An overall analysis of the weather situation
To be relevant when analysing a day's flying, whether you're flying locally, cross country, tandem paragliding or an instructor with his students, it's important to observe the overall weather situation. A high-pressure or pseudo-depression situation is the first thing to determine, then depending on the position of our zone in relation to these air masses, we have several criteria to take into consideration. To do this, we use windyThe air mass and flow diagrams are very practical and easy to read. Remember that you can tell the difference between a high-pressure system and a low-pressure system by their pressure: if it is higher than 1013Hpa, then we are in a high-pressure system (high-pressure system) and if it is lower, then we are in a low-pressure system (low-pressure system). We also know that a flow moves from the anticyclone towards the depression, it is called weather wind, because of the Coriolis effect it is deviated to the right in the northern hemisphere and left in the southern hemisphere. Once we have determined the direction of the weather wind, we can get an idea of its strength by observing the pressure difference between the two air masses on either side of the zone in question. If there is a lot of difference, the isobars are tightened, so we have strong winds, and if there is little difference, the isobars are relaxed, so we have little wind. Let's not forget that the effect of relief also influences wind strength (Rhône valley).
Take-off from Jerusalem in a two-seater paraglider
On the scale of a mountain range or a valley!
Now that we've got you down to earth, let's scale things down a little to see what's happening on our favourite summits. I'm using meteoblue interactive map to analyse 3 criteria : the instability of the air mass, the wind at different altitudes and the cloud cover (possible risk of thunderstorms, For the instability of the air mass there is the geopotential which indicates the maximum ceilings depending on the sector and there is our good old emagram with its state curve which gives you a survey of the air mass (dry adiabatic) and its blue curve which indicates the dew point depending on the altitude (saturated adiabatic): at which altitude the air particle reaches saturation and forms the cloud! These indications are important for determining the character of thermals and also breezes and the height of clouds and how they change over the course of the day. This plays a vital role in the choice of take-off and the day's flight plan. I look first at 850hpa (1500m) then 700hpa (2000m) then 3000m. This will also help me choose the take-off and the timing, bearing in mind that at Gréolieres we have 3 main take-offs which are not at the same altitude and do not necessarily all accept the same wind values and directions. Then comes the cloud cover, which will influence the character of the thermals, of course, but will also help us choose the right take-off. Finally, I make the same analysis in comparison with Aeroweb (you need to create an account, it's free) which uses the arôme model from Météo-France while météo-blue uses Icon, an average of several models. Choosing the right model for weather analysis is vital, as some have two-day forecasts while others have three or even four-day forecasts, my favourites and the most reliable from my little experience in the Alpes-Maritimes are Icon and Arome. You also need to be able to interpret a westerly wind from the south-west or north-west depending on where you are located in the mountains. Of course, above the mountains you'll have a very marked direction but the relief channels the breezes and also the weather winds up to certain altitudes. The easterly wind brings us the humidity from the Pau plain and is often synonymous with a fine morning of free flight followed by very cloudy skies (good materialization of thermals) or even spreading which cuts the convection at the end of the day.
From analysis to live observation of weather beacons
We're lucky enough to be able to use weather beacons linked directly to our smartphones. This technology allows us to be more responsive, relevant and efficient in our practice. Optimisation is the key, and what's really interesting is being able to observe changes in conditions live. To do this, I use Spotair, a great site dedicated to nature sports that depend heavily on aerological and meteorological conditions: paragliding, hang-gliding, speed-riding, kitesurfing. SpotAiR brings together a number of sources of 'real time' data from the ffvl or piou-piou beacons, as well as webcams, allowing you to assess the conditions. It also allows you to see the wind history with directions and strengths over the day, which is very interesting. On the Cheiron, you need to interpret these values carefully, as the averages and gusts as well as the wind directions are specific to each take-off and need to be interpreted individually. For example, an average of 16 and a gust of 25 at take-off from the 300 are still acceptable for a seasoned and very agile pilot. However, if this same value is indicated on the Cheiron commet, then it's far too strong to take off from the Jerusalem, as it's in a small pass and the compression means we can easily add 5 km/h. As for the wind direction, from South-East to South-West for the Jerusalem and South-South-East for the 700, be careful with West-South-West you are downwind of the small dome on the right of the take-off. The take-off of the 300 is south facing the Gorges du Loup and accepts south-westerly and south-easterly winds. On unstable days, it can climb quite quickly in the breeze, but beware of westerly winds that prevent you from returning to the ground on landing.
The seasons and associated weather conditions for paragliding
Of course, typical situations can be associated with the seasons, and everyone has noticed that in winter the aerological conditions are calmer and that in spring the flying conditions improve! But be warned, this is only a general rule, and more and more spring conditions are settling in for a few days in the heart of winter in the south of France. And yes, the Alpes-Maritimes often suffer from a lack of snow and benefit from generous sunshine, all this combined with a small cold drop that instabilises the air mass and we have a lovely cocktail for free flight!
We all agree that this analysis should of course be correlated with your technical level and will determine whether the conditions in the air are good for you or not. If the conditions are a little strong, you may decide to take off earlier in the morning to take advantage of the first thermals and land when the conditions are still acceptable for you! It's important to remember that most landings in the Alpes-Maritimes are fairly technical and turbulent in mid-day thermal conditions in spring, summer and early autumn. What's more, spring days often end in thunderstorms, with cumuloniform clouds that develop strongly and can influence the air mass for dozens of kilometres around. Heavy rain, hailstorms and strong winds are to be feared. Let's not forget the strong anticyclonic conditions with marked stability, where the weather is fine and warm but in the air, due to the stable nature of the air mass, which is generally dry, everything is pressed to the ground and you need overheating to get the thermals off the ground. Once they have taken off, most of them will be unusable because they are small and very nasty. You can use meteocial to determine whether the air mass is stable or unstable, and you even have the wind associated with different altitudes
Of course, typical situations can be associated with the seasons, and everyone has noticed that in winter the aerological conditions are calmer and that in spring the flying conditions improve! But be warned, this is only a general rule, and more and more spring conditions are settling in for a few days in the heart of winter in the south of France. And yes, the Alpes-Maritimes often suffer from a lack of snow and benefit from generous sunshine, all this combined with a small cold drop that instabilises the air mass and we have a lovely cocktail for free flight!
We all agree that this analysis should of course be correlated with your technical level and will determine whether the conditions in the air are good for you or not. If the conditions are a little strong, you may decide to take off earlier in the morning to take advantage of the first thermals and land when the conditions are still acceptable for you! It's important to remember that most landings in the Alpes-Maritimes are fairly technical and turbulent in mid-day thermal conditions in spring, summer and early autumn. What's more, spring days often end in thunderstorms, with cumuloniform clouds that develop strongly and can influence the air mass for dozens of kilometres around. Heavy rain, hailstorms and strong winds are to be feared. Let's not forget the strong anticyclonic conditions with marked stability, where the weather is fine and warm but in the air, due to the stable nature of the air mass, which is generally dry, everything is pressed to the ground and you need overheating to get the thermals off the ground. Once they have taken off, most of them will be unusable because they are small and very nasty. You can use meteocial to determine whether the air mass is stable or unstable, and you even have the wind associated with different altitudes.
