Avalanche Advisory: Tuesday - Jan 29, 2019

THIS AVALANCHE ADVISORY EXPIRED ON January 30, 2019 @ 6:33 am
Avalanche Advisory published on January 29, 2019 @ 6:33 am
Issued by Steve Mace - ESAC

LOW avalanche danger exists at all elevations today.  Expect fresh wind slabs development in the afternoon and evening hours if we see significant snowfall accumulation.  These sensitive wind slabs are likely to be small and confined to leeward terrain features at upper elevations.  Generally, safe avalanche conditions exist, but that does not mean avalanches are impossible.  It is always important to practice safe travel techniques and limit your exposure to one person at a time.

1. Low

?

Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

?

Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

?

Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Wind Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

With 1-3” of snow expected at upper elevations and southwest winds gusting to 35mph it is possible that we will see small sensitive wind slabs develop on northerly aspects at upper elevations.  This is more of a problem for the afternoon and evening hours and is dependent mainly on snowfall totals.  Keep an eye out for uneven snow surfaces and blowing or drifting snow, as these are all signs of nearby wind loading.   Be particularly cautious in areas where terrain features encourage drifting such as the leeward sides of ridgelines and the sidewalls of gullies. 

advisory discussion

Removing persistent slab from the problem list today was not done without a lot of thought and concern. Although poor structure is still present in the snowpack in many areas, significant time has passed without reported incidents and the last few days of warm spring like conditions have helped to settle out and heal our snowpack.  This weekend’s storm may bring a large enough load to stress these deeper weak layers and reawaken the problem but for the time being it is very unlikely that we will see a persistent slab avalanche.  Localized snowpack assessments and conservative terrain choices are always recommended. When in doubt it is best to just avoid suspect terrain.

Weather and CURRENT CONDITIONS
weather summary

Expect mostly cloudy skies with scattered showers possible throughout the day.   Snow totals are expected to be small.  We could see up to 2” at upper elevations, but it is likely we will see less. With snow level rising to 8000’ this afternoon there is a chance of rain showers at lower elevations.  Temperatures will be warm with daytime highs in the mid 30’s at upper elevations with light winds expected out of the southwest.  Temperatures will drop below freezing tonight as the brief storm moves out of the area. Less than 1” expected this evening.

Our warm, mild weather continues tomorrow with cloudy skies, temperatures expected in the mid 30’s and light winds.  

Models are showing a more significant storm system moving into the area later this week with our greatest chance of significant precipitation over the weekend.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy. Chance of snow through the day. Chance of rain in the afternoon. Snow levels 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 35%. Mostly cloudy. Chance of snow in the evening. Snow levels 7500 feet. Chance of precipitation is 30%. Mostly cloudy.
Temperatures: 38 to 46. deg. F. 22 to 27. deg. F. 38 to 46. deg. F.
Mid Slope Winds: Southwest 10 to 15 mph in the morning becoming light. Gusts up to 30 mph. Light winds. Light winds.
Expected snowfall: 30% probability up to 1 inch. 70% probability no accumulation. | SWE = less than 0.10 inch. in. 30% probability up to 1 inch. 70% probability no accumulation. | SWE = trace amounts. in. None in.
Over 10,000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy. Chance of snow. Snow levels 8000 feet. Chance of precipitation is 40%. Mostly cloudy. Chance of snow in the evening. Snow levels 8000 feet decreasing to 7000 feet after midnight. Chance of precipitation is 40%. Mostly cloudy.
Temperatures: 30 to 36. deg. F. 18 to 23. deg. F. 30 to 36. deg. F.
Ridge Top Winds: Southwest 15 to 25 mph with gusts to 35 mph. Light winds. Light winds.
Expected snowfall: 40% probability up to 2 inches. 60% probability no accumulation. | SWE = less than 0.10 inch. in. 40% probability up to 1 inch. 60% probability no accumulation. | SWE = less than 0.10 inch. in. None in.
Disclaimer
This Avalanche Advisory is designed to generally describe avalanche conditions where local variations always occur. This product only applies to backcountry areas located outside established ski area boundaries. The information in this Avalanche Advisory is provided by the Eastern Sierra Avalanche Center, who is solely responsible for its content.

ESAC receives support from ...