Longest Wait In Year For 1st 20oc

[Weather-history]

What would be interesting is if we didn't record 20C in both June and July, and possibly August.... sounds ridiculous, but is it?

It would be interesting to know if this has ever happened, where 20C hasn't been recorded in summer in England in a particular location - I dont think it's beyond possibility - though very unlikely, given recent history.

1860 would be my year for the strongest possibilty. That was a very cold year.

The highest maximum for 1860 at Greenwich was just 76.5F (24.7C) on the 23rd of May.

And at Camden Square, it was 76.1F (24.5C)

So 25.0C was a very scarce reading during 1860, it certainly wasn't recorded at two London weather stations, where it shouldn't be that too difficult to achieve.

The year before (1859) 80F+ was recorded on 34 occasions at Greenwich

Edited May 17, 2009 by Mr_Data

[SP1986]

Thats very interesting thanks!

It is possible (I suppose) that this year whilst not too cold/cool, will lack high temperatures..

I think now my interest has meandered away from a hot summer, and I'm actually interested in how low our maximum temperatures can stay throughout the summer! Mind you it only takes one hot spell!

[Snowyowl9]

1991 was a strange year indeed. We reached 20C just 5 times before 1st July (21.4C being the highest), but then from 1st July - 17th September just 12 days failed to reach it. It was almost like a switch was flicked at the end of June.

Yes 1991 was a good summer.

As for June it`s a month like this, temp only reached 16c max 2 days at the end.

http://www.wetterzentrale.de/archive/ra/19...00119910630.gif

Edited May 17, 2009 by Snowyowl9

[Higher Ground]

What would be interesting is if we didn't record 20C in both June and July, and possibly August.... sounds ridiculous, but is it?

It would be interesting to know if this has ever happened, where 20C hasn't been recorded in summer in England in a particular location - I dont think it's beyond possibility - though very unlikely, given recent history.

Where's the last place you'd think of??!!.............

How about the Scilly Isles....... seems it came pretty damn close there the last couple of summers:

2008: 20C+ only recorded on 3 days, highest max ~21C

2007: 20C+ only recorded on 4 days, highest max ~20.5C

So if you still think in Fahrenheit, although it's touched 70F (21.1C) on one day it hasn't been "into the 70s" there (in anything more than an academic sense) since 2006!

It therefore seems almost a dead cert there must have been a summer in recent decades when 20C wasn't recorded there? Given the warming of the North Atlantic....?

Edited May 17, 2009 by Higher Ground

[SP1986]

Where's the last place you'd think of??!!.............

How about the Scilly Isles....... seems it came pretty damn close there the last couple of summers:

2008: 20C+ only recorded on 3 days, highest max ~21C

2007: 20C+ only recorded on 4 days, highest max ~20.5C

So if you still think in Fahrenheit, although it's touched 70F (21.1C) on one day it hasn't been "into the 70s" there (in anything more than an academic sense) since 2006!

It therefore seems almost a dead cert there must have been a summer in recent decades when 20C wasn't recorded there? Given the warming of the North Atlantic....?

Possibly but I suppose it's normal given it's location as an island. Of course where the Isles of Scilly lack warmth in summer, they positively retain it in winter. Isles of Scilly rarely every drop below 4C at any time during winter, day and night, so that's quite a benign climate - almost subtropical-like. Just not warm or sunny enough in summer to fulfil that though! Still it probably records the one of the highest annual temperatures in the UK on average despite it's summer cool nature.

[damianslaw]

What hasn't helped so far this spring in delivering 20 degrees to many has been the absence of import of continental air from europe, much of our weather has been 'homegrown' so to speak i.e. we have not been tapping into any air from a source with a long draw from any real direction - take now for instance we have a low pressure anchored very close to us, the air wrapped around it is in a closed circulation and is not tapping into air source from any great distance so to speak, high pressure when it has appeared again has done much the same.. It would be a very poor show for May if we don't see 20 degrees at any point - quite dissapointing..

[Higher Ground]

Possibly but I suppose it's normal given it's location as an island. Of course where the Isles of Scilly lack warmth in summer, they positively retain it in winter. Isles of Scilly rarely every drop below 4C at any time during winter, day and night, so that's quite a benign climate - almost subtropical-like. Just not warm or sunny enough in summer to fulfil that though! Still it probably records the one of the highest annual temperatures in the UK on average despite it's summer cool nature.

Well I thought it came pretty close to what you were looking for in your question. 2007 and 2008 seem to have had the least maxes above 20C for St Mary as far back as those Weatheronline records go (1996). Also, average August max there was 19.4C for 1996-2008 so the normal average max is actually quite high, albeit there obviously tends to be a small range because of the island location. All it takes is a few days of settled weather and 20C ought to be broken, but I guess these were in short supply the last couple of summers. (I guess it got warm over the mainland when there were warm winds from the continent, rather than prolonged settled conditions?)

[Costa Del Fal]

Im sure most places in Central & South Midlands and most of Southern England have exceded 20c so far-i know i have!

[Summer of 95]

Well I thought it came pretty close to what you were looking for in your question. 2007 and 2008 seem to have had the least maxes above 20C for St Mary as far back as those Weatheronline records go (1996). Also, average August max there was 19.4C for 1996-2008 so the normal average max is actually quite high, albeit there obviously tends to be a small range because of the island location. All it takes is a few days of settled weather and 20C ought to be broken, but I guess these were in short supply the last couple of summers. (I guess it got warm over the mainland when there were warm winds from the continent, rather than prolonged settled conditions?)

According to Trevor Harley's site, at Land's End in July 1988 it didn't reach 16C all month 1988_weather

Which I'd think is extraordinary for somewhere like Aberdeen in July, let alone the warmest corner of Britain. I suppose that a non-stop flow of wind off the Atlantic (ie a continuously cyclonic/westerly month) meant the temperature couldn't rise far above the temperature of the sea despite what I suspect were fairly high minima- that would fit for much of summers 2007 and 2008 as well.

[Higher Ground]

According to Trevor Harley's site, at Land's End in July 1988 it didn't reach 16C all month 1988_weather

Which I'd think is extraordinary for somewhere like Aberdeen in July, let alone the warmest corner of Britain. I suppose that a non-stop flow of wind off the Atlantic (ie a continuously cyclonic/westerly month) meant the temperature couldn't rise far above the temperature of the sea despite what I suspect were fairly high minima- that would fit for much of summers 2007 and 2008 as well.

Great stat/link re: July 1988 - thanks!

I note that the NE Atlantic SST Anomalies are pretty cold at the moment......

(As also indexed by the AMO)

[Derp Patrol]

We've already hit 20C at least 5 or 6 times :lol:

[J07]

Possibly but I suppose it's normal given it's location as an island. Of course where the Isles of Scilly lack warmth in summer, they positively retain it in winter. Isles of Scilly rarely every drop below 4C at any time during winter, day and night, so that's quite a benign climate - almost subtropical-like. Just not warm or sunny enough in summer to fulfil that though! Still it probably records the one of the highest annual temperatures in the UK on average despite it's summer cool nature.

Yes you can see the lack of diurnal and annual variation here:

http://www.wunderground.com/NORMS/DisplayI...mp;Units=metric

Quite a contrast to the mainland, having only 12 days in January and February that fell to 4C or below, and only one air frost.

If that is correct then we have an average annual high of 12.3C, and an annual average low of 10.3C - giving an annual mean of 11.3C. I think we can be quite sure that is the highest annual mean of anywhere in the UK. That is the same mean annual temperature as the Chatham Islands - which lie about 1000km nearer to the equator, but in the path of a cold current.

[Norrance]

17.3C is my maximum so far this year on the 20th April. All the Easterly winds are keeping it cool on the East side of Scotland while bringing some sunshine and warmth to the North West.

Last year we did get over 21C on the 10th of May so this year is definately later. No cold minima either this Spring but some supressed maxima in the last couple of weeks.

[johnholmes]

this May, so far, here, is way way below 2008

it had 11 days of 21C and above

and I made this comment at the end of the month

5-12th inclusive= mean of 17.0C also longest ever for any records in May with > 22c=8 days and also 4>25C

this year, so far the warmest is the 1st with 19.6C

April had one day this year of 21C+

[Snowyowl9]

Great stat/link re: July 1988 - thanks!

I note that the NE Atlantic SST Anomalies are pretty cold at the moment......

(As also indexed by the AMO)

Atlantic does look below average.

[I remember Atlantic 252]

wont be long now, 20oC will be reached during whit holiday week, 25oC possible id say by 30th but long way off, today milder 18.9oC

[reef]

First date in the year to reach 20C in this location (1983-2009):

1988: Jun 19th

1986: Jun 13th

1983: Jun 7th

1985: May 26th

2001: May 22nd

2009: May 21st (Current Max 17.9C)

If we dont reach 20C tomorrow then it will be the latest date in the year to do so since 1985.

[Snowyowl9]

No danger of reaching 20c friday.

http://91.121.93.17/pics/Rtavn2417.png

Saturday could make the warmest day this month upto 17c

Sunday`s the day.

http://91.121.93.17/pics/Rtavn7817.png

[damianslaw]

I think we have a good chance of recording our first 20 degrees of the year on Sunday, it will be a close run affair, but it is plausible, however I don't think we will manage 21 degrees.. quite poor considering we are nearing the end of May even in what is not a very warm part of the country.

[Tucco]

I think we have a good chance of recording our first 20 degrees of the year on Sunday, it will be a close run affair, but it is plausible, however I don't think we will manage 21 degrees.. quite poor considering we are nearing the end of May even in what is not a very warm part of the country.

Looking at the latest forecasts it appears less likely now. Temps look to be in the order of 15/16 for sunday for far North England, which will be very pleasent.

GFS going for a air frost on Sunday night for North England.

Max temp for the month yesterday at 13.4C which felt very nice indeed, when the sun was out.

Mark

Teesdale,Co Durham

[TonyH]

You worry when summers dont reach 25c as happened in 1974 when i was a kid in Midlands! Anyway the warmth is now imminent.

[Stargazer]

Here in the heart of the south, of course, it would be unusual not to reach 20 deg C in May (I don't recall it happening in recent years) and it usually does at least once during April - this year has been no exception, and we have already had a handful of days above 20, the first of which was in mid April.

What is of note here is that we have had a typical number of days of 20+ but generally above average temperatures (albeit only just during May). This reflects the unusually low day-to-day temperature variations we have been experiencing - I haven't checked but I would expect to see that a surprisingly large number of days in April and May with the maximum close to 17 and the minimum close to 7 (with some variation taking account of the expected steady upward progression of temperatures during the two months). Basically a remarkable number of close to average daytime maxima and night time minima and few extremes.

Edited May 22, 2009 by Stargazer

[damianslaw]

Looking at the latest forecasts it appears less likely now. Temps look to be in the order of 15/16 for sunday for far North England, which will be very pleasent.

GFS going for a air frost on Sunday night for North England.

Max temp for the month yesterday at 13.4C which felt very nice indeed, when the sun was out.

Mark

Teesdale,Co Durham

Yes can't see us see us reaching 20 degrees tomorrow, perhaps 18 degrees if we are lucky. Maximum today was very close to the 16 degree mark, the wait continues, but very good chance I think that we will see 20 degrees later next week.

[Tucco]

Yes can't see us see us reaching 20 degrees tomorrow, perhaps 18 degrees if we are lucky. Maximum today was very close to the 16 degree mark, the wait continues, but very good chance I think that we will see 20 degrees later next week.

Max today 13.9C, best max on Sunday should be around 16C. Windermere should see 18C as you say. Chilly night ahead.

Mark

Teesdale,Co Durham

[SP1986]

not broken 20C still, and probably won't tomorrow either to be fair. Our one chance to break it is next week - if that doesn't happen either then I'm at a complete loss to when it will