May 1996

[damianslaw]

In view of the cold start to May 2010 and prospects of a fairly lengthy period ahead with sustained below average temps, I am remembering back to our last proper cold May i.e. 1996. May 1996 saw the CET finishing 2 degrees below normal. The first two thirds of the month was dominated by an airstream from between north and east from a cold source, I think the North Sea was particularly cold that spring due to the cold winter. We have very similiar synoptics this year to what we saw in 1996 with northern blocking in residence and we also have a cold North Sea and cold continent relative to recent years.

I vividly remember the spring being a very slow growing season much like this year.

Anyone else have recollections of May 1996.

[AderynCoch]

Freezing cold. I only really started following the weather about a year previous when May started off very warm (I don't remember it going cold afterwards though) and the following summer was an all-time classic, so it came as a shock to my young senses when May 1996 came round.

It was really the last exceptionally below-average month we've had, ranking alongside the coldest Mays on record: it lies joint 13th in the entire CET series, which makes it as noteworthy historically as January & December 1879.

[Optimus Prime]

Mean Maxima 13.4c (-2.2c below 61-90 average) Ranked 7th from 1878

Mean Minima 4.8c (-1.9c below 61-90 average) Ranked 2nd from 1878

CET tracker from 1st - 31st;

8.6

7.9

7.5

6.9

6.8

6.9

7.1

7.0

6.9

6.9

6.9

7.1

7.2

7.4

7.5

7.3

7.2

7.1

7.1

7.3

7.4

7.6

7.8

7.9

8.1

8.2

8.3

8.4

8.6

8.9

9.087

It was so close to the coldest May of the century. Had it not been for the last 3 days averaging 15.5c it would have been broken.

I don't quite agree AderynCoch, December 2009 and January 2010 were both more than 2.0c below normal;

December 2009 Mean Minima 0.4c which is joint 22nd lowest on record

December 2009 Mean Maxima 5.8c 29th lowest on record

January 2010 Mean Maxima 3.7c joint 15th lowest on record

January 2010 Mean Minima -0.9c 15th lowest on record.

[AderynCoch]

I don't quite agree AderynCoch, December 2009 and January 2010 were both more than 2.0c below normal;

December 2009 Mean Minima 0.4c which is joint 22nd lowest on record

December 2009 Mean Maxima 5.8c 29th lowest on record

January 2010 Mean Maxima 3.7c joint 15th lowest on record

January 2010 Mean Minima -0.9c 15th lowest on record.

2C below normal is much more common in December and January than in May, though still notable. January 2010 was notably cold but not exceptional; December 2009 was certainly not exceptional overall (except for parts of Scotland maybe).

Those max/min statistics only date back to 1878: in the same timeframe, May 1996 ranks 2nd lowest for average minimum and 7th lowest for average maximum. It is the 4th coldest May overall since 1878.

[Thundery wintry showers]

Surprisingly given how cold May 1996 was, snowfall was never as widespread as it was around 13-15 May 1993, 11-13 May 1995, or 6-7 May 1997. Unlike in many such instances, it wasn't down to consistent rather than outstanding cold, for in fact the cold snaps of 3-5 and 16-18 May 1996 saw comparably low temperatures to the 1995 and 1997 ones. I can only assume that less widespread shower activity and higher dewpoints played a significant role at the critical moments.

There was also a north-easterly incursion around the 10th-12th May 1996 which I remember well. I recall the BBC forecasts saying "turning increasingly showery in the east" for the afternoon of the 10th, and in reality, frontal cloud increased in Tyneside and there wasn't a shower in sight. The 11th was cloudy with showers, the 12th dull and drizzly.

In general the cold of the first two-thirds of May 1996 was down to repeated cold incursions from the north and north-east, while the last third had westerly winds and near-average temperatures except for a brief southerly on the 30th which saw the first instance of widespread maxima above 20C.