Guaynabo weather in January

In January, Guaynabo sees average daytime highs of 26°C and overnight lows near 22°C, with 49 mm of rain across 15.7 wet days and about 11 hours of daylight. It is the 12th-warmest and 11th-wettest month of the year here.

Day-to-day highs hold fairly steady near 26°C through the month. The sky is clear or mostly clear about 49% of the time in January, and the air most often feels muggy.

Daylight stretches from about 10 h 54 min at the start of January to 11 h 12 min by month's end. Set against the rest of the year, January is Guaynabo's 2nd-clearest and 5th-windiest month. For the whole year in context, see Guaynabo's year-round climate.

Daytime high
26°
12th warmest
Overnight low
22°
3rd coldest
Rainfall
49 mm
15.7 wet days
Daylight
11 hours
7:03 AM – 6:04 PM
Cloud cover
44%
2nd clearest
Wind
11 km/h
5th windiest
Solar energy
4.65 kWh/m²
Travel score
6.0
out of 10

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 26°C through the month.

A typical January day in Guaynabo reaches about 26°C in the afternoon and slips back to 22°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 28°C. Set against its neighbours, January runs on par with December and on par with February.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12722
22722
32722
42722
52722
62622
72622
82622
92622
102622
112622
122622
132622
142622
152622
162622
172621
182621
192621
202621
212621
222621
232621
242621
252621
262621
272621
282621
292621
302621
312621

How January really feels in Guaynabo

Once humidity and wind are folded in, January averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

January sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Guaynabo weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 22°4915.7116.0
Feb27° / 21°391311.46.2
Mar27° / 22°5514.811.96.0
Apr28° / 22°8717.712.45.3
May28° / 23°14221.912.94.2
Jun29° / 24°9920.813.14.0
Jul29° / 24°11021.8133.9
Aug30° / 25°1272412.63.6
Sep29° / 24°16825.212.13.4
Oct29° / 24°15624.911.63.6
Nov28° / 23°12422.311.14.5
Dec27° / 22°5916.510.95.8

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 49% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 32% of January, with mostly cloudy or overcast conditions the remaining 19%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17921
28020
38020
48020
58119
68020
78020
88020
98119
108119
118020
128020
138020
148020
158020
168020
178020
188119
198119
208119
218119
228218
238218
248218
258218
268317
278317
288317
298317
308416
318416

Chance of precipitation in January

Any precipitation

Guaynabo gets around 49 mm of rain over 15.7 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 51% and peaks near 55% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
153
253
354
454
554
654
755
855
954
1054
1154
1253
1353
1452
1552
1651
1750
1850
1949
2048
2148
2248
2347
2447
2547
2647
2747
2847
2947
3047
3147

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January lands in the muggy band about 61% of days. Sticky, muggy-or-worse air turns up on roughly 96% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1034453
2024652
3024751
4024849
5025048
6025147
7025345
8025444
9025543
10025642
11025741
12025939
13125938
14126037
15126136
16126334
17126433
18136432
19136630
20136729
21146728
22146827
23156826
24057025
25067024
26067024
27077023
28077023
29087022
30087022
31087022

Wind in January

Winds average 11 km/h in January.

Across January, daily wind ranges from about 11 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
611calm
711calm
811calm
911calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm
3111calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 10 h 54 min at the start of January to 11 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over January. Sunrise moves from 7:00 AM to 7:03 AM, and sunset from 5:55 PM to 6:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.97:005:55
210.97:005:56
310.97:015:56
410.97:015:57
510.97:015:57
610.97:025:58
710.97:025:59
810.97:025:59
911.07:026:00
1011.07:036:00
1111.07:036:01
1211.07:036:02
1311.07:036:02
1411.07:036:03
1511.07:036:03
1611.07:036:04
1711.07:046:05
1811.07:046:05
1911.07:046:06
2011.07:046:06
2111.17:046:07
2211.17:046:08
2311.17:046:08
2411.17:046:09
2511.17:046:09
2611.17:036:10
2711.17:036:11
2811.17:036:11
2911.17:036:12
3011.27:036:12
3111.27:036:13

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 4.65 kWh/m².

For context, solar energy here swings from a low near 4.39 kWh/m² to a high of 6.55 kWh/m² in June across the year — January's 4.65 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.4Bright
24.5Bright
34.5Bright
44.5Bright
54.5Bright
64.5Bright
74.5Bright
84.5Bright
94.5Bright
104.5Bright
114.6Bright
124.6Bright
134.6Bright
144.6Bright
154.6Bright
164.7Bright
174.7Bright
184.7Bright
194.7Bright
204.7Bright
214.7Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.9Bright
284.9Bright
294.9Bright
304.9Bright
315.0Bright
Planning a trip in January

Hazard calendar for Guaynabo

In seasonPeak

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

Guaynabo sits in the Atlantic hurricane belt; the season peaks August–October.

Guaynabo sees seasonal dust haze (July), heaviest in July.

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

Is January a good time to visit Guaynabo?

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

6.0
Sightseeing
2nd-best month of the year
5.9
Beach & pool
3rd-best month of the year

January is a reasonable time to visit Guaynabo for sightseeing.

What to pack for Guaynabo in January

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

In January, Guaynabo sees daytime highs around 26°C and nights near 22°C. Pack rain gear. Worth having: light clothes and sun protection. About 16 days see rain.

rain gearlight clothessun protection

Sea temperature near Guaynabo in January

The nearest coast averages about 27°C 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 30 km away) is warmest in September at about 29°C and coldest in February near 26°C.

The water stays above 20°C all year — warm enough for a swim any month.

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb26Warm
Mar26Warm
Apr27Warm
May27Warm
Jun28Warm
Jul28Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov28Tropical
Dec27Warm

UV index in Guaynabo in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January 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 Guaynabo peaks around April 13 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 7 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highApr 13UV 13Dec 16UV 7
UV index (midday)Level
Jan8Very high
Feb10Extreme
Mar12Extreme
Apr13Extreme
May11Extreme
Jun12Extreme
Jul12Extreme
Aug12Extreme
Sep12Extreme
Oct10Very high
Nov8Very high
Dec7High

Air quality in Guaynabo 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 Guaynabo is worst in July — around 25 µg/m³ PM2.5 (moderate), about 4.7× the cleanest month (January, 5 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1125 µg/m³Jan 15 µg/m³
PM2.5 (µg/m³)Level
Jan5Good
Feb7Good
Mar7Good
Apr9Good
May14Moderate
Jun24Moderate
Jul25Moderate
Aug20Moderate
Sep15Moderate
Oct15Moderate
Nov8Good
Dec5Good
Location & terrain

Where is Guaynabo?

Guaynabo sits at 18.4°N, 66.1°W, 47 m above sea level, in Puerto Rico. The nearest listed city is Bayamón, 7.0 km away.

Carolina

Topography around Guaynabo

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

Within 3 km, the terrain around Guaynabo has only modest variations in elevation — a maximum elevation change of 192 m around an average of 64 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 654 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,308 m.

The land around Guaynabo is covered by trees (51%) and artificial surfaces (45%) within 3 km, trees (54%) and artificial surfaces (28%) within 16 km, and water (61%) and trees (30%) within 80 km.

3 km
192 m
16 km
654 m
80 km
1,308 m
treesgrasslandartificial surfacesbare terrainwaterwetland
January weather nearby: Bayamón 7.0 km · Cataño 9.0 km · Trujillo Alto 11 km · Candelaria 12 km · San Juan 12 km · Levittown 13 km · Caguas 15 km · Carolina 16 km

Puerto Rico travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 78% of US
price level, 2025
GDP per capita
$40,620
2025
Happiness
7.0 / 10
World Happiness, 2015
Safe drinking water
99%
of population, 2024
Homicide rate
14.6
per 100k, 2023
Income group
High
World Bank
Religion
Roman Catholic 56%Protestant 33%none 7%other 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 Guaynabo (18.3575°, -66.111°, elevation 47 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).