In uk.sci.weather on Sat, 2 Jun 2007, Stephen Burt
wrote :
On 2 Jun, 18:18, Paul Hyett wrote:
What would be a ball-park figure for the average difference between it &
the screen minimum value?
--
Paul Hyett, Cheltenham (change 'invalid83261' to 'blueyonder' to email me)

Varies hugely with conditions, location and season. A common value
would be 2-4 degC but sometimes 0 degC, very occasionally 7-10 degC.

Thanks - that is pretty much in line with my readings.
--
Paul Hyett, Cheltenham (change 'invalid83261' to 'blueyonder' to email me)