May CET

[Snowyowl9]

Theres been no below average mays since 1996 which is surprising,considering how cold of a snap we had in May 1997.

It does make May 1996 exceptionally cold though at just 9.1c 2nd coldest after 1902 somehow I can see it getting 10c maybe 9.9c this month and the first below average since then as this pattern does look prolonged at the moment.

Edited May 3, 2010 by Snowyowl9

[Thundery wintry showers]

May 1997 was not cold overall because it had alternating warm/hot and cold spells which cancelled each other out over the course of the month- the same was also true of Mays 1993, 1995 and 2005. May 1995 had the sharpest contrast, from maxima of 24-27C in the first week to wintry showers from the Midlands northwards in the second week, but May 1997 was arguably the most "episodic" of the lot, with a cold spell around the 20th-23rd as well as the famous northerly of the 5th-7th, offset by warm spells around the 1st-3rd, 16th-19th and the last few days.

May 1996 ended up very cold because of the unusual persistence of northerly and north-easterly winds in the first two-thirds, and then in the last third when winds were westerly, temperatures merely returned to normal.

[Stu_London]

CET dropping like a stone

8.6C to the 3rd

Perhaps sub 8 by the 10th isn't so outrageous a projection

[reef]

CET dropping like a stone

8.6C to the 3rd

Perhaps sub 8 by the 10th isn't so outrageous a projection

The minimum last night on Hadley is down as 1.5C, shaving 0.9C off that value alone. Looking like a very cold first half of the month, especially if the northerly occurs.

[stewfox]

The minimum last night on Hadley is down as 1.5C, shaving 0.9C off that value alone. Looking like a very cold first half of the month, especially if the northerly occurs.

Isn’t a North Easterly likely to settle in by the weekend, however with more cloud cover the mins may not get so low

Def sub 9c by the 10^th me thinks

[damianslaw]

Certainly a cold start to the month is on the cards, the airstream is set for at least the next 7 days to be between NW and East, meaning below average temps for the foreseeable future.

However, as we saw with this March a cold first half to a month can be cancelled out by a mild second half.

But have to say I would be very surprised if this May ends up 1 degree above the norm given the outlook and even 1 degree would take a notably very warm spell in the seconf half. Given the outlook we could be about to experience our coldest May since 1996.

[The watcher]

12.1c for the watcher...

[RichardR]

12.1c for the watcher...

Watching too much tele-vision most likely.

It will be interesting to have a May colder than 1996. Cold Mays can bring lots of convective showers and storms and hail. May 1983 (wasn't around) was like that, with lots of days of thunder 5-10 in many places. Shame we can't have that.

Edited May 4, 2010 by RichardR

[Weather-history]

The first half of May 1902 is the benchmark for chilliness with a CET of only 6.7C by the 15th

[SteveB]

8.3c to the 4th, -1.4c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[Stu_London]

8.3c to the 4th, -1.4c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

A much milder night last night (6.1C) so tomorrow may see a small rise. Further falls can't be ruled out before half way however with a rather cyclonic outlook persisting

[kold weather]

It does seem like at least till the 12th we have a decent shot at staying below 9C though cloud cover could raise it up just a little above it by the end of the weekend. Still a below average month is very much possible, esp if the ECM idea is correct...which in that case we'd be well below average right upto the 15th at least...

Going to need a big correction if thats the case, however unlike back in March I'm not sure the synoptics will favour a big climback, even if the 2nd half is somewhat warmer.

[summer blizzard]

Certainly looking like a well below average first half of May, though GFS FI does indicate the trough will back west with associated pressure build over western Europe and this has been showing for a few runs now.

[AderynCoch]

Well bang goes another CET prediction for me, barring a significant warm-up in the second half of the month (11.8C). Still, sub-10C is always going to be difficult even if we reach the halfway mark as progged.

[SteveB]

8.6c to the 5th, -1.2c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[SteveB]

9.0c to the 6th, -0.9c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[kold weather]

Still looking cool till at least the 15th, so we are going to go into the midway point probably close to 2C below average and thus we are going to need a decently warm 2nd to put it back upto average.

Given the set-up progged, I can't really see anything other then below average, even if the cool weather goes away, its not exactly looking that mild based on the pattern we are starting to see show up.

[Optimus Prime]

I've always noticed warm weather creeps in from around 162 hour mark slowly. Don't let your guard down lol.

[kold weather]

There is a chance that it will OP, but that being said the global synoptics are quite strong right now, its certainly the strongest signal in the Atlantic since the huge -ve NAO in Dec-Jan IMO, we have an upper high parked to our west which is at times going to allow a more average temps to come down. Any reload will just bring down another wave of cool NE airflows.

I think, at this early stage I'd say we are pretty much certain already to have the coolest May since 1996, granted that may not be that difficult given the coolest was only a smidge below normal.

[damianslaw]

Next 7 days look like delivering consistently well below average temps, consequently I can't see the CET rising much at all from where it is by mid month, maxes of 10-12 in CET zone and mins 4-6 degrees look the order of the day, some sheltered western parts could see maxes up to 14 degrees, but conversely mins will creep down to the 2-3 degrees. Scotland looks particularly cold with sub 528 dam creeping into northern england, the upcoming synoptics suggest the coldest spell of weather relative to average since first week of March and quite possibly second week of January. Coldest first half to May since 1996 is looking increasingly likely..

[Thundery wintry showers]

To be pedantic I thought 2005 was a smidge above normal - 11.4C CET as compared with the 1971-2000 normal of 11.3C. 1997 was next closest at 11.7C.

[SteveB]

9.0c to the 7th, -0.9c

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[Thundery wintry showers]

Considering the general mood on this forum you'd have thought we were staring at anomalies of -2.9C not -0.9C! It does look like dropping some more over the coming week though, mainly due to colder nights.

The low sunshine (64% for 1-5 May over England & Wales according to Philip Eden) may be contributing to the sense of a cold month.

[damianslaw]

Considering the general mood on this forum you'd have thought we were staring at anomalies of -2.9C not -0.9C! It does look like dropping some more over the coming week though, mainly due to colder nights.

The low sunshine (64% for 1-5 May over England & Wales according to Philip Eden) may be contributing to the sense of a cold month.

Yes granted compared to the rolling average at this point in May we are not recording a susbtantially below average start to May, however, given the upcoming synoptics I suspect the difference between the rolling average and what we have come mid month will be quite significantly below average at least -1.5 degrees below possibly close to 2 degrees. The latter part of May on average does tend to be appreciably warmer than the first week of May, but I believe it will be a long uphill struggle to get close to near average by the months end, it will take a sustained very warm period to do this, could happen but doubt it.

[Stormyking]

9.0c is really cold for May, though i still reckon it will end up near average by the end of the month