Monday, December 31, 2012

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

Sunday, December 30, 2012

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

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.

Saturday, December 29, 2012

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 

                        

Tuesday, December 25, 2012

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
Probability of a White Christmas
Locations Covered by
Snow Prior to Monday
Locations as of 12/21 where snow cover was present across Wyoming.








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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Saturday, December 22, 2012

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

Thursday, December 20, 2012

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.

Wednesday, December 19, 2012

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