Climate of Iceland
The climate of Iceland is subpolar oceanic (Köppen climate classification Cfc)[1] near the southern coastal area and tundra (Köppen ET) inland in the highlands. The island lies in the path of the North Atlantic Current, which makes its climate more temperate than would be expected for its latitude just south of the Arctic Circle. This effect is aided by the Irminger Current, which also helps to moderate the island's temperature.[2] The weather in Iceland is notoriously variable.[3]
The aurora borealis is often visible at night during the winter. The midnight sun can be experienced in summer on the island of Grímsey off the north coast; the remainder of the country, since it lies just south of the polar circle, experiences a twilight period during which the sun sets briefly, but still has around two weeks of continuous daylight during the summer.
Seasons
Winter
The Icelandic winter is relatively mild for its latitude, owing to maritime influence and proximity to the warm currents of the North Atlantic Gyre. The southerly lowlands of the island average around 0 °C (32 °F) in winter, while the north averages around −10 °C (14 °F). The lowest temperatures in the northern part of the island range from around −25 to −30 °C (−13 to −22 °F). The lowest temperature on record is −39.7 °C (−39.5 °F).[4]
Summer
The average July temperature in the southern part of the island is 10–13 °C (50–55 °F). Warm summer days can reach 20–25 °C (68–77 °F).[4] The highest temperature recorded was 30.5 °C (86.9 °F) in the Eastern fjords in 1939. Annual average sunshine hours in Reykjavík are around 1300, which is similar to towns in Scotland and Ireland.[5]
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Record high °C (°F) | 11.6 (52.9) |
10.2 (50.4) |
14.2 (57.6) |
17.1 (62.8) |
20.6 (69.1) |
22.4 (72.3) |
25.7 (78.3) |
24.8 (76.6) |
20.1 (68.2) |
15.7 (60.3) |
12.7 (54.9) |
12.0 (53.6) |
25.7 (78.3) |
| Mean daily maximum °C (°F) | 3.2 (37.8) |
3.3 (37.9) |
4.2 (39.6) |
6.9 (44.4) |
10.1 (50.2) |
13.0 (55.4) |
14.9 (58.8) |
14.1 (57.4) |
11.4 (52.5) |
7.6 (45.7) |
4.7 (40.5) |
3.3 (37.9) |
8.1 (46.6) |
| Daily mean °C (°F) | 0.7 (33.3) |
0.5 (32.9) |
1.2 (34.2) |
3.7 (38.7) |
6.7 (44.1) |
9.8 (49.6) |
11.6 (52.9) |
11.0 (51.8) |
8.5 (47.3) |
4.9 (40.8) |
2.2 (36.0) |
0.8 (33.4) |
5.1 (41.2) |
| Mean daily minimum °C (°F) | −1.7 (28.9) |
−1.9 (28.6) |
−1.3 (29.7) |
1.0 (33.8) |
4.0 (39.2) |
7.2 (45.0) |
9.1 (48.4) |
8.6 (47.5) |
6.2 (43.2) |
2.7 (36.9) |
−0.1 (31.8) |
−1.6 (29.1) |
2.7 (36.9) |
| Record low °C (°F) | −24.5 (−12.1) |
−17.6 (0.3) |
−16.4 (2.5) |
−16.4 (2.5) |
−7.7 (18.1) |
−0.7 (30.7) |
1.4 (34.5) |
−0.4 (31.3) |
−4.4 (24.1) |
−10.6 (12.9) |
−15.1 (4.8) |
−16.8 (1.8) |
−24.5 (−12.1) |
| Average precipitation mm (inches) | 87.1 (3.43) |
90.6 (3.57) |
80.7 (3.18) |
59.0 (2.32) |
52.6 (2.07) |
43.3 (1.70) |
49.9 (1.96) |
64.5 (2.54) |
87.0 (3.43) |
79.8 (3.14) |
86.5 (3.41) |
94.9 (3.74) |
875.9 (34.48) |
| Average snowfall cm (inches) | 19.9 (7.8) |
17.1 (6.7) |
23.2 (9.1) |
12.1 (4.8) |
1.6 (0.6) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
1.4 (0.6) |
8.7 (3.4) |
17.8 (7.0) |
101.8 (40.1) |
| Average precipitation days (≥ 1.0 mm) | 15.3 | 15.0 | 14.2 | 12.0 | 10.8 | 9.3 | 10.3 | 11.6 | 15.0 | 13.1 | 13.7 | 14.6 | 154.9 |
| Average snowy days (≥ 0 cm) | 12.2 | 12.4 | 9.6 | 2.1 | 0.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.6 | 5.3 | 12.6 | 55.1 |
| Average relative humidity (%) | 78.1 | 77.1 | 76.2 | 74.4 | 74.9 | 77.9 | 80.3 | 81.6 | 79.0 | 78.0 | 77.7 | 77.7 | 77.8 |
| Average dew point °C (°F) | −2.9 (26.8) |
−3.3 (26.1) |
−3.0 (26.6) |
−1.0 (30.2) |
2.0 (35.6) |
5.6 (42.1) |
7.9 (46.2) |
7.6 (45.7) |
5.1 (41.2) |
1.2 (34.2) |
−1.5 (29.3) |
−2.9 (26.8) |
1.2 (34.2) |
| Mean monthly sunshine hours | 22.6 | 61.6 | 110.3 | 165.1 | 209.0 | 189.5 | 183.1 | 164.8 | 118.3 | 91.6 | 39.7 | 12.6 | 1,368.2 |
| Percent possible sunshine | 12 | 25 | 29 | 36 | 35 | 28 | 28 | 31 | 31 | 31 | 21 | 16 | 27 |
| Average ultraviolet index | 0 | 0 | 1 | 2 | 3 | 4 | 4 | 3 | 2 | 1 | 0 | 0 | 2 |
| Source 1: Icelandic Met Office,[6][7][8] NOAA[9] | |||||||||||||
| Source 2: timeanddate.com (sunshine percent and dewpoints),[10] Weather Atlas, (UV)[11] and Meteo Climat[12] | |||||||||||||
| Climate data for Akureyri, 1991–2020 normals, extremes 1949–present | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 17.5 (63.5) |
14.5 (58.1) |
15.2 (59.4) |
21.5 (70.7) |
24.6 (76.3) |
29.4 (84.9) |
27.6 (81.7) |
27.7 (81.9) |
23.6 (74.5) |
19.5 (67.1) |
17.5 (63.5) |
15.1 (59.2) |
29.4 (84.9) |
| Mean daily maximum °C (°F) | 2.7 (36.9) |
2.6 (36.7) |
3.5 (38.3) |
6.6 (43.9) |
10.3 (50.5) |
13.7 (56.7) |
15.1 (59.2) |
14.8 (58.6) |
11.8 (53.2) |
6.6 (43.9) |
3.6 (38.5) |
2.6 (36.7) |
7.8 (46.0) |
| Daily mean °C (°F) | −0.5 (31.1) |
−0.8 (30.6) |
-0.0 (32.0) |
2.6 (36.7) |
6.2 (43.2) |
9.6 (49.3) |
11.2 (52.2) |
10.8 (51.4) |
8.0 (46.4) |
3.5 (38.3) |
0.6 (33.1) |
−0.7 (30.7) |
4.2 (39.6) |
| Mean daily minimum °C (°F) | −3.5 (25.7) |
−3.6 (25.5) |
−2.6 (27.3) |
−0.3 (31.5) |
3.2 (37.8) |
6.6 (43.9) |
8.5 (47.3) |
7.9 (46.2) |
5.4 (41.7) |
1.1 (34.0) |
−2.1 (28.2) |
−3.6 (25.5) |
1.4 (34.5) |
| Record low °C (°F) | −21.6 (−6.9) |
−21.2 (−6.2) |
−23.0 (−9.4) |
−18.2 (−0.8) |
−10.4 (13.3) |
−2.1 (28.2) |
1.3 (34.3) |
−2.2 (28.0) |
−8.4 (16.9) |
−13.6 (7.5) |
−18.5 (−1.3) |
−20.6 (−5.1) |
−23.0 (−9.4) |
| Average precipitation mm (inches) | 60.2 (2.37) |
52.2 (2.06) |
47.4 (1.87) |
25.9 (1.02) |
24.1 (0.95) |
20.7 (0.81) |
33.7 (1.33) |
41.4 (1.63) |
53.2 (2.09) |
74.0 (2.91) |
68.3 (2.69) |
72.8 (2.87) |
573.9 (22.59) |
| Average precipitation days (≥ 1.0 mm) | 11.1 | 10.2 | 9.9 | 6.7 | 5.9 | 4.9 | 7.7 | 8.1 | 9.4 | 11.7 | 10.9 | 12.0 | 108.5 |
| Average snowy days (≥ 0 cm) | 22.0 | 16.9 | 16.1 | 5.7 | 0.3 | 0.0 | 0.0 | 0.0 | 0.1 | 3.9 | 12.4 | 18.1 | 95.5 |
| Average relative humidity (%) | 79.4 | 79.3 | 78.9 | 75.7 | 73.4 | 73.2 | 77.8 | 78.3 | 77.4 | 81.2 | 80.8 | 79.5 | 77.9 |
| Average dew point °C (°F) | −3.8 (25.2) |
−4.2 (24.4) |
−3.7 (25.3) |
−1.9 (28.6) |
1.1 (34.0) |
4.7 (40.5) |
7.2 (45.0) |
6.9 (44.4) |
4.0 (39.2) |
0.2 (32.4) |
−2.5 (27.5) |
−3.9 (25.0) |
0.3 (32.6) |
| Mean monthly sunshine hours | 6.5 | 33.9 | 77.9 | 127.5 | 171.0 | 189.9 | 152.5 | 138.0 | 90.4 | 47.9 | 15.2 | 0.3 | 1,051 |
| Source 1: Icelandic Met Office (humidity 1981–2010)[13][14][15] | |||||||||||||
| Source 2: NOAA[16] | |||||||||||||
Winds and storms
Iceland, especially inland and during winter, is frequently subject to abrupt and dramatic changes in weather that can sharply reduce visibility, as well as rapidly increasing wind speed and precipitation, and shift temperature.
Generally, wind speeds tend to be higher in the highlands, but topographical features can aggravate winds and cause strong gusts in lowland areas. Wind speed in the lowlands reaches 18 m/s (40 mph) on 10–20 days per year, but on upwards of 50 days per year in places in the highlands.[4] The strongest measured 10-minute sustained wind speed is 62.5 m/s (140 mph) and the strongest gust 74.2 m/s (166 mph).[17] Heavy dust storms can be generated by strong glacial winds, and can be very strong. Up to 10 t (9.8 long tons; 11.0 short tons) of material can be in motion per transect per hour. These storms are very frequent in the early summer in the arid highland areas north of the Vatnajökull glacier.[18]
Thunderstorms are extremely rare for any specific location in Iceland, with fewer than five storms per year in the southern part of the island. They are most common in early or late summer. They can be caused by warm air masses coming up from Europe, or deep lows from the southwest in wintertime. Lightning can usually be observed in connection with ash plumes erupting from the island's volcanoes.[19] Vortices, sometimes on the scale of tornadoes, also occur with volcanic eruptions. Landspouts and waterspouts are occasionally observed. Classic mesocyclone derived tornadoes (i.e. forming from supercells) are very rare, but have been observed. Any of these do occasionally cause damage, although the sparse population further reduces the probability of detection and the hazard.[20][21]
Atmospheric pressure
There is a persistent area of low pressure near Iceland known as the Icelandic Low, found between Iceland and Greenland. This area affects the amount of air brought into the Arctic to the east, and the amount coming out of the Arctic to the west.[22] It is part of a greater pressure system known as the North Atlantic Oscillation (NAO).[23]
See also
References
- ^ "Koppen climate classification | climatology". Encyclopedia Britannica. Retrieved 2017-02-21.
- ^ "Climate in Iceland". notendur.hi.is. Retrieved 2017-02-21.
- ^ weatheronline.co.uk. "Climate of the World: Iceland | weatheronline.co.uk". www.weatheronline.co.uk. Retrieved 2017-02-21.
- ^ a b c "The dynamic climate of Iceland". University of Iceland.
- ^ "Sunrise and sunset times in Reykjavik". www.timeanddate.com. Retrieved 2017-02-21.
- ^ "Monthly Averages for Reykjavík". Icelandic Meteorological Office. Archived from the original on 2023-08-17. Retrieved 31 March 2020.
- ^ "Annual Averages for Reykjavík". Icelandic Met Office. Archived from the original on 2023-08-17. Retrieved 14 February 2016.
- ^ "Fréttir". Icelandic Meteorological Office. Archived from the original on 2023-08-17. Retrieved 12 August 2022.
- ^ "Reykjavik Climate Normals 1991-2020". National Oceanic and Atmospheric Administration. Archived from the original on 2023-08-17. Retrieved August 17, 2023.
- ^ "Reykjavík, Iceland – Sunrise, Sunset, and Daylength". timeanddate.com. Retrieved June 22, 2020.
- ^ "Monthly weather forecast and climate – Reykjavík, Iceland". Weather Atlas. Retrieved June 22, 2020.
- ^ "STATION REYKJAVIK". Meteo climat. Retrieved 11 June 2021.
- ^ "Monthly Averages for Akureyri". Icelandic Meteorological Office. Archived from the original on 2023-08-17. Retrieved 18 April 2019.
- ^ "Annual Averages for Akureyri". Icelandic Met Office. Archived from the original on 2023-08-17. Retrieved 18 April 2019.
- ^ "Akureyri 1961–1990 Averages". Icelandic Meteorological Office. Archived from the original on 2023-08-17. Retrieved 18 April 2019.
- ^ "Akureyri Climate Normals 1991-2020". National Oceanic and Atmospheric Administration. Archived from the original on 2023-08-17. Retrieved August 17, 2023.
- ^ "Icelandic weather records". Icelandic Met Office (in Icelandic). Retrieved 2017-03-20.
- ^ "Seasons and Climate | Iceland Travel | Weather in Iceland". Iceland Travel. Retrieved 2017-02-21.
- ^ "Iceland —". www.noonsite.com. Retrieved 2017-02-21.
- ^ Antonescu, Bogdan; D. M. Schultz; F. Lomas (2016). "Tornadoes in Europe: Synthesis of the Observational Datasets". Mon. Wea. Rev. 144 (7): 2445–2480. doi:10.1175/MWR-D-15-0298.1.
- ^ "Tornadoes leave South Iceland farm in ruins". Iceland Monitor. Reykjavík: Morgunblaðið. 27 August 2018. Retrieved 2019-02-10.
- ^ Hanna, Edward; Jónsson, Trausti; Box, Jason E. (2004-08-01). "An analysis of Icelandic climate since the nineteenth century". International Journal of Climatology. 24 (10): 1193–1210. doi:10.1002/joc.1051. ISSN 1097-0088.
- ^ "Climate Prediction Center - Teleconnections: North Atlantic Oscillation". www.cpc.ncep.noaa.gov. Retrieved 2017-02-21.
External links
- The dynamic climate of Iceland – A brief description of the country's climate (with maps)
- Reykjavík, Iceland Forecast: Weather Underground – Weather forecast for Reykjavík
