Avalanche Advisory: Saturday - Feb 1, 2020

THIS AVALANCHE ADVISORY EXPIRED ON February 2, 2020 @ 6:21 am
Avalanche Advisory published on February 1, 2020 @ 6:21 am
Issued by Steve Mace - ESAC

Low avalanche danger persists at all elevations today. Unseasonably warm temperatures, clear skies, and light winds will lead to widespread surface warming. Small loose wet avalanches may be possible today, particularly at low elevations and in areas with direct sun exposure.

1. Low

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

1. Low

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

1. Low

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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: Loose Wet
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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
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    Very Large
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    Small

While radiational cooling last night likely led to a weak surface refreeze air temperatures remained above freezing even at upper elevations. Sunny skies and very warm temperatures are expected to continue today. expect surface melting to occur quickly this morning. While the ambient air temperature may be enough to warm surface snow on all aspects at lower elevations, solar radiation will amplify the effect on E-SE-S-SW-W aspects. Be on the lookout for warming surface snow at mid-lower elevations. Wet, sticky snow surface, rollerballs, and pinwheels are all signs of surface warming and may foreshadow larger point release avalanches. Areas around exposed rocks and cliffs may see increased warming and be more problematic.   

advisory discussion

The next couple of days promise to be interesting. Warm spring-like conditions will persist today before an abrupt return to winter conditions tomorrow and very cold temperatures as we move into early next week. Observations yesterday identified variable surface conditions ranging from breakable crusts in the morning to warm sticky snow in the afternoon. A poor freeze overnight coupled with even warmer temperatures and continued sunny skies today will lead to more extensive surface melting.  It will be important to monitor surface warming throughout the day even on shaded aspects. Look for signs of wet instabilities and remember that the consequences of otherwise small avalanches are exasperated when they occur near trees and rocks or above terrain traps.  

recent observations
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1/31-Mammoth Area- Signs of surface warming in the Mammoth Lakes Basin

1/31- June Lake - Surface conditions in the Negatives

1/30 - Virginia Lakes- Snow conditions on the south side of Dunderberg

1/30 - Mammoth Area- Snow conditions in the Sherwins

1/30 - Buttermilk Country - Snow conditions on Mt Emerson

1/30 - Buttermilk Country - Snow conditions on the east face Peaklet

 

 

Weather and CURRENT CONDITIONS
weather summary

 Spring-like conditions will continue to impact our area today.  Temperatures are expected to reach 60°F today below 10,000’ and remain well above freezing in the alpine.  Light westerly winds this morning may increase to moderate speeds this afternoon. 

A strong cold front is expected to impact the area tomorrow bringing cold temperatures, strong winds, and light snow. Early next week looks particularly cold with day time highs expected in the low teens.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Saturday Saturday Night Sunday
Weather: Sunny. Partly cloudy. Partly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 45%.
Temperatures: 50 to 60. deg. F. 27 to 33. deg. F. 33 to 43. deg. F.
Mid Slope Winds: Light winds becoming southwest around 15 mph with gusts to 30 mph in the afternoon. Southwest 15 to 20 mph. Gusts up to 40 mph increasing to 65 mph after midnight. Southwest 20 to 30 mph increasing to 30 to 50 mph in the afternoon. Gusts up to 85 mph.
Expected snowfall: 0 in. 0 in. 70% probability up to 1 inch. 30% probability of 1 to 3 inches. | SWE = less than 0.10 inch. in.
Over 10,000 ft.
Saturday Saturday Night Sunday
Weather: Sunny. Partly cloudy. Partly cloudy then becoming mostly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 50%.
Temperatures: 41 to 49. deg. F. 21 to 27. deg. F. 26 to 34. deg. F.
Ridge Top Winds: West 15 to 20 mph. Gusts up to 30 mph in the afternoon. Southwest 15 to 30 mph with gusts to 45 mph increasing to 30 to 50 mph with gusts to 75 mph after midnight. Southwest 50 to 70 mph with gusts to 80 mph increasing to 60 to 80 mph with gusts to 100 mph in the afternoon.
Expected snowfall: 0 in. 0 in. 70% probability up to 1 inch. 30% probability of 1 to 3 inches. | SWE = less than 0.10 inch. 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.

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