Chalco weather in December

In December, Chalco sees average daytime highs of 19°C and overnight lows near 5°C, with 12 mm of rain across 2.2 wet days and about 10.9 hours of daylight. It is the 11th-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 19°C through the month. The sky is clear or mostly clear about 56% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 h 54 min at the start of December to 10 h 54 min by month's end. Set against the rest of the year, December is Chalco's 3rd-clearest and 5th-windiest month. For the whole year in context, see Chalco's year-round climate.

Daytime high: 19°; 11th warmest
Overnight low: 5°; 2nd coldest
Rainfall: 12 mm; 2.2 wet days
Daylight: 10 h 48 min; 7:06 AM – 5:57 PM
Cloud cover: 38%; 3rd clearest
Wind: 6 km/h; 5th windiest
Solar energy: 4.99 kWh/m²
Travel score: 7.5; out of 10

Chalco is municipal seat of Chalco, State of México, Mexico.

Air quality: Elevated; PM10 51.9 µg/m³ · 2017
Density: 773/km²; people per km²
Founded: 1824

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

← November Chalco year-round climate January →Best places to visit in December

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 19°C through the month.

A typical December day in Chalco reaches about 19°C in the afternoon and slips back to 5°C overnight — a 14°C spread between the day's warmth and the night's chill. On most days the high lands between 16°C and 21°C. Set against its neighbours, December runs on par with November and on par with January.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Avg high (°C)	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	19	18	18	18	18	18	18	18	18
Avg low (°C)	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	4

	Avg high (°C)	Avg low (°C)
1	19	5
2	19	5
3	19	5
4	19	5
5	19	5
6	19	5
7	19	5
8	19	5
9	19	5
10	19	5
11	19	5
12	19	5
13	19	5
14	19	5
15	19	5
16	19	5
17	19	5
18	19	5
19	19	5
20	19	5
21	19	5
22	19	5
23	19	5
24	18	5
25	18	5
26	18	5
27	18	5
28	18	5
29	18	5
30	18	5
31	18	4

Chalco weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 12th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	19° / 5°	19	3.4	11	7.3
Feb	20° / 6°	17	3.5	11.3	7.8
Mar	22° / 8°	22	5.2	11.9	7.8
Apr	23° / 9°	40	6.9	12.4	7.5
May	23° / 10°	79	12.5	12.9	6.6
Jun	22° / 11°	243	20.1	13.1	4.9
Jul	20° / 10°	345	27	13	3.8
Aug	20° / 10°	337	26.5	12.7	3.8
Sep	20° / 11°	273	23.6	12.1	4.1
Oct	20° / 9°	120	14	11.6	5.6
Nov	19° / 6°	35	5.7	11.1	7.0
Dec	19° / 5°	12	2.2	10.9	7.5

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 56% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 16% of December, with mostly cloudy or overcast conditions the remaining 28%. Skies tend to cloud over as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Clearer (%)	77	77	77	77	76	76	76	76	75	74	73	73	72	72	72	71	71	70	70	70	70	70	70	70	69	69	69	69	70	70	70
Cloudier (%)	23	23	23	23	24	24	24	24	25	26	27	27	28	28	28	29	29	30	30	30	30	30	30	30	31	31	31	31	30	30	30

	Clearer (%)	Cloudier (%)
1	77	23
2	77	23
3	77	23
4	77	23
5	76	24
6	76	24
7	76	24
8	76	24
9	75	25
10	74	26
11	73	27
12	73	27
13	72	28
14	72	28
15	72	28
16	71	29
17	71	29
18	70	30
19	70	30
20	70	30
21	70	30
22	70	30
23	70	30
24	70	30
25	69	31
26	69	31
27	69	31
28	69	31
29	70	30
30	70	30
31	70	30

Chance of precipitation in December

Any precipitation

Chalco gets around 12 mm of rain over 2.2 wet days in December, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 8% and peaks near 9% on the wettest days.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Rain chance (%)	9	9	8	8	7	7	7	7	7	7	7	7	7	7	7	7	7	7	7	7	7	8	8	8	8	8	8	8	8	8	8

	Rain chance (%)
1	9
2	9
3	8
4	8
5	7
6	7
7	7
8	7
9	7
10	7
11	7
12	7
13	7
14	7
15	7
16	7
17	7
18	7
19	7
20	7
21	7
22	8
23	8
24	8
25	8
26	8
27	8
28	8
29	8
30	8
31	8

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Dry (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100
31	100

Wind in December

Winds average 6 km/h in December.

Across December, 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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Wind speed (km/h)	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	6	calm
2	6	calm
3	6	calm
4	6	calm
5	6	calm
6	6	calm
7	6	calm
8	6	calm
9	6	calm
10	6	calm
11	6	calm
12	6	calm
13	6	calm
14	6	calm
15	6	calm
16	6	calm
17	6	calm
18	6	calm
19	6	calm
20	6	calm
21	6	calm
22	6	calm
23	6	calm
24	6	calm
25	6	calm
26	6	calm
27	6	calm
28	6	calm
29	6	calm
30	6	calm
31	6	calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 h 54 min at the start of December to 10 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 0 minutes over December. Sunrise moves from 6:58 AM to 7:13 AM, and sunset from 5:53 PM to 6:04 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Daylight (h)	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.9	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.8	10.9	10.9
Sunrise (AM)	6:58	6:58	6:59	7:00	7:00	7:01	7:01	7:02	7:02	7:03	7:04	7:04	7:05	7:05	7:06	7:06	7:07	7:07	7:08	7:08	7:09	7:09	7:10	7:10	7:11	7:11	7:12	7:12	7:12	7:13	7:13
Sunset (PM)	5:53	5:53	5:53	5:54	5:54	5:54	5:54	5:54	5:55	5:55	5:55	5:56	5:56	5:56	5:57	5:57	5:58	5:58	5:58	5:59	5:59	6:00	6:00	6:01	6:01	6:02	6:02	6:03	6:03	6:04	6:04

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	10.9	6:58	5:53
2	10.9	6:58	5:53
3	10.9	6:59	5:53
4	10.9	7:00	5:54
5	10.9	7:00	5:54
6	10.9	7:01	5:54
7	10.9	7:01	5:54
8	10.9	7:02	5:54
9	10.9	7:02	5:55
10	10.9	7:03	5:55
11	10.9	7:04	5:55
12	10.9	7:04	5:56
13	10.9	7:05	5:56
14	10.9	7:05	5:56
15	10.8	7:06	5:57
16	10.8	7:06	5:57
17	10.8	7:07	5:58
18	10.8	7:07	5:58
19	10.8	7:08	5:58
20	10.8	7:08	5:59
21	10.8	7:09	5:59
22	10.8	7:09	6:00
23	10.8	7:10	6:00
24	10.8	7:10	6:01
25	10.8	7:11	6:01
26	10.8	7:11	6:02
27	10.8	7:12	6:02
28	10.8	7:12	6:03
29	10.8	7:12	6:03
30	10.9	7:13	6:04
31	10.9	7:13	6:04

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.99 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 4.99 kWh/m² to a high of 6.91 kWh/m² in April across the year — December's 4.99 kWh/m² sits near the bottom.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Solar energy (kWh/m²)	5.1	5.1	5.1	5.0	5.0	5.0	5.0	5.0	5.0	5.0	5.0	5.0	5.0	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	5.0	5.0	5.0	5.0	5.0	5.0
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	5.1	Bright
2	5.1	Bright
3	5.1	Bright
4	5.0	Bright
5	5.0	Bright
6	5.0	Bright
7	5.0	Bright
8	5.0	Bright
9	5.0	Bright
10	5.0	Bright
11	5.0	Bright
12	5.0	Bright
13	5.0	Bright
14	4.9	Bright
15	4.9	Bright
16	4.9	Bright
17	4.9	Bright
18	4.9	Bright
19	4.9	Bright
20	4.9	Bright
21	4.9	Bright
22	4.9	Bright
23	4.9	Bright
24	4.9	Bright
25	4.9	Bright
26	5.0	Bright
27	5.0	Bright
28	5.0	Bright
29	5.0	Bright
30	5.0	Bright
31	5.0	Bright

Planning a trip in December

Hazard calendar for Chalco

In seasonPeak

None of Chalco's seasonal hazards are active in December. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Chalco's monsoon runs June–September, when most of the year's rain falls.

Monsoon

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Is December a good time to visit Chalco?

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

7.5

Sightseeing

3rd-best month of the year

3.1

Beach & pool

7th-best month of the year

December is one of the better times to visit Chalco for general sightseeing.

What to pack for Chalco in December

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

In December, Chalco sees daytime highs around 19°C and nights near 5°C. Worth packing: a warm layer and sun protection.

a warm layersun protection

UV index in Chalco in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Chalco peaks around April 10 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 at about 8 (very high).

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	9	12	14	15	11	14	12	14	12	11	9	8
Level	Very high	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Very high	Very high

	UV index (midday)	Level
Jan	9	Very high
Feb	12	Extreme
Mar	14	Extreme
Apr	15	Extreme
May	11	Extreme
Jun	14	Extreme
Jul	12	Extreme
Aug	14	Extreme
Sep	12	Extreme
Oct	11	Extreme
Nov	9	Very high
Dec	8	Very high

Air quality in Chalco in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Chalco is worst in December — around 179 µg/m³ PM2.5 (very unhealthy), and holds fairly steady the rest of the year.

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
PM2.5 (µg/m³)	149	141	126	113	134	126	135	127	136	137	174	179
Level	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Unhealthy	Very unhealthy	Very unhealthy

	PM2.5 (µg/m³)	Level
Jan	149	Unhealthy
Feb	141	Unhealthy
Mar	126	Unhealthy
Apr	113	Unhealthy
May	134	Unhealthy
Jun	126	Unhealthy
Jul	135	Unhealthy
Aug	127	Unhealthy
Sep	136	Unhealthy
Oct	137	Unhealthy
Nov	174	Very unhealthy
Dec	179	Very unhealthy

Location & terrain

Where is Chalco?

Chalco sits at 19.3°N, 98.9°W, 2,245 m above sea level, in Mexico. The nearest listed city is San Mateo Huitzilzingo, 5.0 km away.

Topography around Chalco

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

Within 3 km, the terrain around Chalco has only modest variations in elevation — a maximum elevation change of 25 m around an average of 2,237 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 884 m; within 80 km, extreme variations in elevation — a maximum elevation change of 4,520 m.

The land around Chalco is covered by artificial surfaces (60%) and cropland (26%) within 3 km, artificial surfaces (30%) and cropland (27%) within 16 km, and trees (32%) and cropland (28%) within 80 km.

3 km

25 m

artificial surfaces 60%

16 km

884 m

artificial surfaces 30%

80 km

4,520 m

trees 32%

treesshrubsgrasslandcroplandartificial surfacesbare terrain

← November Chalco year-round climate January →Best places to visit in December

December weather nearby: San Mateo Huitzilzingo 5.0 km · Xico 6.0 km · San Buenaventura 6.0 km · Ixtapaluca 6.0 km · San Jerónimo Cuatro Vientos 7.0 km · San Martín Cuautlalpan 7.0 km · San Francisco Acuautla 10 km · San Isidro 10 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

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 Chalco (19.2617°, -98.8978°, elevation 2,245 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. 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).

	Avg high (°C)	Avg low (°C)
1	19	5
2	19	5
3	19	5
4	19	5
5	19	5
6	19	5
7	19	5
8	19	5
9	19	5
10	19	5
11	19	5
12	19	5
13	19	5
14	19	5
15	19	5
16	19	5
17	19	5
18	19	5
19	19	5
20	19	5
21	19	5
22	19	5
23	19	5
24	18	5
25	18	5
26	18	5
27	18	5
28	18	5
29	18	5
30	18	5
31	18	4

	Clearer (%)	Cloudier (%)
1	77	23
2	77	23
3	77	23
4	77	23
5	76	24
6	76	24
7	76	24
8	76	24
9	75	25
10	74	26
11	73	27
12	73	27
13	72	28
14	72	28
15	72	28
16	71	29
17	71	29
18	70	30
19	70	30
20	70	30
21	70	30
22	70	30
23	70	30
24	70	30
25	69	31
26	69	31
27	69	31
28	69	31
29	70	30
30	70	30
31	70	30

	Rain chance (%)
1	9
2	9
3	8
4	8
5	7
6	7
7	7
8	7
9	7
10	7
11	7
12	7
13	7
14	7
15	7
16	7
17	7
18	7
19	7
20	7
21	7
22	8
23	8
24	8
25	8
26	8
27	8
28	8
29	8
30	8
31	8

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100
31	100

	Avg high (°C)	Avg low (°C)
1	19	5
2	19	5
3	19	5
4	19	5
5	19	5
6	19	5
7	19	5
8	19	5
9	19	5
10	19	5
11	19	5
12	19	5
13	19	5
14	19	5
15	19	5
16	19	5
17	19	5
18	19	5
19	19	5
20	19	5
21	19	5
22	19	5
23	19	5
24	18	5
25	18	5
26	18	5
27	18	5
28	18	5
29	18	5
30	18	5
31	18	4

	Clearer (%)	Cloudier (%)
1	77	23
2	77	23
3	77	23
4	77	23
5	76	24
6	76	24
7	76	24
8	76	24
9	75	25
10	74	26
11	73	27
12	73	27
13	72	28
14	72	28
15	72	28
16	71	29
17	71	29
18	70	30
19	70	30
20	70	30
21	70	30
22	70	30
23	70	30
24	70	30
25	69	31
26	69	31
27	69	31
28	69	31
29	70	30
30	70	30
31	70	30

	Rain chance (%)
1	9
2	9
3	8
4	8
5	7
6	7
7	7
8	7
9	7
10	7
11	7
12	7
13	7
14	7
15	7
16	7
17	7
18	7
19	7
20	7
21	7
22	8
23	8
24	8
25	8
26	8
27	8
28	8
29	8
30	8
31	8

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100
31	100

	Avg high (°C)	Avg low (°C)
1	19	5
2	19	5
3	19	5
4	19	5
5	19	5
6	19	5
7	19	5
8	19	5
9	19	5
10	19	5
11	19	5
12	19	5
13	19	5
14	19	5
15	19	5
16	19	5
17	19	5
18	19	5
19	19	5
20	19	5
21	19	5
22	19	5
23	19	5
24	18	5
25	18	5
26	18	5
27	18	5
28	18	5
29	18	5
30	18	5
31	18	4

	Clearer (%)	Cloudier (%)
1	77	23
2	77	23
3	77	23
4	77	23
5	76	24
6	76	24
7	76	24
8	76	24
9	75	25
10	74	26
11	73	27
12	73	27
13	72	28
14	72	28
15	72	28
16	71	29
17	71	29
18	70	30
19	70	30
20	70	30
21	70	30
22	70	30
23	70	30
24	70	30
25	69	31
26	69	31
27	69	31
28	69	31
29	70	30
30	70	30
31	70	30

	Rain chance (%)
1	9
2	9
3	8
4	8
5	7
6	7
7	7
8	7
9	7
10	7
11	7
12	7
13	7
14	7
15	7
16	7
17	7
18	7
19	7
20	7
21	7
22	8
23	8
24	8
25	8
26	8
27	8
28	8
29	8
30	8
31	8

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100
31	100