Blenheim
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Blenheim Weather in September

September in Blenheim averages 15°C (59°F) during the day and 6°C (43°F) at night. Quite a bit of rainfall is typical this month, with around 84 mm (3.3 in) on average. An umbrella is a good idea.

Rainfall in Blenheim in September

Typically around 10 days of rainfall are expected, averaging 84 mm (3.3 in) for the month. Rainfall intensity is on the higher side this month. Expect more substantial showers rather than light, passing rain.

Temperature in Blenheim in September

Expect highs of 15°C (59°F) in Blenheim in September, with nights dropping to around 6°C (43°F). The difference between afternoon and evening temperatures is usually noticeable. Nights fall to 6°C (43°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep.

Sunshine in Blenheim in September

The month brings about 189 hours of sunlight, offering a comfortable mix of sun and overcast.

Should you favor a climate that's both dry and comfortably warm, January, February, March and December typically offer the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

Blenheim Temperature in September

Min Temperature
6°C (43°F)
Max Temperature
15°C (59°F)
Chance of Rain
34%
Precipitation
84 mm (3.3 in)
Rainy days
10 days
Humidity
80% *
Sunshine
189 hours *
Percentage Sunshine
*
* Data from: Nelson, New Zealand (62 KM, 38 Miles).

Blenheim Weather by Month

Pick a month to see the average temperature, rainfall and sunshine in Blenheim - and find the best time to visit.

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Blenheim typically stay consistent throughout September, with daily highs averaging around 15°C (59°F). Nights are cool, with lows around 8°C (46°F).

Average temperatures in September

Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

Historical weather records for Blenheim in September

Browse day-by-day weather records for Blenheim spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Blenheim historical weather extremes in September

Based on 50 years of weather observations in Blenheim between 1976 and 2026, these are the recorded extremes.

  • The warmest day in September was on September 24, 1996, with a maximum of 22°C (72°F).
  • The coldest September day was on September 27, 1993, with a maximum of 8°C (46°F).
  • Nighttime temperatures dropped to 0°C (32°F) on September 7, 1997, marking the coldest September night on record.

Best Places in New Zealand in September

Find out more about the weather in New Zealand and which places have the best travel conditions in this month. See all of New Zealand in September →

perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

What to Wear in Blenheim in September

The weather can be unpredictable in September, so pack clothes you can easily mix and match. You could bring jeans, other long pants, and a few t-shirts. A light jacket or light sweater will be pleasant for the cooler moments. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. Sunglasses could come in handy during the sunnier parts of your trip.

What To Do in Blenheim in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

  • Swimming
    5/10
  • Cycling
    6/10
  • Walking
    6/10
  • Camping
    4/10
  • Outdoor sports
    9/10

Blenheim 3-Day Forecast

More climate data for Blenheim

Popular in September

Where to go in September - average daytime high across popular destinations.

Bucket list

Need travel inspiration? Check out our bucket list articles and be inspired.