02/11/2019: Today's Update... The Winter Ahead...
The weather is mild and cloudy here in Chatel today, with showery rain. As mentioned on the update yesterday, there may be some snow in the upper half of the ski area tomorrow, however, it is next week when the prospects for some useful snowfall and colder temperatures increase... but more on this on tomorrow's update.
Here is today's rather cloudy scene in Chatel taken at midday...
I've been asked what sort of snow season are we expecting in Chatel this year - which is obviously not a question which can be answered with any degree of accuracy, however, there are various indicators that can be used to give us the faintest of inklings - though it should be noted that these could very easily end up bring wrong! The indicators are listed below and it is normally a question of which of these indicators, or which combination of them, are most important in determining the winter weather pattern.
Without going into detail for each one, and apart from seaweed, the indicators include...
ENSO:(El Nino Southern Oscillation): Whether we see El Nino or La Nina conditions can have an impact on European winter weather, however, the link between an El Nino event and the quality of a snow season in the NW French Alps is tenuous. ENSO is expected to be neutral this winter.
AO / NAO: Arctic Oscillation and North Atlantic Oscillation
Analogues: Looking At Past Patterns of Weather
Seasonal Global Computer Models
Solar Activity (Sun Spots)
QBO (Quasi Biennial Oscillation - high level wind patterns above the equatorial regions)
Arctic Sea Ice & Autumn Siberian Snow Cover
Atlantic Sea Surface Temperatures
SSW’s - Sudden Stratospheric Warmings
The overall leaning from these indicators is for an Atlantic dominated and mild winter for much of Europe. This is not necessarily a bad thing for this part of the Alps as we need an active Atlantic to bring us the snow bearing fronts, though, where the jet stream aligns and hence the resultant track of the lows, will be crucial for determining amounts of precipitation and the snow/rain limits. The not so pleasant scenario of low pressure dominating to the NW of Britain with a persistent and mild high over Iberia could be an issue, which would be a worst case scenario, however, there are reasons to be optimistic that the winter could be an average one in terms of amounts of snow.
Points of interest from the above list are that the seasonal global computer models are mostly suggesting the mobile, Atlantic dominated and mild winter with the UK Met Office model, the ECMWF model and Meteo France model, all in this mobile and milder camp.
The SSW's are an unknown factor and can completely change the weather pattern, so these will always need to be watched closely.
Finally, we come to the sun. We are currently in Solar Cycle 24 and in a solar minimum, meaning that sunspot activity has been non-existent at times this year. This is important and potentially really important, as winters with a solar minimum can see more in the way of high pressure at northern latitudes, which brings colder weather to Europe. This solar factor could be the joker in the pack this winter, if it overrides some of the factors listed above... and that is the big question...
Summary - a mild, Atlantic dominated winter for Europe, especially NW Europe is what some are expecting this year, however, the solar factor could play a very important role. If it does, then there is the chance of a period of deep cold developing for a time in Europe this winter if northern blocking takes hold.
An eye will be kept on these factors over the coming weeks, especially as the seasonal
models can and do change.
Next update expected tomorrow on the prospects for snowfall next week...