Climate averages 1991–2020
Viseu weather
in September.
A warm, moderately wet month: the 3rd warmest and the 4th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Viseu: daytime highs average 24.3°C and nights cool to about 13.7°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 66 mm of rain on roughly 7 days, which makes September a moderately wet month (the 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 30 min on an average September day.
The nearest other city in this atlas is Aveiro (62 km away). In September its highs average 25.1°C, 0.8°C warmer than Viseu, with 51 mm of rain.
Among the 12 cities listed in Portugal, Viseu ranks joint 6th of 12 for the warmest September highs and 11th of 12 for the driest September (rainfall, lowest first). The mean September high of those 12 cities is 24.6°C; Viseu is 0.3°C cooler than that mean.
From September to October, average highs fall by 5.4°C to 18.9°C, and monthly rainfall rises from 66 mm to 168 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Viseu climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 10.5°C3.1°C | 3.1°C | 152 | 11.6 | 9.610 h |
| February | 12.0°C3.4°C | 3.4°C | 102 | 9.3 | 10.611 h |
| March | 15.0°C5.4°C | 5.4°C | 115 | 10.6 | 11.912 h |
| April | 16.6°C7.1°C | 7.1°C | 118 | 12.8 | 13.313 h |
| May | 20.0°C9.9°C | 9.9°C | 98 | 11.6 | 14.414 h |
| June | 24.2°C13.1°C | 13.1°C | 40 | 6.2 | 15.015 h |
| July | 27.6°C15.4°C | 15.4°C | 19 | 3.6 | 14.815 h |
| August | 27.9°C15.8°C | 15.8°C | 26 | 4.6 | 13.814 h |
| September, selected | 24.3°C13.7°C | 13.7°C | 66 | 7.1 | 12.513 h |
| October | 18.9°C10.5°C | 10.5°C | 168 | 12.2 | 11.211 h |
| November | 13.6°C6.4°C | 6.4°C | 150 | 12.7 | 10.010 h |
| December | 11.1°C4.1°C | 4.1°C | 160 | 11.6 | 9.39 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Aveiro in SeptemberPortugal · 62 kmHigh 25.1°C · Low 15.8°C · 51 mm rain
- Coimbra in SeptemberPortugal · 67 kmHigh 26.3°C · Low 15.0°C · 49 mm rain
- Porto in SeptemberPortugal · 80 kmHigh 24.1°C · Low 15.7°C · 64 mm rain
- Braga in SeptemberPortugal · 108 kmHigh 23.8°C · Low 13.7°C · 79 mm rain
- Leiria in SeptemberPortugal · 127 kmHigh 25.3°C · Low 15.7°C · 41 mm rain
- Cáceres, Spain in SeptemberSpain · 186 kmHigh 27.4°C · Low 16.4°C · 34 mm rain
- Ourense in SeptemberSpain · 186 kmHigh 24.4°C · Low 13.5°C · 48 mm rain
- Vigo in SeptemberSpain · 187 kmHigh 22.0°C · Low 14.6°C · 88 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Viseu) is explained once on the Viseu year overview and on the Sources, method and limits page.