Sunday, April 30, 2017

Wet Winter Review

Cliff Mass has blogged on the unusually wet winter it has been across much of the Western U.S. Of interest is the large portion of Western Wyoming that had a near record wet winter.



Saturday, April 29, 2017

A Spatial View of a Wet Winter

This has been an amazingly wet winter-- but where has it been most unusual?   To gain insights into this important question, here is an analysis from the Western Regional Climate Center (WRCC) showing the percent of normal for October 2016-March 2017 precipitation over the western U.S.  The darkest greens indicate the wettest on record.  A huge region region stretching from northern CA through northern Nevada, into Idaho,  Wyoming, Montana and eastern WA.  Nearly the entire Northwest U.S. was in top 10% wet season.  The April version will add parts of western WA.


The late winter (Feb-March) maps shows how wet conditions were particularly unusual in the northern Rockies.  Eastern Washington, Idaho, and western Montana had unprecedented large amounts of precipitation.

Mean temperatures from October through March?  Cooler than normal over Washington and Oregon....no big surprise.


This week, a colleague at the US Army Corps of Engineers told me that the soils of our region are extraordinarily saturated....and that he was worried about spring flooding.   Well, here is the latest soil moisture observations based on the GRACE satellite (measures moisture using its effects of gravity). The entire Northwest is WAY wetter than normal (darker blue colors).

Spring Storm Summary for April 26th - 28th 2017


  Overview
A vigorous spring storm impacted the Cowboy State Wednesday, April 26th through Friday, April 28th.  Western Wyoming saw the heaviest snowfall late Wednesday night into Thursday morning when mountain locations were picking up 1 to 2" an hour.  Western valleys were mainly rain Wednesday and Wednesday evening, before changing to snow during the predawn hours Thursday morning. This storm system then began to gradually impact areas east of the Divide Thursday with precipitation becoming widespread Thursday afternoon and evening. Precipitation in the lower elevations east of the Divide changed to mainly snow Thursday afternoon into Thursday night. The main exception was below 5000 feet in the Big Horn Basin where the precipitation was mainly rain through the entire event.  Accumulating snow varied considerably by elevation with a few hundred feet making the difference between little or no snow to several inches or more of snow depth.
The heaviest accumulating snow east of the Divide occurred across the eastern slopes of the Bighorn Mountains and adjacent foothills including the Buffalo area, as well as Lander Foothills and eastern slopes of the Wind River Mountains.  A few roads were closed during this event.  The highway through the Wind River Canyon was closed for about 24 hours Friday into Friday night due to large boulders falling onto the highway.
Large drifts (3 to 4 feet deep) near Buffalo
 Wind River Canyon 

Snow
Location                              Snowfall
Lincoln County...
 Commissary Ridge...                 21 inches.
 Blind Bull Summit...                15 inches.
 Cottonwood Creek Snotel...          10 inches.
 Willow Creek Snotel...               9 inches.
 Blind Bull Summit Snotel...          9 inches.
 Star Valley Ranch...        6.5 to 8.5 inches.
 Indian Creek Snotel...               8 inches.
 Box Y Ranch...                       7 inches.
 Spring Creek Divide Snotel...        7 inches.
 2 SE Thayne...                     5.3 inches.
 Hams Fork Snotel...                  4 inches.
 Kelley Ranger Station Snotel...      4 inches.
 5 SSE Smoot...                       3 inches.
 Afton...                           1.9 inches.
 Fossil Butte...                    1.7 inches.
 3 N Etna...                        1.5 inches.
 Salt River Summit Snotel...          1 inch.
Big Horn County... Powder River Pass... 9 inches. Bald Mountain Snotel... 9 inches. Bone Springs Divide Snotel... 6 inches. Shell Creek Snotel... 3 inches. Fremont County... Townsend Creek Snotel... 33 inches. Hobbs Park Snotel... 31 inches. South Pass Snotel... 29 inches. Deer Park Snotel... 29 inches. Atlantic City... 24.5 inches. St. Lawrence Alt Snotel... 20 inches. 9.5 SW Lander... 19 inches. Sinks Canyon... 17 inches. Sweetwater Station... 16.3 inches. Cold Springs Snotel... 16 inches. 9 SSE Lander... 15 inches. 6 SW Lander... 14.8 inches. 9 S Lander... 14.6 inches. 7 SE Lander... 12 inches. 7 WNW Lander... 10.9 inches. Riverton Airport... 9.9 inches. Brooks Lake... 9 inches. Jeffrey City... 8 inches. Lander Airport... 7.7 inches. 3 SW Lander... 7.5 inches. 4 W Riverton... 7 inches. Little Warm Snotel... 6 inches. Lander town... 2 to 6 inches. Sweetwater Station... 5 inches. Burroughs Creek Snotel... 5 inches. Riverton... 4.8 inches. Hudson... 4.5 inches. Dubois... 3 inches. 4 WSW Lander... 3 inches. 2 W Riverton... 2 inches. 9 NW Riverton... 2 inches. Burris... 0.4 inches. Hot Springs County... Owl Creek Snotel... 10 inches. 9 NE Thermopolis... 0.3 inches. Johnson County... Little Goose Snotel... 20 inches. Soldier Park Snotel... 19 inches. Cloud Peak Reservoir Snotel... 17 inches. Hansen Sawmill Snotel... 16 inches. 4 SSW Buffalo... 13 inches. 17 NNW Kaycee... 12.5 inches. 13 SSE Buffalo... 12 inches. Buffalo... 8.2 inches. Bear Trap Meadow Snotel... 8 inches. 16 NNW Kaycee... 8 inches. 17 E Kaycee... 7.7 inches. 7 NE Buffalo... 5 inches. 16 SE Buffalo... 3.5 inches. Natrona County... Casper Mountain Snotel... 14 inches. Grave Spring Snotel... 9 inches. 5 SSW Casper... 7 inches. Casper Mountain... 7 inches. Reno Hill Snotel... 6 inches. 1 SW Casper... 6 inches. 10 WSW Casper... 5 inches. 1 S Casper... 3.8 inches. 4 SW Casper... 3.2 inches. 3 WSW Casper... 3 inches. Midwest... 3 inches. Casper Airport... 2.5 inches. 2 S Casper... 2 inches. 12 NE Lysite... 1 inch. Casper... 0.5 to 1 inch. Park County... Marquette Snotel... 25 inches. Kirwin Snotel... 19 inches. Timber Creek Snotel... 16 inches. Blackwater Snotel... 12 inches. 3 NE Sunshine... 11.2 inches. Evening Star Snotel... 6 inches. Beartooth Lake Snotel... 5 inches. 26 SW Cody... 4 inches. 5 ESE Cody... 3.5 inches. Younts Peak Snotel... 3 inches. Wolverine Snotel... 3 inches. Pahaska... 2.2 inches. 1 ENE Wapiti... 2 inches. 4 SE Cody... 0.2 inches. Sublette County... Triple Peak Snotel... 8 inches. Loomis Park Snotel... 6 inches. Gunsite Pass Snotel... 6 inches. New Fork Lake Snotel... 4 inches. Pinedale... 2.3 inches. Elkhart Park G.S. Snotel... 2 inches. East Rim Divide Snotel... 2 inches. Daniel Fish Hatchery... 1.5 inches. 14 NW Pinedale... 1.5 inches. Larsen Creek Snotel... 1 inch. Kendall Ranger Station Snotel... 1 inch. Big Sandy Opening Snotel... 1 inch. Sweetwater County... Bairoil... 10.5 inches. Green River... 1 to 2 inches. 7 SE Rock Springs... 2.7 inches. Wamsutter... 1 to 2 inches. 5 N Farson... 0.5 inches. Teton County... Grand Targhee Snotel... 29 inches. Jackson Hole - Raymer... 23 inches. Jackson Hole - Rendezvous Bowl... 21 inches. Grassy Lake Snotel... 19 inches. Jackson Hole - Mid Mountain... 18 inches. Togwotee Mountain Lodge... 12 inches. 1 NNW Alta... 11 inches. Moose... 11 inches. Phillips Bench Snotel... 11 inches. Togwotee Pass Snotel... 11 inches. Jackson Hole - Base... 8 inches. Snake River Stn Snotel... 8 inches. Gros Ventre Summit Snotel... 7 inches. 2 NE Teton Village... 7 inches. Granite Creek Snotel... 5 inches. Base Camp Snotel... 4 inches. Darwin Ranch... 3.9 inches. Jackson Dam... 3.2 inches. Jackson... 1.4 inches. Washakie County... Powder River Pass Snotel... 10 inches. Middle Powder Snotel... 6 inches. 27 S Ten Sleep... 1 inch. Yellowstone National Park... Parker Peak Snotel... 10 inches. Sylvan Lake Snotel... 9 inches. Thumb Divide Snotel... 8 inches. Canyon Snotel... 6 inches. Lewis Lake Divide Snotel... 5 inches. Sylvan Road Snotel... 2 inches. Tower Falls Ranger Station... 1.2 inches.

Friday, April 28, 2017

Preliminary Snowfall Totals for Wednesday through Friday morning


Public Information Statement
National Weather Service Riverton WY
220 PM MST Fri Apr 28 2017

...Preliminary Snowfall Totals for Wednesday through Friday
morning...

A late spring storm system continues to bring snow to much of
Wyoming East of the Divide today. Below are snowfall totals from
various sources through this morning. More snow is expected
through early Saturday morning.

Snotel data were through 7 AM Friday morning. SnoTELs (Snow
Telemetry) are remote sensing sites in high mountain watersheds.
Snowfall data from SNOTELS are estimated based on snow water
equivalent.

Location                              Snowfall
Lincoln County...
 Commissary Ridge...                 21 inches.
 Blind Bull Summit...                15 inches.
 Cottonwood Creek Snotel...          10 inches.
 Blind Bull Summit Snotel...          9 inches.
 Willow Creek Snotel...               9 inches.
 Indian Creek Snotel...               8 inches.
 Spring Creek Divide Snotel...        7 inches.
 Box Y Ranch...                       7 inches.
 Star Valley Ranch...                 7 inches.
 2 SE Thayne...                     4.8 inches.
 Hams Fork Snotel...                  4 inches.
 Kelley Ranger Station Snotel...      4 inches.
 5 SSE Smoot...                       3 inches.
 Afton...                           1.9 inches.
 3 N Etna...                        1.5 inches.
 Salt River Summit Snotel...          1 inch.
Big Horn County... Powder River Pass... 9 inches. Bald Mountain Snotel... 5 inches. Bone Springs Divide Snotel... 5 inches. Shell Creek Snotel... 3 inches. Fremont County... Atlantic City... 14.5 inches. Townsend Creek Snotel... 14 inches. South Pass Snotel... 11 inches. 7 SE Lander... 10 inches. Brooks Lake... 9 inches. Deer Park Snotel... 9 inches. 26 SSE Riverton... 8 inches. Hobbs Park Snotel... 8 inches. 6 SW Lander... 7.6 inches. 3 SW Lander... 7.5 inches. Riverton Airport... 6.9 inches. 9 S Lander... 5.8 inches. Lander Airport... 5.1 inches. Little Warm Snotel... 5 inches. Sweetwater Station... 5 inches. Burroughs Creek Snotel... 5 inches. 7 WNW Lander... 3.7 inches. Lander... 3.3 inches. Cold Springs Snotel... 3 inches. St. Lawrence Alt Snotel... 3 inches. 9 NW Riverton... 2 inches. Dubois... 2 inches. 2 W Riverton... 2 inches. Riverton... 1.8 inches. Hot Springs County... Owl Creek Snotel... 1 inch. Johnson County... Soldier Park Snotel... 16 inches. Little Goose Snotel... 15 inches. Hansen Sawmill Snotel... 11 inches. 4 SSW Buffalo... 10 inches. Buffalo... 6.2 inches. Bear Trap Meadow Snotel... 5 inches. 17 NNW Kaycee... 4.5 inches. 17 E Kaycee... 3.6 inches. Natrona County... Casper Mountain Snotel... 9 inches. Grave Spring Snotel... 6 inches. Reno Hill Snotel... 5 inches. Casper Mountain... 4 inches. 5 SSW Casper... 4 inches. 3 WSW Casper... 2.4 inches. Casper Airport... 2.3 inches. 10 WSW Casper... 2 inches. 1 S Casper... 2 inches. Casper... 1 inch. Park County... Marquette Snotel... 20 inches. Blackwater Snotel... 12 inches. Kirwin Snotel... 12 inches. Timber Creek Snotel... 10 inches. Beartooth Lake Snotel... 5 inches. Evening Star Snotel... 5 inches. 3 NE Sunshine... 4.3 inches. Wolverine Snotel... 3 inches. Younts Peak Snotel... 3 inches. Pahaska... 2.2 inches. 1 ENE Wapiti... 2 inches. 5 ESE Cody... 0.7 inches. 4 SE Cody... 0.2 inches. Sublette County... Triple Peak Snotel... 8 inches. Gunsite Pass Snotel... 6 inches. Loomis Park Snotel... 6 inches. New Fork Lake Snotel... 4 inches. Pinedale... 2.3 inches. East Rim Divide Snotel... 2 inches. Elkhart Park G.S. Snotel... 2 inches. Daniel Fish Hatchery... 1.5 inches. 14 NW Pinedale... 1.5 inches. Larsen Creek Snotel... 1 inch. Big Sandy Opening Snotel... 1 inch. Kendall Ranger Station Snotel... 1 inch. Sweetwater County... Bairoil... 10.5 inches. 7 SE Rock Springs... 2 inches. Wamsutter... 1 inch. 5 N Farson... 0.5 inches. Teton County... Grand Targhee Snotel... 29 inches. Jackson Hole - Raymer... 23 inches. Jackson Hole - Rendezvous Bowl... 21 inches. Grassy Lake Snotel... 19 inches. Jackson Hole - Mid Mountain... 18 inches. Togwotee Mountain Lodge... 12 inches. Togwotee Pass Snotel... 11 inches. Phillips Bench Snotel... 11 inches. 1 NNW Alta... 11 inches. Moose... 11 inches. Snake River Stn Snotel... 8 inches. Jackson Hole - Base... 8 inches. 2 NE Teton Village... 7 inches. Gros Ventre Summit Snotel... 7 inches. Granite Creek Snotel... 5 inches. Base Camp Snotel... 4 inches. Darwin Ranch... 3.3 inches. Jackson Dam... 3.2 inches. Jackson... 1.4 inches. Washakie County... Powder River Pass Snotel... 7 inches. Middle Powder Snotel... 3 inches. 27 S Ten Sleep... 1 inch. Yellowstone National Park... Parker Peak Snotel... 10 inches. Sylvan Lake Snotel... 9 inches. Thumb Divide Snotel... 8 inches. Canyon Snotel... 6 inches. Lewis Lake Divide Snotel... 5 inches. Sylvan Road Snotel... 2 inches. Tower Falls Ranger Station... 1.2 inches.

Winter 2016/17 Snowfall at Star Valley Ranch Reaches 20 Feet

New snow overnight of 4 inches at Star Valley Ranch


With the 4 inches of snow that fell overnight the Winter Season of 2016/17 has seen 20 feet of snow in Star Valley Ranch.  Not only has there been well above normal snowfall the amount of precipitation rain/melted snow has truly been impressive. The measurements are taken in our backyard on Vista Dr. in Star Valley Ranch at 6400 feet.

Following is the month by month breakdown of both since last September


Month          Snowfall    Precipitation

September           .5                3.45

October              9.8                6.05

November        17.5                1.63

December         64.0                3.90

January             69.5                5.00

February            41.1               5.04

March                17.2                2.81

April(thus far)    22.2               4.36

Totals                241.8             32.24  

The greatest snow depth was 41 inches on February 8 2017    

Thursday, April 27, 2017

Snow To Continue Across Much of Wyoming Today

Two inches on the ground at Star Valley Ranch this morning



URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
514 AM MDT Thu Apr 27 2017

...SIGNIFICANT SNOW OVER THE WEST ENDING THIS MORNING, BUT
SHIFTING TO NORTHERN AND CENTRAL WYOMING TODAY AND TONIGHT, AND
LASTING THROUGH FRIDAY EVENING...

.A cold spring storm will impact the Cowboy State through Friday
night with significant snowfall. The main impacts from this storm
system will shift from western Wyoming this morning, into
northern and central Wyoming later today and this evening as the
rain and snow changes to all snow, and becomes heavy at times. The
snow is gradually expected to taper off from north to south
Friday afternoon into Friday night.


Jackson Hole-Star Valley-
Including the cities of Jackson, Afton, Alpine,
Star Valley Ranch, and Thayne
514 AM MDT Thu Apr 27 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL NOON MDT
TODAY...

* TIMING...Periods of snow today with the heaviest snow expected
  through about 9 AM. Star Valley could still see some rain early
  this morning, but any rain should change quickly to snow this
  morning.

* TOTAL SNOW...1 to 4 inches.

* MAIN IMPACT...Highways will be mainly wet across Star Valley,
  but vary from wet to slick or slushy in spots across Jackson
  Hole especially from Moose northward. Mountain Pass will be
  slick and hazardous with very low visibility at times.

Model Forecast Snowfall from 6am- midnight Thursday April 27 2017


Wednesday, April 26, 2017

Snow Returns to Much of Wyoming

Model Total Snow Forecast Through midnight Friday


URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
257 PM MDT Wed Apr 26 2017

...MORE SNOW RETURNING TO WESTERN AND CENTRAL WYOMING THROUGH
FRIDAY NIGHT...

.A low pressure storm system moving across the Pacific northwest
will spread increasing snow into the west tonight and Thursday.
Through Thursday the snow will spread east of the Continental
Divide across the north. The storm system will then strengthen
and close off over south central to southeast Wyoming Thursday
night with potential heavy convective snow developing over the
Big Horn mountains, Johnson, Fremont and Natrona counties.

The mountains may see 10 to 20 inches of snow with 5 to 10 inches
in the lower elevations with local 12 to 15 inch amounts possible
in the foothills areas around Buffalo, Casper and Lander. The
storm system will dig south across northern Colorado and
eventually into northern New Mexico by Saturday when the storm
will be too far south for major impacts in Wyoming.


Jackson Hole-Star Valley-
Including the cities of Jackson, Afton, Alpine,
Star Valley Ranch, and Thayne
257 PM MDT Wed Apr 26 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS
EVENING TO NOON MDT THURSDAY...

* TIMING...A mix of rain and snow will change to snow tonight
  and continue into Thursday.

* TOTAL SNOW...3 to 8 inches.

* MAIN IMPACT...Highways will become slick, slushy or snow
  covered.

Winter Weather Advisory Wednesday Night and Thursday Much of Western Wyoming

Model Total Snow Forecast Through Thursday Afternoon


URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
205 AM MDT Wed Apr 26 2017

...MORE SNOW RETURNING TO WESTERN WYOMING...

.After a lull in the snow this morning, another approaching
Pacific cold front will bring more snow from this afternoon into
Thursday.


Jackson Hole-Star Valley-
Including the cities of Jackson, Afton, Alpine,
Star Valley Ranch, and Thayne
205 AM MDT Wed Apr 26 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS
EVENING TO NOON MDT THURSDAY...

* TIMING...A mix of rain and snow will change to snow tonight and
  continue into Thursday.

* TOTAL SNOW...2 to 5 inches.

* MAIN IMPACT...Highways will become slick, slushy or snow
  covered.

.............................................

Salt River and Wyoming Ranges-
205 AM MDT Wed Apr 26 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO
NOON MDT THURSDAY...

* TIMING...Snow showers will become steadier and heavier this
  afternoon and continue into Thursday. The heaviest snow is
  expected later tonight and Thursday morning.

* TOTAL SNOWFALL...5 to 9 inches.

* MAIN IMPACT...Highways will become slick, slushy or snow
  covered, including Salt Pass. Visibility could be reduced to
  under one half mile at times.