Monthly Report for December 2009

Weather Summary
Measure	Mean / Sum (anomaly)	Min	Max	Mean Time
Minimum Temperature	1.6 °C (-2.0)	-3.9 °C	9.3 °C	13:05
Maximum Temperature	5.9 °C (-2.3)	0.6 °C	12.3 °C	14:20
Mean Temperature	3.8 °C (-2.2)	-1.7 °C	10.6 °C
Minimum Humidity	84%	66%	98%	12:20
Maximum Humidity	97%	90%	98%	10:15
Mean Humidity	92%	81%	98%
Minimum Pressure	1002 hPa	983 hPa	1032 hPa	14:17
Maximum Pressure	1009 hPa	989 hPa	1034 hPa	10:45
Mean Pressure	1005 hPa	986 hPa	1033 hPa
Mean Wind Speed	4.7 mph (-0.4)	1.5 mph	9.0 mph
Maximum Wind Speed	11.1 mph	4.3 mph	22.8 mph
Maximum Gust	16.8 mph	6.2 mph	33.1 mph	10:26
Mean Wind Direction	157° [SSE]	n/a	270° [W]
Rainfall	76.5 mm (134%)	0.0 mm	11.5 mm
Maximum Hourly Rain	1.6 mm	0.1 mm	4.4 mm	11:58
Maximum 10-min Rain	0.6 mm	0.3 mm	1.6 mm	12:06
Maximum Rain Rate	3.2 mm/h	0.6 mm/h	8 mm/h	13:26
Minimum Dew Point	0.2 °C	-6.1 °C	8.9 °C	12:50
Maximum Dew Point	5.0 °C	-0.8 °C	11.3 °C	12:47
Mean Dew Point	2.5 °C	-3.8 °C	10.2 °C
Night Minimum (21-09)	2.3 °C	-3.9 °C	9.4 °C
Day Maximum (09-21)	5.7 °C	0.6 °C	11.6 °C
Max 10m Temp Rise	0.4 °C	0.1 °C	1.3 °C	10:56
Max 1hr Temp Rise	1.0 °C	0.3 °C	2.2 °C	12:19
Max 1hr Hum Rise	4%	0%	12%	12:53
Max 10m Temp Fall	0.4 °C	0.1 °C	1.3 °C	12:32
Max 1hr Temp Fall	1.0 °C	0.3 °C	2.1 °C	14:37
Max 1hr Hum Fall	5%	0%	22%	11:31
Max 10m Wind Speed	8.1 mph	3.4 mph	16.0 mph	11:04
Minimum Feels-like	-1.7 °C	-9.7 °C	7.6 °C	11:20
Maximum Feels-like	6.0 °C	0.6 °C	14.0 °C	14:04
Mean Feels-like	2.3 °C	-4.4 °C	11.9 °C	n/a
Air-frost Hrs	95 hrs	0 hrs	20 hrs
Minimum PM2.5	0.0 µg/m³	0.0 µg/m³	0.0 µg/m³
Maximum PM2.5	n/a	n/a	n/a
Mean PM2.5	n/a	n/a	n/a
Temperature Range	4.2 °C (-0.4)	1.5 °C	7.7 °C
Humidity Range	13%	0%	30%
Pressure Range	8 hPa	2 hPa	15 hPa
Sun Hours	75 (115%) [34%]
Wet Hours	96 (155%) [13%]

NB: Hover over a value to see how many days of data it is from. Sun hrs, Wet hrs, Cloud cover and Events are based on manual observation and provided for interest only.

Written report

December 2009

December 2009: 2nd-coldest December of 17 since 2009, and sunny too, with lying snow

Mean 3.8°C, 2.1°C below normal, the 2nd-coldest December of 17 since 2009. Average max 5.9°C and lows 1.6°C. Warmest 12.3°C (06 Dec), coldest night −3.9°C (23 Dec). 9 air frosts.
Rain 76.5 mm, 134% of normal, over 17 days of 1 mm+. The biggest fall was 11.5 mm on 29 Dec.
Sunshine 74.6 hours, 115% of normal, 3rd-sunniest of 17 station Decembers.
Date records still standing: 02 Dec (10.9 mm rain), 06 Dec (7.1 mm rain), 19 Dec (6.5 h sun), 20 Dec (7.0 h sun).
Snow fell on at least 5 days, lay on 7 (max depth 6.0 cm), fog was noted at 09 on at least 1 day.

Written Mon 02 Nov, 18:03 GMT

‹ Nov 2009 Jan 2010 ›

Written reports for 2009: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec · the year

Days Of...
Rainfall		Temperature		Sunshine		Other
> 0.0 mm	24	Min < -5.0 °C	0	> 0 hrs	26	Falling Snow	5
> 0.1 mm	22	Min < 0.0 °C	9	> 1 hrs	21	Lying Snow	7
> 0.3 mm	20	Mean < 0.0 °C	5	> 3 hrs	8	Hail	0
> 1.0 mm	17	Mean > 20.0 °C	0	> 5 hrs	3	Thunder	0
> 5.0 mm	7	Max > 25.0 °C	0	> 10 hrs	0	Dense Fog	1
> 10.0 mm	2	Max > 30.0 °C	0	> 25% max poss.	21	Gusts > 30mph	2
> 20.0 mm	0	Ice Days	0	> 95% max poss.	1	Total Events	15

Misc.

Mean rainfall for days with >0.3mm: 3.8 mm
Total snowfall: 16.5 mm

Graphs and Charts

Mean Temperature

Variable

Measure

View more charts for this month

Intraday conditions

Per-minute readings across the month (downsampled for display). Choose a variable below.

Wind rose

Daily breakdown

Day numbers link to the detailed daily report. Wide tables can be scrolled horizontally.

Temperature, rain, sunshine & wind

Day	Tmin	Tmax	Tmean	Rain	Hr max	10m rain	Rate	Sun	Wmean	Wmax	Gust	Wdir	W10m
1	0.4	5.9	3.1	0.3	-	-	-	5	2.8	8.1	11.4	225°	5.6
2	5.4	10.1	7.7	10.9	4.4	1.6	-	2	3.3	6.9	13.4	180°	6.4
3	2.5	7.6	6.2	2.2	1.4	-	-	0	5.9	12.7	19.6	270°	11.2
4	1.6	7.9	4.3	1.6	0.5	-	-	4	4.3	8.1	11.3	225°	6.3
5	7.4	11.6	9.3	5.5	1.9	-	-	3	6.1	10.4	15.0	225°	10.1
6	7.7	12.3	9.8	7.1	4.1	-	-	4	7.8	13.9	25.3	225°	12.9
7	5.7	10.8	8.5	3.0	1.6	0.5	3.0	0	6.1	14.8	22.5	180°	10.5
8	4.4	10.5	7.2	1.1	0.5	0.3	0.7	3	4.7	10.5	17.3	225°	6.7
9	9.3	11.6	10.6	0.5	0.5	0.3	0.6	1	3.5	9.7	12.8	225°	6.2
10	3.6	10.0	7.6	0.5	-	0.3	-	6	4.0	10.5	15.2	270°	8.8
11	2.1	6.5	4.2	0.0	-	-	-	2	3.5	8.7	10.9	0°	6.0
12	3.8	7.4	5.0	0.0	-	-	-	3	4.8	12.5	15.4	45°	8.0
13	2.3	6.2	4.3	0.5	-	-	-	2	5.0	10.9	16.1	0°	8.2
14	0.5	4.7	2.8	0.3	0.3	-	-	3	1.5	4.3	6.2	45°	3.4
15	0.0	3.6	1.5	0.0	-	-	-	2	2.2	6.9	10.7	90°	4.9
16	-2.1	2.6	0.1	3.5	0.8	0.3	1.9	0.3	3.2	8.7	13.0	225°	5.5
17	-0.9	3.4	1.5	2.0	2.0	-	-	2	9.0	22.8	33.1	0°	15.1
18	-2.0	0.6	-0.2	3.0	3.0	-	-	4	7.5	19.9	32.7	0°	16.0
19	-3.5	0.7	-1.7	0.0	-	-	-	6	4.6	12.7	16.8	270°	-
20	-3.3	1.1	-0.4	2.0	-	-	-	7	4.9	10.7	15.2	225°	7.0
21	-2.9	1.6	-0.5	6.0	-	-	-	0	2.0	8.1	10.2	135°	5.4
22	-2.3	1.3	0.0	0.0	-	-	-	3	2.9	9.2	14.8	270°	7.6
23	-3.9	3.8	-0.5	5.7	-	-	-	2	1.5	8.1	13.8	135°	7.2
24	1.7	4.8	3.2	1.1	1.1	0.3	2.0	0.2	2.5	6.4	9.8	135°	5.0
25	1.5	5.2	2.4	0.1	-	-	-	2	4.7	10.9	15.4	270°	7.5
26	5.2	8.3	6.6	1.7	0.8	0.8	8	1	6.4	12.3	25.9	225°	10.1
27	2.6	6.3	4.9	0.0	-	-	-	2	7.4	16.3	25.5	270°	10.1
28	-1.2	4.0	1.5	0.0	-	-	-	5	2.8	7.4	10.5	90°	6.0
29	1.5	3.8	3.0	11.5	3.2	1.1	8	0	7.1	16.3	25.6	90°	10.7
30	2.6	4.1	3.4	6.3	1.1	0.3	1.6	0	5.9	12.3	15.4	45°	8.0
31	0.6	3.4	2.5	0.1	0.1	-	-	0.1	6.7	12.7	19.2	45°	8.0

Humidity, dew point & pressure

Day	Hmin	Hmax	Hmean	Dmin	Dmax	Dmean	Pmin	Pmax	Pmean
1	77	95	87	-0.6	3.2	1.1	1004	1013	1008
2	86	98	95	3.2	9.0	7.0	993	1004	998
3	74	98	89	-0.3	7.3	4.6	992	1002	997
4	74	97	84	-0.4	7.5	1.8	1001	1008	1004
5	82	98	93	6.3	10.8	8.2	996	1001	998
6	66	96	84	3.9	11.3	7.1	990	1004	997
7	81	94	88	3.9	8.4	6.6	995	1004	1000
8	83	98	91	3.0	10.2	5.8	1001	1012	1006
9	95	98	97	8.9	10.9	10.2	1012	1021	1016
10	77	97	89	2.8	9.5	5.9	1021	1033	1027
11	96	98	98	1.8	6.2	3.9	1032	1034	1033
12	81	98	94	2.7	6.3	4.1	1029	1033	1031
13	84	95	91	1.3	4.2	2.9	1025	1029	1027
14	89	98	95	-0.2	4.1	2.0	1019	1025	1022
15	77	96	86	-2.4	3.0	-0.6	1018	1020	1019
16	86	98	94	-3.5	2.3	-0.8	1007	1018	1012
17	72	98	89	-4.2	2.9	-0.1	1006	1010	1008
18	86	97	92	-3.9	-0.4	-1.4	1009	1015	1012
19	77	90	86	-5.3	-0.8	-3.8	1000	1015	1008
20	73	97	84	-6.1	0.2	-2.8	997	1000	998
21	85	98	93	-4.4	1.2	-1.5	984	997	990
22	96	98	98	-2.6	1.0	-0.3	983	990	986
23	98	98	98	-4.2	3.5	-0.8	989	991	990
24	98	98	98	1.4	4.5	2.9	985	989	987
25	93	98	97	1.2	4.9	2.0	988	1003	996
26	86	98	94	4.3	7.1	5.6	998	1002	1000
27	68	95	81	-0.7	4.7	1.9	996	1006	1001
28	80	98	91	-2.5	2.7	0.2	1001	1006	1004
29	94	98	97	1.2	3.5	2.6	991	1001	996
30	98	98	98	2.3	3.8	3.1	990	998	994
31	83	98	92	-1.6	2.5	1.3	997	1001	999

Other measures

Day	Night	Daymax	T+10m	T+1h	H+1h	T-10m	T-1h	H-1h	Fmin	Fmax	Fmean	AF hrs	AQmin	AQmax	AQmean
1	0.4	5.9	0.7	1.9	6	0.3	0.7	8	-1.9	5.9	2.6	0	-	-	-
2	5.4	10.1	0.5	1.3	7	0.7	1.4	10	1.8	10.7	7.4	0	-	-	-
3	7.2	5.7	0.2	0.3	3	0.5	1.1	9	-0.6	7.7	4.7	0	-	-	-
4	1.6	7.9	1.1	2.2	11	0.3	0.8	7	-2.0	8.1	3.2	0	-	-	-
5	7.4	11.6	-	-	-	-	-	-	5.1	13.3	8.9	0	-	-	-
6	9.4	10.2	0.4	0.8	5	0.8	2.0	22	4.9	14.0	9.7	0	-	-	-
7	7.4	10.8	0.2	0.7	5	0.4	1.2	4	2.3	11.2	7.2	0	-	-	-
8	4.4	10.5	0.2	0.9	6	0.1	0.5	4	1.1	11.9	5.9	0	-	-	-
9	9.3	11.6	0.2	0.7	1	0.3	0.8	2	7.6	13.3	11.9	0	-	-	-
10	6.5	9.6	0.4	1.0	4	0.3	1.0	7	2.0	11.1	7.0	0	-	-	-
11	2.1	6.5	0.6	1.2	1	0.3	0.8	1	-0.1	6.5	3.4	0	-	-	-
12	4.1	7.4	0.4	1.0	5	0.3	1.2	8	-0.1	7.4	3.7	0	-	-	-
13	3.6	6.2	0.6	1.4	4	0.5	1.0	6	0.1	6.2	2.6	0	-	-	-
14	0.5	4.7	-	-	-	-	-	-	-0.9	4.7	2.6	0	-	-	-
15	0.7	2.3	0.5	0.8	4	0.3	1.0	7	-2.8	3.6	1.2	0	-	-	-
16	-2.1	2.6	0.5	0.8	4	0.8	1.1	2	-5.2	2.6	-1.2	10	-	-	-
17	1.0	3.4	0.3	1.0	12	0.4	1.2	9	-8.1	3.4	-2.6	2	-	-	-
18	-1.3	0.6	0.2	0.7	5	0.2	0.9	3	-7.8	0.6	-4.4	13	-	-	-
19	-3.5	0.7	-	-	-	-	-	-	-9.7	0.6	-4.0	20	-	-	-
20	-3.3	1.1	0.7	2.1	4	0.5	1.4	6	-8.3	1.1	-3.0	12	-	-	-
21	-2.9	1.6	1.3	1.9	5	1.3	1.2	6	-5.7	1.6	-0.9	13	-	-	-
22	-0.3	1.3	0.3	0.5	1	0.3	0.9	2	-5.1	1.3	-1.0	8	-	-	-
23	-3.9	3.8	0.4	1.5	0	0.8	2.1	0	-3.9	3.8	-1.2	13	-	-	-
24	1.7	4.8	0.2	0.9	0	0.1	0.6	0	-1.6	4.8	2.3	0	-	-	-
25	1.5	5.2	0.4	1.1	2	0.2	0.6	4	-2.5	4.7	0.0	0	-	-	-
26	5.2	8.3	0.2	0.8	4	0.2	1.1	7	1.7	7.5	4.1	0	-	-	-
27	4.2	6.3	0.3	0.8	4	0.3	1.0	7	-1.1	5.1	1.8	0	-	-	-
28	-1.2	4.0	0.4	1.4	4	0.2	1.0	5	-2.4	4.0	0.4	4	-	-	-
29	1.5	3.8	0.2	0.8	2	0.1	0.3	3	-2.9	3.1	-0.2	0	-	-	-
30	3.1	4.1	0.5	0.5	0	0.5	0.5	0	-2.0	4.1	0.9	0	-	-	-
31	2.5	3.4	0.1	0.3	2	0.2	0.7	4	-4.1	3.2	-0.9	0	-	-	-

View daily report for the 1st