On Tuesday, 14 January 2014 13:33:35 UTC, exmetman wrote:
Hi Last year I developed a method of estimating snowfall from looking at the daily Central England Temperature and England Wales precipitation series. I thought it made a fairly good stab at producing a Central England Snowfall series and one of the weather events it highlighted was the bitterly cold period in January 1987. I thought then I would blog in more detail about what I remembered - It’s hard to believe that all happened 27 years ago! My estimate using that method was for 7.1 cm of snow for the 11 January 1987 making it the 21st snowiest day in Central England since 1931, but that was way of the mark for Louth in Lincolnshire where we lived at the time, and I can still remember quite clearly over 30 cm of the lightest powder snow accumulating during Sunday the 11th. There hadn't been a lot of wind initially, but when I tried to motor into RAF Binbrook to start a day shift on the Monday morning, the wind (which must have picked up around dawn) had cleared all the snow from the fields and dumped it on all the lanes that crossed the wolds, that snow lasted for weeks (see image). As you can imagine I didn't make it in for the day shift and the observer who started out doing the Sunday night shift ended being there till the following Saturday. I now have the SYNOP charts to look at this week in more detail, and I also have the upper air data for this year, but I still have to extract it from DVD and build an archive before I can fully access it. I've attached the 1000-500 hPa thickness chart (hand drawn from the Molfax chart at the time) just to give you an idea how cold this air really was, forget the blue 528 line, forget the brown 510 line, this was purple 498 thicknesses, at least for a time before the cold pool warmed out as it drifted westward, because amazingly warmer air did chased it away from the east if I remember correctly, and by Thursday surface temperatures where recovering to above 0°C. Finally I've included an animated plotted chart for the east of England for the main synoptic hours. I suspect that the intensity of the cold air over England and Wales was not matched by any other day in the 20th century, but I don’t have the upper air records to prove that conclusively, hopefully one day, the Met Office will make this upper air data available online to see if I’m right! Bruce. (1) 1200 UTC plotted UK SYNOP charts for 9-17 January 1987 (2) 1000-500 hPa thickness for 13 Jan 0000 UTC (3) Eastern England plotted animation 10-15 Jan 1987 (4) January 1987 Synoptic charts http://xmetman.wordpress.com/2014/01...-january-1987/

The total precipitation here during that cold spell was 33 mm, all of it snow and the maximum depth was 39 cm. The serious snow fell on the evening of the 12th and during the 13th and fell from cloud so thin you could see the moon through it. Snow depths on the Downs of Kent and east Surrey were up to about 4 feet. The temperature here was below 0°C for over 10 days and the lowest max was -9.2°, a figure I could hardly believe.

There is one precedent that I know of, that of 1 Feb 1956, when the thickness was also down to 498. Purple is 492, BTW, or 582 if you prefer. A bit much, either of them. :-)

Tudor Hughes, Warlingham, NE Surrey, 556 ft.