Pacific Storm Impacting Hawaii; Atmospheric River Brings Precipitation to the Pacific Northwest and Northern California

A strong weather system will bring the potential for flash flooding, severe thunderstorms, strong to locally damaging non-thunderstorm winds, and high elevation snow to the Hawaiian Islands. Precipitation will overspread most of the eastern third of the country. A prolonged atmospheric river will bring low elevation rain and mountain snow to the Pacific Northwest and California into the Rockies. Read More >

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Temperatures | Wind |Precipitation| Snowfall

...Highlights of 2015...

Annual - ...9th warmest year on record (1939-2015), 106 percent of normal precipitation, 92 percent of normal annual snowfall.
Earliest First Freeze: August 23, 2015
Monthly Temperatures: 2nd warmest September, 6th warmest March, 9th warmest June and October; period of record 1939-2015).
Montly Precipitation: 6th wettest December, 7th wettest May, 7th driest September.
Montly Snowfall: 7th snowiest December.

Temperature Banner

Element	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Average High	37.5	42.1	54.7	58.2	61.1	82.9	86.1	86.2	82.3	66.9	43.7	33.2	61.2
Mean High (1981-2010 Normals)	35.2	37.8	47.9	56.8	67.1	78.8	88.1	86.4	74.3	59.4	44.7	34.2	59.3
Average Low	15.8	18.3	25.1	29.3	37.2	49.9	50.7	50.3	46.4	35.9	21.3	16.4	33.0
Mean Low (1981-2010 Normals)	14.3	15.7	22.4	28.6	37.2	45.7	53.0	51.5	41.4	31.0	21.6	13.5	31.4
Average Temperature	26.6	30.2	39.9	43.7	49.1	66.4	68.4	68.3	64.4	51.4	32.5	24.8	47.1
Mean Average Temperature (1981-2010 Normals)	24.7	26.7	35.2	42.7	52.2	62.2	70.5	69.0	57.9	45.2	33.2	23.8	45.4
Departure from Normal	1.9	3.5	4.7	1.0	-3.1	4.2	-2.1	-0.7	6.5	6.2	-0.7	1.0	1.7
Rank - Coldest to Warmest 76 years of record (P.O.R 12/1939-2015)	52	55	71	44	11	67	11	28	75	71	31	32	68
Highest Daily Maximum	58	62	76	78	79	95	97	97	91	85	70	55	97
Date of Occurrence	27	9	31	14	31	21	4	14	1,26	10	3	8,9	7/23
Lowest Daily Minimum	-20	-8	-13	18	27	46	36	29	34	20	-4	-8	-20
Date of Occurrence	3	22	3	10	1,11	20-22	29	23	8	29	29	29	11/12
Number of Days with:
Maximum >= 90°	0	0	0	0	0	7	10	13	3	0	0	0	33
Maximum <= 32°	9	10	3	0	0	0	0	0	0	0	7	13	42
Minimum <= 32°	27	25	26	20	7	0	0	1	0	13	25	29	173
Minimum <= 0°	7	4	2	0	0	0	0	0	0	0	1	2	16
Record Highs Set or Tied	1	3	2	1	0	0	0	1	2	1	1	0	11
Record Lows Set or Tied	0	0	0	0	0	0	2	1	0	0	0	0	3

Temperature Ranks and Records:

Daily Records:

Max:

January: 58 on the 27th.
February: 60 on the 7th, 61 on the 13^th, 57 on the 14th (tie).
March: 73 on the 15^th, 75 on the 28th.
April: 78 on the 14^th.
August: 95 on the 15^{th (tie)}.
September: 91 on the 26t^{h, 89 on the 27th.}

October: ^{85 on the 10th.}

November: ^{70 on the 3rd.}

Record High So Early in the Season:
None

Min:

July: 43 on the 20th (tie), 36 on the 29t^h.
August: 29 on the 23rd. (also an all-time record low for the month of August).

Record Low So Early in the Season and Earliest First Freeze:

August: 29 on the 23rd.

Warmest Months of March on Record
Rank	Year	Average Temperature °F
1	2012	44.1
2	1986	42.8
3	1994	41.5
4	2007, 1992	40.6
6	2015	39.9
7	1946	39.4
8	1940	38.5

Warmest Months of June on Record
Rank	Year	Average Temperature °F
1	1988	72.5
2	1977	69.3
3	1994	68.4
4	1956	68.3
5	2012	67.9
6	2006	67.7
7	1986	67.4
8	1959	66.8
9	2015, 1940	66.4
11	1952	66.2

Warmest Months of September on Record
Rank	Year	Average Temperature °F
1	1998	64.7
2	2015	64.4
3	1940	64.3
4	1963	64.1
5	1990, 1969, 1952	63.2
8	1948	63.1
9	1994	62.8
10	1954	62.5

Top Ten Warmest Months of October on Record
Rank	Year	Average Temperature °F
1	1994	49.1
2	2012	48.7
3	1954	48.3
4	1981	48.1
5	1992	48.0
6	1940, 1953, 1963	47.3
9	2015, 2006, 1999	47.1

Top Ten Warmest Years on Record
Rank	Year	Average Temperature °F
1	1994	49.1
2	2012	48.7
3	1954	48.3
4	1981	48.1
5	1992	48.0
6	1940, 1953, 1963	47.3
9	2015, 2006, 1999	47.1

Top Ten Coldest Years on Record
Rank	Year	Average Temperature °F
1	1985	42.5
2	1951	43.1
3	1978	43.2
4	1964	43.5
5	1975	43.6
6	2009, 1979, 1968, 1949	43.8
10	1971	43.9
66	2015	47.1


Average Annual Temperature for Period of Record - Click on Graph to Enlarge

Wind Banner

Element	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Average Speed (MPH)	13.5	11.6	11.2	10.3	9.6	8.2	9.8	9.1	11.1	9.9	14.1	16.5	11.2
Maximum 3-sec Gust	50	59	56	63	43	47	62	60	57	56	52	61	63
Direction (tens of degrees)	21	25	24	20	19	35	25	01	5	26	28	21	20
Date of Occurrence	16	7	28	14	3	30	27	17	23	11	18	21	4/14

Precipitation Banner

Element	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Total (inches)	0.52	0.79	0.64	1.66	3.89	1.50	0.57	0.83	0.19	0.94	0.70	1.06	13.29
Mean Precip (1981-2010 Normals)	0.51	0.57	0.82	1.29	2.02	1.61	1.41	0.85	1.08	1.11	0.76	0.49	12.52
Departure from Normal	0.01	0.22	-0.18	0.37	1.87	-0.11	-0.84	-0.02	-0.89	-0.17	-0.06	0.57	0.77
Percent of Normal	102	139	78	129	193	93	40	98	18	85	92	216	106
Rank - Driest to Wettest 76 years (P.O.R 12/1939-2015)	43	61	31	56	70	48	15	51	7	41	40	71	55
Greatest 24-HR Total	0.22	0.30	0.52	0.53	1.13	0.28	0.21	0.73	0.15	0.53	0.24	0.56	1.13
Dates of Occurrence	3	3-4	2-3	17	23-24	16	5-6	3	28	22-23	25-26	14	7/23-24
Number of Days with:
Precipitation >= 0.01	6	8	4	8	18	11	8	4	2	7	7	8	91
Precipitation >= 0.10	2	4	2	3	9	8	3	1	1	2	4	3	42
Precipitation >= 1.00	0	0	0	0	0	0	0	0	0	0	0	0	0
Days with Thunderstorms	0	0	0	1	5	0	0	5	2	0	0	0	13
Daily Precipitaton Records Set or Tied	0	2	1	1	0	0	0	0	0	0	0	0	4

Precipitation Ranks and Records:

One Day Precipitation Records:

February: 0.23 on the 4th, 0.15 on the 16th.
March: 0.48 on the 2nd.

April: 0.47 on the 26^th.

Wettest Months of May on Record
Rank	Year	Precipitation (inches)
1	1978	6.46
2	1995	6.31
3	1971	5.59
4	1991	4.75
5	2008	4.26
6	1952	3.93
7	2015	3.89
8	1975	3.88
9	1957	3.85
10	1962	3.80

Driest Montth of September on Record
Rank	Year	Precpitation (inches)
1	1956	0.07
2	1980, 2011	0.10
4	1975	0.11
5	1969	0.16
6	1979	0.18
7	2015	0.19
8	1983	0.20
9	1970, 1953	0.21

Wettest Months of December on Record
Rank	Year	Precipitation (inches)
1	1982	3.71
2	2010	1.36
3	2014	1.25
4	2013, 1978	1.20
6	2015	1.06
7	1985	1.05
8	1955	1.04

Top Ten Driest Years on Record
Rank	Year	Precpitation (inches)
1	1988	6.56
2	2001	6.76
3	2002	7.05
4	1960	7.34
5	1954	7.70
6	2012	7.88
7	1963	7.90
8	1966	8.14
9	1943	8.91
10	1999, 1956	8.93
56	2015	13.29

Top Ten Wettest Years on Record
Rank	Year	Precipitation (inches)
1	1982	20.48
2	1995	18.94
3	1983	18.41
4	1978	17.64
5	1941	16.24
6	1957	16.12
7	1986	15.92
8	1993	15.91
9	2009	15.77
10	1947	15.40
21	2015	13.29


Annual Precipitation for Period of Record - Click on Graph to Enlarge

Snow Banner

Element	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Total (inches)	6.4	12.4	9.3	4.7	6.3	0.0	0.0	0.0	0.0	0.0	13.3	16.8	69.2
Mean Snowfall (1981-2010 Normals)	9.1	9.8	10.9	11.6	2.9	0.1	0.0	0.0	1.8	7.4	10.3	11.0	74.9
Departure from Normal	-2.7	2.6	-1.6	-6.9	3.4	-0.1	0.0	0.0	-1.8	-7.4	3.0	5.8	-5.7
Percent of Normal	70	127	85	41	217	0	0	0	0	0	129	162	92
Rank - Least Snowiest to Snowiest 76 Years (P.O.R 12/1939-2015)	25	56	30	17	61	NA	NA	NA	1*	1*	56	71	36
Greatest 24-HR Total	3.1	3.3	5.1	3.1	3.3	0.0	0.0	0.0	0.0	0.0	5.8	6.1	6.1
Dates of Occurrence	3	16	2	13	9	NA	NA	NA	NA	NA	25-26	14	12/14
Number of Days with:
Snowfall >= 1.0 inch	2	4	2	2	2	0	0	0	0	0	4	5	21
Daily Snowfall Records Set or Tied	0	2	0	0	1	0	0	0	0	0	0	1	4
* 48 Septembers and 9 Octobers on record with no snowfall.

Snowfall Ranks and Records:

One Day Snowfall Records (inches):

February: 3.3 on the 16th, 2.9 on the 21st.

May: 3.3 on the 9th
December: 6.1 on the 14th

Snowiest Months of December on Record
Rank	Year	Snowfall (inches)
1	1982	62.8
2	1978	25.7
3	1997	23.8
4	2009	19.5
5	2014, 1967	17.8
7	2015, 1977	16.8
9	1968	16.4
10	2007, 1975	16.1

Top Ten Snowiest Years on Record
Rank	Year	Snowfall (inches)
1	1982	137.6
2	1975	124.0
3	1984	121.2
4	1973	118.3
5	1983	114.2
6	1978	112.7
7	2013	107.5
8	1955	103.3
9	1979	103.0
10	1985	101.0
41	2015	69.2



Annual and Seasonal Snowfall for Period of Record - Click on Graph to Enlarge

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Pacific Storm Impacting Hawaii; Atmospheric River Brings Precipitation to the Pacific Northwest and Northern California

Casper 2015 Annual Climate Summary