Hail on Radar

[robb]

What size does hail have to be to show up on the precipitation type radar?  I've never seen hail shown on radar images even during a hailstorm that left a covering that was close on an inch in depth. 

[Paul]

Hail is something we've historically struggled to pick up on the precip type detection, and is something we're looking to improve over the course of this year. But for now it'll show very rarely I'm afraid. 

[robb]

Cheers Paul, thanks for the reply.

[William Grimsley]

Yeah, even snow shows as rain on the precipitation type...

Edited March 4, 2016 by William Grimsley

[Paul]

It's not 100% William, but in most cases the precip type is very accurate - we use ground reports to verify it. 

[William Grimsley]

On 3/4/2016 at 11:56 AM, Paul said:

It's not 100% William, but in most cases the precip type is very accurate - we use ground reports to verify it. 

Fair play, but it was inaccurate for lots of places over the past 2 days, it mustn't be taking local intensities/temperature's into consideration.

[Paul]

It certainly is William, and funnily enough the feedback we've been getting it just how accurate it's been! Obviously not everywhere will be bang on every time, but that's the nature of the beast - if the UK radar network was doppler based it would be a much simpler process to detect what's falling but as it isn't we have to use alternate techniques. 

[chionomaniac]

I have to say that I have found the netweather precipitation type radar remarkably accurate over the last few years as well. Considering as well when it is raining in one place and snowing 10 miles down the road - it even picks this up. I am actually surprised at how accurate it has generally been.

Edited March 5, 2016 by chionomaniac

[Evening thunder]

I find it ok, and quite good for a guide and general view across the country, but not to be taken too literally on the local detail.

It did think this was all rain yesterday though:

Can't be anything other than honest and say for marginal situations (when you aren't sure yourself what the precip type is), it can often be a bit out here. But I don't know of a better version and guess any algorithm will get it wrong sometimes. It probably does well considering it's not actual detection, and have noticed it showing the effects of elevation quite well.

Edit: though to be fair there hasn't been too many opportunities to test it this winter lol, so maybe it was 'unlucky' recently, and has been improved further from what I remember

Just as long as it's not called 'detection' like I've seen sometimes, I don't mind.

Edited March 5, 2016 by Evening thunder

[William Grimsley]

On 3/5/2016 at 8:24 PM, Evening thunder said:

I find it ok, and quite good for a guide and general view across the country, but not to be taken too literally on the local detail.

It did think this was all rain yesterday though:

Can't be anything other than honest and say for marginal situations (when you aren't sure yourself what the precip type is), it can often be a bit out here. But I don't know of a better version and guess any algorithm will get it wrong sometimes. It probably does well considering it's not actual detection, and have noticed it showing the effects of elevation quite well.

Edit: though to be fair there hasn't been too many opportunities to test it this winter lol, so maybe it was 'unlucky' recently, and has been improved further from what I remember

Just as long as it's not called 'detection' like I've seen sometimes, I don't mind.

True, I totally agree with you. But, I think this year hopefully the radar should be improved.