CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST


Matsuo Bashō
Heat shimmer
Rising from the shoulder
My paper robe
ISSUED AT 07:45 FRIDAY AUGUST 7
VALID FROM : FRIDAY AUGUST 7 ‑‑ UNTIL : WEDNESDAY AUGUST 12 2020

GENERAL SYNOPSIS
Powerful high 1028, Baltic states, extending a ridge 1020 up to Northwest Alpine Range and reinforced by Saharan originated altitude ridge. That widespread anticyclonic pattern will keep sheltering our Region until Sunday noon, under a kind of hot and stable air cupola where temperature highs might climb above 31°C towards 1000 m. • Air mass is expected to becoming slightly unstable by Sunday afternoon, without further consequence than locally well developed cumulus cloud over the massifs.
TODAY - FRIDAY AUGUST 7
Fair weather ‑ barely cool early in the morning ‑ scorching heat in the afternoon
SKY CONDITION : clear skies likely all over the area. Period of sunshine close to 100%.
PRECIPITATION : none.
WIND - ground level : calm ‑> variable light ‑ thermal SW light to moderate, early afternoon.
WIND - mid mountain : mainly N ‑ very light.
WIND - high mountain : N ‑> NNW light ‑ occasionally light to moderate.
TEMPERATURE : low +9°C - high +30°C.
ISOTHERM 0°C : 4600 m.
ISOTHERM -10°C : 6100 ‑> 6200 m.
OVERNIGHT
Fair summer night ‑ clear skies ‑ mild in the Valley by dawn
SKY CONDITION : clear ‑ excellent radiation condition, though with iso 0°C towards 4600 m, probably setting a limit to snow‑surface re‑freezing towards 4000 m.
PRECIPITATION : none.
WIND - aloft : NNW ‑> N light ‑ occasionally light to moderate at first.
TEMPERATURE : low +13°C.
SATURDAY AUGUST 8
Fair weather ‑ becoming fairly soon warm in the morning ‑ afternoon scorching heat
SKY CONDITION : clear or occasionally very thinly veiled at high altitude. Period of sunshine close to 100%.
PRECIPITATION : none.
WIND - aloft : N light ‑> NNW or variable very light.
TEMPERATURE : low +12 °C - high +31°C.
SUNDAY AUGUST 9
Fair weather ‑ scorching heat, quite sultry ‑ cumulus cloud over the massifs later
SKY CONDITION : clear or partly cloudy ‑ cumulus cloud growing noticeably over the massifs in the course of the afternoon. Period of sunshine close to 90%.
PRECIPITATION : none.
WIND - aloft : mainly N ‑ very light ‑ occasionally light.
TEMPERATURE : steady or slightly dropping highs.
EXTENDED OUTLOOK UNTIL WEDNESDAY AUGUST 12 2020

Monday : fairly sunny ‑ sweltering heat (28°C), yet sultry with more convection than previously ‑ thundery shower risk later. Tuesday : uncertain ‑ fairly sunny ‑ sweltering heat ‑ late afternoon thundery shower slight risk. Wednesday : uncertain ‑ sunny morning ‑ sweltering heat ‑ afternoon thunderstorm risk.

Forecast reliability : fairly good until Sunday ‑ poor thereafter.

ReportsAs a reminder, today in Chamonix, the sun rises at 06:23:32 and goes down at 20:52:51.
45.55 N 6.51 E - Altitude 1020 m
August 7 - 08:00
Temperature +11°C
Relative humidity 88%
Wind 0 km/h
Sea level pressure 1023 hpa - steady
Pressure at 1042 m 901 mb
Precipitation last 6h 0.0 mm
Skies clear
Visibility 95000 m
Altitude 3845 m
August 7 - 07:00
Temperature +4°C
Wind NNW 25 km/h
Altitude 2250 m
August 7 - 07:00
Snow depth 0 cm
Wind WSW 4 km/h
Gusts 11 km/h
Temperature +13°C