Good morning backcountry travelers this is Matt Murphy with the Chugach National Forest Avalanche Information Center on Saturday, November 20th at 7am. This will serve as a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (this advisory does not apply to highways, railroads, or operating ski areas).
All areas designated for snowmachines on Chugach National Forest lands are still closed. We are measuring the snow in these areas daily and will open them as soon as there is enough snow to protect the ground and vegetation from being torn up by the tracks of a snowmachine. Thanks for your patience.
-TEMPS: There is still a temperature inversion this morning; so, temps are colder down low at sea level than up high on the ridges where temps are above freezing. These warm temps may affect the glide cracks.
-PRECIP: There has been zero (0.0 inches) precip that has fallen in 24 hours, and NOAA is forecasting zero (0.0 inches) of precip for today.
-WIND: Has been light with moderate gusts in the past 24 hours in the mountains around Turnagain Pass. Once again, NOAA is forecasting strong wind this evening through Sunday near Whittier.
The avalanche danger rating will remain at LOW with pockets of MODERATE. Due to glide cracks that are widespread throughout the region.
The glide cracks and glide avalanches continue to be present, with new ones being observed region-wide on a daily basis. Be aware of your travel routes and try to avoid spending time below the cracks. Research has shown it is nearly impossible to predict when these cracks will release. The only way to reduce your risk from glide avalanches is to avoid traveling below the obvious cracks.
This photo shows the South face of Cornbiscuit taken on 11-16-10. For scale take note that the crack is 4-6 feet deep. The glide crack on the left hand side of this photo has already avalanched; while, the glide crack on the right is still a hazard that could avalanche any day. Avoid traveling underneath glide cracks just like the one on the right hand side of this photo.
AnCNFAIC Staff area of concern are pockets of poorly structured snow along ridges and prominent terrain features where small human-triggered avalanches are possible. The most likely terrain for these avalanches will be unsupported pockets above cliff bands or on basketball shaped rollovers.
The Nation Weather Service weather forecast for:
WESTERN PRINCE WILLIAM SOUND-
500 AM AKST SAT NOV 20 2010
…STRONG WIND THIS EVENING THROUGH SUNDAY AFTERNOON NEAR WHITTIER…
.TODAY…MOSTLY SUNNY. PATCHY FOG. HIGHS IN THE LOWER 20S TO
LOWER 40S…COOLEST INLAND. LIGHT WINDS EXCEPT NORTH WIND INCREASING
TO 15 TO 25 MPH IN THE AFTERNOON NEAR SEWARD. NEAR WHITTIER…LIGHT
WINDS BECOMING SOUTHWEST 15 TO 30 MPH IN THE AFTERNOON.
.TONIGHT…MOSTLY CLEAR. LOWS IN THE LOWER TEENS TO
LOWER 30S…COOLEST INLAND. VARIABLE WIND TO 10 MPH INLAND. NEAR
SEWARD…NORTH WIND 15 TO 25 MPH. NEAR WHITTIER…SOUTHWEST WIND 30
TO 45 MPH.
.SUNDAY…MOSTLY SUNNY IN THE MORNING THEN BECOMING PARTLY
CLOUDY. HIGHS IN THE LOWER 30S TO MID 40S…COOLEST INLAND. LIGHT
WINDS INLAND. NEAR SEWARD…NORTH WIND 15 TO 25 MPH. NEAR
WHITTIER…SOUTHWEST WIND 25 TO 40 MPH WITH GUSTS TO 50 MPH.
TEMPERATURE / PRECIPITATION
SEWARD 40 28 44 / 0 0 0
GIRDWOOD 27 15 32 / 0 0 0
WEATHER STATION SUMMARY for Turnagain Pass:
3800′-Sunburst Wx Station
Temp (5am): 34 (2 degrees warmer than yesterday morning) Temps have mostly been above freezing at this elevation for the past 24 hours with a max temp of 38 degrees.
Winds: In last 24 hours winds have been light averaging 1-11mph with a moderate max gust of 18 mph
2400′-Seattle Ridge Wx Station
Temp (5am): 29 (4 degrees colder than yesterday morning). Warm temps in past 24 with a max temp of 37 degrees
Winds: In last 24 hours have been light averaging 1-12mph with a light max gust of 12mph.
1800′-Center Ridge Wx Station
Temp (5am): 25 (1 degree warmer than yesterday morning)
Precip: 0.0 inches of water, 45″ of total snopack depth (1 inch less due to settlement)
The next advisory will be issued tomorrow Sunday morning 11/21/2010 at 7am. If you get out in the backcountry send us your observations using the button at the top of this page or call and leave a message at 907-754-2369. Thanks and have a great day.