Seattle, WA

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 Graphical Climatology of Seattle: Daily Temperatures and Rainfall, by Year (1945 – Present)

Las Vegas Temperatures, Precipitation and other variables.
The following is a graphical climatology of Seattle, Washington (Seattle-Tacoma Int’l Airport) temperatures, precipitation, and various other parameters, from 1945 into 2024. Presented are daily climatological overview charts (temperature), annual time-series (temperature and precipitation), “climograms” (hour-by-month depictions of temperature, humidity, winds, fog, blowing sand/dust, and thunderstorms), followed by year-to-year graphs that depict daily max/min temperature, daily mean temperature anomalies, daily rainfall, and when applicable daily snowfall/depths. Data were obtained courtesy of the NOAA National Climatic Data Center and the NWS-Seattle online site.
 
 
Latest Update: 1 Dec 2024  — e-mail contact: cjfisk@att.net
 

TEMPERATURE AND RAINFALL CLIMATOLOGIES:

ANNUAL TEMPERATURE AND RAINFALL TIME-SERIES:

HOUR BY MONTH CLIMOGRAMS & OTHER CHARTS:

YEAR-TO-YEAR GRAPHS:

 The uppermost graph below displays “floating-bars” of the daily maxima and minima. Each bar represents an individual day’s temperature range. Superimposed are two line traces, the upper one connecting 1948 to present mean daily maxima, the lower one 1948 to present mean daily minima. The bars depict the varying diurnal, synoptic, long-wave, and seasonal influences on temperature over time, and for effect they are deliberately adjoined with no spaces in-between, lending an enhanced  “signature” look, so to speak, to the time-series.  The same is repeated for the second and third charts below.  

The second chart down shows the arithmetic departures of day-to-day mean temperatures less the corresponding 1948-present calendar-day average means. Vertical lines extending upward from the zero line indicate above average means for the day (colored red), those extending downward indicate below average daily means (colored blue). In the entire series, the most extreme departure of either sign is -31 F on 31 Jan 1950 (associated with a daily maximum: 20 F and daily minimum: 0 F)

(Note: Clicking on the floating-bar charts a second time after they appear on the screen will enlarge them even further).

The third chart down shows the second chart’s departures in deseasonalized or “standardized” form. Standardized anomalies are calculated by dividing the arithmetic anomaly by the climatological mean temperature standard deviation for the calendar day in question, creating “z-scores”. Through 2017, the most extreme z-score was -4.95 z, for 15 Nov 1955.

The fourth chart down depicts daily rainfall, as high as 5.02 inches (20 Oct 2003), the fifth (when applicable) shows snowfall, as high as 20.0 inches (13 Jan 1950), and the sixth (when applicable) snow depth, as high as 21 inches (13 Jan 1969).

YEAR-TO-YEAR GRAPHS – COMPLETE SET OF LINKS

1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 

LINKS TO SOME OF THE MORE INTERESTING YEAR-TO-YEAR  PATTERNS, WITH ACCOMPANYING NOTES

2016  – 89 F on 18 April breaks previous early-season-date-record for an 89 F reading by nearly a month.
2014  – Wettest Spring (Mar-May) in history (16.77″).
2009  – 103 F on 29 July sets new record hottest temperature. 103/71 F Max/Min hottest day (87.0 F Mean).
2006 – November wettest calendar month (15.63″) in history.
1995 –   Warmest Year to date (54.4 F) and until 2014.
1994  – 100 F on 20 July highest yet in history.
1992  – Warmest Year to date (54.3 F).
1985 – Coldest November in history by more than 3 F.  Also 2nd driest calendar year in history (25.13″).
1981– 99 F on 8 August ties record hottest reading in history.
1979  – Driest Spring in history (Mar-May) – 3.24″.
1972  – Pronounced cold spells in late-Jan/early Feb, Sept, and Dec.
1968 – Wettest Summer (Jun-Aug) in history (8.43″).
1960  – 99 F on 8 August, Highest reading to date.
1958 – Warmest Year to date (53.9 F).
1955 – Coldest year of Seattle-Tacoma History (48.0 F). Spectacular temperature plunge and ensuing six-day cold spell in early November.
1953 – January wettest calendar month (12.92″) until November 2006.
1952 – Driest calendar year in history (23.78″); also driest Fall (Sep-Nov) – 2.72″.
1950  – January coldest calendar month in history (24.9 F); 0 F on 31st; 53.3″ of snow recorded in month.  Also wettest calendar year in history (55.14″).
1949 – First seven weeks of year very cold with nearly 20″ snow.