"Clear outside" very different results on phone and PC.

[Starwatcher2001]

Checking the weather for tonight on the 'Clear Outside' app on Android, teasingly shows a good chance of observing. I'm rather doubtful looking at the weather forecast from the BBC, so I checked the PC and the forecasts are totally different.

I've got them set for the same location, refreshed both, removed and re-installed the android app...

any idea anyone?

 

EDIT: Ah... worked it out. The PC is showing Saturday's forecast. I must have scrolled the display or something.

 

 

 

 

 

Edited October 1, 2021 by Starwatcher2001

[Dazzyt66]

You cant really rely on anything but your eyes. I tend to use at least 3 different weather apps just to get a kind of idea. IMO I've always found Clear Outside to be pretty inaccurate if the weather is 'changeable' (I've had all reds on CO and yet its been perfectly clear outside when I've looked). They all are, after all, a forecast. My advice would be use several to get a general idea of whether its going to be suitable or not (clear, semi clear, not) and then have a look as it gets darker. 

Sorry, I know that doesn't help much but the weather (particularly in the UK) rarely does what anyone expects 🤔

[globular]

1 hour ago, Starwatcher2001 said:

EDIT: Ah... worked it out. The PC is showing Saturday's forecast. I must have scrolled the display or something.

You also have different coordinates on PC verses Phone… (54.55,-1.30) verses (54.57,-1.33)…. and this will lead to some differences too.

[Starwatcher2001]

16 minutes ago, globular said:

You also have different coordinates on PC verses Phone

Well spotted, thanks. But those fractions only work out to be less than a couple of miles, which I don't think is significant where the weather is concerned.

[Dave scutt]

Thanks I didn't know about the clear outside appo

[SuburbanMak]

Within a short-range window I have found the Met Office Cloud Cover forecast to be the most reliable/ least unreliable...  https://www.metoffice.gov.uk/public/weather/uk-cloud-cover-forecast/#?tab=map&map=Cloud&zoom=5&lon=-4.00&lat=55.74&fcTime=1633035600

Often take a look at the Jetstream forecast especially if CO/Met Office showing as clear, help me make the all important decision if its worth putting scopes in the car or just doing something from the back garden    https://www.netweather.tv/charts-and-data/jetstream

[Zermelo]

There's an ongoing comparison of some forecasting sources here:

 

[Second Time Around]

I'll be posting the September results very shortly.

[Jonk]

This very issue is the main driver for me using an allsky camera. I recently saw the BBC weather and most if not all sources say 100% cloud coverage - outside, I could see stars and no clouds. The allsky showed up a bit of murk, but in the main this didn't prevent any imaging. And this was for the first 3-4 hours of darkeness. All forecasts were wrong.

I also post monthly realtime results for those interested ->

For the forecasts, I use CO, Ventusky, Metcheck, Darksky and Raintoday - together you get a good idea, but I agree with a post above, you cannot beat using your own eyes. (Or allsky!)

[Paul M]

It's only a forecast if a forecaster, professional meteorologist, has produced it!

What many/most/all the general apps do is spit our raw model data. A graphical display of probability. 

[Pixies]

The website can show odd dates, depending on when you view it and how you have it set up - centred on current time, midday or midnight. In your pic, it says Friday 1st, but the 'clock' marker is at 7am the following morning. Basically, you are seeing the previous night.

I find it best to set it centred on midday, when it's the morning  Then centre it on midnight when PM.

[ONIKKINEN]

Neither seem to give any kind of usable forecasts for me, clear outside shows green and 0% cloud cover when in fact there isn't a single star anywhere in the sky. Sometimes its the other way around, should be cloudy but its mostly clear. Cant really trust the service at all.

[Stickey]

On 01/10/2021 at 09:15, Starwatcher2001 said:

Well spotted, thanks. But those fractions only work out to be less than a couple of miles, which I don't think is significant where the weather is concerned.

Not sure that's totally true about miles not mattering. I've often experienced rain-soaked ground vs. completely dry within 2 miles. I was up in the Peak District a couple of days ago and was looking over the Cheshire Plain at the approaching weather. I could see separate rain showers about a mile or 2 apart. 

Like others, I use multiple weather apps for early warning but none of them are that reliable. In the end, I also use my eyes, the clouds, the direction of the wind and radar to tell me whether I've got enough time that makes it worth setting up.

JMO

[Starwatcher2001]

I agree Stickey, I've seen that phenomena too. It's the prediction of weather that's never going to be accurate within a few miles.

As it happened, I managed to get a good couple of hours under the stars last night. The skies weren't perfect here, but I had a blast anyway and saw a good 15-20 objects across the sky - a thoroughly good antidote to a naff week in the office.

[Jonk]

7 hours ago, Stickey said:

I could see separate rain showers about a mile or 2 apart. 

I've been stood in a field with heavy rain about 100 yards away and stayed bone dry. It was odd!

[Paul M]

I don't know what resolution (grid size) the model data is that these apps use but I guess it's in the Km range not the m range!

My advice would be to use a combination of the human presented Met O or BBC forecasts and satellite/radar imagery. I spend hours watching forecasts and remote imagery and have read a few meteorology text books. I like to think I have as a good a chance as anyone of getting it right. But still I regularly get caught out or disappointed.

I'll never forgive the Beeb for making the politically motivated move from the Met O but I still hold their weather forecasts in very high regard, along with their presenting meteorologists.