Round Mountain Weather Records (USC00047581)

Record envelope, standing records and threshold days for Round Mountain (USC00047581), California, United States, with 41 years of record.

Key Facts for Round Mountain

Round Mountain (USC00047581) is a weather station in California, United States at 40.80 latitude and -121.94 longitude, 640 m (2,100 ft) above sea level.
The station reports from 1970 to 2010, 41 years of record.
716 records set at Round Mountain still stand.
Records are tracked for prcp, snow, snwd: an element needs 30 years of data to be eligible.
Round Mountain set a daily record snowfall of 2.5 cm (1.0 in) on 3 March 2010.

About the Station

Location: California, United States, 40.80 latitude, -121.94 longitude.
Elevation: 640 m (2,100 ft).
Period of record: 1970 to 2010, 41 years.
Eligible elements: prcp, snow, snwd.

Daily Record Envelope and 2026

0 days at or beyond a record

The band shows the record high and record low for each calendar day at Round Mountain. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Round Mountain, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	n/a	n/a	n/a	n/a
Feb	21.1 C (70.0 F)	-4.4 C (24.1 F)	n/a	n/a
Mar	n/a	n/a	n/a	n/a
Apr	26.1 C (79.0 F)	-4.4 C (24.1 F)	n/a	n/a
May	n/a	n/a	n/a	n/a
Jun	36.7 C (98.1 F)	2.2 C (36.0 F)	n/a	n/a
Jul	n/a	n/a	n/a	n/a
Aug	n/a	n/a	n/a	n/a
Sep	n/a	n/a	n/a	n/a
Oct	32.2 C (90.0 F)	-3.9 C (25.0 F)	n/a	n/a
Nov	24.4 C (75.9 F)	-2.2 C (28.0 F)	n/a	n/a
Dec	22.2 C (72.0 F)	-5.0 C (23.0 F)	n/a	n/a

Which Years Hold Standing Records

716 standing records

716 records at Round Mountain still stand. 1972 holds the most, with 242.

All-Time Record Progression

2 new records

2 all-time records were set at Round Mountain between 29 December 2003 and 23 December 2008. Each dot is a new record.

Wettest Day of Each Month

Nov: 151.4 mm (6.0 in)

The wettest day on record for each calendar month at Round Mountain. The most was 151.4 mm (6.0 in) on 16 November 1981.

Record daily precipitation for each month at Round Mountain
Month	Record daily precipitation (mm)	Date
Jan	134.6 mm (5.3 in)	2 January 1997
Feb	136.7 mm (5.4 in)	13 February 1979
Mar	122.9 mm (4.8 in)	8 March 1986
Apr	82.6 mm (3.3 in)	17 April 1993
May	101.6 mm (4.0 in)	1 May 1995
Jun	51.8 mm (2.0 in)	27 June 1971
Jul	39.6 mm (1.6 in)	18 July 2007
Aug	46.5 mm (1.8 in)	30 August 1984
Sep	85.1 mm (3.4 in)	8 September 1985
Oct	137.4 mm (5.4 in)	30 October 1992
Nov	151.4 mm (6.0 in)	16 November 1981
Dec	117.9 mm (4.6 in)	9 December 1996

Period of Record Coverage

1970 to 1981

6 years of record at Round Mountain, 1970 to 1981. 6 years have data for under 90 percent of days and are left out of rankings: 1970, 1972, 1975, 1976, 1980, 1981.

Latest Records

Latest records at Round Mountain
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
3 March 2010	Round Mountain, US	daily snowfall	2.5 cm (1.0 in)	1.2 cm (0.5 in)	4 years	7 of 100 (Routine)
15 December 2009	Round Mountain, US	daily rain	57.2 mm (2.3 in)	6.7 mm (0.26 in)	27 years	14 of 100 (Routine)
13 October 2009	Round Mountain, US	daily rain	73.9 mm (2.9 in)	33.3 mm (1.3 in)	28 years	28 of 100 (Routine)
14 September 2009	Round Mountain, US	daily rain	6.4 mm (0.25 in)	5.4 mm (0.21 in)	24 years	14 of 100 (Routine)
6 May 2009	Round Mountain, US	daily rain	19.6 mm (0.8 in)	8.9 mm (0.35 in)	4 years	10 of 100 (Routine)
31 December 2008	Round Mountain, US	daily snow depth	61.0 cm (24.0 in)	17.8 cm (7.0 in)	5 years	17 of 100 (Routine)
30 December 2008	Round Mountain, US	daily snow depth (Tie)	63.5 cm (25.0 in)	tie	5 years	1 of 100 (Routine)
29 December 2008	Round Mountain, US	daily snow depth (Tie)	68.6 cm (27.0 in)	tie	5 years	1 of 100 (Routine)
28 December 2008	Round Mountain, US	daily snow depth	63.5 cm (25.0 in)	43.2 cm (17.0 in)	38 years	47 of 100 (Notable)
27 December 2008	Round Mountain, US	daily snow depth	58.4 cm (23.0 in)	33.0 cm (13.0 in)	38 years	39 of 100 (Notable)
26 December 2008	Round Mountain, US	daily snow depth	58.4 cm (23.0 in)	33.0 cm (13.0 in)	38 years	39 of 100 (Notable)
25 December 2008	Round Mountain, US	daily snow depth	63.5 cm (25.0 in)	27.9 cm (11.0 in)	29 years	32 of 100 (Routine)
24 December 2008	Round Mountain, US	daily snow depth	71.1 cm (28.0 in)	20.3 cm (8.0 in)	29 years	26 of 100 (Routine)
23 December 2008	Round Mountain, US	all-time snow depth	76.2 cm (30.0 in)	7.6 cm (3.0 in)	4 years	29 of 100 (Routine)
22 December 2008	Round Mountain, US	daily snow depth	50.8 cm (20.0 in)	20.3 cm (8.0 in)	38 years	29 of 100 (Routine)
21 December 2008	Round Mountain, US	daily snow depth	45.7 cm (18.0 in)	15.2 cm (6.0 in)	38 years	25 of 100 (Routine)
20 December 2008	Round Mountain, US	daily snow depth	35.6 cm (14.0 in)	17.8 cm (7.0 in)	38 years	27 of 100 (Routine)
19 December 2008	Round Mountain, US	daily snow depth	30.5 cm (12.0 in)	17.8 cm (7.0 in)	6 years	17 of 100 (Routine)
18 December 2008	Round Mountain, US	daily snow depth	33.0 cm (13.0 in)	20.3 cm (8.0 in)	38 years	29 of 100 (Routine)
17 December 2008	Round Mountain, US	daily snow depth	33.0 cm (13.0 in)	20.3 cm (8.0 in)	38 years	29 of 100 (Routine)

Extremes by Year

1970 to 2010

Yearly extremes at Round Mountain: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	36.7 C (98.1 F)	1976	23.3 C (73.9 F)	6
Coldest night (TNn)	-5.0 C (23.0 F)	1975	-4.4 C (24.1 F)	6
Wettest day (Rx1day)	151.4 mm (6.0 in)	1981	94.0 mm (3.7 in)	40
Wettest five days (Rx5day)	413.2 mm (16.3 in)	1981	225.3 mm (8.9 in)	40
Longest dry spell (CDD)	157 days	2002	66 days	40

Hottest day (TXx)

The hottest day of the year at Round Mountain, 1970 to 2010. The record is 36.7 C (98.1 F) in 1976, marked on the chart; the median year is 23.3 C (73.9 F).

Hottest day (TXx) at Round Mountain by year
Year	Hottest day (TXx)
1970	24.4 C (75.9 F)
1971	n/a
1972	32.2 C (90.0 F)
1973	n/a
1974	n/a
1975	21.1 C (70.0 F)
1976	36.7 C (98.1 F)
1977	n/a
1978	n/a
1979	n/a
1980	22.2 C (72.0 F)
1981	21.1 C (70.0 F)
1982	n/a
1983	n/a
1984	n/a
1985	n/a
1986	n/a
1987	n/a
1988	n/a
1989	n/a
1990	n/a
1991	n/a
1992	n/a
1993	n/a
1994	n/a
1995	n/a
1996	n/a
1997	n/a
1998	n/a
1999	n/a
2000	n/a
2002	n/a
2003	n/a
2004	n/a
2005	n/a
2006	n/a
2007	n/a
2008	n/a
2009	n/a
2010	n/a

Coldest night (TNn)

The coldest night of the year at Round Mountain, 1970 to 2010. The record is -5.0 C (23.0 F) in 1975, marked on the chart; the median year is -4.4 C (24.1 F).

Coldest night (TNn) at Round Mountain by year
Year	Coldest night (TNn)
1970	-2.2 C (28.0 F)
1971	n/a
1972	-4.4 C (24.1 F)
1973	n/a
1974	n/a
1975	-5.0 C (23.0 F)
1976	2.2 C (36.0 F)
1977	n/a
1978	n/a
1979	n/a
1980	-5.0 C (23.0 F)
1981	-4.4 C (24.1 F)
1982	n/a
1983	n/a
1984	n/a
1985	n/a
1986	n/a
1987	n/a
1988	n/a
1989	n/a
1990	n/a
1991	n/a
1992	n/a
1993	n/a
1994	n/a
1995	n/a
1996	n/a
1997	n/a
1998	n/a
1999	n/a
2000	n/a
2002	n/a
2003	n/a
2004	n/a
2005	n/a
2006	n/a
2007	n/a
2008	n/a
2009	n/a
2010	n/a

Wettest day (Rx1day)

The wettest day of the year at Round Mountain, 1970 to 2010. The record is 151.4 mm (6.0 in) in 1981, marked on the chart; the median year is 94.0 mm (3.7 in).

Wettest day (Rx1day) at Round Mountain by year
Year	Wettest day (Rx1day)
1970	105.4 mm (4.1 in)
1971	108.7 mm (4.3 in)
1972	64.3 mm (2.5 in)
1973	108.7 mm (4.3 in)
1974	115.6 mm (4.6 in)
1975	86.1 mm (3.4 in)
1976	74.4 mm (2.9 in)
1977	110.2 mm (4.3 in)
1978	74.7 mm (2.9 in)
1979	136.7 mm (5.4 in)
1980	106.4 mm (4.2 in)
1981	151.4 mm (6.0 in)
1982	86.9 mm (3.4 in)
1983	85.1 mm (3.4 in)
1984	74.4 mm (2.9 in)
1985	85.1 mm (3.4 in)
1986	122.9 mm (4.8 in)
1987	109.2 mm (4.3 in)
1988	96.0 mm (3.8 in)
1989	74.4 mm (2.9 in)
1990	73.7 mm (2.9 in)
1991	115.6 mm (4.6 in)
1992	137.4 mm (5.4 in)
1993	99.8 mm (3.9 in)
1994	58.4 mm (2.3 in)
1995	101.6 mm (4.0 in)
1996	117.9 mm (4.6 in)
1997	134.6 mm (5.3 in)
1998	91.9 mm (3.6 in)
1999	82.6 mm (3.3 in)
2000	105.4 mm (4.1 in)
2002	113.5 mm (4.5 in)
2003	69.1 mm (2.7 in)
2004	85.9 mm (3.4 in)
2005	84.3 mm (3.3 in)
2006	125.0 mm (4.9 in)
2007	57.9 mm (2.3 in)
2008	66.0 mm (2.6 in)
2009	73.9 mm (2.9 in)
2010	56.9 mm (2.2 in)

Wettest five days (Rx5day)

The wettest five days of the year at Round Mountain, 1970 to 2010. The record is 413.2 mm (16.3 in) in 1981, marked on the chart; the median year is 225.3 mm (8.9 in).

Wettest five days (Rx5day) at Round Mountain by year
Year	Wettest five days (Rx5day)
1970	243.1 mm (9.6 in)
1971	169.2 mm (6.7 in)
1972	179.4 mm (7.1 in)
1973	306.1 mm (12.1 in)
1974	349.8 mm (13.8 in)
1975	244.1 mm (9.6 in)
1976	227.3 mm (8.9 in)
1977	228.4 mm (9.0 in)
1978	189.2 mm (7.4 in)
1979	225.9 mm (8.9 in)
1980	253.9 mm (10.0 in)
1981	413.2 mm (16.3 in)
1982	232.3 mm (9.1 in)
1983	224.7 mm (8.8 in)
1984	144.0 mm (5.7 in)
1985	201.4 mm (7.9 in)
1986	278.7 mm (11.0 in)
1987	228.3 mm (9.0 in)
1988	183.2 mm (7.2 in)
1989	183.4 mm (7.2 in)
1990	154.5 mm (6.1 in)
1991	238.6 mm (9.4 in)
1992	262.9 mm (10.4 in)
1993	182.7 mm (7.2 in)
1994	117.4 mm (4.6 in)
1995	231.4 mm (9.1 in)
1996	214.8 mm (8.5 in)
1997	336.6 mm (13.3 in)
1998	226.8 mm (8.9 in)
1999	210.1 mm (8.3 in)
2000	187.5 mm (7.4 in)
2002	298.1 mm (11.7 in)
2003	169.2 mm (6.7 in)
2004	182.8 mm (7.2 in)
2005	260.6 mm (10.3 in)
2006	232.1 mm (9.1 in)
2007	135.4 mm (5.3 in)
2008	166.8 mm (6.6 in)
2009	100.4 mm (4.0 in)
2010	118.2 mm (4.7 in)

Longest dry spell (CDD)

The longest dry spell of the year at Round Mountain, 1970 to 2010. The record is 157 days in 2002, marked on the chart; the median year is 66 days.

Longest dry spell (CDD) at Round Mountain by year
Year	Longest dry spell (CDD)
1970	80 days
1971	62 days
1972	66 days
1973	41 days
1974	82 days
1975	51 days
1976	53 days
1977	66 days
1978	62 days
1979	103 days
1980	70 days
1981	104 days
1982	57 days
1983	41 days
1984	84 days
1985	36 days
1986	127 days
1987	95 days
1988	66 days
1989	52 days
1990	62 days
1991	93 days
1992	93 days
1993	68 days
1994	110 days
1995	43 days
1996	65 days
1997	31 days
1998	65 days
1999	67 days
2000	34 days
2002	157 days
2003	82 days
2004	101 days
2005	106 days
2006	111 days
2007	47 days
2008	59 days
2009	42 days
2010	13 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.

Rainfall Return Levels

34 years, 1971 to 2008

A day with at least 93.3 mm (3.7 in) of rain is expected about once in 2 years. A day with at least 162.4 mm (6.4 in) of rain is expected about once in 100 years.

Rainfall return levels at Round Mountain: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	93.3 mm (3.7 in)
5 years	115.6 mm (4.6 in)
10 years	128.6 mm (5.1 in)
25 years	143.5 mm (5.6 in)
50 years	153.4 mm (6.0 in)	Longer than the 34 years of record
100 years	162.4 mm (6.4 in)	Longer than the 34 years of record

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 34 years of values from 1971 to 2008.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 151.4 mm (6.0 in) in 1981; 137.4 mm (5.4 in) in 1992; 136.7 mm (5.4 in) in 1979.

Download the Data

Data for Round Mountain standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Round Mountain 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).

Date	Kind	Detail
2003-12-29	Record snow depth	Record snow depth 68.6 cm (27.0 in)
2008-12-23	Record snow depth	Record snow depth 76.2 cm (30.0 in)