Jump to content

Archived

This topic is now archived and is closed to further replies.

CatchMyDrift

Freezing Rain

Recommended Posts

I've been a wee bit annoyed today that despite a dew point of -6C and an air temp of -5C we actually had heavy rain this morning...

Can someone please explain the mechanics of freezing rain to me and the wider NW audience.

Share this post


Link to post
Share on other sites

In a basic explanation, freezing rain occurs when the surface temperatures are very cold, cold enough to support snow, but the upper air (850's) is not.

It falls as rain from the clouds but freezes on impact with the ground because the air and ground is so cold.

Share this post


Link to post
Share on other sites

Yes, that's it in a nutshell. There's a large area of the country sitting in a relatively shallow pool of very cold air at the moment, compare the minimum here last night, of -0.9c, with that in the Trent valley at -9c.

That very cold air probably extends only up to around 100m or so above the ground and once you get on to the hill tops, in the free atmosphere, the temperature is close to what would be experienced at lower levels with the same 850 hpa temperatures if the air was well mixed.

Share this post


Link to post
Share on other sites

I've been a wee bit annoyed today that despite a dew point of -6C and an air temp of -5C we actually had heavy rain this morning...

Can someone please explain the mechanics of freezing rain to me and the wider NW audience.

If the rain continued and the temps stayed low I bet everything looks very nice even though it's very hazardous.

here's one example I found on the internet

post-2404-0-17797500-1293362720_thumb.jp

Share this post


Link to post
Share on other sites

In a basic explanation, freezing rain occurs when the surface temperatures are very cold, cold enough to support snow, but the upper air (850's) is not.

It falls as rain from the clouds but freezes on impact with the ground because the air and ground is so cold.

All rain in the UK starts as snow unless it's an exceptional situation. It falls as snow from the clouds, melts to rain on the way down, then freezes in the shallow layer of sub zero air near the surface, or on the surface.

Share this post


Link to post
Share on other sites

Yes, that's it in a nutshell. There's a large area of the country sitting in a relatively shallow pool of very cold air at the moment, compare the minimum here last night, of -0.9c, with that in the Trent valley at -9c.

That very cold air probably extends only up to around 100m or so above the ground and once you get on to the hill tops, in the free atmosphere, the temperature is close to what would be experienced at lower levels with the same 850 hpa temperatures if the air was well mixed.

I knew that...I was just crying like a baby since the Christmas Day snow failed :lol:

It just shows you that any idea of embedded cold is pretty much nonsense :unknw: :lol:

If the rain continued and the temps stayed low I bet everything looks very nice even though it's very hazardous.

here's one example I found on the internet

I will post a pic of my black privet hedge at the weekend, the "black rain" on Christmas Day has left every non-evergreen plant orange/black. Very weird.

Share this post


Link to post
Share on other sites

I had a spell of freezing rain on 9th Dec this year, started off as snow, then the temp was -3.1C and was raining, slippiest conditions ive known, people were slipping and sliding all over the place

Share this post


Link to post
Share on other sites

All rain in the UK starts as snow unless it's an exceptional situation. It falls as snow from the clouds, melts to rain on the way down, then freezes in the shallow layer of sub zero air near the surface, or on the surface.

I'm no expert but shouldn't that be the rain supercools? The reason for the sudden freezing.

Share this post


Link to post
Share on other sites

×
×
  • Create New...