Autumn 2011

[cooling climate]

Well I for one sure hope we get a better winter than last year.

By that I am obviously only talking about January and February.

Apart from the first few days of January and a couple at the end

plus the last day of February the 850 -5 isotherm was no where

to be seen over the majority of england and wales apart from a

brief flirtation with kent around the 20-22nd of the month.

The general public that I have come into contact with also agreed

that from the turn of the new year onwards there was no winter

unless you count a little sleet on the 7th of January.

I would however stick my neck out even this early in the autumn

to say that so long as we do not see the sun ramp up for a prolonged

period of time then a big winter ( severe perhaps) could very well be

on the cards with a very negative NAO and AO towards end of November

through December,January and even well into February.

[Summer Sun]

Not sure if this has been posted or not,

Although we expect stormy and wet weather for the British Isles during September, we anticipate that the general weather pattern will settle down dramatically during the latter part of the season with high pressure dominating from late September onward. Early signs from the global forecasting system (GFS) indicate that sunny but cool conditions will begin to set in by mid-September, with the jet stream slipping southward blocking the passage of Atlantic storm systems. From the mid-autumn period onward Weather Logistics UK predicts that hurricanes, and the remnants they leave as extra-tropical storms, will dissipate over the USA as they begin to track further southward.

That would be about right with the CFS charts going for a rather dry and cool October and November, i wounder if the sunshine amounts get more prolonged if this does indeed happen.

http://www.weatherlo...rdpress/?p=1289

[Frodo]

Hi all..newbie here. I was wondering if someone could answer me a question? I have been following your threads on winter 2010-11 and your thoughts on this autumn 2011. It seems that people have different ideas of when one season ends and another starts and I wondered why you don't take the Equinoxes and Solstices as the markers for your seasons? This is a genuine question from a novice..

[sebastiaan1973]

Some nice reading. http://www.americanwx.com/bb/index.php/topic/25574-possible-snow-gradient-explanation/

[BLAST FROM THE PAST]

Some nice reading. http://www.americanw...nt-explanation/

Its an interesting read.

BFTP

[Weather-history]

That would be about right with the CFS charts going for a rather dry and cool October and November, i wounder if the sunshine amounts get more prolonged if this does indeed happen.

I think you are hanging onto the CFS charts far too tightly. IMO, they are next to worhtless, The latest ones have changed again.

[knightrider]

After the last couple of years I'm expecting a relatively mild autumn and winter in comparison with alot of rain and some strong winds aswell at times!

[Aaron]

I just hope, for the love of god, we can get an above average month for rainfall. PLEASE!

[ZONE 51]

http://weatherfaqs.org.uk/node/189 - all learners wanting to know what the charts mean this link is very good, simply explained and well set out.

[ZONE 51]

seeing more winter topics fire up im actually thinking where near end of season!! i do like the topics of course as i am a winter fan! but anyone got ideas for autumn topics then there very welcome. mind you i had started natures signs of winter and that was swiftly shut!

-

Edited September 16, 2011 by ElectricSnowStorm

[russ49]

not sure where to put this so mods please move this in the wrong thread

i have just been seeing on the various weather reports on the internet that the la nino is getting a lot stronger and i know it has a cooling effect in the pacific the question i have is what will the possible effect be to us if any this winter

Edited September 16, 2011 by russ49

[sebastiaan1973]

Yesterday at http://www.rtl.nl/xl/#/u/6e154d3a-6ed7-49f5-8906-4346f9b7c32f/ (a Dutch television show, sorry no English subtitles) it was reported that Meteo Consult expects a cold winter in the Netherlands. Due to a negative NAO. They get their information of World Climate Service.

[Slowpoke]

That all time October Max temp record is going this week!

[damianslaw]

The current weather reminds me of conditions I experienced in New Zealand south Island in late March 2006 (there early autumn). Blazing blue skies and sunshine with temps comfortably in the low-mid 20's and brilliant red and golden orange leaves on the trees. It also reminds a little of conditions last October in the south rockies of Canada - not quite as warm, but definately a similiar 'continental' feel with very dry air and the splendid colours of autumn.

I'm hopeful of a much better autumn display than I was three or four weeks back when I was fearing early autumn storms would strip the trees earlier than normal. I think the current sunshine and heat will do wonders, the leaves will store so much more sugar and be forced to turn into much deeper colour. Looking forward to some wonderful scenes in the weeks to come, last week of october/first week of november is the best time of year for autumn colours I always say.

[stewfox]

I wonder why so many didnt vote for 28c plus this autumn, then realised this was a thread started in May !

[ITSY]

A quick look at the 12Z provides a very interesting development in my opinion. The highs get going to our northwest at the (obviously unreliable) end of the run - making it, now snow kinda cold, but relatively cold average winter maxima with sub zero nights by day. It does show a possibility different to what we've seen in the last week or so. If, and its obviously an open ended hyperthetical IF, those kind of conditions to set in play then the idea of James Madden's snow in October might not seem that absurd.

[ZONE 51]

When we head through into October the chances of it being cold increase, this is of course because this month can be cold-as simple as that, so my point is here is that as we have unusual heat now this makes for a harder shock when normal cold comes, we could be in frost now, so a sudden change of weather conditions is more likely, meaning we are not meant to be in a heatwave, when this pattern changes then a snap back to normal temperatures is going to be harsh, this weather is amazing but its not breaking us in to the cold slowly, a sudden shockwave of temperature change is on its way!

Edited October 1, 2011 by ElectricSnowStorm

[ITSY]

The current outlook for the next couple of weeks - if taken as an indication for winter, which it may of course NOT be - suggests that the heights will come from Scandi as oppossed to Greenland. Scandi vs. Greenland = what's better?

[Isolated Frost]

The current outlook for the next couple of weeks - if taken as an indication for winter, which it may of course NOT be - suggests that the heights will come from Scandi as oppossed to Greenland. Scandi vs. Greenland = what's better?

Scandi highs - depending on the position of them. If they are too far south or have a north-south positioning, then we will get milder se/s'lies. if it's west-east position and more in Northern Norway/Lappland, then we get cooler easterlies which if you live in Eastern England or possibly the East of Scotland can give very potent snow showers across the N Sea (probably better for Cambridgeshire for you), but if the air is not cold enough, we get low, grey cloud with some sleet/wintriness on the coast.

Greenie highs, usually give us N/NW'lies but if we have a lp system in the N Sea we can get cold easterly/north-easterly winds bringing dramatic snows, but usually give cool, wet weather from the north if we do get affected by them - it depends on how high the jet is.

Personally, as an east coaster, I'd like Scandi highs giving very cold uppers and moisture with potent showers over here, but then again last winter we had greenie hp dominate and due to heights in svalbard/arctic and low pressure in biscay/s england, we got cold easterlies with plentiful snow in ne england.

All in all - Scandi's probably better for you when they work - greenie's more reliable for cold - scandi's can give monster cold or some averageness.

And also, 2-1

[Aaron]

February 1991 is a good example of a Scandi High that delivered snow and cold temperatures for all.

[Isolated Frost]

February 1991 is a good example of a Scandi High that delivered snow and cold temperatures for all.

Yes, cold so extensive and potent it's amazing! I'd only dream of uppers like that this year, or any other one infact - i'm happy with my marginal sleety incursions for now!

[A Winter's Tale]

I've got questions regarding Scandi and Greenie Highs:

1) Which one is Colder (I suspect Scandi)

2) Which one is Snowier (Scandi?)

3) Which one is more widespread (Greenie?)

4) Which one lasts the longest (Greenie?)

[Isolated Frost]

I've got questions regarding Scandi and Greenie Highs:

1) Which one is Colder (I suspect Scandi) Scandi's can provide much colder air to Britain, but usually don't apart from in some rare cases (Jan 87' Feb 91')

2) Which one is Snowier (Scandi?) West/North probably Greenie - East/South usually Scandi, although east coast can do well from Northerlies

3) Which one is more widespread (Greenie?) Usually Greenie yes, but Scandi's also have the power to do so

4) Which one lasts the longest (Greenie?) Scandi's I'd imagine - Greenie's can do very well and last a while if they reach here in the first place, or we have a very Nly or Sly tracking jet.

[Thundery wintry showers]

I think of the Greenland High as being the snowier of the two for most parts of the UK (except perhaps the southeast).  After all, you can get a very potent easterly blast when a Greenland High ridges over to Scandinavia (as happened in late November/early December 2010) just as you can when a Scandinavian High ridges over towards Greenland.   In addition, the other setups featuring a Greenland High, typically characterised by winds from the NW/N/NE, tend to feature troughs moving southwards in the northerly flow and bringing more organised/widespread snowfalls, as we saw repeatedly in the previous two winters.

I think the Scandinavian High is generally the colder of the two across southern and central England because it tends to bring a lot of continental air our way, and in addition to the January 1987/February 1991 type snowy easterly scenario, it can give rise to big "battleground" snowfalls when Atlantic fronts push against continental air.  However, I associate it primarily with cold dry cloudy weather, as quite often the coldest air remains locked out to the north-east and we get a lot of "inversion cold" continental airmasses from the SE, with insufficient cold at upper levels to trigger many snow showers over the North Sea.

We also have the February 1947 setup when we get both- essentially a large anticyclone sat to the north of the British Isles with centres over Greenland and Scandinavia- but this is pretty rare.

[Gavin P]

At times February 1947 actually had high pressure stretching fron Russia to Greenland to Canada.