Summary for November 2006

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

HEADLINE: WARM AND VERY WET AFTER A CHILLY & DRY FIRST-THIRD

(last updated: 01/1200 DECEMBER)

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; )

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TEMPERATURES ETC.

Highest day maximum (date):... 15.1(13)

Highest 24hr maximum (date):.. 15.1(13)

Lowest night minimum (date):...-01.0(03)

Lowest 24hr minimum (date):...-01.0(03)

Lowest overnight grass minimum (date):... –03.4(04)

[ number of days grass minimum < 0degC: ... 09 ]

[ Lowest day maximum (date):... 07.3(21)]

[ Highest night minimum (date):... 12.0(25)]

A. Mean Day (09-18Z) maximum: ... 11.1

A. Mean Night (18-09Z) minimum: ... 05.6

A. Mean of Day Max & Night min: ... 08.3

B. Mean 24hr maximum:... 11.5

B. Mean 24hr minimum:... 04.8

B. Mean of 24hr max & min:... 08.1 [+1.2 anomaly wrt eLTA of 6.9degC]

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

Nr of days minimum at 09UTC <0.0degC:03[dates: 02-04]

Nr of days maximum at 09UTC >=21degC:00

Nr of days maximum at 09UTC >=25degC:00

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

(Notes relating to temperature & allied observations:

This month, the 24hr means and day/night means show significant differences – see above; in particular, there were 9 occasions where the 24hr maximum occurred overnight.

Using the 24hr maximum of 11.5degC, this month by such a measure was the second warmest November in a composite series starting in 1971. However, the mean minimum was nothing like as anomalously high (+1.9max/+0.4min), & overall there have been 10 Novembers equal to or warmer than this one in the past 36 years.)

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PRECIPITATION (PPN/mm)

Total rainfall/melted snow etc:... 129.1 [196% of eLTA of 66mm]

Highest 24hr total:............... 31.7(17)

No. days PPN total >= 0.2:16

No. days PPN total >= 1.0:13

No. days PPN total >=10.0:07

No. days PPN total >=25.0:01

(Notes relating to precipitation & allied observations:

7th: heavy overnight dew / ocnl thick fog produced 0.1mm in gauge at 09Z;

8th: id(very light) between 14 & 15Z, with ir(slight) short-time ~1505Z; ir(mainly slight) between 21 & 23Z;

10th/11th: r(slight) 10/1920Z, then r from ~20Z, to ~11/03Z: ir(slight) thereafter to ~11/05Z;

12th: pr(very few drops)~1525Z;

12th/13th: idr(slight) overnight, with pr between 0815 & 0845Z, when the bulk of the measured rainfall was captured, with PPN csd by 0915Z;

14th: ir 0525/0530Z. dr(slight, ocnl moderate)/ocnl r, from midday to late afternoon;

16th: periods r/R from ~00Z, becoming mainly r(slight) ocnl r from 06Z – 1030Z, then ir(mainly slight) until ~1330Z;

17th: ir (early hours); pr/ir from ~0835Z, continuing through the afternoon (after a dry period late morning), with frequent, short-periods (~10mins at a time) of heavy rainfall between 13 & 17Z, down to slight rain by 1740Z, csd by 1930Z;

19th/20th: r(slight) began ~19/2145Z, soon becoming a wet/windy night with periods r(R), easing to ir(slight) by 20/0530Z: pr(slight, isol moderate) thereafter, until 20/1600Z; further ir/pr(mainly slight) first-half of evening 20th;

21st: pr(slight)~14Z;

22nd: r(slight), ocnl r between 1250 & 1430Z, then ir(slight), but very short period dr/r ~1745Z;

22nd/23rd: lengthy spells r(R) overnight (from ~22Z) – ceased by 0430Z, but further short-period r/R (squally wind) ~0615/0630Z;

23rd: pr(slight)~1740-1750Z;

24th: pr(slight)~0840/0845Z: ir(slight/ocnl moderate) AM, ir(slight) ->continuous slight, ocnl moderate PM, csd by 17Z;

24th/25th: extended periods r(R) overnight (from late evening 24th), easing to intermittent slight by 0500Z;

25th: further ir(slight)/pr(slight) until 1045Z, then r/R (tl/slight 1108-1120Z) becoming r(slight), ocnl r by 1125Z, ceasing by 1140Z. Further r(slight)/r 1245-1315Z & ~14Z;

26th: r(slight) 0625Z soon r(several bursts R), csd by 0740Z. Periods r/R again 0840Z onwards, with tl(slight) from 0935-1138 (see below for thunder details), becoming 1145Z slight, ocnl moderate. Around 1335Z pr(slight), csd by 1505Z, then light pr early evening;

26th/27th: r(slight), ocnl r overnight & morning, ceased by 11Z;

28th: r/R ~02Z to 08Z, then ir(slight) to ~ 10Z; pr(slight) 1615-1620Z;

29th: pr(slight) ~ 13Z

29th/30th: heavy overnight dew, already in evidence at 18Z, produced 0.1mm in gauge at 30/09Z;

1st(DEC): r(slight), ocnl r, from ~0330Z until ~08Z, then idr(slight).

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OTHER TOTALS

Number of days thunder heard: (dates).. 02 (25,26)

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

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Additional comments on the weather in November, 2006

6th/7th: extended periods of fog from late evening 6th, ocnl thick (<200m) until ~07/05Z

13th: sharp but temporary increase in (W/WSW) wind midday/early afternoon to F5 or F6, before easing to F3-4 by 1500Z

[thunder]

25th: tl(slight/3 discharges in total) 1108-1120Z. Accompanied by moderate or heavy ('torrential') rain. Although a small number of discharges, they were all 'sharp' cracks (i.e. close-by), with at least one marked CG discharge.

26th: tl(slight)/odd discharge now and then 0935-1115Z, accompanied by moderate, ocnl heavy rain. Further activity from 1130Z, with a vivid single discharge (CG) very close 1138Z (knocked-out local cable network**) – nothing after that time (though moderate/heavy rain continued for a while).

[ ** on ringing NTL, found that lightning activity had caused widespread problems within the 'RG' postal area east of Reading; also had a report of a strike on a house about 300 m away. ]

[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 02.0 11.5 -00.4 - 04.0 08.6 - - -

02 -00.6 05.3 -02.8 - 00.9 07.6 - -

03 -01.0 03.5 -03.3 - 00.4 08.7 - -

04 -00.9 04.3 -03.4 - 00.7 08.9 tr(x) tr AB

05 03.0 06.1 –00.3 tr(w/x) 04.7 11.6 - tr C

06 02.2 07.9 -00.8 tr(w) 02.8 10.6 - 00.1 D

07 02.1 06.9 -00.8 00.1(wf)06.9 10.0 - - E

08 05.5 09.4 02.0 - 09.3 14.1 tr 00.1

09 05.1 12.7 01.6 00.1 05.3 09.9 - -

10 00.4 05.9 -01.7 - 05.9 10.9 - 05.0 F

11 08.7 12.6 06.4 05.0 09.1 10.6 - - GH

12 06.1 10.6 03.5 - 07.0 11.7 tr 00.6 HI

13 10.0 13.7 07.8 00.6 11.9 15.1 tr 00.1 J

14 10.5 11.9 07.9 00.1 10.9 13.7 01.9 01.9 K

15 11.6 13.1 09.3 - 12.5 14.1 - 13.1

16 10.1 14.3 09.7 13.1 08.1 10.2 03.5 03.9 LM

17 05.8 10.5 03.6 00.4 07.4 11.4 31.4 31.7 N

18 03.2 07.4 01.1 00.3 04.1 08.6 - -

19 00.2 04.4 -01.9 - 03.1 09.5 - 11.6 O

20 08.2 11.6 04.7 11.6 07.9 11.8 00.9 01.1 PQ

21 05.0 08.5 03.1 00.2 04.2 07.3 tr tr

22 03.1 05.7 00.0 - 05.1 10.9 01.0 11.3 RS

23 09.4 12.6 07.6 10.3 09.4 12.1 00.1 00.4

24 06.2 09.8 02.3 00.3 09.4 12.7 02.0 08.1 T

25 12.0 14.2 10.9 06.1 08.3 12.9 06.5 12.7 UV

26 06.4 10.3 03.8 06.2 08.5 11.4 12.1 12.8 W

27 10.5 11.9 08.5 00.7 11.5 13.4 01.1 12.5 X

28 10.9 12.2 09.0 11.4 08.5 11.6 00.2 00.2

29 04.9 08.7 02.1 tr(w) 06.2 12.6 tr 00.1 Y

30 08.4 10.4 05.7 00.1(w) 08.7 10.0 - 01.8

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. tr at 18Z, from melted hoar & earlier dew from previous night

B. day min.(0.7), also 24hr min 5th, occurred 04/09Z

C. tr at 09Z, from melted hoar earlier in night

D. tr at 09Z, from dew deposit overnight

E. overnight dew/ocnl thick fog produced 0.1mm

F. day min.(5.9), also 24hr min 11th, occurred 10/09Z

G. night max.(12.6), also 24hr max 10th, occurred evening 10th

H. day/24hr max.(10.6) 11th & night max 12th occurred at 11/18Z

I. day min.(7.0), also 24hr min 13th, occurred at 12/09Z

J. night max.(13.7), also 24hr max 12th, occurred overnight

K. day min.(10.9), also 24hr min 15th, occurred 14/09Z

L. night min.(10.1), also 24hr min 16th, occurred on 09Z OB after air mass change (falling from night max. of 14.3)

M. night max.(14.3), also 24hr max 15th, occurred sometime overnight

N. night max.(10.5), also 24hr max 16th, occurred 17/09Z

O. day min.(3.1), also 24hr min 20th, occurred 19/09Z

P. night max.(11.6), also 24hr max 19th, occurred 20/09Z

Q. reported grass min.(4.7) occurred before 19/18Z (thermo. set 15Z)

R. day max.(10.9) occurred at 22/1800Z; temperature rose to the night / 24hr maximum (12.6) during the evening/early hours.

S. day min.(5.1), also 24hr min 23rd, occurred 22/09Z

T. day min.(9.4), also 24hr min 25th, occurred 24/09Z

U. night max.(14.2), also the 24hr max 24th, occurred overnight

V. day max.(12.9) occurred during morning

W. day min.(8.5), also 24hr min 27th, occurred in association with R/tl during second-half of morning 26th (see details above)

X. night max.(11.9), also 24hr max 26th, occurred overnight, probably early hours

Y. day min.(6.2), also 24hr min 30th, occurred 29/09Z

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Number of occasions (24hr periods) THIS YEAR (2006)

maximum temperature >= 21degC (70degF) = 92

minimum temperature >= 16degC (61degF) = 24

Rolling 12 month temperature anomaly: +1.2 (was +1.0 end last month)

Rolling 12 month rainfall: 102% of eLTA (was 93% end last month)

Rolling 24 month rainfall: 90% of eLTA (was 85% end last month)

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Total rainfall for this year (2006) so far: 666.4 mm, representing 105% of the 'average' that we should have by the end of November (634mm).

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[SEASONAL NOTES: AUTUMN]

MnTx MnTn Mn24 HiTx LoTn TotRR

SEPTEMBER: 21.7 13.9 17.8 28.8 07.0 86.2

[+4.0][+3.1][+3.6] [129%]

OCTOBER: 16.5 10.9 13.7 20.2 05.7 101.5

[+2.9][+3.6][+3.2] [135%]

NOVEMBER: 11.5 04.8 08.1 15.1 -1.0 129.1

[+1.9][+0.4][+1.2] [196%]

OVERALL: 16.6 9.9 13.2 316.8

[+2.9][+2.4][+2.7] [152%]

[TEMPERATURE]

In a composite Easthampstead Park / Tawfield record starting 1971, the previous warmest Autumn occurred last year (2005), with an average across the three months September, October & November of 11.7ºC; prior to that, the year 1999, with 11.5ºC was the warmest. This year (2006) we have comprehensively beaten these values, with a(provisional) value of 13.2ºC, representing an anomaly on the 1971-2000 dataset of +2.7degC.

(At present, if December turns out to have an 'average' temperature, then we will also have the warmest year in that 36yr series.)

[RAINFALL]

With a total rainfall of (129.1mm), this November is the wettest any month since November 2003 (153.3mm); there have been four wetter Novembers in a composite series starting 1971.

Nearly a quarter (24.3%) of the monthly total fell in the 5 hours midday to 1700GMT on the 17th, with 31.4mm recorded in the 09-18GMT period.

For the Autumn, there have been three wetter such-named seasons (since 1971): 1974, 1976 & (the wettest, with 404mm) 2000.