Hows that yellow warning for heavy rain doing?

Estimated accumulations from weather radar
0200-1255 UTC 19 October 2020
Filtered: Coloured pixels >=25mm Grey Pixels<25mm

The yellow warning warning for heavy rain from the Met Office has only been running for eleven hours or so, and it’s already quite apparent that the bulk of the rain which has fallen is much further north than they anticipated. I mentioned that the area in the warning they issued yesterday didn’t extend far enough north (when compared to the latest ECMWF forecast) in a blog that I posted yesterday, a mistake they have made a number of times recently across this part of Scotland. I also noticed that in the warning text they had forgotten to include a forecast accumulations for low ground. Fast forward twenty four hours and guess what?

The warning area has been extended north towards the Western Isles and pulled out of South Lanarkshire and West Lothian.
Spells of rain, heavy at times, will persist through most of Monday before clearing on Tuesday morning. 20-40mm of rain will fall quite widely, while 50-75 mm is expected over the more mountainous areas. Over a few mountains, most likely in Argyll, as much as 75-100 mm of rain may fall.


I could do better working from my back bedroom

As you can see they addressed both of my concerns regarding yesterday’s warning. They now mention a specific accumulation for low ground of 20 to 40 mm, and at the same time extending the warning area much further northward. I have no idea why the warning for Northern Ireland of 20 to 30 mm (does this really need a warning?) is deemed more likely to occur in the warnings matrix than the one for Scotland, especially in light of the latest ECMWF accumulations forecast, perhaps it’s because there is some kind of understanding they have with Met Eireann who seem to have gone to town with their warnings of heavy rain.

Courtesy of
Courtesy of UKMO
Courtesy of UKMO
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