CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST


Matsuo Bashō
On a mountain path
Something might charm you
A wild violet
ISSUED AT 08:40 WEDNESDAY SEPTEMBER 17
VALID FROM : WEDNESDAY SEPTEMBER 17 ‑‑ UNTIL : MONDAY SEPTEMBER 22 2014

GENERAL SYNOPSIS
High 1028 hpa, Baltic Lands, drifting slowly towards Russia. Low 993 hpa northwest of Portugal, almost stationary. Weak pressure gradient over the Alps. The southwest altitude flow is fairly light, mild, at times humid and unsettled. Fœhn wind puffs likely in the Valley until Friday.
TODAY - WEDNESDAY SEPTEMBER 17
Fairly sunny in the morning ‑ fœhn wind puffs ‑ afternoon thunderstorm risk
SKY CONDITION : clear or partly cloudy early in the morning ‑ becoming cloudy with sunny spells ‑ at times mostly cloudy in the afternoon. Period of sunshine close to 50%.
PRECIPITATION : scattered thundery showers or thunderstorm likely from noon ‑ rain‑snow limit towards 3300 m.
WIND - ground level : variable light to moderate ‑ fœhn wind puffs.
WIND - mid mountain : SE light to moderate ‑> S light.
WIND - high mountain : SSW ‑> SW light to moderate.
TEMPERATURE : low +12°C - high +24°C.
ISOTHERM 0°C : 3400 ‑> 3600 ‑> 3500 m.
ISOTHERM -10°C : 5100 ‑> 5200 m.
OVERNIGHT
Cloudy at times ‑ fœhn wind puffs ‑ slight shower risk
SKY CONDITION : slightly decreasing cloud in the first part of the night ‑ persistent cloud patches crossing over from the southwest.
PRECIPITATION : decreasing thundery shower risk.
WIND - aloft : SW light to moderate ‑ fœhn wind puffs in the valley.
TEMPERATURE : low +13°C.
THURSDAY SEPTEMBER 18
Uncertain ‑ very mild ‑ cloudy with shower risk ‑ fœhn wind puffs
SKY CONDITION : cloudy with sunny spells to mostly cloudy. Period of sunshine close to 40%.
PRECIPITATION : scattered thundery showers or thunderstorm ‑ rain‑snow limit towards 3400 m.
WIND - aloft : SW light to moderate ‑ fœhn wind puffs in the valley.
TEMPERATURE : low +13 °C - high +23°C.
FRIDAY SEPTEMBER 19
Uncertain ‑ very mild ‑ hazy skies ‑ light fœhn wind likely
SKY CONDITION : partly cloudy to mostly cloudy ‑ high cloud, fairly thick at times ‑ cumulus cloud growing in the afternoon. Period of sunshine close to 55%.
PRECIPITATION : afternoon thundery shower risk.
WIND - aloft : SW ‑> WSW light to moderate ‑ possible fœhn wind puffs in the valley.
TEMPERATURE : steady.
EXTENDED OUTLOOK UNTIL MONDAY SEPTEMBER 22 2014

Saturday to Monday : increasing diurnal instability ‑ fairly sunny in the morning ‑ considerable cloud increase along the day ‑ afternoon shower or thunderstorm likely. very uncertain.

Forecast reliability : poor.

ReportsAs a reminder, today in Chamonix, the sun rises at 07:13:39 and goes down at 19:40:07.
45.55 N 6.51 E - Altitude 1040 m
17 September 08:00
Temperature +12°C
Relative humidity 80%
Wind NE 15 km/h
Sea level pressure 1019 hpa - rising
Pressure at 1042 m 896 mb
Precipitation last 6h 0.0 mm
Skies partly cloudy - some cloud running over from italy
Visibility 60000 m
Altitude 3845 m
17 September 08:00
Temperature -3°C
Wind S 20 km/h
Altitude 2250 m
17 September 08:00
Snow depth 0 cm
Wind 10 km/h
Gusts 15 km/h
Temperature +8°C