Hermosillo climate

Name: Hermosillo
Address: MX

Hermosillo is warmest in June, with average highs of 39 °C, and coldest in January, when nights average 9.4 °C. September is the wettest month (54 mm) and May the driest (0.4 mm). Figures are 1991–2020 climate normals.

Across a full year Hermosillo averages 241 mm of rain, 298 days above 25 °C and 0 days below freezing.

Mexico · population 812,229 · 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 June 39 °C
Coldest month January 9.4 °C
Driest month May 0 mm
Wettest month September 54 mm
Least cloud June 15 % cloud
Hottest on record June 47 °C
Coldest on record February -0.7 °C

What to expectHermosillo through the year

Hermosillo has a clear annual cycle: average daily highs run from 24 °C in January to 39 °C in June, a swing of 17 °C in mean temperature across the year.

Counted across a normal year, 298 days a year reach 25 °C, 225 of them reach 30 °C, 0 nights drop below freezing. The warmest reading in the 1991–2020 record is 47 °C, in June.

Rain is strongly seasonal. September averages 54 mm against 0 mm in May — 136 times as much. Planning around the dry months matters more here than planning around temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	24.0 °C	11 mm	32 %
February	25.5 °C	15 mm	37 %
March	28.8 °C	8 mm	29 %
April	32.0 °C	1 mm	24 %
May	35.3 °C	under 1 mm	16 %
June	39.3 °C	4 mm	15 %
July	38.7 °C	39 mm	47 %
August	37.9 °C	53 mm	45 %
September	36.3 °C	54 mm	26 %
October	33.4 °C	21 mm	18 %
November	28.1 °C	15 mm	27 %
December	23.2 °C	20 mm	32 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	24.0 °C	9.4 °C	16.0 °C	33.8 °C	0.8 °C	13	1
February	25.5 °C	10.3 °C	17.3 °C	36.9 °C	-0.7 °C	15	4
March	28.8 °C	12.4 °C	20.4 °C	38.8 °C	5.6 °C	26	13
April	32.0 °C	14.9 °C	23.6 °C	40.5 °C	7.4 °C	29	22
May	35.3 °C	18.2 °C	27.1 °C	44.0 °C	10.8 °C	31	29
June	39.3 °C	23.4 °C	31.5 °C	47.1 °C	15.0 °C	30	30
July	38.7 °C	26.7 °C	32.3 °C	46.2 °C	19.5 °C	31	31
August	37.9 °C	26.7 °C	31.8 °C	45.8 °C	20.8 °C	31	31
September	36.3 °C	24.5 °C	29.9 °C	44.0 °C	16.2 °C	30	29
October	33.4 °C	19.2 °C	26.0 °C	41.8 °C	9.2 °C	30	25
November	28.1 °C	13.6 °C	20.4 °C	39.4 °C	5.0 °C	23	10
December	23.2 °C	9.5 °C	15.6 °C	31.7 °C	2.2 °C	10	0

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	11 mm	2	10 h/day	32 %	48 %	14 km/h
February	15 mm	2	11 h/day	37 %	47 %	16 km/h
March	8 mm	1	12 h/day	29 %	37 %	18 km/h
April	1 mm	0	13 h/day	24 %	29 %	20 km/h
May	under 1 mm	0	14 h/day	16 %	27 %	20 km/h
June	4 mm	1	14 h/day	15 %	32 %	20 km/h
July	39 mm	7	14 h/day	47 %	49 %	17 km/h
August	53 mm	9	13 h/day	45 %	57 %	15 km/h
September	54 mm	7	12 h/day	26 %	59 %	15 km/h
October	21 mm	2	11 h/day	18 %	46 %	15 km/h
November	15 mm	1	11 h/day	27 %	45 %	14 km/h
December	20 mm	2	10 h/day	32 %	51 %	14 km/h

How Hermosillo compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Hermosillo	39 °C	9.4 °C	241 mm	298
Ciudad Obregón · Mexico	38 °C	11 °C	337 mm	326
Nogales · Mexico	34 °C	2.3 °C	423 mm	200
Tucson · United States	38 °C	4.2 °C	251 mm	235
Cuauhtémoc · Mexico	29 °C	1.0 °C	426 mm	104
Los Mochis · Mexico	35 °C	13 °C	339 mm	329
Chihuahua · Mexico	34 °C	3.8 °C	295 mm	221

Where Hermosillo ranks

Ranking	Position	Value
The driest places in North America in May	3rd of 50	0.4 mm
The warmest places in North America in October	3rd of 50	33 °C
The warmest places in North America in June	5th of 50	39 °C
The warmest places in North America in September	5th of 50	36 °C
Places with the best weather in North America in December	6th of 50	96/100
The warmest places in North America in May	6th of 50	35 °C

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

QuestionsCommon questions about Hermosillo’s climate

When is the best time to visit Hermosillo?

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

How hot does Hermosillo get?

In June, the warmest month, daily highs average 39 °C. About 225 days a year pass 30 °C. The highest value in the 1991–2020 record is 47 °C.

How cold does it get in winter?

Nights average 9.4 °C in January, the coldest month. A normal year has 0 nights below freezing.

Which month is wettest in Hermosillo?

September, averaging 54 mm over 7 days with rain. The driest month is May with 0 mm. The year as a whole averages 241 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 Hermosillo 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: 29.089°, -110.967° (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.