Parnaíba climate

Name: Parnaíba
Address: BR

Parnaíba is warmest in September, with average highs of 34 °C, and coldest in March, when nights average 25 °C. March is the wettest month (269 mm) and September the driest (1.5 mm). Figures are 1991–2020 climate normals.

Across a full year Parnaíba averages 1,092 mm of rain and 365 days above 25 °C.

Brazil · population 170,491 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month September 34 °C
Coldest month March 25 °C
Driest month September 2 mm
Wettest month March 269 mm
Least cloud September 22 % cloud
Hottest on record October 37 °C
Coldest on record August 22 °C
Warmest sea May 29 °C

What to expectParnaíba through the year

Parnaíba changes little through the year. Average daily highs stay between 29 and 34 °C, so no month stands out as a season in the way it would further from the equator.

Counted across a normal year, 365 days a year reach 25 °C, 250 of them reach 30 °C. The warmest reading in the 1991–2020 record is 37 °C, in October.

Rain is strongly seasonal. March averages 269 mm against 2 mm in September — 179 times as much. Planning around the dry months matters more here than planning around temperature.

The sea off Parnaíba is warmest in May at 29 °C and coldest in September at 27 °C. Sea temperature lags the air by a month or two, which is why late summer swims warmer than early summer at the same air temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	30.1 °C	130 mm	72 %
February	29.4 °C	173 mm	76 %
March	29.1 °C	269 mm	80 %
April	29.2 °C	267 mm	79 %
May	30.0 °C	149 mm	61 %
June	31.0 °C	33 mm	40 %
July	32.1 °C	19 mm	33 %
August	33.4 °C	3 mm	25 %
September	33.8 °C	2 mm	22 %
October	33.5 °C	6 mm	31 %
November	33.0 °C	8 mm	45 %
December	32.0 °C	34 mm	55 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	30.1 °C	24.9 °C	27.0 °C	35.5 °C	22.8 °C	31	15
February	29.4 °C	24.6 °C	26.6 °C	35.3 °C	22.6 °C	28	7
March	29.1 °C	24.5 °C	26.4 °C	34.4 °C	22.9 °C	31	6
April	29.2 °C	24.6 °C	26.4 °C	32.9 °C	22.7 °C	30	7
May	30.0 °C	24.8 °C	26.9 °C	33.5 °C	22.8 °C	31	14
June	31.0 °C	24.8 °C	27.4 °C	34.5 °C	22.2 °C	30	23
July	32.1 °C	24.7 °C	27.7 °C	36.1 °C	22.3 °C	31	29
August	33.4 °C	24.8 °C	28.1 °C	36.3 °C	21.9 °C	31	31
September	33.8 °C	24.9 °C	28.1 °C	37.2 °C	23.1 °C	30	30
October	33.5 °C	25.2 °C	28.2 °C	37.3 °C	23.6 °C	31	31
November	33.0 °C	25.4 °C	28.2 °C	36.1 °C	23.4 °C	30	30
December	32.0 °C	25.5 °C	28.0 °C	35.5 °C	23.0 °C	31	28

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind	Sea temp
January	130 mm	20	12 h/day	72 %	80 %	20 km/h	28.2 °C
February	173 mm	23	12 h/day	76 %	83 %	19 km/h	28.4 °C
March	269 mm	28	12 h/day	80 %	85 %	17 km/h	28.5 °C
April	267 mm	26	12 h/day	79 %	85 %	16 km/h	28.8 °C
May	149 mm	18	12 h/day	61 %	82 %	16 km/h	28.9 °C
June	33 mm	7	12 h/day	40 %	75 %	18 km/h	28.5 °C
July	19 mm	3	12 h/day	33 %	69 %	19 km/h	27.8 °C
August	3 mm	1	12 h/day	25 %	66 %	23 km/h	27.3 °C
September	2 mm	0	12 h/day	22 %	66 %	26 km/h	27.0 °C
October	6 mm	1	12 h/day	31 %	68 %	27 km/h	27.2 °C
November	8 mm	2	12 h/day	45 %	69 %	26 km/h	27.6 °C
December	34 mm	7	12 h/day	55 %	73 %	24 km/h	28.0 °C

Where Parnaíba ranks

Ranking	Position	Value
The warmest places in South America in November	7th of 50	33 °C
The warmest places in South America in December	11th of 50	32 °C
The warmest places in South America in October	21st of 50	33 °C
The driest places in South America in September	24th of 50	1.5 mm
The warmest places in South America year-round	26th of 50	31 °C
The driest places in South America in November	27th of 50	8.0 mm

Planning a trip? See the best time to visit Parnaíba.

QuestionsCommon questions about Parnaíba’s climate

When is the best time to visit Parnaíba?

That depends on what you want, so the honest answer is a comparison rather than a single month. February, March, April sit closest to 20 °C on average, September is the warmest month and September the driest. The month-by-month table above has the full picture.

How hot does Parnaíba get?

In September, the warmest month, daily highs average 34 °C. About 250 days a year pass 30 °C. The highest value in the 1991–2020 record is 37 °C.

How cold does it get in winter?

Nights average 25 °C in March, the coldest month. Freezing nights are not part of a normal year here.

Which month is wettest in Parnaíba?

March, averaging 269 mm over 28 days with rain. The driest month is September with 2 mm. The year as a whole averages 1,092 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Parnaíba rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: -2.905°, -41.777° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.