Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

--
Spud

On Wednesday, August 2, 2017 at 9:22:39 AM UTC+1, wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

--
Spud

You're not imagining it.

Skybus from Lands End to Scilly are having a terrible year of flight cancellations due to cliff top fog & warm sector mist.

I noticed on teletext the MetO said Shetland was sunnier than Cornwall in July, quite possibly. What amused me though was the precise figure for sunshine (153.3 hours IIRC) for a the whole of Cornwall County of moorland, opposite facing coasts, 100 mules from near Bude to Lands End. Given the unsettled nature of the month, I suspect that it ranged from approx just over 100 hours over some inland moors, and areas badly affected by the regular sea breeze convergence cloud which occurred during the month (Camborne did really badly for this reason), to 200 hours on some favoured headlands. For what it's worth there was 184 hours on the moors behind Penzance, about 90% of normal for that spot, so must have been 200 hours in Penzance.

Graham
Penzance

On Wed, 2 Aug 2017 01:38:51 -0700 (PDT)
Graham Easterling wrote:

On Wednesday, August 2, 2017 at 9:22:39 AM UTC+1, wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

--
Spud

You're not imagining it.

Skybus from Lands End to Scilly are having a terrible year of flight
cancellations due to cliff top fog & warm sector mist.


The specific humidity has been high but not always the relative humidity. RH
always goes up at night of course.

Will
--



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On Wed, 2 Aug 2017 01:38:51 -0700 (PDT)
Graham Easterling wrote:
On Wednesday, August 2, 2017 at 9:22:39 AM UTC+1, wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is th=
is
actually the case or am I imagining it?
=20
-- =20
Spud

You're not imagining it.

Skybus from Lands End to Scilly are having a terrible year of flight cancel=
lations due to cliff top fog & warm sector mist.

Is this down to the atlantic surface waters being warmer than normal (I don't
know if they are) or some other factor?

--
Spud

In message , d writes
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?


Here in a fairly rural part of Surrey I've not noticed any difference.
In previous years, when it's been hot it's mostly been too humid to be
comfortable, and this summer's been the same. Why it's been blessedly
cool, as over the last week or two, it's not seemed particularly humid
apart from the occasional day.
--
John Hall
"Three o'clock is always too late or too early
for anything you want to do."
Jean-Paul Sartre (1905-1980)

On Wednesday, August 2, 2017 at 10:09:21 AM UTC+1, wrote:
On Wed, 2 Aug 2017 01:38:51 -0700 (PDT)
Graham Easterling wrote:

On Wednesday, August 2, 2017 at 9:22:39 AM UTC+1, wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

--
Spud

You're not imagining it.

Skybus from Lands End to Scilly are having a terrible year of flight
cancellations due to cliff top fog & warm sector mist.


The specific humidity has been high but not always the relative humidity. RH
always goes up at night of course.

Will
--



---
This email has been checked for viruses by AVG.
http://www.avg.com

The RH has been significantly high overall here.

I was speaking to someone at Skybus (I used to work for them) and this summer is set to break the record for flights cancelled due to fog (from Land's End), often of the warm sector / cliff top variety, rather than sea/coastal fog. They don't fly at night (Flights from approx 08:00 to 20:00). There have been several days with no flights whatsoever, including 1 day I was booked on.

No flights today again view towards the airport from Sennen http://www.sennen-cove.com/harbourcam.htm

In partial answer to Spud, the offshore SST was way above normal May to mid July, 18C-19C even out at Sevenstones early July, and I recorded 17C off the Battery Rocks Penzance in May, shattering what I'd recorded at that time of year before.

It has dropped back to near normal now, with the very disturbed conditions increasing the mixing. http://polar.ncep.noaa.gov/sst/rtg_l...maly_oper0.png .

Graham
Penzance

On 02/08/2017 09:22, d wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

Dew points give a good indication to how 'humid' it feels and the
following are the average maximum daily dew points for here from 1st
June - 31st July:

2015 = 15.2C
2016 = 17.0C
2017 = 16.8C.

So yes, this summer has been 'humid' but slightly less so than last
year, though last year the weather often did feel quite oppressive at times.

Certainly humid today, temp = 18.3C, DP = 18.3C; drizzle.

--
Nick Gardner
Otter Valley, Devon
20 m amsl
http://www.ottervalleyweather.me.uk

On Wed, 2 Aug 2017 19:22:43 +0100
Nick Gardner wrote:

On 02/08/2017 09:22, d wrote:
Perhaps I'm wrong, but to me this summer seems to have been constantly
humid down here in London regardless of temperature or cloud cover. Is this
actually the case or am I imagining it?

Dew points give a good indication to how 'humid' it feels and the
following are the average maximum daily dew points for here from 1st
June - 31st July:

2015 = 15.2C
2016 = 17.0C
2017 = 16.8C.

So yes, this summer has been 'humid' but slightly less so than last
year, though last year the weather often did feel quite oppressive at times.

Certainly humid today, temp = 18.3C, DP = 18.3C; drizzle.


Dewpoints are of course related to specific humidity. Relative humidity will
vary a lot both diurnally and in precipition of course. A temperature of 10C
with a dewpoint of 10C will give the same RH as a temperature of 20C with a
dewpoint of 20C. But the specific humidity at 20C is considerably higher than
that at 10C.

Will
--

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