-
Posts
18,981 -
Joined
-
Last visited
-
Days Won
10
Content Type
Forums
Blogs
Gallery
Events
Learn About Weather and Meteorology
Community guides
Posts posted by Bristawl Si
-
-
- Popular Post
- Popular Post
21 minutes ago, Flub136 said:Sorry if this is in the wrong domain but please could someone direct me to a good explanation of “dam” and “dam thickness” and its relation to snow production. Thanks in advance.
From UK MetOffice website:
Thickness lines
Pressure decreases with altitude, and thickness measures the difference in height between two standard pressure levels in the atmosphere. It is proportional to the mean temperature of this layer of air, so is a useful way of describing the temperature of an airmass.
Weather charts commonly show contour lines of 1,000-500 hPa thickness, which represent the depth (in decametres, where 1 dam = 10 m) of the layer between the 1,000 hPa and 500 hPa pressure levels. Cold, polar air has low thickness, and values of 528 dam or less frequently bring snow to the UK. Conversely, warm, tropical air has high thickness, and values in excess of 564 dam across the UK often indicate a heatwave.
Hope this helps your understanding.
- 3
- 3
- 4
-
Glorious Winter morning, sunny, 4c.
-
19 minutes ago, Mapantz said:
5.6 hours of sunshine today. That is the most hours since November 25th.
I power washed all of my paths/patios today. They got very slippery with algae and slimy shizz growing.
A satisfying 4 hours!
Hmm...need to do ours over next couple of days. Normally, do them once/year around mid-March/early April ready for Spring and Summer, but the wet few months since end Summer means they're bad and v slippy right now.
- 1
-
Classic use of the English language
"....as they butt up...."
- 1
-
-
Lack of instability on the charts, to our south and east, seems to be the key (snow making) ingredient that is missing.
UK High with dry, cold, sometimes sunny days and frosts at night, seems to be the weather for next 10 days or so. Imby - colder than average but not overly cold - well that's what i'm seeing fwiw.
- 2
-
-
Another fail from Meto for this afters/eve.
Charlie boy on local news yday eve, showed rain affecting area south and east of Bristol. It's been chucking it down last 3 hours.
-
Bone dry for the next week; i'll take that
- 6
-
- Popular Post
- Popular Post
According to "Severe Weather Europe", earlier today:
A Stratospheric Warming event has now begun, and is expected to play its role in the large-scale weather pattern change in the first half of January. With snow events over the United States and cold air periods over Europe, the second winter month finally delivers proper weather.
- 11
-
An absolute deluge all morning, but now we have blue skies.
-
5 minutes ago, Bald Eagle said:
Just dipped in for my weekly giggle at the mad thread. The word ' potential' is being used alot by those picking one computerised prediction from hundreds. Very amusing. Anyone see the darts last night?
Yep. The final 8.15 this eve. One of my mates has Luke The Nuke at 80/1, pre-tournament.
-
-
Heavy rain all morning but it cleared in last hour or so. There was hardly any wind this morning but in last 20 mins it's turned extremely windy.
- 1
-
8 minutes ago, SunnyG said:
I have never understood this. When I lived in Rome (way more dry than UK can ever get) we never had hose pipe bans or other water restrictions. Never heard of it over there...
Depends where you live re water shortages. If you're in an area near to a constant water source, like here, there's never issues re long dry periods. Our area gets its water from a decent reservoir infrastructure, but more importantly from sources in the Welsh moutains, hills and the source of the Severn.
Stating the bleedin' obvious, as well, is the population density issue, which London and the SE have to deal with.
-
12 minutes ago, Anti-Mild said:
I've not posted for a good while in the forum - more of a lurker But i've been a member for getting on 2 decades, and some things never change.
Why, when looking at the model outputs, are people still comparing the run with the previous run, rather than with the same run 24 hours ago?
The Model Discussion thread is an absolute playground farce at times! "Disastrous run", "no it's not, it's epic", "oooh that's the chance of cold gone", "woooah, snowmageddon incoming".
Maybe I'm grouchy because I've had to work, but it's tiresome.
Been thinking much the same, lately. Big John Holmes has always said, for years, that peeps should only compare like-for-like e.g. 06z run with 06z run 24 hours earlier, NOT 06z v 12z from same day.
Still, after the dullfest and rainfest of last couple of months looks like we're in for a quiet period, with perhaps some sun, albeit colder, from this weekend for a week or so.
A welcome respite from the doom, gloom and incessant wet stuff.
-
Looking at Sean's tabs no surprise, for here. It's been dull, dreary most days.
Although, the Meto's station at Almondsbury is 'just up the road' from me, it shows 5 hours more sun than the 'Bristol' one. If the Bristol station is the guy's in Horfield i doubt there's a 5 hour difference, in reality.
-
It's been a conveyor belt of really heavy downpours here, all day today.
Oh, for a dry week or two.
Edit: and now, at 15.30 it has gone so dark, it's like night time
-
Heavy squall just hitting us, here. Monsoon-like rain, fierce winds.
- 1
-
13 minutes ago, SilverWolf said:
Anti climax here! A bit windy and some moderate rain… now raining lightly. Was looking forward to a proper squall! Oh well.
Yeah. Much the same here, in the end.
- 1
- 1
-
Blowing a hoolie here, now. Squall line approaching, i think, looking at latest radar.
-
3 minutes ago, LetItSnow! said:
The cold, wet June but markedly better July and August can't be too dissimilar to that of summer 1991.
"Better July"?! Really?!
June turned out pretty good here, bar the 1st week. July was damned awful.
- 1
-
8c, lashing it down....again. Dark and dreary.
OFAH on Gold to lighten the mood.
- 2
-
Met Office and BBC Weekly/Monthly Outlooks
in Spring Weather Discussion
Posted
Upgrade Meto. Downgrade Meteogroup (BBC).
There's only one way to find out....