Daily Winter Weather Report
Date: Monday - 19 December 2011
|Station||Max Temp||Min Temp||Pres Temp||New Snow||Depth||Sky||Present Conditions|
|Road Section||Status||Conditions||Public Access / Info|
|Gardiner to Mammoth||YR||Good||STA|
|Mammoth to Tower||YR||Good||STA|
|Tower to NE Entrance||YR||Good||STA|
|Beartooth Highway||CLOSED *||CLOSED *||CLOSED *|
|Canyon to Lake||CLOSED||CLOSED||CLOSED|
|Firehole Canyon Drive||CLOSED||CLOSED||CLOSED|
|Grant to South Entrance||Open||Rubber tracked oversnow concession vehicles|
|Junction to Chief Joseph Hwy||CLOSED *||CLOSED *||CLOSED *|
|Lake to East Entrance||CLOSED||CLOSED||CLOSED|
|Lake to West Thumb||CLOSED||CLOSED||CLOSED|
|Madison to Old Faithful||Open||Rubber tracked oversnow concession vehicles|
|Madison to West Yellowstone||Open||Rubber tracked oversnow concession vehicles|
|Mammoth to Norris||Open||Rubber tracked oversnow concession vehicles|
|Norris to Canyon||Open||Rubber tracked oversnow concession vehicles|
|Norris to Madison||Open||Rubber tracked oversnow concession vehicles|
|Old Faithful to Grant||Open||Rubber tracked oversnow concession vehicles|
|Tower to Canyon||CLOSED *||CLOSED *||CLOSED *|
YR=Year Round / NR=No Restrictions / STA=Snow Tires Advised / STR=Snow Tires Required
* NOTE: CLOSED FOR THE SEASON.
# Poor road conditions - bare spots and melting snow - Restricted to Snowcoaches Only.
The park service plowing schedule for roads for the spring season.
******** FOR CURRENT ROAD INFORMATION PLEASE CALL 307-344-2117 ********
No travel is allowed past Canyon VC, so the rim drives are not open to the public at this time.
East Entrance road is closed to wheeled vehicles.
Dangerous avalanche conditions may already exist in many back country areas, please call the Recorded Avalanche Advisory 406-587-6981 for the most current conditions.
Caution advised for snow falling off of building roofs. Park accordingly.
* * Be prepared for bitter cold (sub-zero) temperatures. See NWS Weather Forecast below for detailed information. * *
by the National Weather Service Riverton, WY
Today: Mostly sunny, with a high near 24°F and a low around 0°F. Wind chill values as low as -10°F.
Tuesday: A 20 percent chance of snow after 11am. Mostly sunny, with a high near 25°F and a low around 8°F. Wind chill values as low as -15°F. New night time snow accumulation of less than one inch possible.
Wednesday: Snow likely. Cloudy, with a high near 19°F and a low around -6°F. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible.
Thursday: Mostly sunny, with a high near 14°F and a low around -9°F.
Friday: Mostly sunny, with a high near 18°F and a low around 0°F.
Saturday and Sunday: A chance of snow. Partly sunny, with a high near 20°F and a low around 0°F.
|* * * Snow Depth Totals as reported at SNOTELs * * *|
|Station||Depth (inches)||Station||Depth (inches)|
|Black Bear||34||Parker Peak||32|
|Blackwater||36||Snake River Station||20|
|Evening Star||33||Sylvan Road||17|
|Fisher Creek||40||Thumb Divide||19|
|Grassy Lake||26||Two Ocean Plateau||41|
|Lewis Lake Divide||27||West Yellowstone||14|
|Madison Plateau||23||Whiskey Creek||19|
from the Gallatin National Forest Avalanche Center - December 19, 2011 - this report is by Eric Knoff. This advisory does not apply to operating ski areas.
Over the past 12 hours a fast moving cold front has swept down from the north, depositing 2 to 3 inches of snow in the mountains around Bozeman and Big Sky. The southern ranges only picked up a trace. Winds spiked during the frontal passage, but have decreased to 5-15 mph out of the North-northwest. Mountain temperatures are currently in the high teens to low 20s Fahrenheit. Snow showers will taper off this morning and skies will become partly cloudy by this afternoon. Today, mountain temperatures will rise into the high 20s Fahrenheit and winds will blow out of North-northwest at 10-20 mph.
Snowpack and Avalanche Discussion:
The Bridger and Madison Ranges, the southern Gallatin Range and the Lionhead area near West Yellowstone:
Avalanche forecasters commonly track well developed weak layers such as surface hoar, depth hoar and near surface facets. By mapping the distribution of a weak layer, many times it becomes possible to determine what areas may be unstable. This year is different.
Our snowpack in many areas is essentially one big weak layer. At this point, our primary avalanche concern is areas where well developed slabs are present. If a slab does exist it will likely be resting over non-cohesive, sugary facets - a prime structure for creating avalanches. This weak structure has produced avalanches for local ski patrols doing control work over the past few days.
Yesterday, Doug toured into Beehive Basin looking for a small skier triggered slide which occurred on Friday. He did not locate the slide, but managed to find plenty of weak snow.
On slopes where the snowpack is more than two feet deep, mainly wind loaded slopes, human triggered avalanches are possible and the Avalanche Danger is rated MODERATE. On slopes with less than two feet of snow the Avalanche Danger is rated LOW.
The northern Gallatin Range and mountains around Cooke City:
Mark and I spent the past two days in Cooke City looking/digging for weak snow. We felt like two miners trying to strike it rich. After hours of shoveling and multiple stability tests we concluded our efforts were not going to be rewarded monetarily.
However, our work did pay off and we left feeling satisfied and confident the snowpack is gaining strength. We did occasionally find weak snow willing to react in stability tests, but we concluded it would take a large load or finding a steep slope with an uncharacteristically shallow snowpack to trigger an avalanche.
A similar but slightly weaker snowpack exists in the northern Gallatin Range. Although it's still possible to find weak snow near the ground, recent observations are indicating the pack in this area is also gaining strength. In order to trigger a slide on deeper layers it would require a skier or rider finding the sweet spot. This would most likely be in steep upper elevation terrain where the snowpack is shallow, specifically near rock bands or below ridglines.
While weak snow near the ground is our primary avalanche concern, near surface instabilities such as surface hoar and near surface facets are now buried by a few inches on new snow. This combination could produce small slab avalanches or fast moving sluffs capable of catching a skier or rider off guard
Today, heightened avalanche conditions exist on slopes steeper than 35 degrees where the Avalanche Danger is rated MODERATE. All other slopes have a LOW Avalanche Danger.
The next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations, drop us a line at firstname.lastname@example.org or call us at: 406-587-6984.
PHOTOS, SNOWPITS, and VIDEOS
If you have any snowpack or avalanche observations, drop them a line at email@example.com or call: 406-587-6984.
For detailed Avalanche Terms utilized here, please see the Avalanche Glossary.
Information provided by Yellowstone National Park, National Weather Service and Gallatin National Forest Avalanche Center
|I n d e x|
|Adult Programs||Entrances||Old Faithful Live WebCam||Visitor Stats|
|Amphibians||Entrance Fees||Pets||Volcano Observatory|
|Animals||Fall Closure||Phone Numbers||Waterfalls|
|Bear Management||Fishing Fees||Ranger Led Activities||WebCams|
|Bear Sightings||Fishing Regulations||Reptiles||Wildflowers|
|Biking||Getting Here||Reunions||Winter Closing|
|Boating||Hiking||Rivers, Creeks & Streams||Winter Opening|
|Books||History||Roads||Winter Weather Reports|
|Butterflies||Junior Ranger Program||Schedule||Wolf Project|
|Camping||Lakes||Search Page||Wolf Sightings|
|Campground Maps||Location||Spring Opening||Wolverine Help|
|Challenges||Lodging||Star Talks||Yellowstone ~ the Name|
|Chat Page||Lynx Help||Trip Planner pdf||Young Scientist|
|Clinics / Medical||Mammal List||Trip Reports||Youth Conservation Corps|
|Yellowstone National Park WebCams|
|Old Faithful Live||All Old Faithful||Old Faithful Static||Old Faithful VC||North Entrance||Mt Washburn||Mammoth||YVO WebCam|
|Rexburg Idaho WebCams|
|♦ Rexburg, Idaho WebCams ♦|
|Yellowstone Area Highway WebCams|
|Alpine Junction Hwy 89 (South)||Monida Pass I-15 (North)|
|Bozeman Pass I-90 (North)||Osborne Bridge Hwy 20 (West)|
|Henry's Lake North Hwy 20 (West)||Raynolds Pass MT 87 (North or West)|
|Henry's Lake South Hwy 20 (West)||Teton Pass WY 22 (South)|
|State Road Reports|
|Gardiner, Montana||Silver Gate, Montana||West Yellowstone, Montana||Cooke City, Montana|
|Livingston, Montana||Cody, Wyoming||Jackson Hole, Wyoming||Yellowstone National Park|
|The Great Outdoors Net||Great Outdoor Recreational Places|
|Gardiner, Montana||World Humanity|
by John William Uhler
Back to: Yellowstone Up Close and Personal