Cloud levels

[markpodbery]

I am sure this has been asked a million times and there is no answer, but I can't seem to find anything much after a search!

Is there anyway or website that shows the thickness of the cloud levels to be able to climb above?

Thanks

Mark

[Merlin83b]

The 215 shows tops if below FL100, which might be what you need. If not you should go and look at Peter Holy's website - lots of information on assessing cloudy weather there.

[Irv Lee]

one of the most misunderstood features of Metform 215 is the cloud notation. Given
BKN 020-040/070-090 and asked - are you likely to be in cloud at 6000'? - most (>90%?) pilots I meet will wrongly say no, that is between 2 layers

[rats404]

The 2012 version of "Get Met" has a number of explanatory notes.

http://www.metoffice.gov.uk/media/pdf/e ... 012_V2.pdf

Page 15 covers the 215. I have to say though, that it could have been written more clearly, with a worked example of a 215.

[Jwscud]

I wouldn't rely on cloud tops in the 215. I look fairly regularly at this time of year trying to find acceptable VMC gaps between layers to avoid icing conditions, but have regularly found even the forecast ranges a bit shaky. Don't rely on finding VMC - always have a backup plan, especially when the freezing level is below MSA.

[GrahamB]

The GFS Skew-T diagrams available here can be helpful in anticipating where tops and layers might exist, once you learn how to interpret them. There's plenty on the web that explains them.

You get to them via 'Weather Maps > Expert Charts' then top right 'GFS' under 'Soundings'

[Irv Lee]

The 2012 version of "Get Met" has a number of explanatory notes.

http://www.metoffice.gov.uk/media/pdf/e ... 012_V2.pdf

Page 15 covers the 215. I have to say though, that it could have been written more clearly, with a worked example of a 215.

Yes but even if they knew where to look, they wouldn't, as they are absolutely sure they know what it means, so 'no need'

[Pugh Pugh]

OK Irv, on the basis that "there are no stupid questions, only stupid answers", and in the hope that you will therefore be gentle with me, could you please explain your example so that I may check my understanding of it now rather than at FL60 in icing cloud (or not!)

[Irv Lee]

just 'parse' around the '/' - left of it is a base or base range, right of it is the top or top range - so BKN 020-040/070-090 would not be two layers with a gap in between, it would be a base between 2000' and 4000', and tops would be between 7000' and 9000'. They don't have to have 2 bases or two tops, levels like 002/015 is sometimes seen when radiation fog is supposed to lift into low stratus, meaning 200' base, 1500' tops - the key is to know that the '/' divides base and top - but I'm struggling to remember anyone knowing that 'straight off'

[Cumulo-nimbus]

Bluddy obvious, ain't it. eh? Anyhow, that's how I've always read it.

[Pugh Pugh]

Thanks Irv. My understanding was correct, but your comment of 90% of pilots not necessarily understanding the "bluddy obvious" (thanks Cu-Nim, not) introduced an element of doubt. Hopefully you've also cleared that up for others who may have had the same doubts, but who were reluctant to admit it because of patronising and unhelpful comments. Cheers.

[smithgd]

The met office F215 form has a user guide on their web site (including a worked example):

http://www.metoffice.gov.uk/aviation/ga-briefing-services/briefing-charts-details

[DavidC]

Anyone know if the GFS Skew-T diagrams mentioned above will continue to be available for Filton, now that the airport has closed?

[low&slow]

No reason why not, it's just a forecast for a particular lat/long & not associated with the airfield.

There's a better tool at this website. Select your date & time & the SkewT radio button under Info Popup & then right click on your location. You can see forecast cloud amount & heights on the left hand y-axis.