- Admin
- #1
The Canadian Avalanche Centre will issue a Special Public Avalanche Warning for the period of Friday, January 15 to Sunday, January 17.
We apologize for the short notice on this action. Our decision to issue a warning evolved rapidly based on an unfavourable weather forecast that delays cooling beyond the weekend as well as continued reports of avalanche activity related to persistent weak layers in the snowpack. These reports came from many sources. Here are our key thoughts on the need for this warning:
SPAW
January 14, 2010
What’s the problem?
We’re waiting for the freeze and it’s not coming
There is a main persistent weak layer and a couple of secondary ones with more loading expected. Cooler weather will greatly improve this situation but the forecast is not promising
Warm temperatures, rain at low elevations, heavy snow at higher elevations, and strong winds is producing cycles of avalanche activity involving both the old, deeply buried weak layers and storm snow layers.
Snow and wind are expected to slow down or stop during the weekend but warm temperatures are forecast to continue. Things are not expected to improve significantly until sometime next week after several days of cooler weather.
Even though fewer avalanches are occurring, those that are being triggered are larger and more destructive. This is a common recipe for avalanche fatalities: downward trending avalanche activity with upward trending consequences.
Where is the problem most pronounced?
The magnitude of the problem does not decrease at lower elevations as it often does: although the root causes are different, significant hazard exists at Treeline and Below Treeline as well as in Alpine elevations.
All aspects.
The Northern Rocky Mountains, the Cariboo Mountains, the eastern Monashee Mountains, the Selkirk Mountains, and the Purcell Mountains.
This includes riding areas accessed from and around:
Tumbler Ridge
Grande Prairie
Prince George
Grande Cache
Dawson Creek/Ft. St. John
Revelstoke
Golden
McBride
Valemount
Blue River
Wells
Williams Lake
Clearwater
Invermere
Nakusp
New Denver
Kaslo
How to manage risk:
Check the CAC forecasts at Welcome to avalanche.ca for the most current and up to date information to help you plan your trip.
Wait until several days of cool weather have stabilized the snowpack.
Increase your margins of safety even if you do not observe any avalanche activity.
Travel Recommendations:
Stick to flat terrain not threatened from above
One at a time when crossing avalanche paths.
Regroup in heavy timber or in obvious non-avalanche terrain
Boondocking in very low angle terrain with no large open slopes above.
Highmarking is not recommended.
Your feedback on this action is welcome as always. Normally we attempt to issue a pre-warning with sufficient advance time so that you can offer us your insights as well as prepare for any additional workload. Once again I apologize for the quick turn around this time.
Best Regards,
John Kelly,
Operations Manager,
Canadian Avalanche Centre,
Revelstoke, BC
We apologize for the short notice on this action. Our decision to issue a warning evolved rapidly based on an unfavourable weather forecast that delays cooling beyond the weekend as well as continued reports of avalanche activity related to persistent weak layers in the snowpack. These reports came from many sources. Here are our key thoughts on the need for this warning:
SPAW
January 14, 2010
What’s the problem?
We’re waiting for the freeze and it’s not coming
There is a main persistent weak layer and a couple of secondary ones with more loading expected. Cooler weather will greatly improve this situation but the forecast is not promising
Warm temperatures, rain at low elevations, heavy snow at higher elevations, and strong winds is producing cycles of avalanche activity involving both the old, deeply buried weak layers and storm snow layers.
Snow and wind are expected to slow down or stop during the weekend but warm temperatures are forecast to continue. Things are not expected to improve significantly until sometime next week after several days of cooler weather.
Even though fewer avalanches are occurring, those that are being triggered are larger and more destructive. This is a common recipe for avalanche fatalities: downward trending avalanche activity with upward trending consequences.
Where is the problem most pronounced?
The magnitude of the problem does not decrease at lower elevations as it often does: although the root causes are different, significant hazard exists at Treeline and Below Treeline as well as in Alpine elevations.
All aspects.
The Northern Rocky Mountains, the Cariboo Mountains, the eastern Monashee Mountains, the Selkirk Mountains, and the Purcell Mountains.
This includes riding areas accessed from and around:
Tumbler Ridge
Grande Prairie
Prince George
Grande Cache
Dawson Creek/Ft. St. John
Revelstoke
Golden
McBride
Valemount
Blue River
Wells
Williams Lake
Clearwater
Invermere
Nakusp
New Denver
Kaslo
How to manage risk:
Check the CAC forecasts at Welcome to avalanche.ca for the most current and up to date information to help you plan your trip.
Wait until several days of cool weather have stabilized the snowpack.
Increase your margins of safety even if you do not observe any avalanche activity.
Travel Recommendations:
Stick to flat terrain not threatened from above
One at a time when crossing avalanche paths.
Regroup in heavy timber or in obvious non-avalanche terrain
Boondocking in very low angle terrain with no large open slopes above.
Highmarking is not recommended.
Your feedback on this action is welcome as always. Normally we attempt to issue a pre-warning with sufficient advance time so that you can offer us your insights as well as prepare for any additional workload. Once again I apologize for the quick turn around this time.
Best Regards,
John Kelly,
Operations Manager,
Canadian Avalanche Centre,
Revelstoke, BC
