Rialto in Winter
In winter (December, January and February), Rialto sees average daytime highs around 60°F and overnight lows near 41°F, with 8.7 in of precipitation over about 18 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Across winter, daytime highs hold fairly steady around 60°F. The sky is clear or mostly clear about 49% of the time across winter, and the air most often feels dry.
Winter is Rialto's weakest season of the year to visit on our travel score. For the whole year in context, see Rialto's year-round climate.
- Avg daytime high
- 60°F
- coldest season of the year
- Avg overnight low
- 41°F
- Precipitation
- 8.7 in
- 18 wet days
- Avg wind
- 4 mph
- Travel score
- 5.5
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Rialto in Winter
Across winter, daytime highs hold fairly steady around 60°F.
A typical winter day in Rialto reaches about 60°F and drops to 41°F overnight. The warmest of the three months is February, the coolest December.
Rialto weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 60° / 41° | 2.9 | 6.1 | 0.6 | 10 | 5.5 |
| Feb | 61° / 42° | 3.6 | 6.8 | 1.1 | 10.7 | 5.5 |
| Mar | 64° / 45° | 2.2 | 6.2 | 0.8 | 11.7 | 6.6 |
| Apr | 69° / 48° | 1.1 | 3.9 | 0.3 | 12.8 | 7.7 |
| May | 74° / 53° | 0.5 | 2.6 | 0 | 13.7 | 8.6 |
| Jun | 82° / 59° | 0.1 | 0.7 | 0 | 14.2 | 8.2 |
| Jul | 87° / 65° | 0.5 | 2.6 | 0 | 14 | 6.0 |
| Aug | 89° / 66° | 0.4 | 2.8 | 0 | 13.3 | 5.5 |
| Sep | 85° / 62° | 0.3 | 1.8 | 0 | 12.2 | 7.0 |
| Oct | 77° / 54° | 0.7 | 2.4 | 0 | 11.1 | 8.7 |
| Nov | 67° / 46° | 1.0 | 3.1 | 0.2 | 10.2 | 7.7 |
| Dec | 60° / 41° | 2.2 | 5 | 0.4 | 9.8 | 5.6 |
Cloud cover in Winter
The sky is clear or mostly clear about 49% of the time across winter.
Chance of precipitation in Winter
Rialto gets around 8.7 in of rain and snow over 18 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 4 mph across winter.
Sunrise & sunset in Winter
Daylight runs from about 9 h 54 min in early December to 11 h 12 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 3.4 kWh/m².
Is winter a good time to visit Rialto?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a reasonable time to visit Rialto for sightseeing.
What to pack for Rialto in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Rialto sees daytime highs around 60°F and nights near 41°F. Worth packing: a warm layer. About 18 days see rain.
UV index in Rialto in Winter
Clear-sky midday UV across winter averages 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 Rialto peaks around June 23 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 4 | 5 | 5 | 8 | 8 | 11 | 11 | 11 | 8 | 6 | 4 | 3 |
| Level | Moderate | Moderate | High | Very high | Very high | Extreme | Extreme | Extreme | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 4 | Moderate |
| Feb | 5 | Moderate |
| Mar | 5 | High |
| Apr | 8 | Very high |
| May | 8 | Very high |
| Jun | 11 | Extreme |
| Jul | 11 | Extreme |
| Aug | 11 | Extreme |
| Sep | 8 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 3 | Moderate |
Air quality in Rialto in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter falls, not just the annual average.
Air quality in Rialto is worst in September — around 40 µg/m³ PM2.5 (poor), about 5.4× the cleanest month (December, 7 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 8 | 9 | 11 | 10 | 8 | 19 | 12 | 20 | 40 | 10 | 8 | 7 |
| Level | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Poor | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 9 | Good |
| Mar | 11 | Good |
| Apr | 10 | Good |
| May | 8 | Good |
| Jun | 19 | Moderate |
| Jul | 12 | Moderate |
| Aug | 20 | Moderate |
| Sep | 40 | Poor |
| Oct | 10 | Good |
| Nov | 8 | Good |
| Dec | 7 | Good |
Where is Rialto?
Rialto sits at 34.1°N, 117.4°W, 1,257 ft above sea level, in United States. The nearest listed city is Bloomington, 3.1 mi away.
Topography around Rialto
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Rialto.
Within 2 miles, the terrain around Rialto has only modest variations in elevation — a maximum elevation change of 335 ft around an average of 1,250 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 4,675 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 11,417 ft.
The land around Rialto is covered by artificial surfaces (82%) within 2 miles, artificial surfaces (50%) within 10 miles, and shrubs (27%) and artificial surfaces (20%) within 50 miles.
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
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 Rialto (34.1064°, -117.3703°, elevation 1,257 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.