Byblos weather in September

In September, Byblos sees average daytime highs of 27°C and overnight lows near 17°C, with 6 mm of rain across 1.6 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 25°C by the end. The sky is clear or mostly clear about 94% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 12 h 42 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Byblos's 4th-clearest and 10th-windiest month. For the whole year in context, see Byblos's year-round climate.

Daytime high
27°
3rd warmest
Overnight low
17°
10th coldest
Rainfall
6 mm
1.6 wet days
Daylight
12 h 12 min
5:25 AM – 5:38 PM
Cloud cover
12%
4th clearest
Wind
7 km/h
10th windiest
Solar energy
6.03 kWh/m²
Travel score
8.8
out of 10

Byblos is Mediterranean city in the Mount Lebanon Governorate, Lebanon, a main Canaanite-Phoenician city.

Density
4,157/km²
people per km²
Founded
~8000 BCE

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 25°C by the end.

A typical September day in Byblos reaches about 27°C in the afternoon and slips back to 17°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 29°C. Set against its neighbours, September runs about 2°C cooler than August and about 3°C warmer than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12818
22818
32818
42718
52718
62718
72718
82718
92718
102718
112718
122718
132718
142718
152717
162717
172617
182617
192617
202617
212617
222617
232617
242617
252617
262616
272516
282516
292516
302516

Byblos weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan11° / 12613.73.6102.5
Feb11° / 121123.410.72.8
Mar14° / 9910.91.411.74.2
Apr18° / 497.10.212.86.3
May22° / 13°244.5013.88.1
Jun25° / 16°30.6014.29.3
Jul28° / 19°00.10148.8
Aug28° / 19°10.3013.38.3
Sep27° / 17°61.6012.28.8
Oct23° / 14°305.8011.18.1
Nov18° / 6980.310.26.2
Dec13° / 10911.41.49.83.7

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 94% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 5% of September, with mostly cloudy or overcast conditions the remaining 1%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
11000
21000
31000
41000
51000
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
18991
19991
20991
21991
22982
23982
24982
25982
26973
27973
28973
29964
30964

Chance of precipitation in September

Any precipitation

Byblos gets around 6 mm of rain over 1.6 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 5% and peaks near 10% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%151015202530
Rain chance (%)
12
22
32
42
52
63
73
83
93
103
113
124
134
144
154
164
175
185
196
206
217
227
237
248
258
269
279
289
2910
3010

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 47% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
11140418
21241397
31342387
41443366
51545356
61646335
71846324
81947304
92048293
102149283
112249272
122349262
132450251
142550241
152650231
162750221
172850211
182950201
193051190
203151180
213350170
223450160
233649150
243849140
254048120
264247110
274446100
28464590
29484480
30504380

Wind in September

Winds average 7 km/h in September.

Across September, 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.

0246810151015202530
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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 42 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 60 minutes over September. Sunrise moves from 5:15 AM to 5:36 AM, and sunset from 6:00 PM to 5:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:156:00
212.75:155:58
312.75:165:57
412.65:175:55
512.65:185:54
612.65:185:52
712.55:195:51
812.55:205:50
912.55:205:48
1012.45:215:47
1112.45:225:45
1212.45:235:44
1312.35:235:42
1412.35:245:41
1512.25:255:39
1612.25:255:38
1712.25:265:37
1812.15:275:35
1912.15:285:34
2012.15:285:32
2112.05:295:31
2212.05:305:29
2312.05:315:28
2411.95:315:26
2511.95:325:25
2611.85:335:23
2711.85:335:22
2811.85:345:21
2911.75:355:19
3011.75:365:18

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.03 kWh/m².

For context, solar energy here swings from a low near 2.6 kWh/m² to a high of 8 kWh/m² in June across the year — September's 6.03 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.7Intense
26.7Intense
36.6Intense
46.6Intense
56.5Intense
66.5Intense
76.4Intense
86.4Intense
96.3Intense
106.3Intense
116.3Intense
126.2Intense
136.2Intense
146.1Intense
156.1Intense
166.0Intense
176.0Bright
185.9Bright
195.9Bright
205.8Bright
215.8Bright
225.7Bright
235.7Bright
245.6Bright
255.6Bright
265.5Bright
275.5Bright
285.4Bright
295.4Bright
305.3Bright
Planning a trip in September

Hazard calendar for Byblos

In seasonPeak

None of Byblos's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Byblos's rainy season runs November–March, when most of the year's rain falls.

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

Is September a good time to visit Byblos?

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

8.8
Sightseeing
2nd-best month of the year
8.6
Beach & pool
3rd-best month of the year

September is one of the better times to visit Byblos for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Byblos in September

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

In September, Byblos sees daytime highs around 27°C and nights near 17°C. Pack sun protection. Worth having: light clothes.

sun protectionlight clothes

Sea temperature near Byblos in September

The nearest coast averages about 28°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 28°C and coldest in February near 17°C.

It's comfortable for a long swim from May 3 to Dec 23 — about 7.7 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan19Cool
Feb17Cool
Mar17Cool
Apr19Cool
May21Refreshing
Jun25Warm
Jul27Warm
Aug28Tropical
Sep28Warm
Oct26Warm
Nov23Refreshing
Dec21Refreshing

UV index in Byblos in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Byblos peaks around June 21 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near January 11 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 21UV 10Jan 11UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun11Extreme
Jul10Very high
Aug10Very high
Sep8Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Byblos in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Byblos is worst in November — around 58 µg/m³ PM2.5 (unhealthy), about 1.9× the cleanest month (July, 31 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecPoorPoorModeratePoorUnhealthyNov 2258 µg/m³Jul 2231 µg/m³
PM2.5 (µg/m³)Level
Jan52Poor
Feb57Unhealthy
Mar52Poor
Apr54Poor
May44Poor
Jun35Poor
Jul31Moderate
Aug31Moderate
Sep41Poor
Oct51Poor
Nov58Unhealthy
Dec57Unhealthy
Location & terrain

Where is Byblos?

Byblos sits at 34.1°N, 35.6°E, 33 m above sea level, in Lebanon. The nearest listed city is Jounieh, 16 km away.

JouniehBeirutRa’s BayrūtAleyBsharriChmistârZahleTripoli

Topography around Byblos

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

Within 3 km, the terrain around Byblos has significant variations in elevation — a maximum elevation change of 494 m around an average of 90 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,768 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,068 m.

The land around Byblos is covered by water (41%), trees (29%) and artificial surfaces (21%) within 3 km, water (47%) and trees (37%) within 16 km, and grassland (35%) and water (34%) within 80 km.

3 km
494 m
16 km
1,768 m
80 km
3,068 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Jounieh 16 km · Beirut 29 km · Ra’s Bayrūt 29 km · Aley 35 km · Bsharri 36 km · Chmistâr 38 km · Zahle 38 km · Tripoli 39 km

Lebanon travel facts

Travel advisory
Level 4
Do Not Travel
Power plugs
Type A / B / C / D / G
220 V · 50 Hz
Prices
≈ 38% of US
price level, 2024
GDP per capita
$4,473
2024
Happiness
3.7 / 10
World Happiness, 2025
Safe drinking water
48%
of population, 2024
Homicide rate
2.2
per 100k, 2020
Road deaths
16.4
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Low
EF EPI 477
Religion
Muslim 68%Christian 32%Druze 5%

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 Byblos (34.1211°, 35.6481°, elevation 33 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).