CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST


Masaoka Shiki
Again and again
Asking how deep
Snow fell
ISSUED AT 08:35 WEDNESDAY DECEMBER 01 2021
VALID FROM : WEDNESDAY 01 -- MONDAY DECEMBER 06 2021

GENERAL SYNOPSIS
High 1037 hpa NNE close to Azores (1035, Terceira). • Powerful low 975 hpa W of Denmark, moving fairly quickly E and driving W stream across the Alps • Linked cold front, currently extending North Sea to far W of Coruña, is expected to reaching our slopes early in the afternoon; there, it shall trigger locally moderate precipitation, say 8‑10 mm until evening, with dropping snow limit 1300->1000 m. • Following tail will keep producing shower overnight, locally fairly heavy at first, then gradually lighter and more scattered thereafter. Such showery condition might persist until Thursday evening, making snow drop again towards 500 m. • Therefore, 25-40 cm accumulation toward 1500 m to be considered until expected next lull by Friday. • New rainy-snowy unsettled spell likely Saturday-Sunday, possibly heavy.
Avalanche risk 3/5 above 2500 m [ 30/11 • 07:00 ].
TODAY - WEDNESDAY DECEMBER 01
Short milder spell, soon unsettled - mixed rain-snow in the afternoon - windy high up
SKY CONDITION : fleeting and veiled sunny spell among altocumulus cloud patches in the first part of the morning - becoming soon mostly cloudy to overcast overcast from W - ceiling likely to dropping towards 1300-1400 m in the afternoon. Period of sunshine close to 20%.
PRECIPITATION : starting up towards noon (13:00), moderate on the whole, yet occasionally fairly heavy - rain-snow limit rising up towards 1300 m, then dropping towards 1000 m at night - expected snowfall towars 1600 m : 8-12 cm.
WIND - ground level : calm -> SW light.
WIND - mid mountain : WSW moderate - occasionally moderate to strong.
WIND - high mountain : WSW moderate to strong.
TEMPERATURE : low -3°C - high +4°C.
ISOTHERM 0°C : 1500 -> 1900 -> 1600 m.
ISOTHERM -10°C : 4100 -> 3100 m.
OVERNIGHT
Unsettled with snow shower at first - then some lull - windy high up
SKY CONDITION : mostly cloudy to overcast, no visibility in the median altitude range - iso 0°C dropping towards 800-900 m.
PRECIPITATION : snow shower - locally fairly heavy at first - becoming light and scattered towards the latter part - rain-snow limit dropping towards 700 m - expected snowfall towars 1000 m : 5-10 cm.
WIND - aloft : WSW moderate to strong -> W moderate.
TEMPERATURE : low -3°C.
THURSDAY DECEMBER 02
Unsettled and cold Westerlies keep ruling - snow shower, moderate at times
SKY CONDITION : fleeting clear spell likely in the course of the morning - else mostly cloudy to overcast - ceiling likely to dropping towards 1100 m in the afternoon. Period of sunshine close to 5%.
PRECIPITATION : frequent shower - rain-snow limit towards 1100 m, dropping towards 700 m in the afternoon - expected snowfall towars 12 00 m : 10-15 cm.
WIND - aloft : mainly W - moderate -> light.
TEMPERATURE : low -3 °C - high +1°C.
FRIDAY DECEMBER 03
Precipitation lull - fair sunny spells in the afternoon - cold and windy on the whole
SKY CONDITION : low cloud patches likely by dawn, dispelling in the course of the morning - else fair sunny spells in the median altitude range. Period of sunshine close to 60%.
PRECIPITATION : none.
WIND - aloft : N -> NW moderate to strong - occasionally strong.
TEMPERATURE : dropping.
EXTENDED OUTLOOK UNTIL MONDAY DECEMBER 06 2021

Saturday : bad weather owing to large and active disturbance - continuous sustained precipitation - changeable rain-snow limit between 700 and 1000 m - strong Westerlies high up decreasing towards evening. Sunday : uncertain - in the tail of Saturday's disturbance, sitll fairly active - rather unsettled - snow shower in the morning, becoming light and scattered over afternoon hours. Sunday : uncertain - snow shower likely until noon or so - possible sunny spell in the afternoon.

Forecast reliability : fairly good until Friday - poor thereafter.

ReportsAs a reminder, today in Chamonix, the sun rises at 07:54:21 and goes down at 16:49:14.
Chamonix - ville
45.55 N 6.51 E - Altitude 1020 m
December 01 08:00
Temperature -2.7°C
Relative humidity 95%
Wind 0 km/h
Sea level pressure 1016 hpa - falling slowly
Pressure at 1042 m 900 mb
Precipitation last 6h 0 mm
Skies cloudy with clear outbreaks
Visibility 75000 m
Altitude 3845 m
December 01 08:00
Temperature -10.5°C
Wind WSW 15-70 km/h
Altitude 2250 m
December 01 08:00
Snow depth 20 cm
Wind WSW 25 km/h
Gusts WSW 45 km/h
Temperature -2.2°C