Turnagain Pass

Good morning backcountry travelers this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Saturday, November 28 at 7 am. This will serve as a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (advisory does not apply to highways, railroads, or operating ski areas).

ANNOUNCEMENTS

Turnagain Pass snowmachine area is open to motorized use. All CNFAIC Staff areas including Johnson Pass, Placer, Twenty-Mile, and all areas on the Seward Ranger District will remain closed until there is more snow. The Turnagain Pass open riding area is on the west side of the highway from Bertha Creek Campground north to the Forest boundary near the Turnagain Arm.

ATTENTION SNOWMACHINERS!!!

Avalanche danger may exist at any time in backcountry areas like Turnagain Pass on the Chugach National Forest, whether these areas are open or closed. The US Forest Service does not close areas due to avalanche danger. When areas designated for use by snowmachines on the Chugach National Forest are closed, a primary reason is for the protection of natural resources in accordance with the current Forest Plan. Similarly, on open sign does not mean that it is safe. There are many inherent dangers associated with traveling in the backcountry including avalanches. Safe backcountry travel requires training and experience. You Control Your Own Risk by choosing where, when and how to travel. The Chugach National Forest Avalanche Information Center provides pertinent information to assist you in making your own decisions for traveling in these backcountry areas.

Opening of these motorized areas in the early season can be subject to immediate closure based on sufficient snow to prevent the tracks of a snowmachine from tearing up vegetation. If the weather changes and the snowpack gets too thin to prevent resource damage, then areas may be closed again. It is your responsibility to check the official open/closed status of these areas with the Chugach National Forest. CNFAIC Staff resources for information regarding these motorized areas can be found through the Glacier Ranger District, and/or the Chugach National Forest Avalanche Information Center.

WEATHER ROUNDUP

What a crazy end to November. AnCNFAIC Staff 2 feet of snow has fallen in the last 24 hours in many areas covered by this advisory. Most of that fell yesterday. 4 to 6 inches fell last night. 2 to 3 inches of water equivalent fell in this storm. Snowfall totals for the two day storm range from 1 to 2 feet at sea level and 3 to 4 feet above 500 ft.

The snows have currently stopped. Expect less significant snow today. The next 966 mb low will move into the area tonight providing more snow tomorrow. The radar and satellite images support this NWS forecast.

The Center Ridge weather station in Turnagain Pass (1800 ft) is reporting 27 deg F (down 3 deg), 1.6 inches of water equivalent and 20 inches of snow. Once again this snow amount is my best interpretation of the station data.

The Sunburst weather station in Turnagain Pass (3800 ft) is reporting 19 deg F (down 4 deg), and winds averaging 22 and gusting 30-35 mph out of the east.

A cool off is present throughout the area. Temps are down 3-5 degrees from yesterday. Winds are just starting to pick up again this morning.

AKZ125-260100-

WESTERN PRINCE WILLIAM SOUND-

INCLUDING…WHITTIER…SEWARD…GIRDWOOD…MOOSE PASS

500 AM AKST SAT NOV 28 2009

…STRONG WIND TONIGHT AND SATURDAY NEAR SEWARD AND WHITTIER…

.TODAY…SNOW SHOWERS…POSSIBLY MIXED WITH RAIN THIS AFTERNOON ALONG

THE COAST. LOCAL AREAS OF BLOWING SNOW. SNOW ACCUMULATIONS 1 TO 4

INCHES. HIGHS IN THE 30S. NORTH TO EAST WINDS 10 TO 25 MPH. GUSTS TO

35 MPH NEAR SEWARD.

.TONIGHT…CLOUDY WITH SCATTERED SNOW SHOWERS. LOWS IN THE MID

TEENS TO LOWER 30S. NEAR SEWARD AND WHITTIER…NORTH TO WEST WINDS 15

TO 25 MPH WITH GUSTS 35 TO 45 MPH. ELSEWHERE…NORTH TO WEST WINDS 5

TO 15 MPH.

.SUNDAY…MOSTLY CLOUDY. SCATTERED SNOW SHOWERS. HIGHS IN THE LOWER

20S TO LOWER 30S. NEAR SEWARD AND WHITTIER…NORTH TO WEST WINDS 15

TO 25 MPH. GUSTS 35 TO 45 MPH IN THE MORNING. ELSEWHERE…NORTH TO

WEST WINDS 5 TO 15 MPH.

.SUNDAY NIGHT…MOSTLY CLOUDY WITH SCATTERED SNOW SHOWERS. LOWS

5 TO 10 ABOVE. VARIABLE WIND TO 10 MPH. NEAR WHITTIER…WEST WIND 15

MPH BECOMING VARIABLE AFTER MIDNIGHT.

TEMPERATURE / PRECIPITATION

SEWARD 37 21 26 / 80 60 30

GIRDWOOD 33 20 25 / 30 30 20

An educational opportunity is coming up to learn more about mountain weather, Dec 5th. Weather for the Backcountry Traveler Lecture Series. Given by AK Avalanche School and the NWS 9am-5pm visit www.alaskaavalanche.com for more info.

AVALANCHE DISCUSSION

For those of you out yesterday you saw the craziness. Widespread collapsing snowpacks. If the collapse was near a steep slope an avalanche resulted. Widespread natural avalanche activity yesterday from Girdwood to Seward. Lots of avalanche activity reported in the Summit Lake area. A large natural avalanche buried the Seward Highway 21 miles north of Seward. No surprise that we saw this much activity yesterday with that much new snow and weight added to the snowpack in a 48 hour time period. All that weight and 4 plus feet of snow is resting on the very week faceted snow that fell and formed earlier this month.

The cooler temperature and the subsiding snowfall will reduce the avalanche hazard slightly today. However, the uncertainty and the increasing winds will keep us at a CONSIDERABLE hazard rating. Dangerous avalanche conditions still exist today. Careful snowpack evaluation, cautious routefinding and conservative decision-making will be essential. Natural avalanches possible; human-triggered avalanches likely today.

We know we have week snow under our current snowpack. I would play it safe again today and give the snowpack time to adjust. These types of storms are what put the Kenai and Chugach Ranges on the map. Large heavy wet storms that hammer the steep terrain we all love. This snow will likely settle and paste itself in tight. Most importantly we have to remember what this storm is setting on. The week faceted crystals at the ground will compress and metamorphose over time. We just need to give them time!

If you have observations for us send them using the observations button on the advisory page of our website. This concludes today’s advisory. The next advisory will be Sunday, November 29th. Have a great day.