Sīāhkal weather in May

In May, Sīāhkal sees average daytime highs of 24°C and overnight lows near 15°C, with 47 mm of rain across 8.5 wet days and about 14 hours of daylight. It is the 5th-warmest and 12th-wettest month of the year here.

Highs climb over the month, from about 21°C in the first days to 26°C by the end. The sky is clear or mostly clear about 35% of the time in May, and the air most often feels comfortable.

Daylight stretches from about 13 h 30 min at the start of May to 14 h 18 min by month's end. Set against the rest of the year, May is Sīāhkal's 4th-clearest and 11th-windiest month. For the whole year in context, see Sīāhkal's year-round climate.

Daytime high
24°
5th warmest
Overnight low
15°
8th coldest
Rainfall
47 mm
8.5 wet days
Daylight
14 hours
5:07 AM – 7:06 PM
Cloud cover
57%
4th clearest
Wind
6 km/h
11th windiest
Solar energy
5.95 kWh/m²
Travel score
7.0
out of 10

Sīāhkal is city in Gilan Province, Iran.

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 21°C in the first days to 26°C by the end.

A typical May day in Sīāhkal reaches about 24°C in the afternoon and slips back to 15°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 28°C. Set against its neighbours, May runs about 5°C warmer than April and about 4°C cooler than June.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12113
22113
32113
42113
52213
62214
72214
82214
92214
102314
112315
122315
132315
142315
152415
162415
172415
182416
192416
202416
212516
222516
232516
242516
252517
262517
272617
282617
292617
302617
312617

How May really feels in Sīāhkal

Once humidity and wind are folded in, May 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

May 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 May compares with the rest of the year at a glance. May is the 5th-warmest and 12th-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 May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 15% of May, with mostly cloudy or overcast conditions the remaining 50%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14060
24159
34258
44258
54456
64456
74456
84555
94456
104456
114555
124555
134654
144654
154654
164654
174951
184951
194951
205149
215248
225446
235545
245644
255743
265842
275941
286040
296139
306139
316139

Chance of precipitation in May

Any precipitation

Sīāhkal gets around 47 mm of rain over 8.5 wet days in May, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 29% and peaks near 35% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
135
234
333
432
532
631
731
830
930
1030
1130
1230
1330
1430
1529
1629
1729
1829
1928
2028
2127
2227
2326
2426
2525
2625
2725
2825
2925
3025
3125

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the comfortable band about 38% of days. Sticky, muggy-or-worse air turns up on roughly 13% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
140431610
237441810
335451910
432462110
529462320
627472520
724472620
822472830
920473030
1018473240
1116473340
1214463550
1313453650
1412453860
1511443970
169434080
178424190
1884142100
1973942110
2063843131
2153643151
2253443171
2343243191
2443043221
2532943241
2632743262
2732543282
2822342302
2922142322
3022042342
3121842353

Wind in May

Winds average 6 km/h in May.

Across May, daily wind ranges from about 6 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
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 30 min at the start of May to 14 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 48 minutes over May. Sunrise moves from 5:23 AM to 4:58 AM, and sunset from 6:53 PM to 7:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.55:236:53
213.55:216:54
313.65:206:55
413.65:196:56
513.65:186:57
613.75:176:57
713.75:166:58
813.75:156:59
913.85:147:00
1013.85:137:01
1113.85:127:02
1213.95:117:03
1313.95:107:04
1413.95:097:05
1514.05:087:05
1614.05:077:06
1714.05:067:07
1814.05:067:08
1914.15:057:09
2014.15:047:10
2114.15:037:10
2214.15:037:11
2314.25:027:12
2414.25:017:13
2514.25:017:14
2614.25:007:14
2714.35:007:15
2814.34:597:16
2914.34:597:17
3014.34:587:17
3114.34:587:18

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.95 kWh/m².

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 — May's 5.95 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.6Bright
55.6Bright
65.6Bright
75.7Bright
85.7Bright
95.7Bright
105.8Bright
115.8Bright
125.8Bright
135.8Bright
145.9Bright
155.9Bright
165.9Bright
175.9Bright
186.0Bright
196.0Intense
206.0Intense
216.0Intense
226.1Intense
236.1Intense
246.1Intense
256.2Intense
266.2Intense
276.2Intense
286.2Intense
296.3Intense
306.3Intense
316.3Intense
Planning a trip in May

Is May a good time to visit Sīāhkal?

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

7.0
Sightseeing
1st-best month of the year
5.6
Beach & pool
5th-best month of the year

May is one of the better times to visit Sīāhkal for general sightseeing.

What to pack for Sīāhkal in May

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

In May, Sīāhkal sees daytime highs around 24°C and nights near 15°C. Worth packing: light clothes, rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

Sea temperature near Sīāhkal in May

The nearest coast averages about 19°C in May — 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 May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 — enough to warrant sun protection. 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 May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May 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
May 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).