A typical September based on the past 10 years of my records (2009 to 2018);

  • An average temperature of 9.8C
    • Maximum temperature expected about 24C.
    • Minimum temperature expected about -1.0C.
    • There are 2 frosts on average, air temperature at or below 0C.
    • One day fails to reach 10C.
    • Sixteen days are expected to reach or exceed 15C
    • Five days on average are expected to reach or exceed 20C.
  • Wind run would be around 4800km with the windiest day expected to have a wind run of 350km.
    • Maximum wind gust would be in the region of 65km/h.
  • There would be rain on 10 days with the monthly total of around 42mm.
    • Maximum daily rainfall is expected to be around 15mm

Rain totals for the month and year along with temperature and wind comparisons can be found here.

 September Daily Observations
TemperatureWindRainfallBarometer
DateMinMaxMeanMean
(Km/h)
Gust
(Km/h)
Run (km)Prevailing Dir10 Minute Max (mm)Total (mm)Min (hPa)Max (hPa)Change (hPa)
1 1.2 21.2 10.6 2.9 28 66 East Nth East 0 0 1016.0 1023.6 -7.6
Sunny and mild with light winds tending NE.
2 3.9 15.3 10.2 8.1 39 185 East Nth East 0 0 1017.3 1022.5 -5.2
Sunny with a freshening NE wind in the afternoon.
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3 3.4 15.7 9.6 3.4 23 76 East Nth East 0 0 1014.8 1018.6 -3.8
Fog and low cloud in the morning clearing to a sunny day with  few clouds. Light NE winds.
4 6.7 11.0 9.8 7.0 31 159 East Nth East 0.8 9.8 997.9 1014.8 -16.9
Low cloud and drizzle from midday with showers in the afternoon, NE wind.
5 8.3 10.4 9.1 9.9 35 227 South West 0.2 1.2 988.9 997.5 -8.6
Light rain and drizzle in the morning clearing for a while but returning later in the afternoon. Southerly winds.
6 6.5 9.0 7.9 15,6 46 358 South West 1.2 9.0 988.6 1001.4 +12.8
Overcast with showers and southerly winds.
7 0.0 10.9 5.9 5.2 30 120 South Sth West 0.4 0.6 1001.3 1005.3 +4.0
Showers clearing by dawn with cloud breaking to a sunny afternoon. Cool southerly winds.
8 -1.4 9.6 4.1 4.0 22 90 South Sth West 0 0 1002.0 1006.5 +4.5
Morning frost. Overcast from early morning with light showers later. Light southerly winds.
9 2.8 10.4 5.9 3.1 24 71 East 0 0 1005.9 1008.1 -2.2
Overcast and cold with variable winds in the morning turning NE in the afternoon.
Snow risk to North Island high routes; temperatures plummet in south
10 2.6 11.5 7.5 7.9 38 172 East Nth East 0 0 1000.0 1007.3 -7.3
Sunny with fresh cool Ne wind.
11 1.9 12.8 6.9 5.6 28 128 South Sth West 0 0 999.6 1010.4 +10.8
Morning cloud breaking to a sunny afternoon with a cool southerly wind turning NE in the evening.
12 1.4 20.5 11.7 4.8 34 109 East Nth East 0 0 1002.0 1009.7 -7.7
Variable high cloud, mild northerlies from midday.
13 6.9 18.2 11.2 6.6 37 151 South Sth West 0.2 1.2 998.2 1013.5 +15.3
Mild northerly winds in the morning followed by a cold southerly change around 11am with a few afternoon showers.
14 5.3 10.2 7.8 2.7 26 60 East 0.4 8.8 1004.9 1013.6 -8.7
Overcast with low cloud and mist. light rain and drizzle throughout the day. Light winds.
15 7.2 12.8 9.1 6.7 25 152 South West 0.2 3.4 1002.4 1005.4 -3.0
Overcast with low cloud, mist and drizzle in the morning. Cloud breaking to a mostly sunny afternoon with southerly winds turning NE.
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