**** SEE IMPORTANT NOTE AT BOTTOM OF THIS SHEET ****

Summary for May 2007

====================

HEADLINE: WARM/DRY START, THEN WET FROM 7TH: VERY WET/COLD SPRING HOLIDAY

(last updated: 01/0900 JUNE)

**** SEE IMPORTANT NOTE AT BOTTOM OF THIS SHEET ****

Location: Tawfield/Wooden Hill area of SW Bracknell, Berkshire, UK

Altitude 80 m (other location details see elsewhere on web site.)

(temperatures [standard screen] degC; rainfall/melted snowfall mm; snow depths cm; )

=================================

TEMPERATURES ETC.

Highest day maximum (date):... 25.1(24)

Highest 24hr maximum (date):.. 25.1(24)

Lowest night minimum (date):... 03.6(29)

Lowest 24hr minimum (date):... 03.6(29)

Lowest overnight grass minimum (date):... 02.7(29)

[ number of days grass minimum < 0degC: ... 00 ]

[ Lowest day maximum (date):... 08.0(28)]

[ Highest night minimum (date):... 13.6(07)]

A. Mean Day (09-18Z) maximum: ... 17.3

A. Mean Night (18-09Z) minimum: ... 09.2

A. Mean of Day Max & Night min: ... 13.3

B. Mean 24hr maximum:... 17.5

B. Mean 24hr minimum:... 09.2

B. Mean of 24hr max & min:... 13.3 [+0.9 anomaly wrt eLTA of 12.4degC]

(data below relate to 24 hr day beginning 09Z on date given)

Nr of days minimum at 09UTC <0.0degC:00

Nr of days maximum at 09UTC >=21degC:05

Nr of days maximum at 09UTC >=25degC:02

Nr of days maximum at 09UTC >=30degC:00

(Notes relating to temperature & allied observations:

none)

=================================

PRECIPITATION (PPN/mm)

Total rainfall/melted snow etc:...127.9 [221% of eLTA of 58 mm]

Highest 24hr total:............... 34.5(27)

No. days PPN total >= 0.2:18

No. days PPN total >= 1.0:13

No. days PPN total >=10.0:04

No. days PPN total >=25.0:01

(Notes relating to precipitation & allied observations:

6th: d(very slight) 1020-1025Z; r(slight/few large drops)~1720Z;

6th/7th: sporadic d/r overnight;

7th: dr(slight) at 09Z, becoming r/R by 1110Z, bec. r(slight)/r by 1230Z, bec. r(slight) by 1250Z, csd 1310Z [ sharp frontal clearance ];

8th: id(very light) AM;

9th: sporadic r(slight), ocnl r, from early hours, then ocnl dr(slight), tempo dr(m) PM;

9th/10th: periods r(slight), ocnl r, overnight;

10th: ir(slight) from 1037Z, with r(R) mid/late afternoon;

10th/11th: further periods r/R overnight, ceased by 05Z;

11th: pr/r(mainly slight) off and on through day;

11th/12th: periods r/R overnight, mainly between 22Z & 02Z;

12th: pr(mainly slight) through day, but pr/R for a while between 12 & 13Z;

12th/13th: sporadic r(slight) overnight;

13th: r(slight) began 0830Z, bec. r by 0855Z, then r(slight), ocnl r until 1430Z, with period r/R 1150-1220Z, & tl (single discharge) 1143Z; pr early evening;

13th/14th: ocnl r(mainly slight) overnight, then dr(moderate ocnl heavy) from 14/0845Z, bec. ir(slight) by 0930Z & mainly dry PM;

15th: r(slight)[isol r] from 0745Z bec. mainly idr(mainly slight) by 0930Z, csd completely by 1015Z: pr(mainly slight) thereafter, but pr between 1740 & 1755Z, pr(slight) ceased by 19Z;

16th: r(slight), sporadic with very short period r, early/mid-afternoon;

16th/17th: periods of light/moderate rain overnight, then dr(slight/moderate) end of night;

17th: ir/d(slight) 09Z - ~14Z;

18th: id(slight) 0630-07Z; r(slight) began ~17Z, idr(m), csd 1750Z; further dr(mainly slight) 18Z then pr(slight) until ~20Z;

21st: ir(slight) between 06 & 08Z: further r(slight) from 0920Z, with period r AM, then off and on throughout the afternoon & early evening, always slight;

26th: sporadic r(slight), isol r, since ~01Z, lingering through morning, mainly dry afternoon;

26th/27th: sporadic, mainly light rain overnight;

27th: r(slight)/r from ~05Z until ~1215Z (short-period R late morning). Then ir(slight) until ~1630Z, when turned continuous slight again, bec. r ~1755Z --à

27th/28th: r/R (lengthy spells of the latter) overnight, still r by 28/09Z;

28th: further r(slight), ocnl r from 09Z, more or less continuous to at least 18Z, then ir(slight, isol early-evening moderate), finally dying out late evening;

30th: ir(slight) from ~05Z, with period near-continuous 0630-0830Z: further dr(slight/moderate) until ~1430Z, continuous from midday to ~1400Z;

30th/31st: ir(slight) overnight, mainly second-half;

31st: pr(slight) from ~08Z to late-morning;

31st/1st June: pr(slight) overnight;

)

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OTHER TOTALS

Number of days thunder heard: (dates).. 01 (13)

Number of days hail < 0.5cm diameter:.. 00

Number of days hail >=0.5cm diameter:.. 00

Number of days snow/rain & snow:....... 00

Number of days snow lying at 09UTC:.... 00

Deepest snow cover (date,s):........... -

Number of days fog (visibility < 1km @ 09UTC).. 00

=================================

Additional comments on the weather in May, 2007

7th: sharp, but very brief squall ~14Z, wind temporarily F6 or F7.

[thunder]

13th: period r/R 1150-1220Z, & tl (single discharge) 1143Z

[snow]

Nil

... these data can also be viewed at:-

http://homepage.ntlworld.com/booty.weather/metinfo/wxdata/climintro.htm

Tn Tx Tg RR Tn Tx RR RR24hr Remark code (below)

(09Z) (09Z) (09Z)(18-09Z) (18Z) (18Z) (09-18Z) (from 09Z today)

01 08.7 16.6 05.9 - 15.3 20.9 - - -

02 08.5 18.6 06.2 - 15.2 21.5 - -

03 07.0 18.9 05.6 - 10.2 15.4 - -

04 08.2 13.1 07.6 - 09.7 16.6 - -

05 08.7 13.7 08.7 - 10.1 15.6 - -

06 08.2 14.7 04.4 - 14.4 19.7 tr tr

07 13.6 16.6 13.0 tr 14.3 17.5 24.6 24.6

08 09.7 15.6 08.5 - 12.2 18.7 tr 00.5 A

09 10.0 (12.7) 09.6 00.5 12.4 14.1 01.1 02.7 A

10 09.6 13.8 08.3 01.6 11.1 15.7 05.1 10.2

11 08.0 12.5 06.9 05.1 12.0 16.0 00.4 04.1

12 09.6 15.1 08.4 03.7 12.4 15.5 06.1 06.5

13 09.9 14.7 08.5 00.4 11.9 14.8 08.4 12.7

14 10.2 14.2 09.3 04.3 09.8 12.2 01.7 02.3

15 06.0 11.6 04.5 00.6 11.3 15.9 03.2 03.5

16 08.7 14.2 07.6 00.3 12.7 16.4 tr 04.6

17 12.5 15.9 x 04.6 15.9 19.6 tr tr B

18 12.6 18.7 09.8 tr 14.0 20.0 00.2 00.4

19 08.4 14.8 06.9 00.2 14.0 17.0 - -

20 05.1 15.6 03.5 - 15.6 19.6 - tr

21 11.4 17.5 09.9 tr 12.6 13.6 00.9 00.9

22 10.0 16.5 08.0 tr 16.5 22.4 - - C

23 09.8 20.5 08.1 - 19.8 25.0 - -

24 13.3 22.8 11.7 - 22.1 25.1 - -

25 13.2 23.7 11.5 - 17.5 22.0 - 00.8

26 09.9 17.5 09.9 00.8 10.5 13.9 tr 07.2

27 09.4 12.4 09.6 07.2 10.3 11.4 04.1 34.5 D

28 05.7 10.3 05.5 30.4 06.0 08.0 05.6 06.6

29 03.6 11.6 02.7 01.0 11.6 16.8 - 00.3 E

30 05.9 14.0 04.3 00.3 11.2 17.4 05.4 05.5

31 09.3 15.5 07.5 00.1 15.5 19.3 tr tr

Readings taken at 0900 and 1800 UTC. Where the NIGHT maximum or DAY minimum are significantly different from 24hr values, this will be noted in the listing against a 'Remarks' letter. There are two mean temperatures shown: the first is the mean of the average day maximum and average night minimum (A), and the second is the average of the 24hr maximum and 24hr minimum (B) .. the anomalies are shown for this latter figure from 1971-2000 estimated Long Term Averages. Rainfall is credited to the 24hr day beginning 0900 UTC.

Remarks:

A. evening reading 8th taken 2000Z: overnight maximum occurred at 08/20Z, all other data represent 'true' 09-18, or 18-09 periods.

B. grass min. thermo. not put out (forgot!)

C. night max.(16.5), also 24hr max. 21st, occurred 22/09Z

D. grass min.(9.6) higher than overnight min.(9.4): no obvious error

E. night max.(11.6), also 24hr max. 28th, occurred 29/09Z

Number of occasions (24hr periods) THIS YEAR (2007)

maximum temperature >= 21degC (70degF) = 10

minimum temperature >= 16degC (61degF) = 00

Rolling 12 month temperature anomaly: +2.2 (was +2.2 end last month)

With 127.9 mm of rainfall, this May is the second-wettest such-named month in the local composite record that began in 1971; if it were not for the exceptional fall of rain that occurred in May 2000 (7th), this would have been THE wettest May in that series.

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Spring summary:

meanTn(anom) meanTx(anom) mean24h(anom) totRain(anom)

Mar: 03.6 (+0.2) 11.4 (+1.5) 07.5 (+0.8) 49.0 (94%)

Apr: 06.8 (+2.1) 18.0 (+5.1) 12.4 (+3.6) 1.9 (4%)

May: 09.2 (+1.7) 17.5 (+0.2) 13.3 (+0.9) 127.9 (221%)

Seas: 06.5 (+1.3) 15.6 (+2.2) 11.1 (+1.8) 178.8 (110%)

*****

THIS WILL BE THE LAST FULL MONTH OF OBSERVATIONS FROM THIS SITE: MY WIFE AND I ARE MOVING TO DORSET, AND THIS TASK SHOULD BE COMPLETED SOMETIME DURING THE SECOND-HALF OF JUNE 2007. I WILL CONTINUE TO UPDATE DAILY OBSERVATIONS UNTIL A FEW DAYS BEFORE WE ARE DUE TO GO.

I HOPE YOU HAVE FOUND THESE DATA OF INTEREST; I HOPE TO RE-START ROUTINE OBSERVING IN DORSET IN DUE COURSE.

MARTIN ROWLEY

*****