My December
Temperature: December may have seemed a warm month as I recorded 3 days where the temperature exceeded 30C which is a record for my station. Previous December's having temperatures exceeding 30C for just 1 day were 2000 on the 14th, 2002 on the 31st, 2003 on the 14th and 2006 on the 12th. Despite this, the mean maximum temperature for December 2007 was 21.6C, just above my average December mean maximum of 21.0C. The average for the month was 16.0C, above my December average of 15.1C. The warmest December I've recorded was 2005 with an average of 16.8C and the coldest 2006 with 13.1C. The maximum temperature for the month was 33.5C on the 16th, a record maximum December temperature for my station. The minimum temperature was 5.3C on the 27th after a southerly change the previous day. The coolest December temperature I've recorded was 1.3C in the 2nd December 2006.
Wind: The monthly wind run of 6102 km close to my December average of 6169km (records from 2001) The windiest December was 2006 with 6877km and the least windy 2001 with 5376km. Maximum gust was 48km/h from the NE which is unusual. The only other time this year I've recorded similar speeds from the NE was the 30th June when I recorded a 50km/h gust Prevailing wind direction was north east recorded 51% of the month, south 29%, north 6%, south west 6%, nor'west and west 3% and 2% from the SE.
Rainfall: I recorded near average rainfall this December with 69.8mm, the average being 63.9mm. This month also had the highest 10 minute rainfall total for the year with 3.6mm on the 26th with also coincided with the highest daily total of 20.6mm. The wettest December I've recorded was 2004 with 137.8mm closely followed by 2006 with 135.8mm. The lowest total was just 2mm on 1 day in December 2003.
December 2007 Summary Temperature |
|
---|---|
Mean | 16.0 C |
Mean Maximum | 21.6 C |
Mean Minimum | 11.6 C |
Maximum High | 33.5 C (16th) |
Maximum Low | 18.0 C (11th) |
Minimum High | 14.9 C (26th) |
Minimum Low | 5.3 C (27th) |
Wind Speed and Direction | |
Maximum Gust | 48 km/h (8th) |
Mean | 8.3 km/h |
Wind Run | 6102 km |
Max Daily Windrun | 370 km (8th) |
Prevailing Direction | North East |
Barometer | |
Maximum | 1031.8 hPa (13th) |
Minimum | 994.0 hPa (25th) |
Mean | 1016.6 hPa |
Max Daily Change | +20.2 hPa (28th) |
Rainfall | |
Days with Measured Rainfall (Greater than 0.2mm) | 12 |
Max Daily Rainfall | 20.6 mm (26th) |
Monthly Rainfall | 69.8 mm |
Humidity | |
Maximum | 96 % (14th) |
Minimum | 26 % (24th) |
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 | 10.1 | 20.6 | 13.7 | 6.0 | 32 | 141 | North East | 0.6 | 2.6 | 1007.1 | 1013.3 | +6.2 |
Sunny in the morning. Cloud increasing in the afternoon with drizzle by evening and showers later at night. | ||||||||||||
2 | 10.7 | 16.6 | 13.2 | 4.3 | 24 | 102 | North East | 0.2 | 0.4 | 1012.9 | 1015.7 | +2.8 |
Drizzle in the morning. Overcast with NE winds. | ||||||||||||
3 | 12.1 | 25.0 | 16.3 | 8.2 | 32 | 194 | North East | 0 | 0 | 1010.6 | 1020.6 | +10.0 |
Morning low cloud clearing, NE winds. A southerly change after midday but remaining mild and dry. | ||||||||||||
4 | 9.5 | 18.0 | 14.5 | 10.6 | 46 | 249 | North East | 0 | 0 | 1019.1 | 1022.7 | -3.6 |
Morning cloud clearing with fresh NE winds. Cloud returning in the evening. | ||||||||||||
5 | 14.4 | 25.8 | 19.2 | 7.4 | 33 | 167 | North East | 0 | 0 | 1010.1 | 1019.6 | -9.5 |
Morning cloud clearing and NE winds easing by midday. Sunny and warm in the afternoon. | ||||||||||||
6 | 7.6 | 16.3 | 13.1 | 11.0 | 45 | 259 | South | 0 | 0 | 1012.3 | 1031.2 | +18.9 |
Overcast for much of the say with a cool southerly wind. Cloud breaking later in the afternoon and the southerly dying away. | ||||||||||||
7 | 6.9 | 17.5 | 12.5 | 6.9 | 36 | 163 | North East | 0 | 0 | 1023.9 | 1030.6 | -6.7 |
Morning cloud breaking and clearing. Sunny with NE wind. | ||||||||||||
8 | 11.1 | 18.4 | 14.7 | 15.7 | 48 | 370 | North East | 0 | 0 | 1020.4 | 1024.2 | -3.8 |
Morning cloud breaking and mostly sunny with a fresh NE wind (the 4th windiest day of the year to date). Cloud increasing in the evening with a little drizzle. | ||||||||||||
9 | 13.8 | 24.3 | 18.2 | 6.8 | 32 | 161 | North East | 0.2 | 0.4 | 1019.6 | 1022.5 | +2.9 |
Light morning showers and cloud clearing during the morning to a sunny and mild day with light NE winds. Becoming overcast with a southerly change in the evening with a little drizzle. | ||||||||||||
10 | 13.1 | 23.0 | 17.7 | 9.0 | 35 | 212 | North East | 0.2 | 0.8 | 1017.2 | 1022.5 | -5.3 |
Southerly with low cloud and showers in the morning. Showers clearing early afternoon with broken high cloud and NE winds. | ||||||||||||
11 | 18.0 | 32.4 | 23.7 | 5.8 | 24 | 135 | North East | 0 | 0 | 1015.1 | 1018.2 | +3.1 |
Some high cloud with light NE winds. The warmest December temperature recorded to date and the warmest day since February 26th. | ||||||||||||
12 | 16.1 | 27.2 | 20.1 | 3.1 | 21 | 73 | North East | 0.4 | 3.8 | 1015.7 | 1018.2 | -2.5 |
Cloudy, mild and humid with showers and light NE winds. | ||||||||||||
13 | 11.1 | 18.7 | 13.5 | 13.0 | 39 | 308 | South | 0.6 | 16.6 | 1017.6 | 1031.8 | +14.2 |
Overcast with showers and cool southerly winds. | ||||||||||||
14 | 11.0 | 16.4 | 13.2 | 7.3 | 33 | 172 | North East | 0.4 | 2.8 | 1025.1 | 1031.6 | -6.5 |
Low cloud with some morning showers. NE winds. | ||||||||||||
15 | 13.7 | 20.5 | 16.7 | 11.8 | 44 | 278 | North East | 0.2 | 0.2 | 1015.6 | 1024.9 | -9.3 |
Morning low cloud and drizzle clearing by early afternoon to a sunny day, NE winds. | ||||||||||||
16 | 14.4 | 33.5 | 23.3 | 3.0 | 24 | 71 | North West | 0 | 0 | 1010.6 | 1016.5 | -5.9 |
High cloud with light winds, tending nor'west in the afternoon. A new December record for my station just 5 days after the 2006 December record was broken on the 11th. The Metservice record temperature for December in Christchurch is 35.4C recorded in 1975. | ||||||||||||
17 | 12.6 | 31.8 | 20.7 | 9.7 | 42 | 230 | South | 0.2 | 0.4 | 1005.9 | 1013.6 | +7.7 |
Variable cloud in the morning with NW winds. A change later in the afternoon to a cooler southerly and becoming overcast. Showers at night. | ||||||||||||
18 | 10.6 | 15.6 | 12.2 | 4.1 | 25 | 46 | South | 1.2 | 13.0 | 1012.3 | 1017.9 | +5.6 |
Overcast with showers and light southerly winds. A change to NE winds mid afternoon. | ||||||||||||
19 | 11.2 | 17.8 | 14.0 | 5.3 | 29 | 125 | North East | 0 | 0 | 1011.3 | 1016.5 | -5.2 |
Overcast with some drizzle in the morning. Cloud breaking for a time later in the afternoon. NE winds. | ||||||||||||
20 | 10.4 | 19.1 | 13.3 | 6.8 | 30 | 161 | South | 1.0 | 5.8 | 1012.2 | 1023.2 | +11.0 |
Showers in the morning. Cloud breaking in the afternoon with some sunny intervals. Southerly winds. | ||||||||||||
21 | 9.8 | 18.4 | 14.1 | 6.4 | 34 | 152 | North East | 0 | 0 | 1022.8 | 1025.4 | +2.6 |
Broken cloud, NE wind, cool at times. | ||||||||||||
22 | 12.2 | 19.0 | 15.6 | 12.1 | 41 | 285 | North East | 0 | 0 | 1020.4 | 1026.1 | -5.7 |
Morning cloud breaking to a sunny day. Fresh NE winds. | ||||||||||||
23 | 14.6 | 21.1 | 17.5 | 12.7 | 45 | 301 | North East | 0 | 0 | 1004.9 | 1020.3 | -15.4 |
Morning cloud breaking to a sunny day with fresh NE winds. | ||||||||||||
24 | 13.4 | 28.2 | 19.7 | 6.9 | 34 | 163 | North East | 0 | 0 | 997.0 | 1004.9 | -7.9 |
Sunny and warm in the morning. Cloud increasing and light showers around midday. Cloud breaking to a sunny afternoon with NE winds turning warmer nor'west later followed by a cooler southerly change in the evening. | ||||||||||||
25 | 10.6 | 23.9 | 16.0 | 8.6 | 32 | 203 | South | 0 | 0 | 994.0 | 1002.7 | -8.7 |
Southerly winds in the morning. Cloud breaking but some high cloud remaining. Sunny with NE winds later in the afternoon. | ||||||||||||
26 | 8.3 | 14.9 | 11.5 | 10.7 | 41 | 253 | South | 3.6 | 20.6 | 997.5 | 1013.2 | +15.7 |
Early southerly cold change with showers, some heavy. Showers clearing and cloud breaking in the afternoon. | ||||||||||||
27 | 5.3 | 22.4 | 14.4 | 6.2 | 33 | 145 | North East | 0 | 0 | 1001.2 | 1013.0 | -11.8 |
Sunny but cool morning. High cloud increasing during the afternoon. NE winds. | ||||||||||||
28 | 9.0 | 19.3 | 13.5 | 9.0 | 44 | 212 | North East | 0.6 | 2.8 | 1002.9 | 1023.1 | +20.2 |
Morning showers with southerly winds. Cloud breaking in the afternoon with NE winds. | ||||||||||||
29 | 12.4 | 18.9 | 15.4 | 12.1 | 37 | 284 | North East | 0 | 0 | 1019.3 | 1023.3 | -4.0 |
Broken cloud with haze and a breezy Ne wind. | ||||||||||||
30 | 13.5 | 24.9 | 18.5 | 8.0 | 38 | 190 | North East | 0 | 0 | 1013.3 | 1019.7 | -6.4 |
Some high cloud, becoming overcast late afternoon with a few spots of rain. Southerly change at night but remaining dry. | ||||||||||||
31 | 12.1 | 20.3 | 15.1 | 9.8 | 41 | 232 | South | 0 | 0 | 1020.4 | 1029.7 | +9.3 |
Morning cloud breaking in the afternoon with southerly winds turning NE. |