Months with below 10mm rainfall

[Weather-history]

April 2007 has joined the club of months with less than 10mm for England and Wales since 1766

Months with below 10mm rainfall

Jan 1766: 4.4mm

Mar 1781: 5.6mm

Oct 1781: 8.8mm

Dec 1788: 8.9mm

Jul 1800: 9.1mm

Apr 1817: 7.9mm

Jul 1825: 8.2mm

Mar 1840: 9.8mm

May 1844: 7.9mm

Sep 1865: 9.5mm

Feb 1891: 3.6mm

Apr 1893: 9.9mm

Apr 1912: 9.0mm

Jun 1925: 4.3mm

Mar 1929: 8.0mm

Feb 1932: 8.9mm

Apr 1938: 7.1mm

Apr 1957: 9.7mm

Feb 1959: 8.7mm

Sep 1959: 8.0mm

Aug 1995: 9.1mm

Apr 2007: 9.3mm

It is the 4th driest April on record

1938: 7.1mm

1817: 7.9mm

1912: 9.0mm

2007: 9.3mm

[Angel15]

I hope it is not an indication of the months to come.

[johnholmes]

tks for that info Mr D

In your own inimimitable style are you able to relate these dry Aprils' to any particular weather pattern for the summer?

[Summer of 95]

Interesting figures, I make that 22 months in 341 years (average one every 15.5 years) distributed:

Jan 1

Feb 3

Mar 3

Apr 6

May 1

Jun 1

Jul 2

Aug 1

Sep 1

Oct 1

Nov 0

Dec 1

They seem to come in phases; despite averaging one every 15.5 years we had 4 in 13 years from 1766, and the same from 1925, then 3 in 3 years (and 2 in one year- 1959) in the late 50's. After that there were none for 36 years.

No Novembers then? And surprisingly few in the May-Sep period, especially with so many Aprils. I'm especially surprised there wasn't an August before 1995, and has been no May or July for over 160 years.

[johnholmes]

interesting summary there.

Statistics=lies damn lies and statistics

but are'nt they absorbing?

[Weather-history]

tks for that info Mr D

In your own inimimitable style are you able to relate these dry Aprils' to any particular weather pattern for the summer?

Driest Aprils on record and the following summer

1938: CET 15.3

1817: CET 14.3

1912: CET 14.3 August was wettest on record (192.9mm). I think it is the greatest difference in rainfall totals between two months in the same year.

2007: ?

1957: CET 15.6

1893: CET 16.5

1785: CET 15.4

1984: CET 16.3

1854: CET 14.6

1974: CET 14.8

1842: CET 15.7

A mixed bag.

[johnholmes]

tks for that, and as you say, 'a mixed bag'

[Nick H]

Interesting figures, I make that 22 months in 341 years (average one every 15.5 years) distributed:

Jan 1

Feb 3

Mar 3

Apr 6

May 1

Jun 1

Jul 2

Aug 1

Sep 1

Oct 1

Nov 0

Dec 1

No Novembers then? And surprisingly few in the May-Sep period, especially with so many Aprils. I'm especially surprised there wasn't an August before 1995, and has been no May or July for over 160 years.

I can't say I'm particularly surprised by that distribution, it's fairly common knowledge that Feb-Apr is the driest period of the year and Oct-Dec often is the wettest. August is known for heavy thorms too.

Edited May 8, 2007 by Nick H

[Terminal Moraine]

Interesting that, living in one of the wetter parts of central England, the only month on the list which is also on my own list of driest months is August 1995.

I would have expected that, allowing for the usual excess of rain here compared to the Central England sites, that the following months would have featured;

Sept'... 1986.........8.2mm here

May.....1991.........11.2mm here

April....1984..........11.6mm here

Feb'.....1993..........12.5 mm here.

Evidently in the very driest months the orographic influence is either greatly reduced or non-existent.

T.M

[summer blizzard]

Driest Aprils on record and the following summer

1938: CET 15.3

1817: CET 14.3

1912: CET 14.3 August was wettest on record (192.9mm). I think it is the greatest difference in rainfall totals between two months in the same year.

2007: ?

1957: CET 15.6

1893: CET 16.5

1785: CET 15.4

1984: CET 16.3

1854: CET 14.6

1974: CET 14.8

1842: CET 15.7

A mixed bag.

Not really, only three of those eleven were above average overall.

[johnholmes]

being a touch pedantic are we not SB?

Mr D said, I quote, 'a mixed bag'.

I cannot see that his comment is misplaced.

You say only 3 out of the 11 were above average, or just under 1 in 4, or put another way, 27%.

Seems about right the summary Mr D gave!

[summer blizzard]

being a touch pedantic are we not SB?

Mr D said, I quote, 'a mixed bag'.

I cannot see that his comment is misplaced.

You say only 3 out of the 11 were above average, or just under 1 in 4, or put another way, 27%.

Seems about right the summary Mr D gave!

True, but another 3 were at least 1C below average.

[johnholmes]

exactly the point he made,

a mixed bag, some above some below!

[summer blizzard]

My point was, 3 of 11 were above, 8 of 11 were below, 3 of those by at leat 1C.

[johnholmes]

have it your way young man

[Weather-history]

Sep 1865: 9.5mm

This is the strangest one of the lot

Aug 1865: 126.0mm

Sep 1865: 9.5mm

Oct 1865: 168.4mm

Bizarre!

Edited May 13, 2007 by Mr_Data

[johnholmes]

like you say very odd and must be perhaps the only one with such wet months either side, at any time opf the year?

[Weather-history]

like you say very odd and must be perhaps the only one with such wet months either side, at any time opf the year?

We've had drier months sandwiched between two wet months but it is the most extreme of its type.

A recent example is in 2004

Aug 156.5

Sep 49.8

Oct 154.9

A sub 50mm month sandwiched between two 150+mm months

[johnholmes]

had not realised there was one that recently.

[Weather-history]

Here's another gem

April 1782: 139.0mm

May 1782: 142.4mm

June 1782: 55.3mm

July 1782: 131.7mm

Aug 1782: 150.8mm

[Summer of 95]

July 1999 is the one I always remember as a dry month sandwiched between a load of wet months, looking at the EWP overall it does stand out but nothing near as well as Sep 1865:

June 90.9

July 26.3

August 116.6

Sep 124.9

Another one that I didn't think of but scanning the EWP and thinking back to it, it's a really good example- May 1998:

April 130.9

May 33.9

June 121.4

[Weather-history]

Here's the following month's rainfall totals in ()s

Jan 1766: 4.4mm (66.7mm)

Mar 1781: 5.6mm (55.6mm)

Oct 1781: 8.8mm (121.3mm)

Dec 1788: 8.9mm (105.6mm)

Jul 1800: 9.1mm (55.7mm)

Apr 1817: 7.9mm (101.4mm)

Jul 1825: 8.2mm (94.0mm)

Mar 1840: 9.8mm (24.2mm)

May 1844: 7.9mm (40.4mm)

Sep 1865: 9.5mm (168.4mm)

Feb 1891: 3.6mm (59.0mm)

Apr 1893: 9.9mm (45.8mm)

Apr 1912: 9.0mm (56.6mm)

Jun 1925: 4.3mm (81.3mm)

Mar 1929: 8.0mm (34.9mm)

Feb 1932: 8.9mm (59.7mm)

Apr 1938: 7.1mm (71.8mm)

Apr 1957: 9.7mm (44.8mm)

Feb 1959: 8.7mm (70.3mm)

Sep 1959: 8.0mm (90.7mm)

Aug 1995: 9.1mm (123.3mm)

Apr 2007: 9.3mm (50mm+)

The odds were stacked against this May being on the particularly dry side.

Edited May 14, 2007 by Mr_Data

[Somerset Squall]

had not realised there was one that recently.

Goodness yes, August 2004 was horrific down here (I did see my first funnel cloud though ). And I'm sure the residents of Boscastle remember it well.

[Metwatch]

Interesting to update this. 

This century so far no month in the EW region has had a sub 10mm month. April 2007 is at 10.4mm. Very rare to get one, only 20 months since 1766 with less than 10mm as it covers a large region with Wales and north west England often staying quite wet if further south is drier which is to be expected. The most recent is August 1995.

For sub regions further south it's more common. Since 1873 in the central england there are 29 months below 10mm, while for south east England also from 1873 there are 42 months below 10mm.

Months in the central England region below 10mm this century:

Feb 2023, March 2011, April 2007, 2011, 2021, May 2020, all seeing under 10mm this century.

 

Some other close ones 21st century for Eng + Wales include:

April 2011: 11.6mm

June 2018: 16.5mm

May 2020: 10.3mm

April 2021: 13.5mm

February 2023: 16.5mm

 

All data here:

https://www.metoffice.gov.uk/hadobs/hadukp/data/download.html

 

Edited February 11 by Metwatch