beng

ftp://ftp.cpc.ncep.noaa.gov/wd52dg/snow/snw_cvr_area/EU_AREA That's got the snow cover area by month since 1973 - but I don't see any obvious pattern. Maybe the model details relate to specific areas in Siberia and snow depth rather than area? - not sure where we can see that level of data though.

http://www.nsf.gov/news/news_images.jsp?cn...820&org=NSF Anyone want to comment on the veracity of the above model. Basically when Autumn snowfall is above average in Siberia, this tends to create a more intense Siberian High pressure cell - which in turn leads to stratospheric warming at the start of January, sending the AO negative and leading to colder N American and European winters. It may well be put to the test this year, since the very low levels of Sea Ice should make more moisture available for snowfall (Sept-Nov) across Siberian and Northern Canada.

Hi GP - presumably the AO this winter might be influenced a great deal by the state of the QBO? In which case we need to hope the Easterly QBO maintains a decent strength until well into Feb - any idea on the likelihood of that? Another factor might be the state of the Arctic Sea Ice (or lack of it) - this may deliver large (relative to normal) snowfalls to Siberia and Canada before it completely freezes over - which may have some impact on winter synoptics (I suspect that's where chaos plays a big part). Ben

I'm not sure we should conclude that we can't have a winter colder than 95/96 - even in the Medieval Warm Period there were still severe winters, but they were much less common than say during the little ice age. I think it's still quite possible, just less likely. The Hale cycle is very interesting and it does seem to coincide with extreme weather in W Europe - whether this has an impact and leads to a very cold winter - or a winter extreme in another way, we'll see very shortly. It's also worth noting that the current solar cycle is longer than we've seen recently - indeed we may not reach the minimum until into next year. The hale effect, if it exists, could be more prolonged than say the 80s due to the extended minimum. One other thing - I noticed on Eastern US someone mentioning that the GLAAM or globally averaged atmospheric angular momentum is very low at the moment and traditionally this leads to extreme blocking patterns in winter months (I won't mention the year they quoted as it would sound like a ramp) - I'll be honest I've never heard of this before - would anyone like to comment as to what this is all about? http://www.easternuswx.com/bb/index.php?showtopic=139640

16.2c with rainfall around 130% of average. Basically while the jet has surged South through us during July, if my thinking is correct, it should be a much flatter pattern through Aug. This is based on the fact that we've seen a warming of SSTs to our direct North, which should allow the jet to move more to the NE across the UK (rather than digging SE). This promises some drier weather at times in the South with a few bands of mainly light rain. Further north, it should be less settled with the rain here falling heavier in nature. I should add that I don't see a real heatwave developing (ie temps 30+).

This is true, although one of those named storms I believe was quite controversial - the other thing is this year was predicted to be quite a bit above average (although obviously there's plenty of time for that to still happen).

I'm sure it's a factor - Accuweather also talk of our old favourite the Saharan dust playing a role too. That said I think we'd have expected a few more storms (tropical storms/depressions) to have formed further West in the early stages of the season - which hasn't happened either.

LOL - not sure what you mean :lol:

Erm did anyone say that? Answer No. All it means is that the likelihood of the coming winter having a significantly negative NAO looks decent. The NAO forecast is one of the main predictive tools the MO use when producing their winter forecasts. We should also note that the MO NAO forecast may not be the same as this gentleman on Eastern US - although his NAO forecasts appear to have a good track record. I'm not sure anyone in this thread has said we're going to have a cold winter? The thread is about what the MO NAO forecast is likely to be. When/if several of us issue severe January CET forecasts at the end of Dec this year (based on stratospheric warming, AO signals, seaweed and Mystic Meg) then please do advise caution :lol:

http://weather.unisys.com/surface/sst_anom.html Just to illustrate how poor June has been (although not technically cold in the CET zone) - have a look at the North Sea Temp anomalies now - the huge warmth has gone - indeed there's even signs of a negative anomaly developing off eastern Scotland - this must increase the chance that the CET value for July could be around average (or even below) if synoptics allow (something that I don't think was really possible in June due to that N Sea warmth and the predominance of Easterly winds).

http://www.easternuswx.com/bb/index.php?sh...40&start=40 An update from our Eastern US friends - over there our guru believes his NAO predictive method may now forecast winter 07/08 in the top 3 negative NAO winters. Currently the top 3 he lists are: 1. 63-64 -1.38 2. 62-63 -1.21 3. 76-77 -0.99 07/08 stands at -0.95 (based on the May/April figures) however during June his index is down at -1.532 - so an average of the 3 months would come in around -1.14 which would put 07/08 between 62/63 and 76/77 in respect of his NAO forecast scale. They also talk about La Nina - the general consensus being that it won't have much affect on the Atlantic NAO signal provided it gets no stronger than weak moderate.

Thought I'd bring this back as the negative NAO signal is strengthening. http://weather.unisys.com/surface/sst_anom.html http://www.emc.ncep.noaa.gov/research/cmb/...es/wkanomv2.png We have a very good tripole signal now - the N Sea positive anomaly (although still very high) has already moderated somewhat - and should continue to do so through July (this should allow CET values to trend closer to normal through the remainder of the summer IMO). As Gavin has stated - with sustained cold conditions these sea temps can change rapidly - although they will produce a warming effect (relative to the synoptics) whilst they remain so positive.

Yes a wet ground will lead to lower maximums since for the water to evaporate, it must take energy from the atmosphere. If heat is sustained for long enough though, the ground would dry and this could allow very high maximums into Aug if synoptic conditions allow (not that I see a particularly dry spell during this coming July).

http://www.bom.gov.au/climate/enso/ Fresh update today from Australia seems pretty bullish about la nina developing.

Thanks SF.

I think the local warm sea surface temperatures (particularly over the N Sea where the wind has frequently been coming from) are holding temperatures up at nighttime (and boosting them relative to the long term average during the day). Anyway it's my assertion that the current relative 'warmth' on the CET scale is more a legacy effect of the previous very warm 12 months - than the current synoptic pattern. 15 years ago I suspect we might have been looking at a below average CET at this point in the month based on the patterns we've seen. If we record similar synoptics on and off for the next 6 months (big if) - then we should start to see CET months returning to more average values (or below) as we lose the local positive sea surface temperature anomalies. For the moment though, it's going to be very tough to get a cool CET month this summer with those anomalies (that doesn't imply that it will be a great summer though). Also worth noting that CET doesn't tell the whole story (someone correct me if I'm wrong on this) since it's the halfway point between the max and min temperature for a day - rather than a mean average temperature for the 24 hour period.

Very good point GP about the AO it's worth noting that AGW theory predicts that the stratosphere should cool as more heat is trapped in the troposphere which doesn't bode well for negative NAO winters in the future (assuming that the theory holds true). The Arctic Sea ice situation may also have some impact too. At least this winter we shouldn't have an El Nino and Westerly QBO though. Fingers crossed for a fairly neutral enso this winter:) I'll hope for something a bit better than 05/06 - it wasn't that negative really and overall the Atlantic looks a bit cooler this year and the Pacific has a better signal too. http://www.metoffice.gov.uk/research/seaso.../nao/index.html

http://www.easternuswx.com/bb/index.php?showtopic=135457 Kold posted the above link on Two - hope he doesn't mind me linking to it here too. I think it gives a decent explanation of how the SSTs in May can impact on the NAO the following Winter. Most people on here will be pleased to note that the methodology described indicates (at this stage) a fairly potent negative NAO signal for the coming winter.

Thanks Stargazer, I might just have been lucky with that forecast though I'll see if my June one comes close (also for very wet with a of CET 15. :unsure: and if that one comes (which in a way i hope it doesn't) then I reckon I'll have done pretty well.

Great effort GP - as others have said you must have put a lot of time into this forecast. ECM is now showing hints in its extended run of high pressure settling to the West of the UK during June - so your June suggestion of a high to our west is looking very possible.

Down to 12c today based on Philip Eden's figures. http://www.climate-uk.com/

2003 - http://www.osdpd.noaa.gov/PSB/EPS/SST/data...t.5.19.2003.gif To me it looks like we're quite a bit cooler than 2003 across the Atlantic. http://www.osdpd.noaa.gov/PSB/EPS/SST/data...t.5.22.2004.gif 2004 - perhaps similar over the whole north Atlantic with the positioning of various anomalies differing. N Pacific is colder this year. Here's the may monthly mean for 1995 - there are indeed some big similarities! http://www.osdpd.noaa.gov/PSB/EPS/SST/data....95.anomaly.gif

2006 - http://weather.unisys.com/archive/sst/sst_anom-060521.gif 2005 - http://weather.unisys.com/archive/sst/sst_anom-050522.gif 2004 - http://weather.unisys.com/archive/sst/sst_anom-040516.gif 2003 - http://weather.unisys.com/archive/sst/sst_anom-030525.gif The dates aren't an exact match granted (these are the closest I could find in the archives list though) - but from a Sea Surface point of view things are definitely cooler than recent years at this point in the year. This seems a bit strange though really given the warmth across the N Hemisphere so far this year. Anyone have any theories on that? It will be interesting to see how they look in a month's time - will we get the normal summer warm up of recent years. 1995 GP? I'd take the summer and the winter - although the winter wasn't amazing down here from a snow point of view - although i know a lot of people did very well that season.

http://weather.unisys.com/surface/sst_anom.html Is it me, or is the North Atlantic cooling quite rapidly (relative to the average) at the moment? Still looks reasonable for a negative NAO forecast from the MO based on the surface temps anyway.

Here's my punt. 15.4c (above average due to cloudy nights and warm local sea surface temperatures) A very wet month with low pressure either over the UK or just to the W/SW. Possibly hot at times in the South East - but below average in the far NW. With hot air to the East and low pressure clashing over or around the UK, there's obviously the possibility of thunderstorms too. The most notable aspect of the month will be the rainfall though and this could cause problems. Basically I'm expecting the trough that's been around the UK in May to persist through June, but due to warmer air becoming available and sucked into the system from the East, rainfall intensity is likely to be higher than May.