My December

Temperature:
The mean temperature for the month was 17.4C was well above my December average of 15.2C and the warmest I've recorded. The coldest December was 2004 with 12.7C.
The warmest day was the 18th with 35.1C, a new December record. The minimum was 6.4C on the 25th. My coldest December temperature to date is 1.3C in 2006.

No December days have ever been recorded with a temperature at or below 0 in the past 11 years. There were no days where the maximum temperature for the day was less than 10C. Twenty nine days reached or exceeded 15C, equaling my December average. There were 22 days that reached or exceeded 20C, my average is 17. There were 11 days that reached or exceeded 25C, my average is 6 and 2 days reached or exceeded 30C, my average is 1. One day exceeded 35C for the first time in my records

Wind: (Records from 2001)
The monthly wind run of 5593km is 91% of my December average of 6141km. The windiest December was 2004 with 6978km, the least windy 2000 with 5377km. The highest gust was 69km/h from the south south west on the 24th. This was also the maximum gust for the year.

Rainfall:
December had 42.0mm of rain over 10 days, 68% my 62mm December average.  The wettest day was the 28th with 27.5mm. My wettest December day was 20th December 2006 with 55.4mm. The wettest December was 2004 with 137.8mm, the driest, 2003 with 2mm on just 1 day.

Barometer: (Records from 2006)
The average pressure for the month was close to my December average of 1011.5 hPa with 1010.5 hPa. Maximum pressure change of 31.6 hPa is well above  my December average of 17.6.

NIWA monthly climate summaries can be seen here.

December 2010 Summary
Temperature
Mean 17.4 C
Mean Maximum 23.3 C
Mean Minimum 12.4 C
Maximum High 35.1 C (18th)
Maximum Low 19.7 C (21st)
Minimum High 12.8 C (8th)
Minimum Low 6.4 C (25th)
Wind Speed and Direction
Maximum Gust 69 km/h (24th)
Mean 7.9 km/h
Wind Run 5593 km
Max Daily Windrun 282 km (21st)
Prevailing Direction East Nth East
Barometer
Maximum 1027.3 hPa (1st)
Minimum 981.2 hPa (28th)
Mean 1010.5 hPa
Max Daily Change +31.6 hPa (28th)
Rainfall
Days with Measured Rainfall
(Greater than 0.2mm)
10
Max Daily Rainfall 27.5 mm (28th)
Monthly Rainfall 42.0 mm
Humidity
Maximum
97 % (17th)
Minimum 24 % (18th)

December Daily Observations
Temperature Wind Rainfall Barometer
Date Min Max Mean Mean
(Km/h)
Gust
(Km/h)
Run (km) Prevailing Dir 10 Minute Max (mm) Total (mm) Min (hPa) Max (hPa) Change (hPa)
1 12.6 18.8 14.8 8.2 32 188 East Nth East 0 0 1024.4 1027.3 +3.2
Morning drizzle clearing but remaining mostly cloudy with NE winds.
2 13.5 17.4 15.0 5.6 24 128 East Nth East 0 0 1022.2 1025.2 -3.0
Overcast with NE winds
3 11.9 22.3 16.8 3.5 21 79 East Nth East 0 0 1018.0 1023.6 -5.6
Some cloud but mostly sunny with light NE winds.
4 12.8 19.7 16.5 10.6 43 242 East Nth East 0 0 1010.8 1021.6 -10.8
Some morning cloud but sunny with a fresh NE wind.
5 9.8 27.1 18.9 4.7 26 108 East Nth East 0 0 1006.8 1010.6 -3.8
Overcast with thin high cloud for most of the day. Light southerly winds turning NE later in the afternoon.
6 11.3 26.9 16.7 7.6 44 175 South Sth West 0.5 0.5 1004.9 1014.8 +9.9
Sunny and warm with light southerly winds in the morning. Cloud increasing and winds strengthening in the afternoon with evening showers and drizzle.
7 9.6 14.5 11.5 6.9 34 158 South Sth West 0.5 3.0 1014.8 1021.0 +6.2
Morning light rain and drizzle clearing but remaining overcasty and cool with southerly winds.
8 8.7 12.8 10.4 10.2 43 234 South Sth West 0.5 0.5 1020.7 1024.0 +3.3
Overcast with morning drizzle and cool southerly winds
9 7.5 20.2 12.2 4.8 24 106 South Sth West 0 0 1015.5 1023.5 -8.0
Morning cloud breaking to a sunny afternoon. Southerly winds turning NE from mid afternoon.
10 8.3 18.0 13.6 6.9 35 158 East Nth East 0.5 0.5 993.1 1015.8 -22.7
Cloud increading with light showers in the evening.
11 14.1 29.8 20.3 5.2 40 120 East Nth East 0 0 989.8 1009.6 +19.8
Sunny and very warm in the morning with light breezes. A cooler NE winds in the afternoon.
12 10.8 20.3 16.2 10.9 44 250 East Nth East 0 0 1009.8 1015.7 +5.9
Thin high cloud in the morning, thickening in the afternoon with fresh to stron NE winds.
13 15.1 28.6 21.5 9.5 34 217 East Nth East 0.5 1.0 1007.7 1012.6 -4.9
Variable cloud, NE wind turning warm NW early afternoon then southerly in the evening.
14 13.8 22.2 16.8 10.2 29 232 East Nth East 0 0 1010.0 1018.9 +8.9
Southerly winds turning NE from mid afternoon. cloud breaking from midday.
15 14.1 19.2 15.9 4.3 27 99 East Nth East 0.5 0.5 1018.9 1023.0 +4.1
Mostly cloudy but cloud breaking late afternoon for a time. Afternoon shower, light NE winds.
16 13.3 18.5 15.7 7.8 30 179 East Nth East 0.5 0.5 1014.1 1020.7 -6.6
Cloudy, evening showers, NE winds
17 15.0 20.3 16.4 9.5 34 220 East Nth East 0.5 7.5 1000.2 1013.9 -13.7
Overcast with light rain clearing mid afternoon with cloud breaking a little near evening.
18 16.3 35.1 24.4 7.0 31 159 East Nth East 0 0 1000.0 1007.3 +7.3
Morning cloud clearing to a very warm afternoon with light winds tending NW then turning NE later in the afternoon. Highest December temperature I've recorded to date. Previous record was 33.5C in 2007.
19 15.1 22.6 18.0 9.3 33 214 East Nth East 0.5 0.5 997.0 1007.9 -10.9
Overcast for most of the day with showers from late morrning. Cloud breaking later in the afternoon with sunny intervals. NE winds.
20 17.8 29.8 23.2 6.8 30 156 North Nth East 0 0 1000.2 1005.2 +5.0
Warm north to NW winds, cloud breaking in the afternoon.
21 19.7 32.6 24.4 12.3 55 282 North Nth WEst 0 0 989.6 1006.2 +16.6
Variable cloud with strong gusty nor'west winds in the afternoon.
22 12.2 29.0 22.1 11.2 61 256 North Nth West 0 0 1000.3 1011.0 +10.7
Sunny and very warm with strong north to NW winds, easing in the evening.
23 8.9 26.3 17.3 6.5 39 149 East Nth East 0 0 1006.5 1017.7 -11.2
Sunny with high cloud increasing from late afternoon. NE winds freshening in the afternoon.
24 11.9 24.4 17.2 7.9 69 181 East Nth East 0 0 997.5 1009.3 +11.8
Variable cloud, North to NW winds in the morning turning strong southerly late morning. Winds easing and turning NE from mid afternoon.
25 6.4 23.3 15.7 6.6 37 152 East Nth East 0 0 1009.4 1013.5 +4.1
Mostly sunny with some high cloud, NE winds becoming fresh later in the afternoon.
26 13.2 24.1 18.3 3.5 21 79 East Nth East 0 0 1005.2 1011.1 -5.9
Overcast with light N to NE winds
27 17.5 29.0 23.4 11.8 39 271 North Nth East 0 0 989.6 1005.1 -15.5
Mostly overcast with a few breaks. Warm north to NE wind.
28 9.3 21.3 15.0 10.7 48 245 South Sth West 2.0 27.5 981.2 1012.8 +31.6
Overcast with periods of rain, southerly winds strong for a time.
29 8.3 19.9 14.8 9.7 37 215 East Nth East 0 0 1013.2 1023.3 +10.1
Sunny with fresh NE winds.
30 14.0 25.1 18.6 7.9 34 182 East Nth East 0 0 1006.9 1022.4 -15.5
Mostly overcast with high cloud, NE winds, light in the afternoon.
31 11.4 22.6 17.3 6.3 35 144 East Nth East 0 0 1009.7 1015.3 +5.6
Mostly cloudy with NE wind.

December 2010 Temperature Graph
December 2010 Wind Dir Graph
December 2010 Wind Dir % Graph
December 2010 Wind Speed Graph
December 2010 Rainfall Graph
December 2010 Barograph
December 2010 Humidity Graph