Río Grande weather in September

In September, Río Grande sees average daytime highs of 31°C and overnight lows near 25°C, with 76 mm of rain across 15.6 wet days and about 12.1 hours of daylight. It is the 2nd-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 35% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 24 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Río Grande's 11th-clearest and 10th-windiest month. For the whole year in context, see Río Grande's year-round climate.

Daytime high
31°
2nd warmest
Overnight low
25°
11th coldest
Rainfall
76 mm
15.6 wet days
Daylight
12 h 06 min
6:34 AM – 6:41 PM
Cloud cover
57%
11th clearest
Wind
12 km/h
10th windiest
Solar energy
6.16 kWh/m²
Travel score
4.0
out of 10

Río Grande is human settlement in the Dominican Republic.

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 31°C through the month.

A typical September day in Río Grande reaches about 31°C in the afternoon and slips back to 25°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 29°C and 32°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)
13125
23125
33125
43125
53125
63125
73125
83125
93125
103125
113125
123125
133125
143125
153125
163125
173125
183124
193124
203124
213124
223124
233124
243124
253124
263124
273124
283124
293124
303124

How September really feels in Río Grande

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.

Río Grande weather by month

How September compares with the rest of the year at a glance. September is the 2nd-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 21°6111.110.96.8
Feb27° / 21°448.811.37.0
Mar28° / 21°6210.511.96.7
Apr28° / 22°6212.212.45.9
May29° / 23°8415.912.94.7
Jun30° / 24°421013.24.7
Jul31° / 25°359.713.14.9
Aug31° / 25°4610.712.74.6
Sep31° / 25°7615.612.14.0
Oct30° / 24°831611.54.4
Nov28° / 23°8715.511.15.3
Dec27° / 22°6311.910.86.5

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 47%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15347
25347
35347
45347
55347
65347
75347
85347
95347
105347
115446
125446
135446
145446
155446
165446
175446
185446
195347
205347
215347
225347
235248
245347
255248
265248
275149
285149
295149
305149

Chance of precipitation in September

Any precipitation

Río Grande gets around 76 mm of rain over 15.6 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 51% and peaks near 56% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
146
247
347
447
547
647
748
848
949
1049
1150
1251
1351
1452
1552
1653
1754
1854
1955
2055
2156
2256
2356
2455
2555
2654
2753
2853
2952
3052

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 85% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
18317
28317
38317
48416
58416
68416
78416
88416
98515
108515
118515
128515
138614
148614
158614
168614
178614
188614
198614
208614
218614
228713
238713
248713
258713
268713
278713
288713
298713
308713

Wind in September

Winds average 12 km/h in September.

Across September, daily wind ranges from about 12 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512calm
2612calm
2712calm
2812calm
2912calm
3012calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 24 min at the start of September to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 36 minutes over September. Sunrise moves from 6:31 AM to 6:37 AM, and sunset from 6:55 PM to 6:28 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.46:316:55
212.46:316:54
312.46:316:53
412.36:326:52
512.36:326:51
612.36:326:50
712.36:326:49
812.36:326:48
912.26:336:47
1012.26:336:46
1112.26:336:45
1212.26:336:44
1312.26:336:44
1412.16:346:43
1512.16:346:42
1612.16:346:41
1712.16:346:40
1812.16:346:39
1912.16:356:38
2012.06:356:37
2112.06:356:36
2212.06:356:35
2312.06:366:34
2412.06:366:33
2511.96:366:32
2611.96:366:31
2711.96:366:30
2811.96:376:29
2911.96:376:29
3011.86:376:28

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.16 kWh/m².

For context, solar energy here swings from a low near 4.15 kWh/m² to a high of 6.9 kWh/m² in June across the year — September's 6.16 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.4Intense
26.4Intense
36.4Intense
46.3Intense
56.3Intense
66.3Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.3Intense
126.2Intense
136.2Intense
146.2Intense
156.2Intense
166.2Intense
176.1Intense
186.1Intense
196.1Intense
206.0Intense
216.0Intense
226.0Intense
236.0Bright
246.0Bright
255.9Bright
265.9Bright
275.9Bright
285.8Bright
295.8Bright
305.8Bright
Planning a trip in September

Hazard calendar for Río Grande

In seasonPeak

In September, Río Grande sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Río Grande sits in the Atlantic hurricane belt; the season peaks August–October.

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

Is September a good time to visit Río Grande?

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

4.0
Sightseeing
12th-best month of the year
5.9
Beach & pool
12th-best month of the year

September is a reasonable time to visit Río Grande for sightseeing.

What to pack for Río Grande in September

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

In September, Río Grande sees daytime highs around 31°C and nights near 25°C. Pack light clothes, rain gear and sun protection. About 16 days see rain.

light clothesrain gearsun protection

Sea temperature near Río Grande in September

The nearest coast averages about 29°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 26 km away) is warmest in September at about 29°C and coldest in February near 26°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan26Warm
Feb26Warm
Mar26Warm
Apr26Warm
May27Warm
Jun28Warm
Jul28Tropical
Aug28Tropical
Sep29Tropical
Oct29Tropical
Nov28Tropical
Dec27Warm

UV index in Río Grande 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 Río Grande peaks around March 22 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 7 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highHighMar 22UV 12Dec 15UV 7
UV index (midday)Level
Jan8Very high
Feb10Very high
Mar12Extreme
Apr12Extreme
May11Extreme
Jun12Extreme
Jul12Extreme
Aug11Extreme
Sep11Extreme
Oct10Very high
Nov7Very high
Dec7High

Air quality in Río Grande 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 Río Grande is worst in June — around 30 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (February, 16 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateJun 2030 µg/m³Feb 2016 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb16Moderate
Mar16Moderate
Apr18Moderate
May23Moderate
Jun30Moderate
Jul28Moderate
Aug25Moderate
Sep26Moderate
Oct27Moderate
Nov20Moderate
Dec17Moderate
Location & terrain

Where is Río Grande?

Río Grande sits at 19.7°N, 70.8°W, 397 m above sea level, in Dominican Republic. The nearest listed city is Villa Bisonó, 16 km away.

EsperanzaSantiago de los CaballerosTamborilSosuaMao

Topography around Río Grande

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

Within 3 km, the terrain around Río Grande has significant variations in elevation — a maximum elevation change of 453 m around an average of 344 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,235 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,073 m.

The land around Río Grande is covered by trees (88%) within 3 km, trees (78%) within 16 km, and trees (47%) and water (30%) within 80 km.

3 km
453 m
16 km
1,235 m
80 km
3,073 m
treesshrubsgrasslandcroplandartificial surfaceswater
September weather nearby: Villa Bisonó 16 km · Puerto Plata 16 km · Monte Llano 19 km · Esperanza 25 km · Santiago de los Caballeros 25 km · Tamboril 26 km · Sosua 28 km · Mao 35 km

Dominican Republic travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B / C
120 V · 60 Hz
Prices
≈ 39% of US
price level, 2025
GDP per capita
$11,059
2025
Happiness
6.1 / 10
World Happiness, 2025
Safe drinking water
45%
of population, 2024
Homicide rate
10.9
per 100k, 2023
Road deaths
64.6
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Moderate
EF EPI 503

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 Río Grande (19.6667°, -70.7667°, elevation 397 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).