Monrovia weather in January

In January, Monrovia sees average daytime highs of 59°F and overnight lows near 42°F, with 3.5 in of precipitation across 5.9 wet days and about 10 hours of daylight. It is the 11th-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 59°F through the month. The sky is clear or mostly clear about 48% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 48 min at the start of January to 10 h 18 min by month's end. Set against the rest of the year, January is Monrovia's 11th-clearest and 2nd-windiest month. For the whole year in context, see Monrovia's year-round climate.

Daytime high
59°
11th warmest
Overnight low
42°
2nd coldest
Precipitation
3.5 in
5.9 wet days
Daylight
10 hours
7:03 AM – 5:00 PM
Cloud cover
46%
11th clearest
Wind
4 mph
2nd windiest
Solar energy
3.12 kWh/m²
Travel score
5.3
out of 10

Monrovia is city in the San Gabriel Valley of Los Angeles County, California, United States.

Density
1,055/km²
people per km²
Founded
1887

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

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 59°F through the month.

A typical January day in Monrovia reaches about 59°F in the afternoon and slips back to 42°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 49°F and 70°F. Set against its neighbours, January runs on par with December and on par with February.

30°40°50°60°70°80°151015202531
Avg high (°F)Avg low (°F)
15841
25842
35842
45842
55942
65942
75942
85942
95942
105942
115942
125942
135943
145943
156043
166043
176043
186043
196043
206043
216043
226043
236042
246042
256042
266042
276042
286042
296042
306043
316043

Monrovia weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan59° / 42°3.55.91.1105.3
Feb60° / 43°3.86.91.510.75.2
Mar63° / 45°2.56.7111.76.3
Apr68° / 47°1.040.312.87.6
May73° / 53°0.53013.88.5
Jun81° / 58°0.10.7014.28.5
Jul86° / 64°0.42.10146.4
Aug88° / 65°0.21.9013.36.0
Sep84° / 61°0.31.8012.27.5
Oct76° / 55°0.82.6011.18.7
Nov66° / 47°0.92.90.210.27.6
Dec59° / 42°2.45.20.79.85.3

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 48% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 10% of January, with mostly cloudy or overcast conditions the remaining 41%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
25941
35941
45842
55842
65842
75842
85941
95941
105941
115941
126040
136040
145941
155941
166040
175941
185941
195941
205941
215842
225842
235842
245842
255842
265842
275842
285941
295941
306040
316040

Chance of precipitation in January

Any precipitationSnow

Monrovia gets around 3.5 in of rain and snow over 5.9 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 19% and peaks near 20% on the wettest days, and about 1 day brings snow.

0%10%20%30%151015202531
Rain chance (%)Snow chance (%)
1184
2194
3194
4194
5194
6194
7204
8204
9204
10204
11204
12204
13194
14194
15194
16194
17194
18194
19194
20194
21194
22194
23194
24183
25183
26183
27183
28183
29183
30183
31183

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

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

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in January

Winds average 4 mph in January.

Across January, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 48 min at the start of January to 10 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 30 minutes over January. Sunrise moves from 7:02 AM to 6:57 AM, and sunset from 4:48 PM to 5:14 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.87:024:48
29.87:034:49
39.87:034:49
49.87:034:50
59.87:034:51
69.87:034:52
79.87:034:52
89.87:034:53
99.87:034:54
109.97:034:55
119.97:034:56
129.97:034:56
139.97:034:57
149.97:034:58
159.97:034:59
1610.07:035:00
1710.07:025:01
1810.07:025:02
1910.07:025:03
2010.07:025:04
2110.17:015:05
2210.17:015:05
2310.17:015:06
2410.17:005:07
2510.17:005:08
2610.26:595:09
2710.26:595:10
2810.26:585:11
2910.26:585:12
3010.36:575:13
3110.36:575:14

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 3.12 kWh/m².

For context, solar energy here swings from a low near 2.96 kWh/m² to a high of 8.18 kWh/m² in June across the year — January's 3.12 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.0Moderate
23.0Moderate
33.0Moderate
43.0Moderate
53.0Moderate
63.0Moderate
73.0Moderate
83.0Moderate
93.0Moderate
103.0Moderate
113.0Moderate
123.0Moderate
133.1Moderate
143.1Moderate
153.1Moderate
163.1Moderate
173.2Moderate
183.2Moderate
193.2Moderate
203.2Moderate
213.3Moderate
223.3Moderate
233.3Moderate
243.4Moderate
253.4Moderate
263.4Moderate
273.4Moderate
283.5Moderate
293.5Moderate
303.5Moderate
313.6Moderate
Planning a trip in January

Is January a good time to visit Monrovia?

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

5.3
Sightseeing
10th-best month of the year
0.2
Beach & pool
12th-best month of the year

January is a reasonable time to visit Monrovia for sightseeing.

What to pack for Monrovia in January

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

In January, Monrovia sees daytime highs around 59°F and nights near 42°F. Worth packing: a warm layer. About 6 days see rain.

a warm layer

Sea temperature near Monrovia in January

The nearest coast averages about 59°F in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 29 mi away) is warmest in August at about 68°F and coldest in February near 59°F.

It's comfortable for a long swim from Aug 4 to Sep 13 — about 1.3 months when the water holds above 68°F.

60°65°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°F)Comfort
Jan59Bracing
Feb59Bracing
Mar59Bracing
Apr59Cool
May62Cool
Jun65Cool
Jul67Cool
Aug68Refreshing
Sep68Refreshing
Oct66Cool
Nov63Cool
Dec60Cool

UV index in Monrovia in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Monrovia peaks around July 11 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateVery highExtremeVery highHighModerateJul 11UV 11Dec 16UV 3
UV index (midday)Level
Jan4Moderate
Feb5Moderate
Mar5Moderate
Apr8Very high
May8Very high
Jun11Extreme
Jul11Extreme
Aug10Extreme
Sep8Very high
Oct6High
Nov3Moderate
Dec3Moderate

Air quality in Monrovia in January

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Monrovia is worst in September — around 39 µg/m³ PM2.5 (poor), about 3.2× the cleanest month (May, 12 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateModerateSep 1537 µg/m³May 1612 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb15Moderate
Mar16Moderate
Apr14Moderate
May12Moderate
Jun15Moderate
Jul18Moderate
Aug22Moderate
Sep39Poor
Oct15Moderate
Nov17Moderate
Dec14Moderate
Location & terrain

Where is Monrovia?

Monrovia sits at 34.1°N, 118.0°W, 571 ft above sea level, in United States. The nearest listed city is Duarte, 1.2 mi away.

Topography around Monrovia

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Monrovia.

Within 2 miles, the terrain around Monrovia has significant variations in elevation — a maximum elevation change of 1,785 ft around an average of 686 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 5,932 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 10,013 ft.

The land around Monrovia is covered by artificial surfaces (58%) and trees (31%) within 2 miles, artificial surfaces (43%), shrubs (27%) and trees (23%) within 10 miles, and artificial surfaces (26%) and grassland (20%) within 50 miles.

2 miles
1,785 ft
10 miles
5,932 ft
50 miles
10,013 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Duarte 1.2 mi · Arcadia 1.9 mi · Temple City 4.3 mi · Baldwin Park 5.0 mi · Azusa 5.6 mi · El Monte 5.6 mi · Rosemead 6.2 mi · West Covina 6.2 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Monrovia (34.1481°, -117.9989°, elevation 571 ft), 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. 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).