On Tuesday, July 3, 2018 at 9:14:48 AM UTC+1, Graham Easterling wrote:
A very unstable day yesterday with a fair bit of cloud (which made a real change!) including sizeable Cb from late morning.

There was quite sizeable surf yesterday for the 1st time for week. I went out to Sennen (it was plenty big enough for me) and there was some interesting weather.

10:30
F3 offshore E wind sunshine, 23C or so.

11:00
A feature heading in from the east backed the wind, and together with a sea breeze influence it became a distinctly F4-5 alongshore NNE. Strong enough to create white horses & whip the top of the breaking waves. At the same time this air (now 20-21C or or so on the beach) came up against air near 25C just inland, and within minutes quite large CU had formed a mile or so inland.

12:00 The sea breeze pulse died & the wind veered E. The band of Cu & Cb passed overhead and there were a few large drops before the sun came out and the temperature rapidly rose.

During the afternoon, the sea breeze against a now generally E flow caused convergence along the north coast. A series of heavy showers ran westwards near the north coast, with some thunder. Little rain onshore.

All fell calm in the evening and it was very muggy. 22C @ 21:30.

Endlessly interesting, the weather & sea.

Graham
Penzance (Yesterdays Max 25.8C)

No such marked variations at Sennen today. Just got back. An offshore ESE F2-3 fell near calm from 11:30 to 13:30, when a left. Just an occasional tendency for an onshore sea breeze, but it was minimal, just a F1 alternating with a F1-2 offshore, indicated by the flags marking the swimming / surfing area. Temperature around 25C & near unbroken sunshine from 11:00-13:30. It was really quite hot in the strong sunshine.

Unlike yesterday very little surf, which is a shame as I'm heading up to England tomorrow.

Patchy thin Sc now starting to arrive from the east and the temperature is starting to dip. Cloud arrived at Sennen at 14:10 - going by today's webcam stills. https://magicseaweed.com/Live-Sennen-Webcam/65/

Graham
Penzance