Weather 21/07/18

[TLouth7]

I am getting a peculiar effect on windy.com when I look at the rain forecast on Saturday afternoon around Harwich. When zoomed fairly far in it shows massive areas of thunderstorms off the coast, but these disappear upon zooming out.

Anyone got a good idea of what the weather might actually do?

https://www.windy.com/?rain,2018-07-21-15,51.968,1.488,11,m:e5Iagdk

 

[johnalison]

Passageweather is showing a band of light rain passing through from the north during the day but I don't know what this will amount to.

 

[TLouth7]

Hmmm,

this seems to be a bug as on Chrome the massive thunderstorm doesn't appear at all.

 

[ex-Gladys]

The Met Office weather warning for thunderstorms is from 1400-2359 Friday...

 

[franksingleton]

For short period - up to 18 or 24 hours around the U.K. it is best to use the Met Office app showing rain predictions or, more correctly, predictions of the radar image. Heavy rain in showery conditions especially, is always likely to be thundery. Particularly with gold fronts or occlusion, heavy rain may also be thundery.

Otherwise, look for heavy rain on NWP forecasts together with high CAPE values, http://weather.mailasail.com/Franks-Weather/Cape. Always remember that showers have a high degree of uncertainty in prediction of location. Always heed what forecasters actually say rather than any automatically generated worded text whether from unofficial sources such as MeteoConsult or official sources, Met Office, Meteo France etc.

 

[Old Bumbulum]

www.ventusky.com is the mutt's nuts for clarity.
It is optimised for phones and tablets.
Brilliant!

 

[franksingleton]

www.ventusky.com is the mutt's nuts for clarity.
It is optimised for phones and tablets.
Brilliant!

Thank you for that. Such services are springing up at a rate that I cannot keep up with. It gives output from several models. Some will like the presentation, others will not.

There is an error in their description of the DWD ICON model. This uses a 12-13 I’m grid worldwide not 7 km as they say. ICON is not the finest global grid. The GFS uses the same side grid. The U.K. and ECMWF both use 10 km. ICON does use 7 km over Europe - ICON-EU. That is a minor glitch but such statements emphasise that providers os such model information do not always understand the models.