Sīāhkal weather in December

In December, Sīāhkal sees average daytime highs of 14°C and overnight lows near 6°C, with 125 mm of precipitation across 11.3 wet days and about 9.5 hours of daylight. It is the 10th-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 14°C through the month. The sky is clear or mostly clear about 37% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 36 min at the start of December to 9 h 30 min by month's end. Set against the rest of the year, December is Sīāhkal's 4th-clearest and 2nd-windiest month. For the whole year in context, see Sīāhkal's year-round climate.

Daytime high
14°
10th warmest
Overnight low
3rd coldest
Precipitation
125 mm
11.3 wet days
Daylight
9 h 30 min
7:23 AM – 4:50 PM
Cloud cover
57%
4th clearest
Wind
7 km/h
2nd windiest
Solar energy
2.07 kWh/m²
Travel score
3.8
out of 10

Sīāhkal is city in Gilan Province, Iran.

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 14°C through the month.

A typical December day in Sīāhkal reaches about 14°C in the afternoon and slips back to 6°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 9°C and 19°C. Set against its neighbours, December runs about 4°C cooler than November and about 2°C warmer than January.

-5°10°15°20°151015202531
Avg high (°C)Avg low (°C)
1157
2157
3147
4147
5147
6146
7146
8146
9146
10146
11146
12146
13146
14136
15136
16135
17135
18135
19135
20135
21135
22135
23135
24135
25135
26135
27135
28135
29135
30135
31134

How December really feels in Sīāhkal

Once humidity and wind are folded in, December averages 0 days that feel above 32°C and 0 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
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Sīāhkal weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan12° / 11611.21.69.73.0
Feb12° / 11711.62.210.63.0
Mar15° / 10913.10.411.74.3
Apr19° / 11°7710.6012.95.9
May24° / 15°478.50147.0
Jun28° / 19°667.7014.56.7
Jul30° / 22°768.7014.35.4
Aug30° / 22°9610.6013.45.2
Sep26° / 19°16913.8012.36.0
Oct22° / 14°18814.60116.0
Nov17° / 10°17813.20.3105.0
Dec14° / 12511.30.69.53.8

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 11% of December, with mostly cloudy or overcast conditions the remaining 52%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24357
34357
44357
54357
64258
74258
84258
94357
104357
114456
124555
134555
144753
154753
164852
174951
185050
195149
205149
215248
225248
235347
245347
255347
265446
275347
285347
295248
305248
315248

Chance of precipitation in December

Any precipitationSnow

Sīāhkal gets around 125 mm of rain and snow over 11.3 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 37% and peaks near 45% on the wettest days, and about 1 day brings snow. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)Snow chance (%)
1451
2451
3441
4441
5431
6432
7432
8422
9422
10412
11402
12393
13393
14383
15373
16363
17363
18353
19353
20343
21333
22333
23322
24312
25312
26302
27302
28302
29302
30302
31303

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
3991
4991
5991
6991
7991
8991
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 7 km/h in December.

Across December, daily wind ranges from about 7 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 36 min at the start of December to 9 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 7:11 AM to 7:29 AM, and sunset from 4:49 PM to 4:58 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.67:114:49
29.67:124:49
39.67:134:49
49.67:144:49
59.67:154:49
69.67:164:49
79.57:164:49
89.57:174:49
99.57:184:49
109.57:194:49
119.57:204:49
129.57:204:49
139.57:214:50
149.57:224:50
159.57:224:50
169.57:234:50
179.57:244:51
189.47:244:51
199.47:254:51
209.47:254:52
219.47:264:52
229.47:264:53
239.47:274:53
249.47:274:54
259.47:274:54
269.47:284:55
279.57:284:55
289.57:294:56
299.57:294:57
309.57:294:57
319.57:294:58

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.07 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.07 kWh/m² to a high of 6.29 kWh/m² in June across the year — December's 2.07 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.1Moderate
22.0Moderate
32.0Moderate
42.0Moderate
52.0Moderate
62.0Moderate
72.0Moderate
82.0Moderate
92.0Moderate
102.0Moderate
112.0Moderate
122.0Moderate
132.0Moderate
142.0Moderate
152.0Moderate
162.0Moderate
172.1Moderate
182.1Moderate
192.1Moderate
202.1Moderate
212.1Moderate
222.1Moderate
232.1Moderate
242.2Moderate
252.2Moderate
262.2Moderate
272.2Moderate
282.2Moderate
292.2Moderate
302.2Moderate
312.2Moderate
Planning a trip in December

Is December a good time to visit Sīāhkal?

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

3.8
Sightseeing
10th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Sīāhkal.

What to pack for Sīāhkal in December

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

In December, Sīāhkal sees daytime highs around 14°C and nights near 6°C. Worth packing: a warm layer and rain gear. About 11 days see rain.

a warm layerrain gear

Sea temperature near Sīāhkal in December

The nearest coast averages about 15°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 33 km away) is warmest in August at about 28°C and coldest in February near 10°C.

It's comfortable for a long swim from May 24 to Nov 4 — about 5.4 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan12Bracing
Feb10Bracing
Mar11Bracing
Apr13Bracing
May19Cool
Jun24Warm
Jul27Warm
Aug28Warm
Sep26Warm
Oct23Refreshing
Nov19Cool
Dec15Bracing

UV index in Sīāhkal 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 Sīāhkal peaks around July 17 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 11 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJul 17UV 9Jan 11UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr6High
May8Very high
Jun8Very high
Jul9Very high
Aug8Very high
Sep6High
Oct5Moderate
Nov3Moderate
Dec2Moderate

Air quality in Sīāhkal 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 Sīāhkal is worst in March — around 27 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (July, 14 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1826 µg/m³Jul 1315 µg/m³
PM2.5 (µg/m³)Level
Jan21Moderate
Feb21Moderate
Mar27Moderate
Apr23Moderate
May21Moderate
Jun17Moderate
Jul14Moderate
Aug20Moderate
Sep25Moderate
Oct23Moderate
Nov21Moderate
Dec20Moderate
Location & terrain

Where is Sīāhkal?

Sīāhkal sits at 37.2°N, 49.9°E, 47 m above sea level, in Iran. The nearest listed city is Lāhījān, 13 km away.

Topography around Sīāhkal

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

Within 3 km, the terrain around Sīāhkal has only modest variations in elevation — a maximum elevation change of 148 m around an average of 44 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,255 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,710 m.

The land around Sīāhkal is covered by trees (40%) and cropland (39%) within 3 km, trees (56%) and cropland (34%) within 16 km, and water (35%), trees (25%) and grassland (25%) within 80 km.

3 km
148 m
16 km
1,255 m
80 km
3,710 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
December weather nearby: Lāhījān 13 km · Āstāneh-ye Ashrafīyeh 14 km · Langarūd 25 km · Rasht 29 km · Amlash 29 km · Khomām 32 km · Rūdsar 37 km · Fūman 50 km

Iran travel facts

Travel advisory
Level 4
Do Not Travel
Power plugs
Type C / F
220 V · 50 Hz
Prices
≈ 352% of US
price level, 2025
GDP per capita
$3,924
2025
Happiness
5.2 / 10
World Happiness, 2025
Safe drinking water
94%
of population, 2024
Homicide rate
2.4
per 100k, 2014
Road deaths
21.5
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 492
Religion
Muslim 99%Christian 1%Baha'i 0%agnostic 0%

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 Sīāhkal (37.1533°, 49.8714°, elevation 47 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).