Viseu weather in December

In December, Viseu sees average daytime highs of 11°C and overnight lows near 5°C, with 160 mm of precipitation across 11.6 wet days and about 9.1 hours of daylight. It is the 11th-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 11°C through the month. The sky is clear or mostly clear about 32% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 18 min at the start of December to 9 h 06 min by month's end. Set against the rest of the year, December is Viseu's 12th-clearest and 2nd-windiest month. For the whole year in context, see Viseu's year-round climate.

Daytime high
11°
11th warmest
Overnight low
3rd coldest
Precipitation
160 mm
11.6 wet days
Daylight
9 h 06 min
7:55 AM – 5:01 PM
Cloud cover
62%
12th clearest
Wind
10 km/h
2nd windiest
Solar energy
1.66 kWh/m²
Travel score
2.7
out of 10

Viseu is city seat of Viseu municipality.

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 11°C through the month.

A typical December day in Viseu reaches about 11°C in the afternoon and slips back to 5°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 8°C and 14°C. Set against its neighbours, December runs about 3°C cooler than November and on par with January.

-5°10°15°151015202531
Avg high (°C)Avg low (°C)
1125
2125
3125
4125
5125
6125
7115
8115
9115
10115
11115
12115
13115
14115
15115
16115
17115
18115
19115
20114
21114
22114
23114
24114
25114
26114
27114
28114
29114
30114
31114

Viseu weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan11° / 15211.60.59.42.5
Feb12° / 1029.30.310.43.3
Mar15° / 11510.6011.74.5
Apr17° / 11812.8013.14.9
May20° / 10°9811.6014.26.1
Jun23° / 13°406.2014.97.7
Jul27° / 15°193.7014.68.2
Aug27° / 15°264.6013.68.0
Sep24° / 13°667.1012.37.6
Oct19° / 10°16812.2010.95.7
Nov14° / 15012.70.19.73.7
Dec11° / 16011.60.19.12.7

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 32% of the time in December, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 9% of December, with mostly cloudy or overcast conditions the remaining 59%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14060
24060
33961
43961
54060
64060
74060
84060
94060
104159
114060
124060
134159
144159
154159
164258
174159
184357
194357
204258
214258
224258
234159
244060
254060
264060
274060
283961
293961
303961
313961

Chance of precipitation in December

Any precipitation

Viseu gets around 160 mm of rain and snow over 11.6 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 38% and peaks near 42% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202531
Rain chance (%)
138
237
337
436
536
636
735
835
935
1035
1135
1235
1336
1436
1536
1636
1736
1836
1937
2037
2138
2238
2339
2440
2540
2641
2741
2841
2942
3042
3142

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1991
2991
31000
41000
51000
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

Wind in December

Winds average 10 km/h in December.

Across December, daily wind ranges from about 10 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 18 min at the start of December to 9 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 7:42 AM to 8:01 AM, and sunset from 5:00 PM to 5:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.37:425:00
29.37:435:00
39.37:445:00
49.27:455:00
59.27:465:00
69.27:475:00
79.27:485:00
89.27:495:00
99.27:505:00
109.27:505:00
119.17:515:00
129.17:525:00
139.17:535:00
149.17:535:00
159.17:545:01
169.17:555:01
179.17:555:01
189.17:565:02
199.17:575:02
209.17:575:02
219.17:585:03
229.17:585:03
239.17:595:04
249.17:595:04
259.17:595:05
269.18:005:05
279.18:005:06
289.18:005:07
299.18:015:07
309.18:015:08
319.18:015:09

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.66 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.66 kWh/m² to a high of 7.25 kWh/m² in July across the year — December's 1.66 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.8Dim
21.8Dim
31.8Dim
41.8Dim
51.8Dim
61.7Dim
71.7Dim
81.7Dim
91.7Dim
101.7Dim
111.7Dim
121.7Dim
131.7Dim
141.7Dim
151.7Dim
161.7Dim
171.7Dim
181.6Dim
191.6Dim
201.6Dim
211.6Dim
221.6Dim
231.6Dim
241.6Dim
251.6Dim
261.6Dim
271.6Dim
281.6Dim
291.6Dim
301.6Dim
311.6Dim
Planning a trip in December

Hazard calendar for Viseu

In seasonPeak

In December, Viseu sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Viseu's rainy season runs October–May, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is December a good time to visit Viseu?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

2.7
Sightseeing
11th-best month of the year
0.0
Beach & pool
11th-best month of the year

December is a weaker month for outdoor sightseeing in Viseu.

What to pack for Viseu in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Viseu sees daytime highs around 11°C and nights near 5°C. Pack a warm layer. Worth having: rain gear. About 12 days see rain.

a warm layerrain gear

UV index in Viseu in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Viseu peaks around July 13 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJul 13UV 9Dec 20UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5High
Apr7High
May7High
Jun9Very high
Jul9Very high
Aug9Very high
Sep6High
Oct5Moderate
Nov2Moderate
Dec2Low

Air quality in Viseu in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Viseu is worst in October — around 29 µg/m³ PM2.5 (moderate), about 3.9× the cleanest month (November, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateModerateGoodOct 1228 µg/m³Nov 237 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar13Moderate
Apr11Good
May8Good
Jun21Moderate
Jul9Good
Aug24Moderate
Sep23Moderate
Oct29Moderate
Nov7Good
Dec7Good
Location & terrain

Where is Viseu?

Viseu sits at 40.7°N, 7.9°W, 469 m above sea level, in Portugal. The nearest listed city is Arouca, 41 km away.

Topography around Viseu

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Viseu.

Within 3 km, the terrain around Viseu has only modest variations in elevation — a maximum elevation change of 165 m around an average of 466 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 814 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,993 m.

The land around Viseu is covered by trees (45%) and artificial surfaces (35%) within 3 km, trees (56%) and grassland (36%) within 16 km, and trees (48%) and grassland (41%) within 80 km.

3 km
165 m
16 km
814 m
80 km
1,993 m
treesshrubsgrasslandcroplandartificial surfaceswater
December weather nearby: Arouca 41 km · Covilhã 54 km · São João da Madeira 56 km · Guarda 56 km · Baião 57 km · Sequeira 59 km · Feira 61 km · Vilar 61 km

Portugal travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / E / F
230 V · 50 Hz
Prices
≈ 60% of US
price level, 2025
GDP per capita
$32,082
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
95%
of population, 2024
Homicide rate
0.7
per 100k, 2022
Road deaths
8.2
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 612
Religion
Catholic 68%not applicable 13%no religion 12%no response 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Viseu (40.6617°, -7.909°, elevation 469 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).