Weather Briefings
Thread Starter
Joined: Aug 2010
Posts: 2
Likes: 0
From: cranfield
Weather Briefings
Hello,
I was wondering what kind of weather briefing you guys obtain before embarking on a cross-country VFR flight?? What stuff do you look at? Can't really find a structured approach in the books..
Cheers!
Marie
I was wondering what kind of weather briefing you guys obtain before embarking on a cross-country VFR flight?? What stuff do you look at? Can't really find a structured approach in the books..
Cheers!
Marie
Joined: Nov 2007
Posts: 270
Likes: 1
From: Near the Mountains of Sussex
Register with Met Office.......... use the F215 and Airmet,
Met Office: GA briefing services
Metars here........ www.TheHangar.co.uk - METARs in Plain English
Overall situation here........ Wind Map - Britain Observations and SkyLinkWeather Aviation - Latest Weather for London Stansted
Good site with lots of links.........weather+soaring
Fill yer Boots !
Met Office: GA briefing services
Metars here........ www.TheHangar.co.uk - METARs in Plain English
Overall situation here........ Wind Map - Britain Observations and SkyLinkWeather Aviation - Latest Weather for London Stansted
Good site with lots of links.........weather+soaring
Fill yer Boots !
Joined: Jun 2003
Posts: 13,787
Likes: 0
From: EuroGA.org
Everything is on the internet now.
A reasonable safe approach for a VFR flight is
1) get the MSLP charts (available up to 5 days ahead) and if there are other people involved then knock the plan on the head if there is a major frontal system forecast. Otherwise, never cancel a flight on the basis of a forecast
Forecasters throw in everything including the kitchen sink otherwise 10,000 old ladies phone them up and moan.
2) On the day, before the flight, get the TAFs/METARs for the two ends, the alternate(s), and airfields along the route, and scrap the flight if anywhere along the route the cloudbase is forecast (or actually) below 1500ft, or visibility below 8km (or 3km if radio navigating e.g. GPS) 2hrs before to 2hrs after your ETA there. Remember taf/metar cloudbases are above the airfield elevation. Otherwise you GO.
3k vis will be either haze, or heavy rain which itself brings hazards e.g. flying underneath a CB. But the latter will be evident on the MSLP, and in the TAFs as e.g. PROB30 TEMPO +TSRA etc.
Avoiding fronts is the simplest way to have an easy life.
The above is for flying below clouds. VFR on top requires different data, and is more complex because one is often up against airspace. But this is a great method for foreign touring.
A reasonable safe approach for a VFR flight is
1) get the MSLP charts (available up to 5 days ahead) and if there are other people involved then knock the plan on the head if there is a major frontal system forecast. Otherwise, never cancel a flight on the basis of a forecast
Forecasters throw in everything including the kitchen sink otherwise 10,000 old ladies phone them up and moan.2) On the day, before the flight, get the TAFs/METARs for the two ends, the alternate(s), and airfields along the route, and scrap the flight if anywhere along the route the cloudbase is forecast (or actually) below 1500ft, or visibility below 8km (or 3km if radio navigating e.g. GPS) 2hrs before to 2hrs after your ETA there. Remember taf/metar cloudbases are above the airfield elevation. Otherwise you GO.
3k vis will be either haze, or heavy rain which itself brings hazards e.g. flying underneath a CB. But the latter will be evident on the MSLP, and in the TAFs as e.g. PROB30 TEMPO +TSRA etc.
Avoiding fronts is the simplest way to have an easy life.
The above is for flying below clouds. VFR on top requires different data, and is more complex because one is often up against airspace. But this is a great method for foreign touring.
Joined: May 2001
Posts: 4,631
Likes: 0
From: UK
Joined: Jun 2003
Posts: 13,787
Likes: 0
From: EuroGA.org
Yes wind of course, sorry... but it doesn't matter so much enroute, except for range purposes. And then we get onto how to accurately establish fuel flow, etc.....
MSLP charts are mean sea level pressure charts e.g. these
That is not the best site; like most free sites it presents charts pulled off various other sites and often they are not the latest available. I use Avbrief for a good collection of stuff, all in one place and reasonably well organised.
MSLPs exist in various forms. The above ones come from UK Met Office data, and are among the very few things which the UKMO releases for free. If you want a far greater range of free weather you have to go to the U.S.-run GFS system, and most weather websites which produce fancier presentations derive it from GFS e.g. this (the 2nd row down is the most useful for VFR).
MSLP charts are mean sea level pressure charts e.g. these
That is not the best site; like most free sites it presents charts pulled off various other sites and often they are not the latest available. I use Avbrief for a good collection of stuff, all in one place and reasonably well organised.
MSLPs exist in various forms. The above ones come from UK Met Office data, and are among the very few things which the UKMO releases for free. If you want a far greater range of free weather you have to go to the U.S.-run GFS system, and most weather websites which produce fancier presentations derive it from GFS e.g. this (the 2nd row down is the most useful for VFR).
Joined: Nov 2000
Posts: 3,443
Likes: 1
From: Cambridge, England, EU
Some of the time the area forecast could mean anything, the TAF says you can't fly, the METAR says it was fine half an hour ago. So, you can deduce nothing from the online weather sources (TAFs are often significantly worse than what actually happens ... but only often, not always).
Listening to the radio at home sometimes helps - if you can hear lots of students flying solo it can't be that bad; if the radio is completely silent apart from passing multi-engine IFR traffic talking about ice it's maybe not such a good day.
On some days it comes down to driving to the airport and looking out the window (where I live it's the nearest place I can go to see in a straight line at ground level for several miles in order to judge the visibility). On the most marginal days you then chat to people who've just landed (this is particularly the case on days when the TAF claims G35 and you find that actually there's a lightish breeze).
As IO540 says, if you always cancel a flight just because the forecast doesn't guarantee it's going to be flyable then you will hardly ever fly.
I always warn my passengers that there's a 50% chance of cancellation in summer, 75% in winter, and to expect me to cancel after we've all arrived at the airport. In the most extreme case, I had to fly one circuit with an instructor for club currency before going up with my passengers, and it was during this circuit that we decided that the weather really was crap after all, so on landing I told the passengers to go home.
Listening to the radio at home sometimes helps - if you can hear lots of students flying solo it can't be that bad; if the radio is completely silent apart from passing multi-engine IFR traffic talking about ice it's maybe not such a good day.
On some days it comes down to driving to the airport and looking out the window (where I live it's the nearest place I can go to see in a straight line at ground level for several miles in order to judge the visibility). On the most marginal days you then chat to people who've just landed (this is particularly the case on days when the TAF claims G35 and you find that actually there's a lightish breeze).
As IO540 says, if you always cancel a flight just because the forecast doesn't guarantee it's going to be flyable then you will hardly ever fly.
I always warn my passengers that there's a 50% chance of cancellation in summer, 75% in winter, and to expect me to cancel after we've all arrived at the airport. In the most extreme case, I had to fly one circuit with an instructor for club currency before going up with my passengers, and it was during this circuit that we decided that the weather really was crap after all, so on landing I told the passengers to go home.
Joined: Jun 2003
Posts: 13,787
Likes: 0
From: EuroGA.org
The thing is that no matter how you wrap it up, truly 100% legal VFR flight below the cloudbase, for long distances (say 200nm plus), is never going to be easy (in terms of being able to get airborne with confidence) unless you pick good weather over a large area i.e. a high pressure zone.
Joined: Jul 2006
Posts: 59
Likes: 0
From: Bristol'ish
Orbifly is a good one.
See menus at the top and home in on your area and chart type.
Does Europe.
Here's a view homed in on the UK.
Hover over the point on the map.
Orbifly Met'map
See menus at the top and home in on your area and chart type.
Does Europe.
Here's a view homed in on the UK.
Hover over the point on the map.
Orbifly Met'map
Joined: Jul 2004
Posts: 209
Likes: 0
From: Liverpool
Several airfields have webcams e.g. Wellesbourne Mountford. If they have one or there is one nearby I always have a look to see what the weather is really like. The same applies for en route waypoints.
