CHAMONIX VALLEY AND MONT-BLANC AREA WEATHER FORECAST
ISSUED AT 18:55 ON MONDAY JULY 06, 2015
VALID FROM : MONDAY JULY 06 -- UNTIL : SUNDAY JULY 12 2015
Rising from the shoulder
My paper robe
Extended low system, west of the British Isles to Scandinavia. High 1021 hpa, Northeastern France, weakening. Altitude pressure field is weakening as well over the Alps despite the hot air which continues to stream high up from the western part of the Maghreb. Sun and scorching heat will continue to rule until Tuesday afternoon. A short thunderstorm spell is expected in the evening, preceding the cold front of the low which should have deepen over Southern Scandinavia. Actual activity of this cold front is still difficult to figure out for now. High condition resuming from Thursday and probably becoming hot from Friday.
MONDAY EVENING JULY 06 - AND OVERNIGHT
SKY CONDITION : clear in the first part of the night - thin high cloud crossing over from the southeast shortly before dawn.
PRECIPITATION : none.
WIND - ground level : variable light.
WIND - mid mountain : WSW light.
WIND - high mountain : W light to moderate -> WSW moderate.
TEMPERATURE : low +17°C.
ISOTHERM 0°C : 4700 -> 4800 -> 4600 m.
ISOTHERM -10°C : 6300 -> 6100 m.
Bad mountaineering condition. Melted snow is not re-freezing. Unusually dry atmosphere towards the end of the night.
ROAD CONDITION ••••• : @ 06:30, dry roadways.
TOMORROW - TUESDAY JULY 07
SKY CONDITION : partly cloudy at times early in the morning with thin high cloud crossing over, then clear - becoming cloudy to mostly cloudy towards the end of the afternoon. period of sunshine close to 80%.
PRECIPITATION : pre-frontal thunderstorm likely towards the evening, possibly locally heavy - rain-snow limit towards 4100 m.
WIND - ground level : variable light to moderate - possible thunderstorm gust in the evening.
WIND - mid mountain : WSW light -> WNW moderate ‑ possible thunderstorm gust in the evening.
WIND - high mountain : WSW moderate -> moderate to strong.
TEMPERATURE : low +17°C - high +35°C.
ISOTHERM 0°C : 4600 -> 4300 m.
ISOTHERM -10°C : 6100 -> 5900 m.
Unusually dry atmosphere depending on a light fœhn wind pattern. Very uncertain.
TUESDAY TO WEDNESDAY NIGHT - JULY 07 TO 08
SKY CONDITION : mostly cloudy to overcast.
PRECIPITATION : thunderstorm crossing over in the first part of the night, possibly heavy - showers becoming scattered later - rain-snow limit towards 4000 m, dropping.
WIND - aloft : WSW -> W moderate to strong - strong at times.
TEMPERATURE : low +15°C.
WEDNESDAY JULY 08
SKY CONDITION : locally mostly cloudy early in the morning - becoming cloudy with bright sunny spells, then partly cloudy towards the evening. Period of sunshine close to 70%.
PRECIPITATION : possible isolated remaining shower early in the morning.
WIND - aloft : W -> WNW moderate to strong.
TEMPERATURE : low +15 °C - high +24°C.
THURSDAY JULY 09
SKY CONDITION : clear or partly cloudy - some cumulus cloud over the massifs in the afternoon. Period of sunshine close to 100%.
PRECIPITATION : none.
WIND - aloft : WNW moderate -> NW light to moderate.
TEMPERATURE : low +10°C - high +23°C.
EXTENDED OUTLOOK UNTIL SUNDAY JULY 12 2015
Friday to Sunday : fair sunny weather ‑ gradually back to scorching heat in the afternoon.
Forecast reliability : poor.