CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST


Tomiyasu Fūsei
There's nothing
He doesn't know—
The cat on the stove
ISSUED AT 08:40 SUNDAY APRIL 20
VALID FROM : SUNDAY APRIL 20 ‑‑ UNTIL : FRIDAY APRIL 25 2014

GENERAL SYNOPSIS
Extended low system with weak gradient pressure field, Madeira to the Mediterranean and further to Germany, linked to an altitude cold drop, Central to Northwestern France. Temporary improvement until the first part of the afternoon, then rainy deterioration from the southwest towards the evening and during the following night. Current weather pattern is expected to persisting during the main part of the week causing very unsettled condition, favorable to showers, mainly in the afternoon..
TODAY - SUNDAY APRIL 20
Slightly milder ‑ fairly sunny morning ‑ deterioration in the afternoon
SKY CONDITION : early morning fog down in the valley, vanishing quickly ‑ otherwise partly cloudy in the morning ‑ becoming mostly cloudy from the southwest during the afternoon. Period of sunshine close to 50%.
PRECIPITATION : running over from the south towards the latter part of the afternoon ‑ rain‑snow limit towards 2000 m, dropping.
WIND - ground level : variable light ‑ possible fœhn wind puffs towards the middle of the day.
WIND - mid mountain : mainly SE ‑ light.
WIND - high mountain : WSW ‑> SW light to moderate.
TEMPERATURE : low +1°C - high +14°C.
ISOTHERM 0°C : 2200 ‑> 2500 ‑> 2200 m.
ISOTHERM -10°C : 3700 ‑> 4100 ‑> 3900 m.
OVERNIGHT
Light scattered rain
SKY CONDITION : overcast, then mostly cloudy.
PRECIPITATION : light and scattered until the end of the night ‑ rain‑snow limit towards 1900 m.
WIND - aloft : SW light to moderate ‑> SSW light.
TEMPERATURE : low +3°C.
MONDAY APRIL 21
Often mainly cloudy ‑ sunny spells towards noon ‑ showers
SKY CONDITION : mostly cloudy early in the morning ‑ becoming cloudy with sunny spells ‑ increasing fat cloud during the afternoon. Period of sunshine close to 20%.
PRECIPITATION : light and scattered early in the morning ‑ dry towards the middle of the day ‑ showers probably resuming in the afternoon, locally moderate ‑ rain‑snow limit towards 2000‑2200 m.
WIND - aloft : SSW light ‑> SW light to moderate.
TEMPERATURE : low +3 °C - high +14°C.
TUESDAY APRIL 22
Cloudy with sunny spells in the morning ‑ showers likely in the afternoon
SKY CONDITION : partly cloudy in the morning ‑ becoming cloudy, then mostly cloudy in the afternoon. Period of sunshine close to 45%.
PRECIPITATION : afternoon shower.
WIND - aloft : W ‑> S light.
TEMPERATURE : slightly dropping lows ‑ slightly rising highs.
EXTENDED OUTLOOK UNTIL FRIDAY APRIL 25 2014

Wednesday : very uncertain ‑ fairly sunny in the morning ‑ cloudy with shower risk in the afternoon. Thursday : very uncertain ‑ fairly sunny in the morning ‑ afternoon shower slight risk. Friday : very uncertain ‑ active disturbance possibly crossing over.

Forecast reliability : poor.

Avalanche risk becoming considerable (3/5) above 2500 m.
ReportsAs a reminder, today in Chamonix, the sun rises at 06:36:44 and goes down at 20:25:59.
45.55 N 6.51 E - Altitude 1040 m
20 April 08:00
Temperature +1°C
Relative humidity 100%
Wind 0 km/h
Sea level pressure 1007 hpa - falling slowly
Pressure at 1042 m 888 mb
Precipitation last 6h 0.0 mm
Skies partly cloudy - fog down in the valley
Visibility 60000 m
Altitude 3845 m
20 April 08:00
Temperature -12°C
Wind SE 30 km/h
Altitude 2250 m
20 April 08:00
Snow depth 70 cm
Wind 5 km/h
Gusts 20 km/h
Temperature 0°C