5-day weather forecast Rio de Janeiro 18-05-2026

Weather forecast Rio de Janeiro Monday, May 18 18.05.2026: patchy rain possible, temperature from 21 °C to 25 °C.

Precipitation probability 100%. Wind up to 5.89 m/s (gusts 9.42 m/s). Air humidity 77–95%, atmospheric pressure 760–763 mm Hg, UV index up to 3.7.

Sunrise 06:20
Sunset 17:18

Waxing Crescent2% illuminated
Moonrise 08:19 · Moonset 19:03

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Table

← Sun, May 17

Mon, May 18, 2026

Tue, May 19 →

Forecast from 21 °C to 25 °C and precipitation

Temperature & Precipitation
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Temperature (°C)	21	21	21	21	21	21	21	22	23	23	24	24	25	25	24	24	24	24	23	23	23	23	23	23
Precipitation (mm/hr)	0.39	0.28	0	0	0	0	0	0	0	0.01	0.02	0	0.07	0.06	0.01	0.03	0.02	0.13	0.24	0.01	0.08	0.06	0.02	0.02

Cloud cover and precipitation probability

Cloud cover & Rain chance
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Cloud cover (%)	85	61	46	33	59	48	39	35	55	52	52	53	95	100	52	80	72	86	84	87	72	58	77	85
Rain chance (%)	100	100	0	0	0	0	0	0	0	89	71	0	100	100	74	62	77	100	100	70	100	100	67	77

Wind speed and direction

Wind & Wind gust
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Wind (m/s)	3.31	2.89	5.89	3.31	1.31	1.39	1.61	1.19	1.11	0.89	1.81	2.31	3.89	3.31	0.61	1.19	2.5	1.61	1.19	0.89	1.31	1.19	0.81	0.61
Wind gust (m/s)	4.69	4.31	9.42	5.44	2.31	2.53	2.83	2.03	1.61	1.25	2.53	2.92	4.86	4.06	0.81	1.78	4.08	2.78	2.11	1.58	2.22	1.97	1.28	0.92
Wind direction (°)	W 276°	NNW 345°	NNE 20°	NNW 345°	NW 315°	WNW 282°	WNW 282°	NW 305°	NW 316°	W 276°	SW 232°	WSW 237°	SW 234°	WSW 237°	SW 216°	NNE 13°	NE 35°	NNE 16°	NNW 331°	N 353°	WNW 297°	W 269°	WSW 241°	SW 222°

Air humidity

Humidity
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Humidity (%)	95	95	95	93	92	92	91	89	86	83	83	77	77	78	80	82	82	83	83	85	86	88	90	90

Atmospheric pressure

Pressure
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
Pressure (mm Hg)	763	762	760	760	760	760	761	761	762	763	763	763	763	762	761	761	761	761	761	761	762	762	762	762

Ultraviolet index

UV Index
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
UV Index	0	0	0	0	0	0	0	0.1	0.9	1.7	1.7	3.2	3.7	3.2	1.7	0.6	0.2	0	0	0	0	0	0	0

Air quality & pollen

Air quality
Time	00:00	01:00	02:00	03:00	04:00	05:00	06:00	07:00	08:00	09:00	10:00	11:00	12:00	13:00	14:00	15:00	16:00	17:00	18:00	19:00	20:00	21:00	22:00	23:00
PM2.5 (µg/m³)	15.1	14.5	14.1	14.5	17	21.4	22.7	24.4	24.5	22.7	20.1	20.1	20.1	19.8	20.8	20	13.9	12	9.1	10.5	7.4	5.1	6.4	6.9
PM10 (µg/m³)	15.2	14.6	14.2	14.7	17.1	21.9	23.4	25.2	26.3	25.7	22.8	24.1	24.8	24.5	24.9	23.9	17.1	15	11.4	13.1	9.2	6.4	7.9	8.6
Ozone (O₃) (µg/m³)	20	15	9	13	33	61	90	120	150	165	155	130	105	84	64	49	42	40	39	37	36	36	36	38
NO₂ (µg/m³)	23.2	23.3	24.6	26.2	28.7	31.5	31.8	27.2	20	14.9	13.2	13.5	16	22.6	31.4	36.8	35.5	30.7	26.5	24.3	22.6	20.9	18.7	16.6
SO₂ (µg/m³)	5.8	5.8	6	6.6	7.8	9.4	10.5	10.8	10.7	10.5	10.3	9.9	9.6	9.4	9.2	9.1	9	9	8.8	8.3	7.6	7.1	6.8	6.6
CO (µg/m³)	502.9	472.9	456.9	454.9	477.9	513.9	521.9	476.9	403.9	338.9	290.9	250.9	221.9	209.9	208.9	204.9	188.9	169.9	153.9	146.9	144.9	139.9	127.9	112.9

← Sun, May 17

Mon, May 18, 2026

Tue, May 19 →

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Data Sources & Methodology

Our weather forecasts are powered by a professional weather data provider that aggregates data from national weather services, satellite observations, radar networks, and over 80,000 weather stations worldwide. Forecast data is updated multiple times daily. We convert raw data into clear summaries — wind speed in m/s, pressure in mmHg — so you can plan your day with confidence.

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