Autumn

[summer blizzard]

The arrival of cold upper temperatures is as much a part of Autumn as leaves changing colour and falling off trees... IMO.

Anyway, -20C isotherm down to t27. All the rain and wind really makes it feel like Autumn has arrived, I for one will be glad to see the back of summer, don't enjoy the warmth much!

GFS12z has the -20C isotherm in just 15 hours. Bring on the -25C isotherm!

[MP-R]

Personally I'm hoping for a spell of weather like November 2009, perhaps not as long but with a raging Atlantic and rPm showers days a plenty.

[Gavin P]

Personally I'm hoping for a spell of weather like November 2009, perhaps not as long but with a raging Atlantic and rPm showers days a plenty.

They'll be plenty of time for that in January.

[Cymro]

Autumn is setting in good now, leaves beginning to clutter the sides of streets all be it only a few so far, leaves turning yellow on all oak and hazel now. Nights are drawing in and there is that notorious chill in the air .

[ZONE 51]

I read a post (model technical thread) that this auturmn could be the coldest since 93!

i can only think that a block to the rough atlantic is likely then?

resulting in a dry and cold oct/nov?

my thoughts in a previous post are based on only if the high dont block the atlantic.

If a strong or a cat5 hurricane formed then this would play with the model output.

I would not mind a cold sunny high, but i do like active atlantic systems.

Edited September 8, 2010 by nimbilus

[laserguy]

Autumn? Not half! Just returned from a trip down the fields with 12lbs of fat,juicy elderberries (the 'English grape') - enough to make 4 gallons of fabulous wine!

[BornFromTheVoid]

GFS12z has the -20C isotherm in just 15 hours. Bring on the -25C isotherm!

-20C isotherm confirmed!

Now to start the hunt for -25!

Have you any figures on when the earliest that's been seen last few years?

[summer blizzard]

-20C isotherm confirmed!

Now to start the hunt for -25!

Have you any figures on when the earliest that's been seen last few years?

Excelent, that is a full ten days earlier than 2005, our nearest rival for the -20C isotherm since at least 1997.

Our nearest rival for the -25C isotherm is again 2005, which had the -25C isotherm form on the 28th September and also 2007 which saw the -25C isotherm form on the 1st October.

Edited September 8, 2010 by summer blizzard

[summer blizzard]

Strengthening

2002

1993

1983

1978

Dec – 4.9C, 0.2C below average

Jan – 5.0C, 0.8C above average

Feb – 4.6C, 0.4C above average

Weakening

2007

2004

1998

1991

1974

1972

1970

1965

1960

1956

Dec – 5.0C, 0.1C below average

Jan – 5.1C, 0.9C above average

Feb – 3.6C, 0.6C below average

Mature

2009

2000

1995

1988

1986

1981

1979

1976

1967

1964

1962

1958

Dec – 4.3C, 0.8C below average

Jan – 2.8C, 1.4C below average

Feb – 2.7C, 1.5C below average

I have gone over the QBO data for +QBO winters since 1948 and compiled the average temperature of the winter months.

As you can see, +QBO winters typically have cool Decembers no matter what, however mature +QBO winters are statistically coolest, averaging well below average.

The good news is, of the three anologues which match the current QBO pattern best (1992, 1987 and 1982, so the winters of 1993, 1988 and 1983), one was a mature +QBO's, though the others were strengthening. This is great news for the winter and looking at that we can also deduce that 2008/2009 was so cold because of the mature +QBO conditions and there is a slightly better chance that we will see mature conditions because only 1987 saw a bigger rise between July and August, and that is the mature anologue, so at the very least, we are odds on to see mature conditions during Febuary.

For anybody wondering why this is in the Autumn thread its because the winter thread is closed and the QBO will have its first peak sometime during the Autumn. I will do the same for La Nina tonight if i can.

Edited September 8, 2010 by summer blizzard

[snowlover2009]

Strengthening

2002

1993

1983

1978

Dec – 4.9C, 0.2C below average

Jan – 5.0C, 0.8C above average

Feb – 4.6C, 0.4C above average

Weakening

2007

2004

1998

1991

1974

1972

1970

1965

1960

1956

Dec – 5.0C, 0.1C below average

Jan – 5.1C, 0.9C above average

Feb – 3.6C, 0.6C below average

Mature

2009

2000

1995

1988

1986

1981

1979

1976

1967

1964

1962

1958

Dec – 4.3C, 0.8C below average

Jan – 2.8C, 1.4C below average

Feb – 2.7C, 1.5C below average

I have gone over the QBO data for +QBO winters since 1948 and compiled the average temperature of the winter months.

As you can see, +QBO winters typically have cool Decembers no matter what, however mature +QBO winters are statistically coolest, averaging well below average.

The good news is, of the three anologues which match the current QBO pattern best (1992, 1987 and 1982, so the winters of 1993, 1988 and 1983), one was a mature +QBO's, though the others were strengthening. This is great news for the winter and looking at that we can also deduce that 2008/2009 was so cold because of the mature +QBO conditions and there is a slightly better chance that we will see mature conditions because only 1987 saw a bigger rise between July and August, and that is the mature anologue, so at the very least, we are odds on to see mature conditions during Febuary.

For anybody wondering why this is in the Autumn thread its because the winter thread is closed and the QBO will have its first peak sometime during the Autumn. I will do the same for La Nina tonight if i can.

i dont really, follow? does that mean there is a good chance of another very cold winter. looking at the mature list, it seems you have listed all of the past cold winter.

[summer blizzard]

i dont really, follow? does that mean there is a good chance of another very cold winter. looking at the mature list, it seems you have listed all of the past cold winter.

Sorry, i did not really explain. Basically, the QBO has 5 phases to it over the course of its positive and negative occilation. The negative phase is a simple strengthen and weaken, with the average peak at around -25, or a standard deviation of -2. The positive phase is more complicated, because it strengthens, weakens and then has a secondary higher peak before weakening, i call the phase between the first and second peak the mature phase and it is this phase that is statistically correlated to a cold winter.

This winter will feature either a strengthening or mature positive QBO, therefore it is reasonable to assume that we would see a cool December based on the QBO alone, however January and Febuary are on a knife edge.

[Weather-history]

Chat Moss: More and more notable the dying back of wild vegetation, leaves changing colours and rate of leaf fall increasing now.

Wild blackberries ripened and edible, apples ripened. Horse chestnuts are becoming larger and close to ripening.

Edited September 25, 2010 by Mr_Data

[Tom D]

Yesterday was the first day it actually started feeling like Autumn here; some trees are going yellow, the wind was gusty and it was dull and drizzly most of the day. Today is beautiful, clear skies and a cool breeze.

I believe we can tell a lot about the coming winter from what Autumn is like. If it's early, it bodes well for a cold winter like last year.

Edited September 25, 2010 by Tom D

[Cymro]

Well the trees have been turning here for a while but last weekend I ventured to blackpool and you could tell the further north I was travelling the earlier Autumn had taken it's holed. Even from where I live in the mountains when you go down to Swansea its still fairly green in comparison. Autumn is well underway now methinks.

[summer blizzard]

Excelent, that is a full ten days earlier than 2005, our nearest rival for the -20C isotherm since at least 1997.

Our nearest rival for the -25C isotherm is again 2005, which had the -25C isotherm form on the 28th September and also 2007 which saw the -25C isotherm form on the 1st October.

-25C isotherm is forecasted to form in 30 hours, this would be the 4th October, so we have lost 16 days on 2005, most likely due to recurring hurricanes pumping warm air into the Arctic.

[summer blizzard]

We have indeed achieved the -25C isotherm, six days later than 2005. I will look for data regarding the appearence of -30C tommorow.

[BornFromTheVoid]

We have indeed achieved the -25C isotherm, six days later than 2005. I will look for data regarding the appearence of -30C tommorow.

Good stuff. How did we do compared to the other years?

[fear sneachta]

Autumn? Not half! Just returned from a trip down the fields with 12lbs of fat,juicy elderberries (the 'English grape') - enough to make 4 gallons of fabulous wine!

Ah cool! I've never tasted Elderberries. Are they definitely safe to consume? I heard they were mildly toxic with cyanide?

I love all the mushrooms and berries of autumn. Blackberries are my favourite.

[Weather-history]

Chat Moss: More and more notable the dying back of wild vegetation, leaves changing colours and rate of leaf fall increasing now.

Wild blackberries ripened and edible, apples ripened. Horse chestnuts are becoming larger and close to ripening.

Horse chestnuts have split open now. Plenty of blackberries.

[laserguy]

Ah cool! I've never tasted Elderberries. Are they definitely safe to consume? I heard they were mildly toxic with cyanide?

I've never tasted raw elderberries for that very reason,though I'm not sure about the cyanide bit. Making wine involves simmering them for a while and like kidney beans,the litte poisonous/irritant constituent is destroyed. Trust me - elderberries make the finest red wine imaginable!

[noggin]

Trust me - elderberries make the finest red wine imaginable!

When my better/worse half and I got married, we had a d-i-y reception and had home-made elderberry wine and elderflower wine. I can honestly say that they were the most delicious wines I have ever had the good fortune to drink.

Hard to describe really, but the elderflower wine was the equivalent in taste to the visual beauty and fragrance of the most exquisite flowers.

I'll shut up now.

[Northernlights]

Most amazing amount of berries on the holly this year making the bushes almost totally red and dwarfing the green leaves.

[laserguy]

Most amazing amount of berries on the holly this year making the bushes almost totally red and dwarfing the green leaves.

I'll take your word for that as I'm red-green colour blind! Noggin,elderberry wine is dead easy to make and is quite tolerant of inexact quantities used,but whilst elderflower is truly sublime if done correctly it can smell (and presumably taste!) exactly like stale cat-pee if you go just a little OTT with the flowers!

[Isolated Frost]

Extremely autumnal here now, not passed 20C for around 50 days, and had our first air frost yesterday morning here in Durham.

Most trees are Red, or yellowy-orange, and even the ones that don't turn till' December, have done so already. Must say, this Autumn has been more marked then others...

[Winter Warmer]

just been out with the dogs and its warm and breezy