"Jon O'Rourke" wrote in message
...
"Dave Cornwell" wrote in
message newsdAdo.13666$_s6.9201@hurricane...
I've been aware that the rainfall radar is less accurate for fine rain
but today has really puzzled me. It was pouring down from at least 10 a.m
till 8p.m in East Suffolk today and everywhere else that I drove through
down the A12. It was quite fine rain but enough to cause flooding on the
side roads. When I got home and looked at the day's radar there was only
some patchy light blue echos around. It probably seemed worse as I was
out in it and it contradicted the mainly dry overcast forecast for the
region but I would be interested in any rainfall figures for somewhere
near RSPB Minsmere.

Dave.


Dave, as you say the fine rain/drizzle is often the reason for the radar
to under-read but another factor could well be the distance from the
nearest radar. There's a bit of a gap over Norfolk and Suffolk in terms of
high resolution radar coverage but this should change if/when the proposed
radar at Old Buckenham comes online.

Current radar network
http://www.metoffice.gov.uk/weather/...verage_med.gif

The revised network including Old Buckenham can be seen here on page 6
http://www.metoffice.gov.uk/corporat...actsheet15.pdf
and pages 13-16 detail the possible causes of error which may be of
interest (figure 16 on page 13 could well apply today).

Jon.
----------------------
Thank you for the excellent and interesting reply, Jon. I think I may have
been on the right lines and reading this makes a lot of sense. As well as
being that persistent but heavy fine rain - you know the sort that seems to
soak you the most ;-( it did seem to be coming from very low level cloud.
The visibility was very poor and you could see the low cloud swirling around
much as you can when in mountain rain of this type. So I guess it was a
combination of height and distance. I found a station that gave Ipswich with
30mm and a friend on the North Norfolk coast got 44mm in the 24 hour period.
Also what a wonderful fact sheet.
Cheers, Dave.

www.laindonweather.co.uk