[Pete Roberts]

The temperature of inland water bodies is a good representation of long-term average temperatures and insolation as the thermal inertia of large water bodies smooths out short term fluctuations.  Given that I swim outdoors almost daily and all year round I'll be recording my water temperature readings here.

Hatchmere (Lake), Delamere Forest, Cheshire, 22-6-10: 23C

 Pete

 

 

[Pete Roberts]

River Weaver, Frodsham, Cheshire, 23-6-10: 23.7C

A little high for June but certainly not unusual. Not comfortable for swimming any distance though.

Pete

[Pete Roberts]

R. Weaver, Frodsham, 25-6-10: 23.5C

Temperature taken using my spirit-in-glass pool thermometer as my electronic thermo has been loaned to a friend to monitor his tropical fish tank temp. Both instruments (made by Brannan) have been checked and accurate to less than 1C error @ 0C.

Pete

[Pete Roberts]

River Weaver, Frodsham, 29-6-10: 25C on spirit thermo.

Last night's rain has dispersed the algae from the river but hasn't done anything to cool the water.

Pete

[Matt D]

What depth are you measuring the water temp Pete?

[Pete Roberts]

Quote

Matt D - 29/6/2010 19:09 What depth are you measuring the water temp Pete?

When using the spirit thermo I measure the temp at 400mm depth as recommended by FINA*

Bear in mind that in a flowing river, even a sluggish one, turbulence mixes surface and deeper water.  The Weaver has never to my knowledge had a thermocline at any time of the year.

Pete

*FINA, the Fédération Internationale de Natation, is the world governing body for the five aquatic disciplines of swimming, diving, water polo, synchronised swimming and open water swimming (but not my discipline: winter swimming).

[Paul Domaille]

Fascinating figures Pete, as an Islander I had no idea inland water temps reached so high.

Cheers,

Paul D

[Pete Roberts]

R. Weaver, Frodsham, 30-6-10: 26C

Pete

[Pete Roberts]

R. Weaver, Frodsham. 1-7-10: 23.5C

Overnight rain in the catchment seems to have resumed normal flow and slightly reduced water temp.

Pete

[Pete Roberts]

River Weaver, Frodsham, Cheshire 5-7-10: 23.5C

Although I swam in the river on Saturday I forgot my thermometer.

Pete

[Pete Roberts]

After two days of laziness I actually motivated myself today to go for a swim.

River Weaver, Frodsham, 8-7-10: 24C

Pete

[Dave W]

Went in the sea today at Shoreham.. really warming up now.. it felt a bit like bath water in the shallows! More med like than Ive felt here for years..

[Pete Roberts]

River Weaver, Frodsham, Cheshire 10-7-10: 23.5C

Pete

[Pete Roberts]

Hatchmere, Delamere Forest, Cheshire 11-7-10: 22C

This was the site of one of today's pan-European "Big Jump" swims.

Pete

[Pete Roberts]

River Ouzel, Willen Road Bathing Place, Newport Pagnell: 21C

Pete

[Pete Roberts]

River Biam, Aylestone Meadows, Leicester, 14-7-10: 17C

Pete

[Pete Roberts]

River Weaver, Frodsham, 19-7-10: 22.5C

This is despite a fairly stiff current indicating significant rainfall in the catchment.

Pete

[PK2]

Curious the rivers around Frodsham are warmer that those in Leicester. I'd have thought river temps would be warmer in the east ATM given the past few weeks of cloud and rain (at least along the coast into Wales)

[Pete Roberts]

Quote

PK2 - 19/7/2010 16:31 Curious the rivers around Frodsham are warmer that those in Leicester. I'd have thought river temps would be warmer in the east ATM given the past few weeks of cloud and rain (at least along the coast into Wales)

Depends on the source.  Many rivers are fed from springs but others, such as Cheshire's R. Weaver,  are fed by surface water which in summer is much warmer.

 Pete

[Pete Roberts]

River Lune, Kirkby Lonsdale (Devil's Bridge), Lancaster, 22-7-10: 16C

River running fast and peaty from recent rain.

Pete