Summary for March 2004

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

HEADLINE:RATHER COLD FIRST HALF; LESS COLD BUT SHOWERY THEREAFTER

(last updated: 29/1600 November)

NOTE: BREAK IN DATA FROM 26/0900 TO 28/1800; DATA BETWEEN THOSE TWO EVENTS ESTIMATED WHERE REQUIRED.

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

Altitude 80 m (other location details see signature file appended)

(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.

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

TEMPERATURES ETC.

Highest day maximum (date):... 18.1(31)

Highest 24hr maximum (date):.. 18.1(31)

 

Lowest night minimum  (date):... -05.1(01)

Lowest 24hr minimum   (date):... -05.1(01)

 

Lowest overnight grass minimum (date):... -06.1(01)

[ number of days grass minimum < 0degC: ... 08 ]

 

[ Lowest day maximum  (date):...    05.0(10)]

[ Highest night minimum (date):...  10.5(16)]

 

A. Mean Day (09-18Z) maximum:   ...  10.0

A. Mean Night (18-09Z) minimum: ...  03.5

A. Mean of Day Max & Night min: ...  06.7

 

B. Mean 24hr maximum:...  10.0

B. Mean 24hr minimum:...  03.3

B. Mean of 24hr max & min:... 06.7 (+0.0 on eLTA of 6.7/CORRECTED FIGURE)

 

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

Nr of days minimum at 09UTC <0.0degC:04[dates: 01-03,26]

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:

1st: coldest night of 2004 (so far); 3rd: 24hr min (-0.7), occurred 02/09Z; 4th: 24hr min (3.2), occurred 03/09Z; 7th/8th: night minima, grass/air, early in night > cloudy/Sc by dawn; 19th/20th: night minima, grass/air, early in night > cloudy/damp by early 20th;)

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

PRECIPITATION (PPN/mm)

Total rainfall/melted snow etc:... 047.5 (91 % of eLTA of 52mm)

Highest 24hr total:............... 08.3(11)

No. days PPN total >= 0.2:17

No. days PPN total >= 1.0:11

No. days PPN total >=10.0:00

No. days PPN total >=25.0:00

(Notes relating to precipitation & allied observations:

3rd: rain began circa 2030Z, ocnl moderate thereafter;

5th: deep Cu development early afternoon - shower in vicinity, but none here;

6th: very light rain ~0830Z;

6th/7th: light rain o/n [before 06Z];

7th: pr(slight)>pr>phr 1055-1120Z, with small hail giving slushy covering for about 30 mins: pr>phr>rs(slight sleet element only, but a temporary snow pellet phase giving a patchy covering)>r(slight) 1137-1245Z;

10th: v.light s/few flakes/0650-0720Z & again 1425; slight sleet & snow grains from circa 1750Z;

11th: sleet>snow>rain, all very light, 0805-0820Z; further rain/sleet ~1325Z; snow, mainly slight but temporarily moderate 2035-2300Z (only fully covering grass, very patchy otherwise;

12th: further snow early hrs, ocnl moderate (full cover most surfaces but only significant over grass, csd by about 0530Z; r(slight)>r from about 15Z, > r/d(slight) by ~17Z;

12th/13th: r(slight) ocnl r evening & overnight, csd by 13/07Z;

13th/14th: r(slight)/r [plus gusty winds] late eve & overnight;

14th: slight dr AM>~12Z r(slight)/r, csd by 1630Z; ir(slight) eve;

15th: slight r 15-16Z, otherwise drizzle much of afternoon;

18th: slight dr from ~15Z, then short, sharp squall/r(R) 1750Z;

19th: slight, ocnl moderate r from 06Z to early afternoon;

20th: ocnl dr(slight, tempo moderate) early hours to 0730Z; further ocnl r (mainly light) to early PM, then pr(slight) to 17Z;

21st: light pr 06-0815Z; squally pr(mostly light) during day, but ph(slight)rq ~1305Z;

22nd: pr(slight), tempo pr, during day, mainly 11Z-16Z;

23rd: r(slight), ocnl r 0655-0720Z; slight ph/H (diameter up to 6mm) 1155Z; slight psh/H (diameter up to 7mm, with a few snow pellets & isolated flakes of snow) 1400Z; otherwise several, mainly light, rain showers during day & early evening;

24th: ir(slight) overnight, csd by 08Z; ph(slight)r ~14Z; pHr 1620-1632Z, then pr/r(slight) to ~1710Z;

25th: showers during 09-18Z period, with ph(small/light) 0915/20Z & 1407Z;   26th: v.light pr ~0810Z; (estimated) r/d from roughly mid-evening;

27th: (estimated) rain/drizzle much of day;

28th: (estimated) v.light drizzle at time until late afternoon;

31st/1st April: ocnl light rain 01/05Z - 06Z;)

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

OTHER TOTALS

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

Number of days hail < 0.5cm diameter:.. 05

Number of days hail >=0.5cm diameter:.. 02

Number of days snow/rain & snow:....... 05

Number of days snow lying at 09UTC:.... 01

Deepest snow cover (date,s):........... 03(12)

Number of days fog (visibility < 1km @ 09UTC).. 01

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

Additional comments on the weather in March, 2004

5th: wet fog from at least 04Z .. measured 'trace' at 09Z, cleared above 1km by about 0950Z; 12th: note difference between 3cm snow-depth & 8.3mm rainfall reported indicating high water content & large 'pre-melt' of much snow evening 11th; 12th: all sig. snow gone by 13Z; 16th: overnight St broke/dispersed by 10Z, glorious day of variable Ci thereafter; 19th: wind strong from just before dawn to mid-afternoon, mainly F5/6, but 6(7) for a time late AM to early PM; 22nd: dramatic display of mammatus associated with Cb around midday; 23rd: heavy hail/rain showers in VCNTY, but only scrappy/light affairs here - plenty of Cb cap/cal & detached anvils about; 24th: during second hail event (1620-1632Z), grass/conservatory covered, and other surfaces almost so [road became quite icy], with hail diameters 5-7mm, isol 8mm: notably conical (hurt when hitting my head!) - drift of hail in one corner over 3cm deep.

 

... 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 -05.1  03.2 -06.1  -      -01.5  05.1  -        -        -

02 -04.2  03.6 -05.8  -      -00.7  06.6  -        -        A

03  00.2  04.8 -02.9  -       03.2  09.3  -        03.6     B

04  05.7  07.7  04.7  03.6    07.5  09.5  tr       tr  

05  04.0  08.9  02.2  tr(f)   04.8  09.8  -        tr  

 

06  03.8  08.0  01.7  tr      05.5  09.6  -        00.1

07  03.5  07.2  01.5  00.1    03.3  07.5  02.4     02.4

08  00.7  04.8 -02.0  -       04.4  08.5  -        -   

09  02.6  07.3  01.1  -       04.3  07.0  -        tr  

10  00.3  05.0 -01.8  tr      02.1  05.0  tr       tr  

 

11  01.3  02.9  01.0  tr      02.4  05.5  tr       08.3

12  00.5  03.3  00.1  08.3    02.0  05.6  03.2     05.4

13  03.9  06.7  03.4  02.2    06.7  11.1  tr       02.7     C

14  06.9  09.2  06.1  02.7    09.2  10.2  02.2     02.2     D

15  07.9  10.4  06.9  tr      10.1  12.7  00.1     00.1     EF

 

16  10.5  12.1  10.4  tr      11.8  16.3  -        -  

17  07.2  13.2  05.9  -       10.5  14.4  -        tr  

18  07.1  11.7  05.1  tr      08.9  12.7  00.9     04.0

19  06.8  09.1  06.1  03.1    09.1  11.7  04.3     05.0     G

20  07.1  11.8  06.2  00.7    11.4  13.4  00.3     00.3     H

 

21  06.0  13.2  04.9  tr      07.3  11.4  01.5     01.5

22  03.2  08.6  01.2  -       05.8  09.4  01.1     02.2

23  01.8  06.4  00.6  01.1    04.8  08.3  00.3     00.8

24  02.9  06.3  01.3  00.5    04.3  08.3  06.8     06.8

25  00.1  04.7 -01.7  tr      03.7  08.2  00.8     00.8

 

26 -00.2  06.4 -02.2  tr      04.4 (08.7) -       (00.8)   I

27 (06--) ----  ---- (00.8)   ---- (08.6)(tr)     (00.3)   I

28 (06--) ----  ---- (00.3)   ----  09.3 (tr)     (tr)     I

29  05.8  08.6  03.3  -       07.4  12.9  -        -   

30  02.6  11.1 -00.2  -       07.3  14.8  -        -   

 

31  04.7  11.8  03.7  -       10.4  18.1  -        00.2

 

Remarks:

A. day minimum (-0.7), also 24hr min for 3rd, occurred 02/09Z

B. day minimum (3.2), also 24hr min for 4th, occurred 03/09Z

C. night maximum (6.7), also 24hr max for 12th, occurred 13/09Z

D. night maximum (9.2) occurred 14/09Z

E. night maximum (10.4), also 24hr max 14th, occurred end night 14/15th

F. day minimum (10.1), also 24hr min 16th, occurred 15/09Z

G. night maximum (9.1) occurred 19/09Z

H. night maximum (11.8), also 24hr max for 19th, occurred late night

I. various estimated or missing data - see head of form; minima to nearest

   whole degree only.

 

Mean temperature (24hr) 1st to 15th March inclusive:- 5.1degC, which is 1.6C below the *all* March mean.