"John Hall" schreef

: Colin Youngs writes:
: I was thinking particularly of the fall from 27°C to -1°C less than 24
hours
: later ... and 19°C to -11°C at Abilene
: http://weather.noaa.gov/weather/current/KABI.html

: The latter is actually a fall from 19F to -11C, which is considerably
: less impressive. You have to be careful with the units with US sites.

Indeed you do, but, at the time I looked yesterday evening, there had been a
fall from 19°C to -11°C within 24 hours. The 19°C reading has now dropped
off the bottom of the list !

Colin Youngs
Brussels