Petatlán weather in September

In September, Petatlán sees average daytime highs of 29°C and overnight lows near 24°C, with 338 mm of rain across 23.5 wet days and about 12.1 hours of daylight. It is the 9th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 4% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 18 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Petatlán's 12th-clearest and 6th-windiest month. For the whole year in context, see Petatlán's year-round climate.

Daytime high
29°
9th warmest
Overnight low
24°
9th coldest
Rainfall
338 mm
23.5 wet days
Daylight
12 h 06 min
6:36 AM – 6:42 PM
Cloud cover
84%
12th clearest
Wind
6 km/h
6th windiest
Solar energy
4.82 kWh/m²
Travel score
3.5
out of 10

Petatlán is municipal seat of Petatlán, State of Guerrero, Mexico.

Density
10/km²
people per km²
Founded
1550

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical September day in Petatlán reaches about 29°C in the afternoon and slips back to 24°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 30°C. Set against its neighbours, September runs on par with August and on par with October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12924
22924
32924
42924
52924
62924
72924
82924
92924
102924
112924
122924
132924
142924
152924
162924
172924
182924
192924
202924
212924
222924
232924
242924
252924
262924
272924
282924
292924
302924

How September really feels in Petatlán

Once humidity and wind are folded in, September averages 30 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
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Petatlán weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 20°9111.17.3
Feb29° / 20°50.411.47.3
Mar29° / 20°60.411.97.1
Apr30° / 21°0012.46.5
May31° / 23°243.712.85.6
Jun30° / 24°22018.1134.0
Jul30° / 24°19819.112.93.8
Aug30° / 24°2562112.63.7
Sep29° / 24°33823.512.13.5
Oct29° / 23°21220.311.64.1
Nov29° / 22°355.911.26.2
Dec29° / 21°81.7117.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 4% of the time in September, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 10% of September, with mostly cloudy or overcast conditions the remaining 86%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
11387
21387
31387
41387
51288
61288
71387
81387
91288
101288
111387
121387
131387
141387
151387
161486
171486
181486
191486
201387
211486
221486
231486
241486
251585
261684
271684
281882
291882
301981

Chance of precipitation in September

Any precipitation

Petatlán gets around 338 mm of rain over 23.5 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 78% and peaks near 79% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
176
277
377
478
578
678
778
878
978
1078
1178
1278
1378
1478
1578
1678
1778
1878
1978
2079
2179
2279
2379
2479
2579
2679
2778
2878
2978
3078

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 80% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
18020
28020
38119
48119
58218
68218
78218
88218
98218
108218
118218
128119
138119
148119
158020
168020
178020
187921
197921
207921
217921
227822
237822
247822
257822
267822
277822
287723
297723
307723

Wind in September

Winds average 6 km/h in September.

Across September, daily wind ranges from about 6 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 18 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 24 minutes over September. Sunrise moves from 6:34 AM to 6:39 AM, and sunset from 6:55 PM to 6:30 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.36:346:55
212.36:356:54
312.36:356:54
412.36:356:53
512.36:356:52
612.36:356:51
712.26:356:50
812.26:356:49
912.26:366:48
1012.26:366:48
1112.26:366:47
1212.26:366:46
1312.16:366:45
1412.16:366:44
1512.16:366:43
1612.16:366:42
1712.16:376:41
1812.16:376:41
1912.06:376:40
2012.06:376:39
2112.06:376:38
2212.06:376:37
2312.06:376:36
2412.06:386:35
2511.96:386:34
2611.96:386:34
2711.96:386:33
2811.96:386:32
2911.96:386:31
3011.96:396:30

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.82 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 4.82 kWh/m² to a high of 7.41 kWh/m² in April across the year — September's 4.82 kWh/m² sits near the bottom.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
144.9Bright
154.9Bright
164.8Bright
174.8Bright
184.8Bright
194.8Bright
204.8Bright
214.8Bright
224.7Bright
234.7Bright
244.7Bright
254.7Bright
264.7Bright
274.7Bright
284.7Bright
294.7Bright
304.7Bright
Planning a trip in September

Hazard calendar for Petatlán

In seasonPeak

In September, Petatlán sits inside its pacific hurricane and monsoon season. The full year is below, with each hazard's peak months called out.

Petatlán sits in the eastern Pacific hurricane zone; the season peaks August–September.

Petatlán's monsoon runs June–October, when most of the year's rain falls.

Pacific hurricane
Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Petatlán?

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

3.5
Sightseeing
12th-best month of the year
4.6
Beach & pool
12th-best month of the year

September is a weaker month for outdoor sightseeing in Petatlán.

What to pack for Petatlán in September

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

In September, Petatlán sees daytime highs around 29°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 24 days see rain.

light clothesrain gearsun protection

Sea temperature near Petatlán in September

The nearest coast averages about 30°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 21 km away) is warmest in August at about 30°C and coldest in March near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Tropical
Feb28Warm
Mar27Warm
Apr27Warm
May28Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct30Tropical
Nov29Tropical
Dec29Tropical

UV index in Petatlán in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Petatlán peaks around March 23 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 13 at about 7 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highMar 23UV 13Dec 13UV 7
UV index (midday)Level
Jan9Very high
Feb11Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug11Extreme
Sep11Extreme
Oct8Very high
Nov8Very high
Dec7High

Air quality in Petatlán 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 Petatlán is worst in May — around 28 µg/m³ PM2.5 (moderate), about 8.1× the cleanest month (February, 3 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMay 1625 µg/m³Feb 154 µg/m³
PM2.5 (µg/m³)Level
Jan5Good
Feb3Good
Mar5Good
Apr12Good
May28Moderate
Jun11Good
Jul13Moderate
Aug9Good
Sep7Good
Oct6Good
Nov5Good
Dec5Good
Location & terrain

Where is Petatlán?

Petatlán sits at 17.5°N, 101.3°W, 39 m above sea level, in Mexico. The nearest listed city is Zihuatanejo, 32 km away.

Topography around Petatlán

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

Within 3 km, the terrain around Petatlán has only modest variations in elevation — a maximum elevation change of 155 m around an average of 39 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,493 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,839 m.

The land around Petatlán is covered by trees (43%) and grassland (26%) within 3 km, trees (54%) within 16 km, and trees (56%) and water (33%) within 80 km.

3 km
155 m
16 km
1,493 m
80 km
2,839 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
September weather nearby: Zihuatanejo 32 km · Técpan de Galeana 76 km · Atoyac de Álvarez 96 km · Ciudad Lázaro Cárdenas 109 km · Ciudad Altamirano 111 km · Las Guacamayas 113 km · La Orilla 114 km · Huetamo de Núñez 127 km

Mexico travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B
120 / 127 V · 60 Hz
Prices
≈ 54% of US
price level, 2025
GDP per capita
$13,889
2025
Happiness
7.0 / 10
World Happiness, 2025
Safe drinking water
43%
of population, 2024
Homicide rate
24.9
per 100k, 2023
Road deaths
12.8
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 440
Religion
Catholic 78%no religion 11%other Evangelical Churches 8%Jehovah Witness 1%

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 Petatlán (17.5377°, -101.268°, elevation 39 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).