My September.
Temperature:
The mean temperature for the month was 10.3C was above my September average of 9.7C and the third warmest I've recorded. The warmest September was 2002 and 2006 with an average temperature of 11.1C, the coldest, 2001 with 8.3C.
The warmest day was the 29th with 24.0C, the minimum was -1.2C on the 22nd. My coldest September temperature to date is -2.9C in 2001, the warmest 25.0C in 2008
There were 2 days with a temperature at or below 0, my September average is 3. There was 1 day where the maximum temperature for the day was less than 10C, my average is 3. Twenty Two days reached or exceeded 15C, my September average is 15. There were 7 days that reached or exceeded 20C, my average is 6.
Wind: (Records from 2001)
The monthly wind run of 4575km is 95% of my September average of 4834km making this September the 3rd least windy I've recorded. The windiest September was 2003 with 5356km, the least windy 2004 with 4485km. The highest gust was 53km/h from the south south west on the 23rd.
Rainfall:
September had 42.5mm of rain over 12 days, 86% of my 49.3mm September average. The wettest day was the 12th with 14.5mm. My wettest September day was 19th September 2005 with 48.8mm. The wettest September was 2003 with 100mm, the driest, 2006 with just 5mm.
Barometer: (Records from 2006)
The average pressure for the month was below my September average of 1014.2 hPa with 1003 hPa. Maximum pressure change of 21.1 hPa equals my September average.
NIWA monthly climate summaries can be seen here.
| September 2010 Summary Temperature |
|
|---|---|
| Mean | 10.3 C |
| Mean Maximum | 16.7 C |
| Mean Minimum | 4.9 C |
| Maximum High | 24.0 C (29th) |
| Maximum Low | 9.8 C (29th) |
| Minimum High | 11.4 C (9th) |
| Minimum Low | -1.2 C (22nd) |
| Wind Speed and Direction | |
| Maximum Gust | 53 km/h (23rd) |
| Mean | 6.8 km/h |
| Wind Run | 4575 km |
| Max Daily Windrun | 257 km (6th) |
| Prevailing Direction | East Nth East |
| Barometer | |
| Maximum | 1030.0 hPa (8th) |
| Minimum | 977.5 hPa (17th) |
| Mean | 1003.0 hPa |
| Max Daily Change | - 21.1 hPa (6th) |
| Rainfall | |
| Days with Measured Rainfall (Greater than 0.2mm) |
12 |
| Max Daily Rainfall | 14.5 mm (12th) |
| Monthly Rainfall | 42.5 mm |
| Humidity | |
| Maximum |
100 % (1st) |
| Minimum | 25 % (26th) |
| September 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 | 1.9 | 11.7 | 7.5 | 7.1 | 32 | 163 | East Nth East | 0 | 0 | 1008.1 | 1020.1 | -12.0 |
| A sunny day for the first day of Spring. NE winds. | ||||||||||||
| 2 | 5.5 | 17.5 | 11.0 | 8.2 | 36 | 186 | East Nth East | 0 | 0 | 988.5 | 1007.6 | -19.1 |
| Morning cloud breaking to a mostly sunny afternoon, NE winds turning mild NW in the afternoon and light southerly in the evening. A few spots of rain in the evening. | ||||||||||||
| 3 | 0.8 | 12.6 | 5.1 | 7.2 | 45 | 161 | South Sth West | 0.5 | 7.0 | 990.9 | 1009.4 | +18.5 |
| Morning frost. Becoming cloudy with a cold southerly change at around midday with rain and some sleet. | ||||||||||||
| 4 | ||||||||||||
| No data today due to a 7.1 earthquake cutting the power from 4:35am to 6pm. Clear and sunny with light breezes tending NE later in the afternoon. | ||||||||||||
| 5 | 4.2 | 17.6 | 10.9 | 6.6 | 47 | 150 | East Nth East | 0 | 0 | 997.7 | 1018.8 | -21.1 |
| Mostly cloudy with a 'nor'west arch' of cloud. NE winds turning gusty NW at times. | ||||||||||||
| 6 | 8.8 | 21.8 | 14.2 | 11.3 | 48 | 257 | North Nth West | 0 | 0 | 994.5 | 1011.7 | +17.2 |
| Sunny with warm NW winds, gusty at times. A cold southerly change in the afternoon witn increasing cloud. | ||||||||||||
| 7 | 8.1 | 15.1 | 10.0 | 6.0 | 24 | 138 | East Nth East | 0.5 | 0.5 | 1011.5 | 1023.0 | +11.5 |
| Mostly cloudy with some light rain or drizzle. | ||||||||||||
| 8 | 8.5 | 12.1 | 9.5 | 4.4 | 22 | 100 | East Nth East | 0.5 | 3.5 | 1023.2 | 1030.0 | +6.8 |
| Light rain and drizzle in the morning, clearing in the afternoon. NE winds. | ||||||||||||
| 9 | 7.9 | 11.4 | 9.1 | 6.8 | 24 | 154 | East Nth East | 0.5 | 2.0 | 1017.9 | 1027.5 | -9.6 |
| Light rain and drizzle early morning and evening, cloudy with NE winds. | ||||||||||||
| 10 | 7.9 | 15.2 | 10.0 | 5.0 | 25 | 113 | East Nth East | 0.5 | 1.5 | 1006.9 | 1017.6 | -10.7 |
| Morning drizzle and light rain. Cloud clearing to a sunny afternoon, southerly breezes turning north to NE. | ||||||||||||
| 11 | 7.8 | 20.4 | 12.5 | 7.0 | 30 | 159 | East Nth East | 0 | 0 | 1005.2 | 1012.0 | -6.8 |
| Morning cloud breaking with mild north to NW winds for a time. Overcast with cooler NE winds later in the afternoon. | ||||||||||||
| 12 | 9.6 | 16.4 | 11.7 | 7.7 | 29 | 175 | South Sth West | 1.5 | 14.5 | 1000.8 | 1005.1 | -4.3 |
| Morning cloud breaking for a time but becoming overcast in the afternoon with rain from evening. Southerly winds. | ||||||||||||
| 13 | 9.3 | 17.4 | 10.7 | 8.5 | 30 | 194 | South Sth West | 0.5 | 4.0 | 999.5 | 1007.6 | -8.1 |
| Morning light rain and southerly winds. Cloud clearing for a time early afternoon but returning with a cool NE change. | ||||||||||||
| 14 | 6.4 | 19.8 | 11.1 | 7.8 | 44 | 175 | East Nth East | 1.0 | 4.0 | 994.6 | 1006.3 | +11.7 |
| Broken cloud during the day with NE winds turning mild NW in the afternoon. A cold southerly change in the evening with showers. | ||||||||||||
| 15 | 2.7 | 12.8 | 7.9 | 4.7 | 31 | 108 | East Nth East | 0.5 | 1.5 | 1001.9 | 1011.1 | -9.2 |
| Showers clearing before dawn. Mostly sunny with cool NE winds in the afternoon. | ||||||||||||
| 16 | 3.0 | 16.0 | 9.3 | 4.8 | 28 | 110 | North Nth East | 0 | 0 | 982.3 | 1001.6 | -19.3 |
| Cloudy for much of the day, north to NE winds. | ||||||||||||
| 17 | 3.3 | 14.0 | 9.2 | 8.6 | 47 | 195 | North Nth West | 0.5 | 0.5 | 977.5 | 982.4 | -4.9 |
| Early showers clearing mid morning with variable cloud during the day. North to NW winds, gusty at times. Lowest barometer pressure for the year to date. | ||||||||||||
| 18 | 0.8 | 16.1 | 7.6 | 8.4 | 46 | 191 | South Sth West | 0 | 0 | 978.1 | 992.6 | +14.5 |
| Variable cloud during the day. NE wind in the morning turning NW in the afternoon and cold southerly in the evening along with some light showers. | ||||||||||||
| 19 | -0.3 | 15.6 | 6.9 | 2.3 | 24 | 53 | East Nth East | 0 | 0 | 993.0 | 1000.0 | +7.0 |
| Some cloud but mostly sunny with north to NE winds. | ||||||||||||
| 20 | 2.3 | 16.9 | 8.9 | 5.4 | 37 | 123 | East Nth East | 0 | 0 | 983.9 | 999.0 | -15.1 |
| Some cloud but mostly sunny. NE winds turning NW then southerly in the evening. | ||||||||||||
| 21 | 2.6 | 15.0 | 8.5 | 6.0 | 42 | 138 | South Sth West | 0.5 | 3.0 | 984.2 | 994.8 | +10.6 |
| Clound increasing in the afternoon, showers in the eveining. Southerly breezes during the day, wind picking up later in the evening with the showers. | ||||||||||||
| 22 | -1.2 | 16.4 | 8.2 | 7.3 | 39 | 166 | North Nth West | 0.5 | 0.5 | 983.0 | 990.0 | -16.0 |
| Early showers clearing before dawn leaving a dusting of snow on the Port Hills. Winds turning north to NW followed by another brief strong southerly change late in the evening. | ||||||||||||
| 23 | 3.4 | 12.7 | 8.0 | 8.9 | 53 | 203 | South Sth West | 0 | 0 | 986.0 | 1004.4 | +18.4 |
| Sunny with cool southerly winds easing in the evening and turning NE. | ||||||||||||
| 24 | 3.0 | 19.1 | 11.0 | 7.2 | 50 | 164 | North Nth West | 0 | 0 | 990.8 | 1004.0 | -13.2 |
| Variable cloud, gusty nor'west winds for a time in the afternoon. | ||||||||||||
| 25 | 3.9 | 20.3 | 12.9 | 7.8 | 36 | 177 | North Nth West | 0 | 0 | 998.4 | 1006.7 | +8.3 |
| Some high cloud but mostly sunny with north to nor'west winds. | ||||||||||||
| 26 | 9.6 | 23.1 | 17.1 | 9.4 | 49 | 205 | North Nth West | 0 | 0 | 1002.3 | 1014.8 | +12.5 |
| Fine and clear with mild north to NW winds | ||||||||||||
| 27 | 3.5 | 22.1 | 12.7 | 5.5 | 35 | 127 | East Nth East | 0 | 0 | 1013.2 | 1020.2 | -7.0 |
| Sunny, NE winds. | ||||||||||||
| 28 | 5.3 | 21.1 | 14.0 | 6.0 | 37 | 137 | East Nth East | 0 | 0 | 1005.8 | 1014.0 | -8.2 |
| North to NE winds, briefly NW in the morning. Overcast from late morning, clearing in the evening. | ||||||||||||
| 29 | 9.8 | 24.0 | 15.3 | 7.9 | 31 | 181 | East Nth East | 0 | 0 | 1005.3 | 1010.8 | +5.5 |
| Cloud increasing in the afternoon with a southerly change and a few spots rain in the afternoon and evening. | ||||||||||||
| 30 | 7.8 | 19.3 | 11.6 | 5.9 | 40 | 134 | South West | 0 | 0 | 999.8 | 1009.3 | -9.5 |
| Cloud morning and evening. A cool southerly change in the afternoon. | ||||||||||||
