Ontario, CA weather in March
Expect mild, mostly dry weather in Ontario in March, with highs near 72°F and lows near 49°F. Rain falls on about 5 days. Great for outdoor plans.
- Normal high
- 72°F
- Normal low
- 49°F
- Wet days
- 5
- 1.6 in total
- Muggy days
- 0
- dew point 65°F+
How March changes from start to finish
| March 1 | March 31 | |
|---|---|---|
| Normal high | 70°F | 74°F |
| Normal low | 48°F | 49°F |
| Chance of a wet day | 22% | 15% |
| Sunrise / sunset | 6:19 am / 5:46 pm | 6:39 am / 7:10 pm |
| Daylight | 11.5 h | 12.5 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Pacific Time).
A typical March day
- 6 am45°Fdew point 41°F
- 9 am57°Fdew point 43°F
- Noon66°Fdew point 39°F
- 3 pm68°Fdew point 40°F
- 6 pm61°Fdew point 42°F
- 9 pm53°Fdew point 43°F
NOAA hourly normals (local standard time) from March AFB (26 mi away); average wind 5 mph; clear or few clouds in 56% of daytime hours, mostly cloudy or overcast in 36%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F17 of 31
- Hot dayshigh 90°F or more1 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow5 of 31
- Notable rainat least 0.10 in3 of 31
- Freezing nightslow 32°F or below0 of 31
Average days per March, counted from daily records for each year 1991-2020.
Rain in March
Normal precipitation is 1.6 in; a dry March brings about 0.5 in and a wet one about 2.4 in (25th and 75th percentiles). About 1 day brings half an inch or more.
How March varies from year to year
- Warmest March, 1991-20202015: average high 81°F
- Coolest March2006: average high 63°F
- Wettest March2020: 3.9 in
- Driest March2008: 0.05 in
- Highest reading94°F (March 14, 2013)
- Lowest reading33°F (March 12, 2006)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
March compared with February and April
| February | March | April | |
|---|---|---|---|
| Normal high | 68°F | 72°F | 76°F |
| Normal low | 46°F | 49°F | 51°F |
| Wet days | 6 | 5 | 4 |
| Comfortable days | 13 | 17 | 16 |
| Daylight | 11.0 h | 12.0 h | 13.1 h |
Highs change by +4°F from February and +4°F into April.
Nearby alternatives in March
- Warmer: Palm Springs, CA65 mi · high 81°F · 2 wet days
- Drier: Palm Springs, CA65 mi · high 81°F · 2 wet days
- Cooler: Torrance, CA43 mi · high 66°F · 6 wet days
How Ontario ranks in March
- Normal high74th warmest of 378 cities; 8th of 60 in California
- Wet days42nd driest of 378
- Comfortable days40th most of 339
Heating and cooling
March has 172 heating degree days and 23 cooling degree days (base 65°F), 6% of the year's total heating and cooling demand.
Questions
How hot is Ontario in March?
The normal high is 72°F and the normal low is 49°F. From 1991 to 2020 the hottest March reading was 94°F (most recently on March 14, 2013).
Does it rain a lot in Ontario in March?
About 5 days in March have at least 0.01 in of precipitation, and the normal total is 1.6 in. The wettest March in 1991-2020 was in 2020 (3.9 in); the driest was in 2008 (0.05 in).
Is March a good time to visit Ontario?
March ranks 3rd of 12 months on our comfort score for Ontario (71 out of 100). It has about 17 comfortable days and about 1 day at 90°F or hotter. The best months are March, April and May.
Where the numbers come from
- Temperature, rain and frost dates: Ontario Intl Airport (USW00003102), 2.9 mi E of the city center, 949 ft (52 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snowfall and snow depth: San Gabriel Canyon PH (USC00047776), 16 mi WNW of the city center, 744 ft (257 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: March AFB (USW00023119), 26 mi ESE of the city center, 1,516 ft (515 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: March Air Reserve Base (722860-23119), 26 mi ESE of the city center, 1,536 ft (535 ft higher than the city). Hourly observations, 1991-2020.