Current state of La Nina

[Snowyowl9]

What do the experts think will happen during spring with this current La nina is it similar to 2000 of course it`s not going to be exactly like it by quite a way in terms of dates just a previous year to go by though of what could happen.

This time 8 years ago nothing but a mild day.

http://www.wetterzentrale.de/archive/2000/...00120000223.png

The only wintry day during the rest of Feb here was this which gave hail,sleet and snow showers with temps around 1c above in the daytime with it close to 0c at night.

http://www.wetterzentrale.de/archive/2000/...00220000228.png

It wasn`t until March 4th when the next air frost came from a brief N-ly must of been snow showers in the north,nothing here.

http://www.wetterzentrale.de/archive/2000/...00120000304.png

http://www.wetterzentrale.de/archive/2000/...00220000304.png

Then it was mild/very mild until the end of March with no more frost until the 26th ground frost,then a change of pattern with a high building just to the north giving a colder NE-ly with a few odd snow showers just a sprinkling with 3 air frosts down to -4c.

http://www.wetterzentrale.de/archive/2000/...00220000328.png

http://www.wetterzentrale.de/archive/2000/...00120000329.png

As April came as a complete shock at the time with not seeing any forecasts aswell that was our winter for snowfall similar like last february was it gave us 9 inches in all with early blizzards and alot of the roads(lanes) were blocked also brought a tree down with even severe gales

Had more snow on the 11/12th which gave a slight covering also with just a few snow drifts remaing by April 18th.

[NL]

Mr Maunder has touched on it, solar cycle 24 should have started 14 months ago but it still hasn't.

BFTP

It actually did start around 4th Jan,

but for the last 18 days there has been

no sunspot activity observered.

[The PIT]

It actually did start around 4th Jan,

but for the last 18 days there has been

no sunspot activity observered.

Perhaps it hasn't wasn't. Wasn't there another sunspot two years ago that singled the start of cycle 24??? Or was that it the wrong place?

[NL]

To be honest i dont know what really signifies the

beginning ...how many sunspots does there have to be

to start a cycle.. perhaps the sun hasnt been studied

early enough to prove this 11 year cycle is regular..??

Something for me to read up on i guess.

[BARRY]

but wasn't that sunspot unusually, in that the magnetic polarity was reversed

Edited February 23, 2008 by BARRY

[wysiwyg]

http://sidc.oma.be/news/101/welcome.html

The appearance of one sunspot isolated in time, even if it has the correct magnetic configuration, can be a false start if this sunspot is not followed by a sequence of sunspots with the correct magnetic configuration. But both the December and January event give a good indication that solar cycle 24 is about to arrive in its full glory.

I read somewhere that it is not actually possible to say that the new cycle has started until well into the cycle (i.e. retrospectively)

[kold weather]

As interesitng as this talk of solar cycles is it is takin this thread off topic, you can always discss this in the science forum:

http://www.netweather.tv/forum/index.php?showforum=21

As for La Nina, still looks we are going to se this la nina get into the top 3 strongst since 1950 at least for the month of Feb though for the winter as a whole it'll probably end up borderline mod/strong.

The future is going to be interesting, with a la nina peaking so late it dos at least heighten the chancee of a multi-year la nina event, just going to have to see what occurs in the next few months and how much it decays.

[Mr Maunder]

It actually did start around 4th Jan,

but for the last 18 days there has been

no sunspot activity observered.

To try and clear things up here!

There has, to date, been one small sunspot that meets the characteristics of a Cycle 24 spot in that it has appeared in a high latitude and has the expected polarity. So, you are right that we have had a Cycle 24 sunspot. But that does not means that Cycle 23 has ended!

There are a number of definitions as to when an existing cycle is condidered to have ended and the next cycle started. It is all quite complex but, as a layman, the best rule of thumb guide I can find is when the "smoothed sunspot number" for the new cycle exceeds the "smoothed sunspot number" for the previous cycle. The Smoothing takes place over a running 12 months. (However the actual official cycle start date will be decided by the worthy "academics" who decide these things!)

So, as we have 12 months worth of Cycle 23 sunspots already in the bag, so to speak, quite a few Cycle 24 suspots are going to have to appear before Cycle 24 can become the ascendant cycle. So unless Cycle 24 really gets going (and we still only have one spot!) then it may be another 6 to 9 months or even a year before Cycle 24 will "officially" begin.

Will 24 be a strong or weak cycle? Opinion seems to be moving towards a weaker cycle due to the length of Cycle 23 (often a precursor to a weak cycle) and the fact the Cycle 24 has not yet kickstarted. A weak cycle could mean an ascendancy of La Nina over El Nino - with temperature implications.

However, as ever, only time will tell.

Hope this helps.

MM

Edited February 23, 2008 by Mr Maunder

[J10]

At this stage what are the early indications of the state of La Nina into next winter,

and why exactly does a strong La Nina mean a mild winter, but a weaker mean increased chance of a colder one.

[Devon-Nelly]

I can see La Nina sticking around until well into next year, weaking off in the summer slightly, but becoming stronger again during next winter though i dont think it'll get as strong as it is now.

What is a Multi La Nina event? and how does it effect weather pattens?

[summer blizzard]

At this stage what are the early indications of the state of La Nina into next winter,

and why exactly does a strong La Nina mean a mild winter, but a weaker mean increased chance of a colder one.

I can't answer that, though model guidens suggests neutral mostly (useless at this range anyway...), however i have been looking at the duo-monthly anologues (for december and January - within 0.3 either side standar deviation), and those anologues seem to indicate a weak La Nina spring and summer (MEI index only).

[kold weather]

Then again I'm not sure you can use the MEI as much nowdays, I've just been reading a discussion on easternuswx which is saying that there has been a large dsconnect betweetn the MEI and the actual strength of the la nina, I far perfer just to ue the raw as surface anomalies as a gauge.

As fr strong La Nina, I can't say I really know why they nearly always lead to mild winters but the fact that every winter since 1950 including this one tat has been a strong la nina have had a +ve NAO probably sugests the jet stream positioning has a large role to play.

[Lettucing Gutted]

As fr strong La Nina, I can't say I really know why they nearly always lead to mild winters but the fact that every winter since 1950 including this one tat has been a strong la nina have had a +ve NAO probably suggests the jet stream positioning has a large role to play.

I think strong La Ninas cause the jetstream to go north because La Ninas causes strong upper level warming other the mid latitudes which is caused by adiabatic warming from upper level ridges which are in turn induced by the cooling in the equatorial Northeast and Southeast Pacific Ocean.

[summer blizzard]

Then again I'm not sure you can use the MEI as much nowdays, I've just been reading a discussion on easternuswx which is saying that there has been a large dsconnect betweetn the MEI and the actual strength of the la nina, I far perfer just to ue the raw as surface anomalies as a gauge.

As fr strong La Nina, I can't say I really know why they nearly always lead to mild winters but the fact that every winter since 1950 including this one tat has been a strong la nina have had a +ve NAO probably sugests the jet stream positioning has a large role to play.

Yes, the problem with the MEI index is that it uses six different factors to determine the ENSO state, while in theory this could be a better measure of the ENSO, in reality there are several potential flaws, for instance, despite La Nina being strong in regards to sea surface temperature anomolies, if we see tropical convection occuring (not a La Nina charecotoristic), then this may explain a weaker value despite an actual strong La Nina, so in this regard, it is more of a measure of how the ENSO state is interacting with the atmosphere.