CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST

From http://chamonix-meteo.com

ISSUED AT 08:10 SATURDAY AUGUST 24

GENERAL SYNOPSIS

High formerly crossing over France yesterday leaves somewhat lower pressure field with looser gradient in the north of the Alpine Range, while drifting away over Belarus (1028 hpa, there, this morning). It drives mainly north light winds along Northern Alps in a fairly stable and dry air mass. • Southward, the altitude cold cut‑off which lies currently over Tuscany keeps drifting away eastward, thus loosing gradually its influence regarding atmosphere’s instability and draught. • No deterioration to be expected therefore until Monday evening : current summer feeling will remain unaffected and, on the contrary, with noticeable increase above seasonal average of temperature highs (about 8°C, by then).

TODAY - SATURDAY AUGUST 24

Fair summer weather ‑ hot in the afternoon ‑ cumulus cloud growing over the massifs

SKY CONDITION : clear or partly cloudy ‑ locally cloudy in the afternoon due to cumulus cloud growth. Period of sunshine close to 80%.
PRECIPITATION : none over the northern slopes of the high massifs ‑ shower risk noticeably higher, however, over the Italian slopes towards the end of the afternoon, rain‑snow limit towards 3800 m.
WIND - ground level : NE light ‑ afternoon thermal SW shift ‑ calm in the evening.
TEMPERATURE : low +10°C - high +26°C.
ISOTHERM 0°C : 4000 ‑> 4200 ‑> 4100 m.
ROAD CONDITION  : recent snow shower. Locally whitened roadways. (Sun. 06:15).

OVERNIGHT

Fair summer night, mild in the median altitude range

SKY CONDITION : clear or partly cloudy after evening cumulus cloud dispelling ‑ good radiation condition high up, yet with iso 0°C above 4000 m, thus short lasting snow surface re‑freezing.
PRECIPITATION : none.
WIND - aloft : N ‑> NNW light.
TEMPERATURE : low +9°C.

SUNDAY AUGUST 25

Fair summer weather, cool by dawn, hot in the afternoon

SKY CONDITION : clear or partly cloudy in the morning ‑ less afternoon cumulus cloud growth over the massifs than previously. Period of sunshine close to 90%.
PRECIPITATION : none.
WIND - aloft : NNW light.
TEMPERATURE : low +7 °C - high +27°C.

MONDAY AUGUST 26

Fair summer weather, cool by dawn, hot in the afternoon

SKY CONDITION : clear or partly cloudy ‑ some cumulus cloud over the massifs later. Period of sunshine close to 90%.
PRECIPITATION : none.
WIND - aloft : NNW ‑> NW light ‑ thermal slope breezes in the afternoon.
TEMPERATURE : steady or slightly rising highs.

EXTENDED OUTLOOK UNTIL THURSDAY AUGUST 29 2019

Tuesday : fairly sunny, hot in the afternoon ‑ cloud running over from south towards the evening ‑ foehn puffs. Wednesday : south to southeast, mostly light, yet unstable ‑ foehn generated sunny spells in the morning ‑ thundery shower later ‑ still unseasonably hot. Thursday : changeable, somewhat cooler ‑ fair sunny spells at first ‑ scattered shower with possible thunderstorm in the afternoon.