Ontario Weather Records (USW00024162)

Record envelope, standing records and threshold days for Ontario (USW00024162), Oregon, United States, with 30 years of record.

Key Facts for Ontario

Ontario (USW00024162) is a weather station in Oregon, United States at 44.01 latitude and -117.01 longitude, 667 m (2,188 ft) above sea level.
The station reports from 1997 to 2026, 30 years of record.
1,464 records set at Ontario still stand.
Records are tracked for no element yet: an element needs 30 years of data to be eligible.

About the Station

Location: Oregon, United States, 44.01 latitude, -117.01 longitude.
Elevation: 667 m (2,188 ft).
Period of record: 1997 to 2026, 30 years.
Eligible elements: none yet.

Daily Record Envelope and 2026

30 days at or beyond a record

The band shows the record high and record low for each calendar day at Ontario. The lines show the 2026 daily maximum and minimum. 30 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Ontario, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	12.2 C (54.0 F)	-28.8 C (-19.8 F)	10.6 C (51.1 F)	-11.6 C (11.1 F)
Feb	20.6 C (69.1 F)	-18.2 C (-0.8 F)	11.7 C (53.1 F)	-18.2 C (-0.8 F)
Mar	27.8 C (82.0 F)	-10.6 C (12.9 F)	25.6 C (78.1 F)	-6.0 C (21.2 F)
Apr	32.2 C (90.0 F)	-7.1 C (19.2 F)	26.7 C (80.1 F)	-1.6 C (29.1 F)
May	37.8 C (100.0 F)	-3.3 C (26.1 F)	36.7 C (98.1 F)	2.8 C (37.0 F)
Jun	42.8 C (109.0 F)	2.2 C (36.0 F)	36.7 C (98.1 F)	5.6 C (42.1 F)
Jul	44.4 C (111.9 F)	6.7 C (44.1 F)	40.0 C (104.0 F)	10.0 C (50.0 F)
Aug	42.8 C (109.0 F)	3.9 C (39.0 F)	38.3 C (100.9 F)	11.1 C (52.0 F)
Sep	38.9 C (102.0 F)	-2.8 C (27.0 F)	37.2 C (99.0 F)	3.3 C (37.9 F)
Oct	33.9 C (93.0 F)	-12.7 C (9.1 F)	27.2 C (81.0 F)	-3.9 C (25.0 F)
Nov	23.3 C (73.9 F)	-19.3 C (-2.7 F)	17.8 C (64.0 F)	-6.1 C (21.0 F)
Dec	15.6 C (60.1 F)	-25.5 C (-13.9 F)	14.4 C (57.9 F)	-6.7 C (19.9 F)

Which Years Hold Standing Records

1,464 standing records

1,464 records at Ontario still stand. 1999 holds the most, with 79.

Standing records at Ontario by the year they were set
Year set	Standing records
1997	13
1998	54
1999	79
2000	45
2001	57
2002	67
2003	60
2004	34
2005	45
2006	55
2007	42
2008	43
2009	38
2010	55
2011	51
2012	43
2013	76
2014	60
2015	67
2016	66
2017	54
2018	36
2019	44
2020	39
2021	52
2022	57
2023	41
2024	45
2025	46

Wettest Day of Each Month

Aug: 38.4 mm (1.5 in)

The wettest day on record for each calendar month at Ontario. The most was 38.4 mm (1.5 in) on 21 August 2023.

Record daily precipitation for each month at Ontario
Month	Record daily precipitation (mm)	Date
Jan	21.3 mm (0.8 in)	18 January 2017
Feb	18.3 mm (0.7 in)	14 February 2019
Mar	19.0 mm (0.7 in)	14 March 2023
Apr	14.7 mm (0.6 in)	24 April 2014
May	27.9 mm (1.1 in)	5 May 2005
Jun	19.0 mm (0.7 in)	12 June 2022
Jul	24.4 mm (1.0 in)	4 July 1998
Aug	38.4 mm (1.5 in)	21 August 2023
Sep	25.4 mm (1.0 in)	20 September 2008
Oct	15.7 mm (0.6 in)	24 October 2010
Nov	15.5 mm (0.6 in)	1 November 2014
Dec	29.0 mm (1.1 in)	21 December 2025

Period of Record Coverage

1997 to 2025

29 years of record at Ontario, 1997 to 2025. 1 years have data for under 90 percent of days and are left out of rankings: 1997.

Days with data per year at Ontario
Year	Days with data	Share of year	Complete
1997	171	47%	No
1998	360	99%	Yes
1999	359	98%	Yes
2000	364	99%	Yes
2001	362	99%	Yes
2002	365	100%	Yes
2003	360	99%	Yes
2004	355	97%	Yes
2005	357	98%	Yes
2006	364	100%	Yes
2007	363	99%	Yes
2008	366	100%	Yes
2009	364	100%	Yes
2010	365	100%	Yes
2011	365	100%	Yes
2012	365	100%	Yes
2013	364	100%	Yes
2014	365	100%	Yes
2015	365	100%	Yes
2016	366	100%	Yes
2017	363	99%	Yes
2018	331	91%	Yes
2019	365	100%	Yes
2020	366	100%	Yes
2021	365	100%	Yes
2022	365	100%	Yes
2023	364	100%	Yes
2024	366	100%	Yes
2025	365	100%	Yes

Latest Records

No records were set at this station in the latest data.

Climate Trend

27 complete years, 1998 to 2025

One stripe for each of 27 complete years at Ontario, 1998 to 2025. Blue stripes are years cooler than the station's own mean of 11.5 C (52.7 F); red stripes are warmer. The coolest year was 2011, at 10.3 C (50.5 F), and the warmest was 2021, at 13.1 C (55.5 F). The strongest colour marks a difference of 1.6 C (2.9 F).

Annual mean temperature at Ontario as warming stripes, 1998 to 2025
Year	Annual mean temperature	Difference from the station mean
1998	11.4 C	-0.06 C
1999	10.7 C	-0.83 C
2000	11.2 C	-0.26 C
2001	11.0 C	-0.48 C
2002	11.3 C	-0.20 C
2003	12.4 C	+0.87 C
2004	10.8 C	-0.67 C
2005	10.3 C	-1.16 C
2006	11.4 C	-0.10 C
2007	11.7 C	+0.20 C
2008	10.4 C	-1.06 C
2009	10.6 C	-0.93 C
2010	10.7 C	-0.81 C
2011	10.3 C	-1.23 C
2012	11.9 C	+0.39 C
2013	10.6 C	-0.89 C
2014	11.8 C	+0.29 C
2015	12.6 C	+1.16 C
2016	11.7 C	+0.23 C
2017	10.9 C	-0.62 C
2019	12.0 C	+0.56 C
2020	12.2 C	+0.73 C
2021	13.1 C	+1.59 C
2022	11.6 C	+0.13 C
2023	12.4 C	+0.92 C
2024	12.9 C	+1.40 C
2025	12.3 C	+0.84 C

This station does not have enough complete years (30 are needed) to fit a temperature trend.

A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.

Extremes by Year

1997 to 2026

Yearly extremes at Ontario: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	44.4 C (111.9 F)	2002	40.6 C (105.1 F)	30
Coldest night (TNn)	-28.8 C (-19.8 F)	2017	-15.2 C (4.6 F)	30
Wettest day (Rx1day)	38.4 mm (1.5 in)	2023	17.5 mm (0.7 in)	29
Wettest five days (Rx5day)	50.9 mm (2.0 in)	1998	29.4 mm (1.2 in)	29
Longest dry spell (CDD)	105 days	2018	60 days	29

Hottest day (TXx)

The hottest day of the year at Ontario, 1997 to 2026. The record is 44.4 C (111.9 F) in 2002, marked on the chart; the median year is 40.6 C (105.1 F).

Hottest day (TXx) at Ontario by year
Year	Hottest day (TXx)
1997	38.3 C (100.9 F)
1998	40.6 C (105.1 F)
1999	38.3 C (100.9 F)
2000	39.4 C (102.9 F)
2001	39.4 C (102.9 F)
2002	44.4 C (111.9 F)
2003	43.3 C (109.9 F)
2004	39.4 C (102.9 F)
2005	40.0 C (104.0 F)
2006	42.2 C (108.0 F)
2007	41.1 C (106.0 F)
2008	38.9 C (102.0 F)
2009	39.4 C (102.9 F)
2010	38.9 C (102.0 F)
2011	37.8 C (100.0 F)
2012	40.6 C (105.1 F)
2013	43.3 C (109.9 F)
2014	40.6 C (105.1 F)
2015	42.8 C (109.0 F)
2016	40.6 C (105.1 F)
2017	40.6 C (105.1 F)
2018	40.6 C (105.1 F)
2019	39.4 C (102.9 F)
2020	41.7 C (107.1 F)
2021	41.7 C (107.1 F)
2022	43.9 C (111.0 F)
2023	42.8 C (109.0 F)
2024	42.8 C (109.0 F)
2025	40.0 C (104.0 F)
2026	40.0 C (104.0 F)

Coldest night (TNn)

The coldest night of the year at Ontario, 1997 to 2026. The record is -28.8 C (-19.8 F) in 2017, marked on the chart; the median year is -15.2 C (4.6 F).

Coldest night (TNn) at Ontario by year
Year	Coldest night (TNn)
1997	-10.0 C (14.0 F)
1998	-18.3 C (-0.9 F)
1999	-13.3 C (8.1 F)
2000	-13.3 C (8.1 F)
2001	-12.8 C (9.0 F)
2002	-11.7 C (10.9 F)
2003	-11.1 C (12.0 F)
2004	-18.9 C (-2.0 F)
2005	-20.0 C (-4.0 F)
2006	-13.2 C (8.2 F)
2007	-14.3 C (6.3 F)
2008	-21.0 C (-5.8 F)
2009	-19.3 C (-2.7 F)
2010	-15.5 C (4.1 F)
2011	-17.1 C (1.2 F)
2012	-13.8 C (7.2 F)
2013	-25.5 C (-13.9 F)
2014	-19.3 C (-2.7 F)
2015	-16.6 C (2.1 F)
2016	-23.8 C (-10.8 F)
2017	-28.8 C (-19.8 F)
2018	-12.7 C (9.1 F)
2019	-12.7 C (9.1 F)
2020	-9.9 C (14.2 F)
2021	-14.9 C (5.2 F)
2022	-19.3 C (-2.7 F)
2023	-12.1 C (10.2 F)
2024	-22.1 C (-7.8 F)
2025	-18.2 C (-0.8 F)
2026	-10.6 C (12.9 F)

Wettest day (Rx1day)

The wettest day of the year at Ontario, 1997 to 2026. The record is 38.4 mm (1.5 in) in 2023, marked on the chart; the median year is 17.5 mm (0.7 in).

Wettest day (Rx1day) at Ontario by year
Year	Wettest day (Rx1day)
1997	n/a
1998	26.2 mm (1.0 in)
1999	15.0 mm (0.6 in)
2000	14.2 mm (0.6 in)
2001	11.2 mm (0.4 in)
2002	16.3 mm (0.6 in)
2003	12.7 mm (0.5 in)
2004	13.5 mm (0.5 in)
2005	27.9 mm (1.1 in)
2006	14.2 mm (0.6 in)
2007	18.8 mm (0.7 in)
2008	25.4 mm (1.0 in)
2009	19.6 mm (0.8 in)
2010	21.8 mm (0.9 in)
2011	14.0 mm (0.6 in)
2012	17.5 mm (0.7 in)
2013	13.7 mm (0.5 in)
2014	17.8 mm (0.7 in)
2015	13.7 mm (0.5 in)
2016	10.4 mm (0.4 in)
2017	21.3 mm (0.8 in)
2018	15.0 mm (0.6 in)
2019	18.3 mm (0.7 in)
2020	18.8 mm (0.7 in)
2021	16.0 mm (0.6 in)
2022	19.0 mm (0.7 in)
2023	38.4 mm (1.5 in)
2024	14.5 mm (0.6 in)
2025	29.0 mm (1.1 in)
2026	25.4 mm (1.0 in)

Wettest five days (Rx5day)

The wettest five days of the year at Ontario, 1997 to 2026. The record is 50.9 mm (2.0 in) in 1998, marked on the chart; the median year is 29.4 mm (1.2 in).

Wettest five days (Rx5day) at Ontario by year
Year	Wettest five days (Rx5day)
1997	n/a
1998	50.9 mm (2.0 in)
1999	24.0 mm (0.9 in)
2000	27.4 mm (1.1 in)
2001	21.7 mm (0.9 in)
2002	26.0 mm (1.0 in)
2003	17.6 mm (0.7 in)
2004	21.4 mm (0.8 in)
2005	46.5 mm (1.8 in)
2006	37.6 mm (1.5 in)
2007	19.1 mm (0.8 in)
2008	25.7 mm (1.0 in)
2009	35.1 mm (1.4 in)
2010	32.8 mm (1.3 in)
2011	24.3 mm (1.0 in)
2012	32.0 mm (1.3 in)
2013	19.8 mm (0.8 in)
2014	32.0 mm (1.3 in)
2015	28.0 mm (1.1 in)
2016	20.6 mm (0.8 in)
2017	39.1 mm (1.5 in)
2018	17.8 mm (0.7 in)
2019	41.0 mm (1.6 in)
2020	37.9 mm (1.5 in)
2021	26.4 mm (1.0 in)
2022	29.4 mm (1.2 in)
2023	39.4 mm (1.6 in)
2024	32.5 mm (1.3 in)
2025	41.5 mm (1.6 in)
2026	46.3 mm (1.8 in)

Longest dry spell (CDD)

The longest dry spell of the year at Ontario, 1997 to 2026. The record is 105 days in 2018, marked on the chart; the median year is 60 days.

Longest dry spell (CDD) at Ontario by year
Year	Longest dry spell (CDD)
1997	n/a
1998	39 days
1999	104 days
2000	80 days
2001	44 days
2002	53 days
2003	60 days
2004	38 days
2005	42 days
2006	63 days
2007	69 days
2008	59 days
2009	56 days
2010	52 days
2011	60 days
2012	88 days
2013	78 days
2014	50 days
2015	42 days
2016	70 days
2017	92 days
2018	105 days
2019	64 days
2020	64 days
2021	50 days
2022	71 days
2023	37 days
2024	49 days
2025	32 days
2026	64 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Frost Dates and Growing Season

27 years with a frost

Across 27 years with a frost, the median last spring frost at Ontario falls on 30 April and the median first autumn frost on 11 October, which leaves a median of 166 days between them.

Fitted over all years, the growing season changes by +11.0 days per decade at this station.

Frost dates and growing season at Ontario
Measure	Median, all years	Earliest period	Recent period (1998 to 2025)	Recent against earliest	Fitted trend
Last spring frost	30 April	n/a	30 April	n/a	-3.1 days per decade
First autumn frost	11 October	n/a	11 October	n/a	+7.9 days per decade
Growing days	166 days	n/a	166 days	n/a	+11.0 days per decade

A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.

Download the Data

Data for Ontario standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Ontario threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).