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Intelligence
Season & Weather Guide
Best Time for Sin La Pass Expedition — Month-by-Month Guide
June and September are the only logical windows for this 18k crossover.
Pass Window
When is it climbable?
Microscopically thin windows in June and September. Avoid monsoon at all costs.
Season at a Glance
Editor's Notes
May to June and September to October are the ideal windows, though high-altitude weather remains unpredictable and freezing.
Month by Month
What each month looks like
January
Pass ClosedConditions
Deep winter. The high pass is completely buried and impassable.
Crowds
none
Impassable winter snowpack.
Closed. Extreme winter conditions.
February
Pass ClosedConditions
Deep winter. The high pass is completely buried and impassable.
Crowds
none
Impassable winter snowpack.
Closed. Extreme winter conditions.
March
Pass ClosedConditions
Deep winter. The high pass is completely buried and impassable.
Crowds
none
Impassable winter snowpack.
Early season. Deep snow accumulations.
April
Pass ClosedConditions
Shoulder season. Highly unstable snow conditions and narrow weather windows.
Crowds
low
Unstable snow conditions.
Early season. Deep snow accumulations.
May
Pass OpenConditions
Crowds
low
Prime pre-monsoon window. Good snow stability.
June
Pass OpenConditions
Residual snow navigation. Clear morning windows.
Crowds
low
Prime pre-monsoon window. Good snow stability.
July
Conditions
Monsoon season. Extreme objective hazards including rockfall, avalanches, and swollen rivers.
Crowds
low
Severe monsoon hazards.
Monsoon danger. Landslides and severe rains.
August
Conditions
Monsoon season. Extreme objective hazards including rockfall, avalanches, and swollen rivers.
Crowds
none
Severe monsoon hazards.
Monsoon danger. Landslides and severe rains.
September
Pass OpenConditions
Pristine visibility. Deep cold winds.
Crowds
low
Crystal clear skies. Best visibility of the year.
October
Pass OpenConditions
Crowds
low
Crystal clear skies. Best visibility of the year.
November
Pass ClosedConditions
Shoulder season. Highly unstable snow conditions and narrow weather windows.
Crowds
none
Unstable snow conditions.
Winter setting in. Sub-zero temperatures rapid.
December
Pass ClosedConditions
Deep winter. The high pass is completely buried and impassable.
Crowds
none
Impassable winter snowpack.
Closed. Extreme winter conditions.
Photography & Light Conditions
Sunrise Spot
Sin La Summit
Recommended Lenses
Astrophotography
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