Spring 2017 - General Discussion

sryanbruen

Billcarson wrote: »

Lovely charts if its interesting weather your after. The last time we had any properly interesting weather imo was the same time last year aswell with similar charts.

Get out of here :rolleyes:, it's April. NO COLD, NO SNOW. Me want warm, hot, sunny weather from now 'til October.

Billcarson

sryanbruen wrote: »

Get out of here :rolleyes:, it's April. NO COLD, NO SNOW. Me want warm, hot, sunny weather from now 'til October.

Would lead to some great convection. Had some lovely big hail showers in a similar set up last yr,9/10c in the sunshine between the showers,down to around 4c in the showers. Temporary hail coverings .I love those sort of days this time of yr.

Thought the late april cold snap last yr was the most interesting weather we had last yr,not that that says much anyway.

sryanbruen

Billcarson wrote: »

Would lead to some great convection. Had some lovely big hail showers in a similar set up last yr,9/10c in the sunshine between the showers,down to around 4c in the showers. Temporary hail coverings .I love those sort of days this time of yr.

Thought the late april cold snap last yr was the most interesting weather we had last yr,not that that says much anyway.

The very warm days in September were what I found the most interesting part of 2016.

Elmer Blooker

snaps wrote: »

So after an extremely warm start to spring here in Southern Poland, we've hit the wall running! Had temperatures up to 27c 10 days ago and now the snow is back!

Currently -2c and snowing quite hard.

'The ground is too warm for snow to stick' myth exposed.
I never believed it anyway, if the air temperature is low enough snow will stick.
Meanwhile the endless gloom and drought continues.

JCX BXC

Elmer Blooker wrote: »

'The ground is too warm for snow to stick' myth exposed.
I never believed it anyway, if the air temperature is low enough snow will stick.
Meanwhile the endless gloom and drought continues.

It's been snowing in Munich past few days, quite heavy too and nothing has stuck. I'd imagine that's to do with ground temperatures.

Billcarson

sryanbruen wrote: »

The very warm days in September were what I found the most interesting part of 2016.

Sadly though that led to a most uninteresting winter. These days warm/very warm September's tend to be followed by winters with a lack of cold and snow. That was my fear last September and my fear came true

Btw I'm not saying a cool/cold sept leads to a cold winter ,no correlation there ,but a warm sept seems to have a correlation with a mild winter in more recent times ,eg off the top of my head 2006,2007,2011,2013 and of course 2016. Sorry for straying off topic.

Cloudio9

Newstalk are running with a story that Summer is coming for a few days and then talking about temps of 12-15 degrees. Surely that's average for mid-late April. Wtf are they on ?

http://www.newstalk.com/Summer-is-coming-for-the-next-few-days

who_ru

Cloudio9 wrote: »

Newstalk are running with a story that Summer is coming for a few days and then talking about temps of 12-15 degrees. Surely that's average for mid-late April. Wtf are they on ?

http://www.newstalk.com/Summer-is-coming-for-the-next-few-days

Was in Italy last 7 days, 20c to 23c every day. Already depressed being back here.

JCX BXC

Start of May should be nice looking at M.T's forecast.

Billcarson

Ukmo for next Tues,wind coming right down from the pole.

Gaoth Laidir

Elmer Blooker wrote: »

'The ground is too warm for snow to stick' myth exposed.
I never believed it anyway, if the air temperature is low enough snow will stick.
Meanwhile the endless gloom and drought continues.

It's not a myth. We've been through this all before so I won't explain it all again.

Explain this. How does snow melt on a warm windscreen as you're driving along in your nice warm car when it's Baltic outside? It melts because of transfer of heat to the snow. Of course if it's snowing heavy enough then eventually it cools down the glass faster than the warm air inside the car replenish the heat.

It's the same with ground. Initially snow will melt if the ground is above freezing. How could it not? Depending on the rate of snowfall the bulk of the snow builds up and removes surface heat from the ground and the air inside the snow also insulates the snow.

You think because it was warm in Poland recently then the ground is warm again? Not so. While it was snowing yesterday morning in Warsaw airport the grass minim temperature was reported as 0 °C with a 3-cm covering of wet snow. The morning before the grass minimum was -6 °C. Of course during yesterday the ground (and air) heated up and the snow melted.

JCX BXC

West Clare,

Temperature 10.4c
Wind dead calm
Humidity 99%
Clear skies

Shallow bit thickening fog.

Quite lovely to see, something a bit different to the dreary plain weather lately.

Elmer Blooker

Gaoth Laidir wrote: »

You think because it was warm in Poland recently then the ground is warm again?

What are you talking about? Did I say that?

Gaoth Laidir

Elmer Blooker wrote: »

What are you talking about? Did I say that?

You replied to snaps' post, which said:

So after an extremely warm start to spring here in Southern Poland, we've hit the wall running! Had temperatures up to 27c 10 days ago and now the snow is back!

Currently -2c and snowing quite hard.

You said that's the myth exposed. You brought up the ground temperature, no one else.

Elmer Blooker

Gaoth Laidir wrote: »

You replied to snaps' post, which said:


You said that's the myth exposed. You brought up the ground temperature, no one else.

if the air temperature is low enough snow will stick.

You didn't even bother to read the post you replied to, it wasn't that long!

MJohnston

Elmer Blooker wrote: »

You didn't even bother to read the post you replied to, it wasn't that long!

That's a bit disingenuous when the first line of your post was:

'The ground is too warm for snow to stick' myth exposed.

Elmer Blooker

MJohnston wrote: »

That's a bit disingenuous when the first line of your post was:

'The ground is too warm for snow to stick' myth exposed.

I thought it was quite obvious what I was trying to say - I said the theory that snow will not stick because the ground is too warm is a myth. I was basically saying its the air temperature thats important when it comes to lying snow or falling snow settling.
The middle of March 1999 saw the warmest St Patrick's Day on record followed by quite a heavy snowfall in April which stuck because it was COLD enough to stick. Feb 27th 2001 was a very wet day, as a low moved into the Irish Sea dragging down a cold northerly airflow temperatures plummeted and snow immediately began to stick not just on grass but even on concrete that was covered in surface water after a day of heavy rain.
I think I'll leave it at that.

Gaoth Laidir

Elmer Blooker wrote: »

I thought it was quite obvious what I was trying to say - I said the theory that snow will not stick because the ground is too warm is a myth. I was basically saying its the air temperature thats important when it comes to lying snow or falling snow settling.
The middle of March 1999 saw the warmest St Patrick's Day on record followed by quite a heavy snowfall in April which stuck because it was COLD enough to stick. Feb 27th 2001 was a very wet day, as a low moved into the Irish Sea dragging down a cold northerly airflow temperatures plummeted and snow immediately began to stick not just on grass but even on concrete that was covered in surface water after a day of heavy rain.
I think I'll leave it at that.

Your words in bold. And I'm saying it's not a myth. Of course the air temperature must be cold enough for snow to fall in the first place, but what happens to it after that depends on the ground temperature and rate of snowfall.

I'm not sure why you don't see the contradiction in your posts.

JCX BXC

Beautiful day here in West Clare, very sunny (and heat in the sun!), fog cleared about an hour ago leaving clear skies. Very light wind out averaging 3 knots and a cool temperature of 13.1c

sryanbruen

The anticyclonic gloom continues at Grange.

JCX BXC

17c being reported at Kerry airport since 2pm.

Lovely and quite warm here in West Clare, although if you're in the breeze it can feel cool.

Oneiric 3

Gaoth Laidir wrote: »

Your words in bold. And I'm saying it's not a myth. Of course the air temperature must be cold enough for snow to fall in the first place, but what happens to it after that depends on the ground temperature and rate of snowfall.

I'm not sure why you don't see the contradiction in your posts.

I thought air temps depended on the ground heating up in the sun? because the sun itself does not heat the air, but the ground (or any surface) which in turn heats the air above and around it.

I have noticed that even on very wet ground, that even wet snow falling from a heavy shower can begin to stick after a minute or two. This is probably due to, as you say, the snow flakes cooling down the ground rapidly as they make impact.

Gaoth Laidir

Oneiric 3 wrote: »

I thought air temps depended on the ground heating up in the sun? because the sun itself does not heat the air, but the ground (or any surface) which in turn heats the air above and around it.

I have noticed that even on very wet ground, that even wet snow falling from a heavy shower can begin to stick after a minute or two. This is probably due to, as you say, the snow flakes cooling down the ground rapidly as they make impact.

That happens during the day of course, and more so at this time of the year compared to January (solar irradiation today is more than double that at the end of December). However at night it's obviously not the case. The land in Spring still has cold down to its depth so whatever surface heating goes on during the day can be lost at night. So a cold airmass over cold land can allow snow to stick but the same airmass over warm (above zero) land (say on a sunny morning in April) and the snow will melt. As the day goes on the land warms the air and the snow turns more to rain.

Meteorite58

Stunning day here in Tralee. Got up to 16.9C and currently 14.8C under a near total blue sky.

River Feale very low in Listowel today.



Lucky to have had so much sun here looking at the rest of the country ( sat pic around mid day )



1036.2 hPa here dropping slowly from 1037.8 hPa

Harry Palmr

Is this the dullest persistent HP regime ever?

JCX BXC

Harry Palmr wrote: »

Is this the dullest persistent HP regime ever?

Not here

Think I got slightly burned today...

km79

Dull again but I don't care
Love this dry weather

snaps

This morning in Southern Poland. -5 and locally 20cm snow and above 1000m 60cm.

Cold night ahead tonight down to -10 and then hopefully warming up a bit!

snaps

Regarding some of the posts earlier about air and ground temperature.

My house is at 600m asl. Yes we had some extremely warm temperatures nearly 2 weeks ago but its been cooling down quite significantly since then with some severe air frosts at night due to the clear skies.

Here is a different situation to Ireland and falling snow.

1) We have no warm sea near us (Baltic sea is 700km away and Adriatic is about 800 km away)

2) Our ASL height is fairly high! ( So snow has less distance to travel through warm air before it hits the ground)

3) We can have snow with 0c 850hpa uppers quite easily.

4) Snow also can fall but not settle if air temp is as high as 6c (It quite often does), again this is down to the snow only falling a few hundred meters.

If you look at the snow depth around the car compared to the top of the car, that shows the example well. Where the sun had heated up the dark concrete around the car yesterday, the snow originally melted when it first started to fall, but on top of the cold metallic car it had settled.

sryanbruen

Harry Palmr wrote: »

Is this the dullest persistent HP regime ever?

NOT AT ALL..... look at December 1991 and come back to me.