snow is located across Wyoming.  Click on either image to enlarge them.

Historical Probability of a White Christmas

Locations Covered by
Snow Prior to Monday

Snowfall Amounts through 5 PM Monday

County	Station Name	Snowfall
Big Horn	Shell Creek Snotel	2
Fremont	South Pass Snotel	4
Fremont	St. Lawrence Alt Snotel	4
Fremont	Little Warm Snotel	2
Fremont	Burroughs Creek Snotel	2
Fremont	Cold Springs Snotel	2
Fremont	Townsend Creek Snotel	2
Fremont	Deer Park Snotel	2
Fremont	Hobbs Park Snotel	2
Fremont	Brooks Lake Lodge	1
Johnson	Cloud Peak Reservoir Snotel	4
Johnson	Hansen Sawmill Snotel	2
Johnson	Little Goose Snotel	2
Johnson	Soldier Park Snotel	2
Lincoln	Willow Creek Snotel	10
Lincoln	Indian Creek Snotel	8
Lincoln	Kelley Ranger Station Snotel	8
Lincoln	Blind Bull Summit Snotel	6
Lincoln	Hams Fork Snotel	6
Lincoln	Salt River Summit Snotel	6
Lincoln	Spring Creek Divide Snotel	6
Lincoln	Cottonwood Creek Snotel	4
Lincoln	5 SSE Smoot	4
Lincoln	Smoot	3.7
Lincoln	2 SE Thayne	3
Lincoln	Box Y Ranch	3
Lincoln	Afton	1.8
Lincoln	Fossil Butte	1
Park	Blackwater Snotel	6
Park	Evening Star Snotel	6
Park	Marquette Snotel	4
Park	Wolverine Snotel	4
Park	Beartooth Lake Snotel	4
Park	Kirwin Snotel	2
Park	Pahaska	2
Park	Younts Peak Snotel	2
Sublette	Triple Peak Snotel	8
Sublette	Loomis Park Snotel	6
Sublette	Big Sandy Opening Snotel	6
Sublette	Larsen Creek Snotel	6
Sublette	New Fork Lake Snotel	6
Sublette	East Rim Divide Snotel	6
Sublette	Snider Basin Snotel	6
Sublette	8 N Daniel	5.5
Sublette	Elkhart Park G.S. Snotel	4
Sublette	Gunsite Pass Snotel	4
Sublette	Kendall Ranger Station Snotel	4
Sublette	14 NW Pinedale	3.4
Sublette	Daniel Fish Hatchery	3
Sublette	Pocket Creek Snotel	2
Sweetwater	Green River	3
Teton	Grand Targhee Snotel	16
Teton	Jackson Hole-Rendezvous Bowl	15
Teton	Grassy Lake Snotel	12
Teton	Phillips Bench Snotel	12
Teton	Jackson Hole-Raymer	11.5
Teton	Jackson Hole-Mid	10
Teton	Snake River Stn Snotel	8
Teton	Granite Creek Snotel	8
Teton	5 NW Jackson	8
Teton	Base Camp Snotel	8
Teton	2 NE Teton Village	8
Teton	Jackson Hole-Base	7.5
Teton	3 SSW Wilson	7.5
Teton	Moose	7
Teton	Moose	6.5
Teton	Togwotee Pass Snotel	6
Teton	Gros Ventre Summit Snotel	4
Teton	Jackson	4
Teton	Togwotee Mountain Lodge	2
Washakie	Powder River Pass Snotel	2
Yellowstone	Lewis Lake Divide Snotel	12
Yellowstone	Parker Peak Snotel	10
Yellowstone	Thumb Divide Snotel	8
Yellowstone	Two Ocean Plateau Snotel	6
Yellowstone	Old Faithful Ranger Station	6
Yellowstone	Canyon Snotel	6
Yellowstone	Snake River Ranger Station	5
Yellowstone	Sylvan Road Snotel	4
Yellowstone	Sylvan Lake Snotel	4
Yellowstone	Yellowstone East Entrance	1.5

Below is a table summarizing Christmas Day weather extremes.

	Casper (1939-2011)	Lander (1891 - 2011)	Jackson (1916-2011)	Riverton (1907-2011)	Rock Springs (1948-2011)
Highest Temperature (F)	56 (1980)	56 (1899)	47 (1950)	56 (1946)	47 (1980 & 1955)
Lowest Temperature (F)	-15 (2009)	-25 (1891)	-32 (1952)	-33 (1944)	-17 (1987)
Normal High (F)	34	32	28	28	29
Normal Low (F)	13	9	6	4	12
Wettest (in)	0.31 (1988)	0.36 (1943)	1.02 (1955)	0.19 (1949)	0.44 (1968)
Snowiest (in)	5.6 (1988)	5.5 (2007)	13.0 (2008)	4.0 (1949)	3.0 (1968)

Forecasted Christmas High Temperatures

   

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White Christmas Guaranteed

A couple weather systems will assure a White Christmas for all of Western Wyoming.  The first system moving through Saturday night/Sunday morning will drop a few inches of snow, particularly in the mountains. The second and more potent storm will affect the Star Valley area by Monday with potentially an additional several inches of snow.

The Riverton Forecast Office has provided a summary of the expected conditions which can be assessed through this link

http://www.crh.noaa.gov/riw/?n=weatherbriefing

Christmas Holiday Forecast for Western Wyoming

The following link is a Summary of Expected conditions  for the upcoming Holiday Weekend that has been provided by the Riverton Forecast Office.

http://www.crh.noaa.gov/riw/?n=weatherbriefing

At the present time the feed of the forecast for Star Valley is not available. Hopefully it will be fixed soon.

In the meantime here is the latest forecast for the Star Valley area from the Riverton Forecast Office.

STAR VALLEY-
INCLUDING THE CITIES OF...AFTON...ALPINE...THAYNE
223 PM MST THU DEC 20 2012

.TONIGHT...PARTLY CLOUDY. PATCHY FREEZING FOG AFTER MIDNIGHT. LOWS
1 TO 5.
.FRIDAY...PARTLY CLOUDY. HIGHS 29 TO 32.
.FRIDAY NIGHT...PARTLY CLOUDY. LOWS 3 TO 6.
.SATURDAY...PARTLY CLOUDY. HIGHS 32 TO 35.
.SATURDAY NIGHT...NOT AS COLD. MOSTLY CLOUDY. SLIGHT CHANCE OF SNOW
IN THE EVENING...THEN CHANCE OF SNOW AFTER MIDNIGHT. LOWS 19 TO 22.
CHANCE OF SNOW 40 PERCENT.
.SUNDAY...CLOUDY WITH A 50 PERCENT CHANCE OF SNOW. HIGHS NEAR 30.
.SUNDAY NIGHT...MOSTLY CLOUDY WITH A 40 PERCENT CHANCE OF SNOW. LOWS
14 TO 17.
.MONDAY...MOSTLY CLOUDY WITH A 50 PERCENT CHANCE OF SNOW. HIGHS IN
THE MID TO UPPER 20S.
.MONDAY NIGHT...MOSTLY CLOUDY WITH A 40 PERCENT CHANCE OF SNOW. LOWS
13 TO 16.
.CHRISTMAS DAY...MOSTLY CLOUDY IN THE MORNING THEN BECOMING PARTLY
CLOUDY. A 20 PERCENT CHANCE OF SNOW. HIGHS IN THE LOWER TO MID 20S.
.TUESDAY NIGHT...COLDER. PARTLY CLOUDY. LOWS 4 TO 7.
.WEDNESDAY...PARTLY CLOUDY. HIGHS IN THE MID TO UPPER 20S.
.WEDNESDAY NIGHT...PARTLY CLOUDY. LOWS 14 TO 17.
.THURSDAY...MOSTLY CLOUDY WITH A 20 PERCENT CHANCE OF SNOW. HIGHS
NEAR 30.

Summary of December 16-17th Snowfall

Following is the final summary of the snowstorm that affected Western Wyoming issued by the Riverton Forecast Office.

December 16-17th Snowfall

...HEAVY SNOW SUNDAY AND MONDAY ACROSS WESTERN WYOMING...
A WINTER STORM MOVED INTO WESTERN WYOMING SUNDAY AND  MONDAY
PRODUCING SNOWFALL ACROSS THE WEST INTO MONDAY EVENING. THE HEAVIEST
SNOW FELL IN THE SALT AND WYOMING RANGES WHERE AUTOMATED STATIONS
PROVIDED ESTIMATES OF ONE TO TWO FEET. THE TETON RANGE AND SOUTHERN
YELLOWSTONE NATIONAL PARK GENERALLY RECEIVED BETWEEN 12 AND 18 INCHES
OF FRESH SNOW.

Snowfall Totals

County	Station Name	Snowfall
Big Horn	Shell Creek Snotel	3
Big Horn	26 E Lovell	1.5
Big Horn	Otto	0.25
Fremont	Deer Park Snotel	12
Fremont	South Pass Snotel	10
Fremont	Brooks Lake Lodge	9
Fremont	4 ENE South Pass City	9
Fremont	Burroughs Creek Snotel	8
Fremont	Hobbs Park Snotel	7
Fremont	Little Warm Snotel	5
Fremont	St. Lawrence Alt Snotel	5
Fremont	Cold Springs Snotel	5
Fremont	Townsend Creek Snotel	3
Fremont	Castle Creek Snotel	3
Hot Springs	Owl Creek Snotel	2
Johnson	Bear Trap Meadow Snotel	3
Johnson	Cloud Peak Reservoir Snotel	2
Johnson	Hansen Sawmill Snotel	2
Lincoln	Indian Creek Snotel	25
Lincoln	Blind Bull Summit Snotel	23
Lincoln	Commissary Ridge	22
Lincoln	Kelley Ranger Station Snotel	20
Lincoln	Spring Creek Divide Snotel	20
Lincoln	Willow Creek Snotel	19
Lincoln	Blind Bull Summit	17
Lincoln	Hams Fork Snotel	16
Lincoln	Cottonwood Creek Snotel	16
Lincoln	Alpine	15
Lincoln	Salt River Summit Snotel	14
Lincoln	Box Y Ranch	13
Lincoln	2 SE Thayne	12.5
Lincoln	Osmond	12
Lincoln	5 NNE Thayne	11
Lincoln	3 W Afton	10
Lincoln	5 SSE Smoot	9
Lincoln	Fairview	9
Lincoln	Star Valley Ranch	8
Lincoln	Cokeville	7
Lincoln	Cokeville	7
Lincoln	Auburn	6
Lincoln	Kemmerer	4
Lincoln	10 W Kemmerer	3.3
Lincoln	3 SE Bedford	2
Park	Blackwater Snotel	18
Park	Pahaska	10
Park	Younts Peak Snotel	9
Park	Beartooth Lake Snotel	8
Park	Marquette Snotel	8
Park	Kirwin Snotel	8
Park	Evening Star Snotel	6
Park	Timber Creek Snotel	3
Park	2 WSW Cody	3
Park	Wolverine Snotel	3
Park	Cody	3
Park	1 WNW Cody	2.5
Sublette	Triple Peak Snotel	19
Sublette	Loomis Park Snotel	14
Sublette	Snider Basin Snotel	13
Sublette	Bondurant	12
Sublette	Elkhart Park G.S. Snotel	12
Sublette	Kendall Ranger Station Snotel	10
Sublette	Pocket Creek Snotel	10
Sublette	Big Sandy Opening Snotel	10
Sublette	Larsen Creek Snotel	10
Sublette	Gunsite Pass Snotel	9
Sublette	East Rim Divide Snotel	9
Sublette	New Fork Lake Snotel	7
Sublette	1 N Pinedale	6
Sublette	Daniel Fish Hatchery	6
Sublette	Pinedale	5
Sublette	Cora	5
Sublette	2 SE Daniel	4
Sublette	Snider Basin	4
Sublette	14 NW Pinedale	3.8
Sublette	Marbleton	3
Sweetwater	Buckboard Marina	2
Sweetwater	Green River	1
Sweetwater	Green River	1
Sweetwater	1 E Rock Springs	1
Sweetwater	Rock Springs	0.5
Teton	Jackson Hole-Raymer	18
Teton	Phillips Bench Snotel	17
Teton	Granite Creek Snotel	16
Teton	Grassy Lake Snotel	14
Teton	Jackson Hole-Mid	14
Teton	3 SSW Wilson	13.5
Teton	Base Camp Snotel	13
Teton	Grand Targhee Ski Area	13
Teton	Grand Targhee-Chief Joseph	13
Teton	Jackson Hole-Rendezvous Bowl	13
Teton	Jackson Lake	12
Teton	Gros Ventre Summit Snotel	11
Teton	Togwotee Pass Snotel	10
Teton	Snake River Stn Snotel	10
Teton	5 WNW Moran	10
Teton	Grand Targhee Snotel	8
Teton	2 NW Jackson	8
Teton	Rafter J Ranch	8
Teton	Jackson	8
Teton	5 NW Jackson	8
Teton	2 NE Teton Village	7
Teton	Moose	7
Teton	Snow King Ski Area	6
Teton	Jackson Hole-Base	6
Teton	8 E Moran	5
Teton	4 SSW Jackson	4.6
Teton	Togwotee Mountain Lodge	4
Teton	12 NE Jackson	4
Washakie	Powder River Pass Snotel	3
Yellowstone	Lewis Lake Divide Snotel	20
Yellowstone	Thumb Divide Snotel	13
Yellowstone	Two Ocean Plateau Snotel	13
Yellowstone	Sylvan Lake Snotel	9
Yellowstone	Sylvan Road Snotel	7
Yellowstone	Canyon Snotel	5
Yellowstone	Parker Peak Snotel	4