Summary for September, 2004

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

HEADLINE: DRY/MILD OVERALL: FINE/VERY WARM FIRST-THIRD, THEN UNSETTLED

(last updated: 29/1600 NOVEMBER)

 

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; ) Readings taken at 0900 and 1800 UTC. Where the NIGHT maximum

or DAY minimum are significantly different from figures hereunder, this will be noted in the accompanying text summary. There are now two mean daily 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 .. as kept formerly) .. 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.

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TEMPERATURES ETC.

Highest day maximum (date):... 27.0(05)

Highest 24hr maximum (date):.. 27.0(05)

 

Lowest night minimum  (date):... 05.1(25)

Lowest 24hr minimum   (date):... 05.1(25)

 

Lowest overnight grass minimum (date):... 03.6(25)

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

 

[ Lowest day maximum  (date):...   14.5(25)]

[ Highest night minimum (date):... 16.7(07)]

 

A. Mean Day (09-18Z) maximum:   ... 19.8

A. Mean Night (18-09Z) minimum: ... 11.7

A. Mean of Day Max & Night min: ... 15.7

 

B. Mean 24hr maximum:... 19.8

B. Mean 24hr minimum:... 11.6

B. Mean of 24hr max & min:... 15.7 [+1.5 anomaly on eLTA of 14.2degC/AMENDED]

 

(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:09

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

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

(Notes relating to temperature & allied observations:

none)

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PRECIPITATION (PPN/mm)

Total rainfall/melted snow etc:... 27.3  [41% of eLTA of 67mm]

Highest 24hr total:............... 08.1(12)

No. days PPN total >= 0.2:11

No. days PPN total >= 1.0:08

No. days PPN total >=10.0:00

No. days PPN total >=25.0:00

(Notes relating to precipitation & allied observations:

10th: r(slight)/r 0630-0830Z, intermittent/slight 09Z ceasing soon after;

11th: pr(slight) 1725-1745Z; r(slight) late evening;

12th: pr(very slight) ~13Z; r(slight) 1925-1950Z;

13th: r(R) from ~03Z to 0645Z, ir(slight) then to ~0745Z; pr(slight) mid-afternoon;

13th/14th: r(R) overnight - ceased well before 05Z;

14th: pr ~ 0855Z; pr(slight) during day, no sig. rainfall;

17th: r(slight), short period r, 0710-0850Z; ir(slight/very) during day;

17th/18th: r(slight), ocnl r evening & overnight . . . csd (as slight drizzle) by 18/0630Z;

18th: ir(slight) 12Z-1515Z, then r(slight), ocnl r to 1615Z;

19th: id(very light) morning after 09Z; id(slight) evening;

20th: idr(slight) ~07Z; further dr(slight) during morning, then r 1115-1125Z, dry thereafter;

22nd: ir(slight) 0945-1000Z, further v.light 'spots' PM;

23rd: idr(slight) ~06Z; pr(slight) 09-13Z;

25th: r(slight)/r 1115-1430Z;

25th/26th: heavy dewfall plus 'wet' fog = 0.1mm;

27th: pr(slight) 0930-10Z; id(slight) early PM;

28th: idr(slight) ~0830Z; ir(slight) 09-10Z;

29th: idr(slight), ocnl r(slight) 06-07Z; r(slight) 0845Z, and off/on through day with r(slight) at 18Z;

30th: r(slight), ocnl r since at least 05Z, ceased by 10Z:

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OTHER TOTALS

Number of days thunder heard: (dates).. 00

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 September, 2004

1. Third dry September in a row.

2. Temperature anomaly heavily biased towards warm nights: +2.4C 24hr Min as against +1.3C 24hr Max.

 

... 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  08.6  18.0  07.5  -       14.2  21.5  -        -        -

02  10.7  19.3  09.6  -       15.7  24.0  -        -   

03  12.2  21.7  10.2  -       18.8  24.9  -        -   

04  12.4  22.2  10.8  -       17.9  25.7  -        -   

05  13.1  24.4  11.2  -       20.2  27.0  -        -   

 

06  13.6  25.5  11.6  -       18.8  24.9  -        -  

07  16.7  22.1  16.5  -       16.9  23.6  -        -   

08  14.0  21.3  13.1  -       16.9  23.0  -        -   

09  13.9  19.9  11.4  -       18.1  24.7  -        04.0

10  13.4  21.8  11.3  04.0    16.0  20.1  tr       tr  

 

11  15.0  18.6  14.0  -       16.8  20.6  00.1     00.4

12  09.8  16.7  08.9  00.3    14.4  18.3  tr       08.1

13  13.3  15.6  12.7  08.1    14.3  18.1  00.5     03.8

14  10.6  15.1  09.5  03.3    13.8  18.2  tr       tr  

15  08.0  15.4  06.6  -       12.8  17.5  -        -   

 

16  05.2  14.7  03.7  -       12.0  17.8  -        00.1    A

17  12.9  15.9  12.0  00.1    15.4  17.9  tr       01.0    B

18  15.2  17.2  14.7  01.0    15.0  18.3  01.7     01.7    C

19  08.9  14.9  07.7  tr(W)   12.9  16.7  tr       tr   W=dew deposit: D

20  13.2  15.3  12.3  tr      14.7  17.9  01.6     01.6

 

21  09.7  14.7  08.4  -       13.1  16.3  -        -      

22  10.8  14.9  09.7  -       14.9  18.4  tr       tr      E F

23  15.9  18.9  14.9  tr      13.9  20.5  tr       tr      G

24  07.2  13.8  04.7  -       10.6  15.1  -        -   

25  05.1  12.4  03.6  -       10.2  14.5  02.3     02.4

 

26  10.0  13.8  08.0  00.1    13.2  19.3  -        -       H

27  12.7  16.3  11.4  -       16.3  19.0  tr       tr  

28  13.5  17.8  13.1  tr      14.1  18.0  tr       00.2

29  12.5  15.9  12.0  00.2    12.9  15.0  01.8     03.7    I

30  13.6  15.1  13.0  01.9    15.1  18.0  00.3     00.3    J

 

Remarks:

A. day min. 16th (12.0) also the 24hr min for period ending 17/09Z

B. night max. 17th (15.9) occurred 17/0900Z

C. night max. 18th (17.2) occurred 18/0900Z

D. day min. 19th (12.9) also the 24hr min for period ending 20/09Z

E. night max. 22nd (14.9) occurred 22/0900Z

F. day min. 22nd (14.9) also the 24hr min for period ending 23/09Z

G. night max. 23rd (18.9), also 24hr max for 22nd, occurred 23/09Z

H. overnight rainfall (0.1mm) combination of heavy dewfall/wet fog

I. day min. 29th (12.9), also the 24hr min for period ending 30/09Z

J. night max. 30th (15.1), also 24hr max for 29th, occurred 30/09Z

 

Number of occasions (24hr periods) THIS YEAR (2004)

maximum temperature >= 21degC (70degF) = 80

minimum temperature >= 16degC (61degF) = 13

 

Note relating to temperature anomaly for 2004 (up to end of September)

 

In the Beaufort Park (Easthampstead Park) record (1971 - 2002), the warmest years were:-

1989 +1.1

1990 +1.1

1999 +1.2

2003 +1.1