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Cross Channel Weather The cross channel weather forecast is vital to a successful trip. It is necessary to consider not only the outbound trip but whether the weather will change to prevent a return trip on the same day. It is not uncommon for the weather to be completely different on opposite sides of the channel. Worse the VFR weather in the middle of the channel can be worse than on either side. Click here to find out why. During the day the weather will often change so that there can be cloud and storms over the land during the afternoon. By evening things may well calm down giving a window of opportunity.
Above: Clouds over the French Coast, ceiling was actually broken at 1500ft, quite OK but don't get trapped on top, IMC ratings are not valid in France. Much weather information is available on the internet and the links on this page should provide all you could possible need. The snag is that most GA airfields have neither a flight briefing unit nor the Internet. The most the GA pilot can expect is a MET form 214 and 215 hanging on a clip. Planning should therefore be done at home, but one needs to be careful, things can change during that hour drive to the airfield. Hazy Weather There are occasions, often during a heat-wave when one might expect a trip to France to be ideal, when it can in fact be quite hazardous unless one has instrument flying experience. In summer during periods of high pressure the visibility can be quite poor and over the sea with no reference there can be no horizon. If in doubt turn back. A useful trick if you feel confident enough is to climb on top of the haze. The inversion layer is often at about about 3000ft. Beware though sometimes the inversion can be higher than 5000ft and below it can feel like flying along in a vertical tube of fog. Flight planning Met is available from:
Met Office http://www.meto.gov.uk/
Meteo France http://www.meteo.fr/e_index.html Before leaving Home The odd thing is that the first task is to plan our return trip! Since a trip will often be for a day we need to plan to get home again. Many accidents happen as tired PPLs struggle home in worsening conditions after a day in France. Listen to London Information (124.6) on your airband receiver on a rainy Sunday evening to hear the difficulties people can find themselves in. When studying the METform 215 it is therefore necessary to note both the position of fronts and from their speed to estimate their time of arrival at the point of return. METform 415 (Continental weather) can also be consulted although the level of detail is lower. During our PPL training we will have been taught to use the Met form 214 and 215. This guide just adds the extras relevant to crossing the channel. The METform 215 is all we are likely to get once we are at the airfield so it is as well to be familiar with it.
Left METform 215, Right METform 415 The arrow drawn through the front or other weather feature gives its speed in Knots.
If the speed is 10 knots and it is 50 miles from your point of return then it will arrive in 5 hours time. 24 hour TAFFs are available for certain locations the most useful being Brize Norton (EGVN). Remember the cloudbase is quoted above airfield level.
18 hour French TAFFs are also available on the Met office web site. The TAFFs for Brest (LFRB) and Lille (LFQQ) should give a good picture.
The published cross channel forecast (Airmet) is not published until 7.30am Zulu time (1 hour after the UK met), so if planning a day out it may be published too late to be taken account of at the planning stage.
The general weather situation in France can be obtained from Meteo France but specialist aviation weather is available only to members of the French Aero club or to subscribers. The Meteo France weather forecast is in French so if in doubt click here for the Dodgy guide to Meteo France. Before Departure Now comes the crunch, we are at the strip or small airfield ready for departure and we need a quick met check at our destination. We can use the met office premium rate lines for TAFFs and METARs, but our mobile phones and most coin operated phones will not work with the premium rate phone lines. Furthermore the TAFFs and METARS can be up to 1 hour old so if we are waiting for fog to clear at Le-Touquet an hour can be a very long time to wait. The best solution is to use our mobile phone to call our destination. We can call the tower at our destination direct or use a whole range of free weather services.
En Route Once in the air we can use Volmet South 128.6 which will give us the UK weather which is useful if we have to divert back to the UK, but of very little use for conditions in France. Paris Radio 126.0 might be of use but none of the airfields for which METARs are broadcast are near the coast. If there is any doubt London information will provide the "actual" for your destination. this is a protracted affair which should only be used if there is a real view that the met may have changed. As one gets closer a call to the destination is often the easiest option. Getting Home Once in France we are stranded, with no internet and no premium rate phone lines. Mobile phones and call boxes just will not collect the fees payable to the Met Office premium rate lines. The variability of met information at the airfield is as patchy as it would be in the UK. At Calais they will get printed TAFFS and METARS in the Tower, while at Cherbourg there is sometimes a weather chart hanging in the office of the "Chambre du Commerce". Caen however has a Met office and I have used it. Look at the guide to Caen to see how to get to it and back to your aircraft afterwards. The French equivalent of the METform 214 and 215 is the 8063 and 8042. These are very different from their UK equivalent. 8064 Wind (METform 214 equivalent)
The wind vectors are shown graphically. The decode for wind speeds and velocity is given below:
The 8515 (METform 215 equivalent)
The 8515 decode is given below:
Altitudes on French charts are always expressed in the same way:
If all else fails the tower can get a METAR for your destination or you can call your destination direct. One last trick is to use the Southampton ATIS. This service was withdrawn in 2006, yet another example of sacrificing safety for commercial gain.
En Route Home Once in the air we can use Volmet South 128.6 which will give us the UK weather in quite sufficient detail to judge the weather at the destination. If there is any doubt London information will provide the "actual" for the destination. Diversion airfields along the UK coast are all at sea level, however most have high ground just in land, so I always select Lydd or Southampton rather than Shoreham or Goodwood. |
