Graphical Climatology of Helsinki, Finland: Daily Temperatures and Rainfall, by Year (1959 – 2024)

The following is a graphical climatology of  Helsinki, Finland (Vantaa station) temperatures and precipitation, from 1959 into 2023.  Included are summary overview charts followed by 65 year-to-year graphs depicting daily temperatures, temperature anomalies, precipitation, and snow depths.  The temperature and precipitation data are converted from metric units to (rounded) degrees F, and inches, respectively; the snowdepths from cm to inches. 

Source is the Finnish Meteorological Institute climate statistics site:

https://en.ilmatieteenlaitos.fi/climate-statistics 

In addition to the daily temperature and precipitation variations of selected parameters on single-page grid-layouts analogous to topographic maps. These are derived from downloaded raw hourly observational data from the NOAA NCDC’s  “Access to Global Hourly Surface Data” online site:

https://www.ncei.noaa.gov/access/search/data-search/global-hourly

Author: Charles Fisk    e-mail contact:  cjfisk@att.net

Latest update: 22 Jun 2024 

CLIMATE OVERVIEW GRAPHS

Helsinki Daily Temperatures and Precipitation for 2024   New (6/22/24)
Helsinki Daily Temperatures and Precipitation for 2023  
Helsinki Daily Temperatures and Precipitation for 2022
Helsinki Daily Temperatures and Precipitation for 2021   
Helsinki Daily Temperatures and Precipitation for 2020 
Helsinki Daily Temperatures and Precipitation for 2019

HELSINKI MISCELLANEOUS
CLIMATOLOGICAL RAINFALL, SNOWFALL, AND TEMPERATURE GRAPHS

• Helsinki Annual Precipitation History  (1959-2022)    
• Helsinki Annual Mean Temperature History  (1959-2022)
• Helsinki # of Days with Snowcover, by Season 
• Helsinki # of Days with 12″ or greater Snowcover, by Season 
• Helsinki Temps at One-Third Month Intervals   
• Helsinki Mean Monthly Precipitation
• Helsinki Pct. Frequencies of >=0.01 in., >=0.10 in., >= 0.25 in, >=0.50 and >=1.00 in. Rainfall Days, by Calendar Day (1959-2020) 
• Helsinki Mean Daily Temperature Range, by Calendar Day

HOUR-BY-MONTH CLIMOGRAMS FOR HELSINKI

• Mean & Extreme Hourly Temps (Upper 99th & and Lower 1st Percentile Levels)
• Mean Hourly Rel Hum’s
• Lowermost 1st percentile (dry) Rel Hum’s  
• Mean Vector Wind Directions, Speeds, and Constancies
• Prevailing 8-Point Compass Wind Directions, Frequencies, and Mean Speeds
• Mean Scalar Wind Speeds
• Extreme Highest Sustained Winds (99% Percentile Level)
• Cloud Ceilings
• Fog
• Thunderstorms

YEAR-TO-YEAR GRAPHS – INTERPRETATION

The uppermost chart for a given year’s page, accessed by the links below, are “floating-bars” of the year’s daily maxima and minima temperatures (in deg F).  The bars depict the varying diurnal, synoptic, long-wave, and seasonal temperature anomaly influences on Helsinki temperature over the course of the year, and for effect, the bars are merged together to create a  signature-like appearance.

     The second chart down shows the day-to-day mean temperature anomalies (daily mean temperature less the corresponding long-term 1959-2020 climatological mean),  and the third one, the anomalies in deseasonalized or standardized form (z-scores). Greatest positive standardized departure in the 1959-2020 Helsinki record is +3.20 z for 8 Aug 2010, greatest negative –4.34 z for 17 Apr 1966.  

    The fourth chart down depicts daily precipitation totals, as high as 2.58 inches (9 Jul 1996), the the fifth, daily snowdepths, as high as 34.6″ on five different days in February 1966.

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

SELECTED YEARS’ WITH SOME OF THE MORE INTERESTING PATTERNS

2020 – Warmest AND Wettest Year in history – ’19-’20 Snow Season also the  lightest in history.  
2015 – Warmest Year to date (45.1 F). No subzero temperatures all year (lowest +2 F).
2014 – Gyrating temperature anomaly spells, both warm and cold  over first half of year.
2011 – Another snowy (’10-’11) winter. Cold February, but warmest Summer AND Fall to date.
2010 – Snowiest 2009-2010 winter season since 1969-1970, but warmest calendar month (July) of history (72.7 F); also warmest Summer to date; 93 F on 28 July.  Max/Min on 8 August: 89 F/71 F).
2008 – Warmest Year to date (44.7 F). January and February each warmer than March.
2006 – Driest Summer (June-August: 2.76″ precipitation). 
2002 – Persistent well above average daily temperatures thru early September, abrupt shift to colder than average thru year-end.
2000 – Warmest year to date (44.2 F).
1994 –  First 90 F + of post-1959 period, on 27-July.
1989  – Mildest January to March period on record (32.8 F), and warmest year of at least the last 30 – (43.5 F).  Commences warming trend in annual mean temperatures: 26 of next 32 years including ’89 warmer than 1959-2020 mean (41.4 F). 
1987 – Historic cold spell in January. Temperatures no higher than -12 F over the 5th to 12th,  -20 F over the 9th to 12th. Daily mean departures as great as -51 F. Monthly mean only 0.5 F – Coldest calendar month in history, post-1959.
1985 – Very Cold January & February. Coldest Year of 1959-present period (36.8 F).
1978  – Intense cold closes the year. Coldest December of 1959-present period (9.0 F) and coldest year thus far overall (37.3 F).
1976 –  Driest Year (16.63″) of 1959- Present period.
1974 – Record Wet Fall (Sep.-Nov. – 14.66″). No subzero temperatures during the year (minimum: + 6 F).
1973 – Cold spells, progressively more anomalous,  from mid-August on.
1966 – Long cold winter. Continuous snow cover from 17 Nov ’65 thru 30 Apr ’66.  Temperature drops to 3 F on 17 April; ’65-’66 snow season the heaviest in history.
1965 – Pronounced cold spells, usually several weeks’ duration, throughout the year.