Wayne Flann Avalanche Blog: April 8, 2022

YESTERDAY:

07:00 Hrs Thursday morning. -4 Deg C with a 40-50 KPH SE wind.

Sunny breaks in the am.

Mostly overcast skies but great light.

Nice skiing on False Face.

Thursday afternoon 14:30 Hrs.

19:00 Hrs. Snowing lightly. 0 Deg C with a 60-85 KPH SE wind.

Weather Observations for April 8, 2022 taken at 06:00 Hours.

2240 meters -7, Winds were 85-115 KPH SE--Horstman Hut

2180 meters -6, Winds were 75-100 KPH SE--Whistler Peak

1860 meters -4, Winds were 35-65 KPH S--Rendezvous

1835 meters. -4, Winds were 30-50 KPH ESE--Roundhouse

1650 meters -2, 2 cm in 12 Hrs, 2 cm with 24.1 mm in 24 Hrs. Base 284 cm --Pig Alley

1570 meters -1, trace in 12 Hrs, trace with 16.7 mm in 24 Hrs. Base 212 cm. Catskinner

660 meters +4, Valley Temp, Max temp Yesterday was +15.1, 3.4 mm of precip yesterday

As of 07:00 Hrs this am we have broken cloud, variable visibility and snowing lightly.

FORECAST:

A cool upper trough in a Southerly flow aloft will bring mostly overcast weather with periods of light precipitation. Some breaks this am and later in the pm. Freezing level at around 1000 m and should slowly drop to surface by tonight. Weak upper trough for Saturday with a mix of sun and cloud with some snow showers. Mostly overcast for Sunday with some sunny breaks in the evening. Periods of light precipitation during the day. Monday sees a ridge build with mostly sunny skies. More of the same for Tuesday. Guesstimates: 5-10 cm by Saturday am, 1-4 cm by Sunday am, trace-1 cm by Monday am, 0 cm by Tuesday am, 0 cm by Wednesday am.

GOES IR Image from this am.

GOES 17 ABI image 2022/04/08. 05:00 Hrs.

Low sending a cold front for Friday. High sends some intermittent sunny breaks. Cooling.

Periods of light precipitation, should dry out at around 18:00 Hrs Friday evening.

Southerly flow aloft.

Cold upper trough will bring unsettled weather with some snow showers Saturday.

Periods of very light precipitation Saturday.

Cool upper level trough will bring unsettled weather on Sunday. Cool temps, warming up Late pm.

Dirty ridge with some showers in the mix Sunday. Mostly cloudy with afternoon sunny breaks.

High pressure strengthens with sunny skies in the forecast.

Mostly sunny skies on Tuesday.

AVALANCHE ACTIVITY:

Ma Sz 2.5 Appa Glacier. Sledder rode out of avalanche. Apr 6, 2022. Toby Salin Pic

Sz 2 Sr (skier remote) Helisking on Thursday. Second skier triggered storm slab. Jerome David Pic

Wet Loose snowballing yesterday afternoon.

Avalanche mitigation on Whistler produced Sz 1-2 Xh cornice control. A Sz 2 storm slab Xh.

Avalanche mitigation on Blackcomb yesterday produced some holes. Xh.

Roof Avalanche.

Wet Loose on North facing slopes with rapidly rising temperatures yesterday.

FROM AVALANCHE CANADA-SEA TO SKY:

Avalanche Summary

High freezing levels and a mix of rain and snow overnight are expected to produce a natural avalanche cycle.

On Wednesday, several natural and rider triggered storm slab avalanches were reported on all aspects to size 2. Previous natural activity from the storm was observed to size 3. Several cornice falls were also reported, some triggered slab avalanches on the slope below. Most avalanches have failed on the buried crust from late March.

On Tuesday, rider, natural and explosive triggered avalanches were reported to size 2.5. Small avalanches were also remotely triggered, indicating the sensitivity of the recent storm snow.

Snowpack Summary

Up to 40 mm of precipitation overnight with falling freezing levels will create a mixed bag of conditions on Friday, as snow continues to accumulate.

High elevations can expect up to 40 cm of fresh wind affected storm snow, that will likely be redistributed into deeper deposits on north and east facing slopes over a crust or moist snow. Another widespread and supportive crust is buried 60-100 cm deep, below recent settling storm snow. This crust has recently been very reactive to human and natural triggers.

Snow will transition to mixed precipitation and rain as elevation decreases. The lowest elevations will likely hold wet surface snow or a crust from heavy overnight rainfall.

The middle and lower snowpack are generally strong and well bonded.

INFORMATION & OBSERVATIONS:

Lenticular Clouds.