Primarily for general aviation discussion, but other aviation topics are also welcome.
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By George
FLYER Club Member  FLYER Club Member
#1862337
Have a nice little overnighter planned for Friday and Saturday, Shobdon to Bembridge for a family visit. I particularly want to make this trip on the days planned as alternative is a long drive and expensive ferry trip. Yeah, it’s cheaper to fly to the IoW innit.

However.

W/x varies from sunshine and showers 30-45% just on the BBC app at the moment.

Sky Demon and TAFs will be a big help on the day of course. Shower probability means you are 70-55% likely to not run into one and can skirt around of course. I’d just like to know a little further in advance how likely it’ll be flyable.

I’d welcome the views of what the team thinks. Oh, and I seem to recall from way back that Simon K at Weather School would offer a personalised forecast for a small fee?

Any recommendations for reliable weather apps and planning aids welcome too.
By TopCat
FLYER Club Member  FLYER Club Member
#1862341
Do you mean next weekend, ie 6,7,8 August?

If so, then it's almost impossible to say, this far out.

Mostly, the best you can do is look at the long range surface pressure charts, such as these, to see what the air masses are likely to do.

There's windy.com, of course, and rasp.stratus.org.uk/, but a week ahead it's still very uncertain.

Unless there's a large area of high pressure forecast, prediction is very hard - fronts can move slower or quicker than forecast, making a huge difference to the outcome on a particular day, and areas of low pressure, as we've had over the last few days, can give unpredictable patterns or bands of showers, some of which can be heavy and prolonged, or coalesce into wider areas of rain.

And even if the pressure is high, you can get poor visibility and fog.

No crystal ball a week ahead, I'm afraid. Personally I wouldn't pay money for a forecast.
Last edited by TopCat on Sun Aug 01, 2021 8:34 am, edited 1 time in total.
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By johnm
FLYER Club Member  FLYER Club Member
#1862342
If you subscribe to Simon you can get a 2 week look ahead that will give you a clue. You won’t really know until Thursday and only then if weather is relatively stable
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By Irv Lee
FLYER Club Member  FLYER Club Member
#1862352
At this range, I would be very worried if the BBC said your two days were the only good couple of days.
And remember the Aviation Fly-in Law, the chance of good weather is inversely proportional to effort expended in early preparation
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By mr spog
FLYER Club Member  FLYER Club Member
#1862437
The BBC weather forecast is c**p in my opinion.
It appears to be very specific both in terms of time and location, even over a week ahead. However, if you recheck it daily leading up to your planned flight, you will usually find that it constantly changes, and it's basically a waste of time this far in advance.
Apparently, they don't even use the supercomputer that the met office use, as they have subscribed to another service. (That was just hearsay, and I can't confirm it.)
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By Rob P
#1862439
mr spog wrote:Apparently, they don't even use the supercomputer that the met office use, as they have subscribed to another service. (That was just hearsay, and I can't confirm it.)


MeteoGroup.

Rob P
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By IainD
#1862443
mr spog wrote:The BBC weather forecast is c**p in my opinion.
It appears to be very specific both in terms of time and location, even over a week ahead. However, if you recheck it daily leading up to your planned flight, you will usually find that it constantly changes, and it's basically a waste of time this far in advance.
Apparently, they don't even use the supercomputer that the met office use, as they have subscribed to another service. (That was just hearsay, and I can't confirm it.)


Auto forecast is based on raw ECM model output so is volatile as no human input and as much use as a chocolate teapot.
By Boxkite
#1862457
mr spog wrote:The BBC weather forecast is c**p in my opinion.
It appears to be very specific both in terms of time and location, even over a week ahead. However, if you recheck it daily leading up to your planned flight, you will usually find that it constantly changes, and it's basically a waste of time this far in advance.
Apparently, they don't even use the supercomputer that the met office use, as they have subscribed to another service. (That was just hearsay, and I can't confirm it.)

Agree, they seem to just look out of the window and correct the forecast for the next 12 hours. Even their 'Weather Warning' feature often doesn't match their hourly forecast. They can be warning of high winds for a period within the next 48 hours but when you look at the hourly forecast there's nothing unusual to be seen.
By proteus
#1862460
As mentioned many times above, with anything other than a settled high, looking that far forwards is crystal ball territory. I quite like looking at the expert charts on weatheronline.co.uk

It depends what sort of weather you're comfortable with and what the aircraft capabilities are, but with the present guess I'd say it could be possible. but all subject to change. best to look more seriously at it on Weds / Thurs.
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By Gasbag
#1862463
I do like Irv’s Aviation law being inverse.
I use the inverse laws for TAFS as in Women’s lingerie and Nouvelle Cuisine.
The more expensive the lingerie, the less material you get;
The more expensive the dish, the less food you get;
The more written on a TAF, the less chance of going flying you’ve got………
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By George
FLYER Club Member  FLYER Club Member
#1862527
TopCat wrote:Mostly, the best you can do is look at the long range surface pressure charts, such as these, to see what the air masses are likely to do.

There's windy.com, of course, and rasp.stratus.org.uk/, but a week ahead it's still very uncertain.



Weathercharts made my eyes hurt a bit but that Windy.com one is brilliant for an overall look see what is going on!

Ta.
By TopCat
FLYER Club Member  FLYER Club Member
#1862531
George wrote:
TopCat wrote:Mostly, the best you can do is look at the long range surface pressure charts, such as these, to see what the air masses are likely to do.

There's windy.com, of course, and rasp.stratus.org.uk/, but a week ahead it's still very uncertain.


Weathercharts made my eyes hurt a bit but that Windy.com one is brilliant for an overall look see what is going on!

It very much is, but unless I've missed something, it doesn't show the weather fronts. Understanding frontal behaviour is absolutely essential knowledge for any pilot, so neglect them at your peril.