Slaný weather in December

In December, Slaný sees average daytime highs of 3°C and overnight lows near -1°C, with 37 mm of precipitation across 8.8 wet days and about 7.9 hours of daylight. It is the 11th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 3°C through the month. The sky is clear or mostly clear about 11% of the time in December, and the air most often feels dry.

Daylight stretches from about 8 h 06 min at the start of December to 7 h 54 min by month's end. Set against the rest of the year, December is Slaný's 11th-clearest and 4th-windiest month. For the whole year in context, see Slaný's year-round climate.

Daytime high
11th warmest
Overnight low
-1°
3rd coldest
Precipitation
37 mm
8.8 wet days
Daylight
7 h 48 min
8:05 AM – 3:55 PM
Cloud cover
76%
11th clearest
Wind
12 km/h
4th windiest
Solar energy
0.73 kWh/m²
Travel score
0.0
out of 10

Slaný is town in the Czech Republic.

Density
429/km²
people per km²
Founded
1239

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 3°C through the month.

A typical December day in Slaný reaches about 3°C in the afternoon and slips back to -1°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between -2°C and 9°C. Set against its neighbours, December runs about 4°C cooler than November and about 1°C warmer than January.

-10°-5°10°151015202531
Avg high (°C)Avg low (°C)
140
240
340
440
540
640
740
84-1
94-1
104-1
113-1
123-1
133-1
143-1
153-1
163-1
173-1
183-1
193-1
203-1
213-2
223-2
233-2
243-2
253-2
263-2
273-2
283-2
293-2
303-2
313-2

How December really feels in Slaný

Once humidity and wind are folded in, December averages 0 days that feel above 32°C and 31 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
31
wind chill below the day's low

The story in December is cold — wind chill drags the overnight "feels like" below the raw low.

Slaný weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -2°329.14.38.30.0
Feb / -2°267.53.19.70.1
Mar / 389.82.311.51.6
Apr14° / 358.80.413.54.2
May19° / 5911.9015.25.7
Jun22° / 12°7011.8016.16.3
Jul25° / 14°7612015.76.6
Aug24° / 14°6710.5014.36.8
Sep19° / 10°509012.46.1
Oct13° / 429.20.110.53.6
Nov / 388.31.28.80.9
Dec / -1°378.83.97.90.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 12% of December, with mostly cloudy or overcast conditions the remaining 77%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12179
22179
32179
42179
52179
62179
72278
82278
92278
102278
112278
122377
132278
142278
152278
162278
172278
182377
192377
202377
212377
222476
232476
242476
252575
262575
272575
282575
292575
302575
312674

Chance of precipitation in December

Any precipitationSnow

Slaný gets around 37 mm of rain and snow over 8.8 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 29% and peaks near 30% on the wettest days, and about 4 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1268
2269
3279
4279
52810
62810
72810
82910
92910
102911
112911
122912
133012
143012
153013
163013
173013
183014
193014
202914
212914
222914
232914
242814
252814
262814
272814
282914
292913
302913
312913

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 (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in December

Winds average 12 km/h in December.

Across December, daily wind ranges from about 11 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
612calm
712calm
812calm
912calm
1012calm
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze
3112light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 8 h 06 min at the start of December to 7 h 54 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 7:49 AM to 8:11 AM, and sunset from 3:58 PM to 4:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
18.17:493:58
28.17:503:57
38.17:523:57
48.17:533:56
58.07:543:56
68.07:553:56
78.07:563:55
88.07:573:55
97.97:583:55
107.97:593:55
117.98:003:55
127.98:013:55
137.98:023:55
147.98:033:55
157.98:043:55
167.88:053:55
177.88:053:55
187.88:063:56
197.88:073:56
207.88:073:56
217.88:083:57
227.88:083:57
237.88:093:58
247.88:093:58
257.88:093:59
267.88:103:59
277.88:104:00
287.88:104:01
297.98:104:01
307.98:104:02
317.98:114:03

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 0.73 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 0.73 kWh/m² to a high of 5.45 kWh/m² in June across the year — December's 0.73 kWh/m² sits near the bottom.

00.511.52151015202531
Solar energy (kWh/m²)Level
10.8Dim
20.8Dim
30.8Dim
40.8Dim
50.8Dim
60.8Dim
70.8Dim
80.8Dim
90.8Dim
100.7Dim
110.7Dim
120.7Dim
130.7Dim
140.7Dim
150.7Dim
160.7Dim
170.7Dim
180.7Dim
190.7Dim
200.7Dim
210.7Dim
220.7Dim
230.7Dim
240.7Dim
250.7Dim
260.7Dim
270.7Dim
280.7Dim
290.7Dim
300.7Dim
310.8Dim
Planning a trip in December

Is December a good time to visit Slaný?

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

0.0
Sightseeing
11th-best month of the year
0.0
Beach & pool
8th-best month of the year

December is a weaker month for outdoor sightseeing in Slaný.

What to pack for Slaný in December

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

In December, Slaný sees daytime highs around 3°C and nights near -1°C. Pack a warm layer. Worth having: a heavy coat and rain gear. About 9 days see rain.

a warm layera heavy coatrain gear

UV index in Slaný in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 1. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Slaný peaks around June 21 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 21UV 7Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr4Moderate
May6High
Jun7High
Jul7High
Aug6High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low

Air quality in Slaný 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 Slaný is worst in April — around 22 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1022 µg/m³Dec 1515 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb18Moderate
Mar21Moderate
Apr22Moderate
May19Moderate
Jun21Moderate
Jul18Moderate
Aug19Moderate
Sep19Moderate
Oct17Moderate
Nov16Moderate
Dec15Moderate
Location & terrain

Where is Slaný?

Slaný sits at 50.2°N, 14.1°E, 282 m above sea level, in Czechia. The nearest listed city is Kladno, 9.0 km away.

Topography around Slaný

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

Within 3 km, the terrain around Slaný has only modest variations in elevation — a maximum elevation change of 104 m around an average of 289 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 341 m; within 80 km, large variations in elevation — a maximum elevation change of 1,076 m.

The land around Slaný is covered by cropland (55%) within 3 km, cropland (63%) and trees (23%) within 16 km, and trees (45%) and cropland (35%) within 80 km.

3 km
104 m
16 km
341 m
80 km
1,076 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Kladno 9.0 km · Kralupy nad Vltavou 16 km · Řepy 23 km · Louny 25 km · Bohnice 26 km · Stodůlky 26 km · Dejvice 26 km · Košíře 27 km

Czechia travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / E
230 V · 50 Hz
Prices
≈ 59% of US
price level, 2025
GDP per capita
$35,917
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
0.8
per 100k, 2023
Road deaths
5.9
per 100k/yr, 2019
Income group
High
World Bank
English
High
EF EPI 582
Religion
none 48%believers unaffiliated with a religious society 9%Roman Catholic 7%other believers belonging to a church or religious society 6%

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 Slaný (50.2305°, 14.0869°, elevation 282 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).