"souwestdad" wrote ...
snip
The important thing is that the rainfall day data is correct.
At unattended automatic stations very little can be done until the
snow melts. The accumulated readings of snowmelt are then re-
allocated to the correct rainfall days by comparing with the nearest
climate stations or manned Met sites.
So, although it may not be the case until some weeks after the
event,
the readings are eventually accurate.

..... er, no. Hardly accurate. Imagine an AWS gauge that has been left
for three weeks with *significant* (as in the case of Aviemore) snow
building up event-on-event, being added to by fresh falls, taken away
by wind scouring, removed by sublimation, blowing over the top without
accumulation etc., etc.

The only way to get an *approximate* idea of the water equivalent of
snow is to monitor the situation, at least once per 24hr, and
preferably more frequently, with slices taken of new snow to melt,
giving the current-event water-equivalent, which can then be added to
the previous assessment etc. It's a tedious, time-consuming process,
and a jolly cold one!

Reality kicks in these days of course - there are fewer manned
observing stations (at least professionally), which is why the 'hobby'
network is so important.

Martin.



--
Martin Rowley
West Moors, East Dorset (UK): 17m (56ft) amsl
Lat: 50.82N Long: 01.88W
NGR: SU 082 023