January is statistically the coldest month for Europe and 1985 was one of the coldest on record.
By Federico Fierli and Mark Higgins (EUMETSAT)
January 1985 was extremely cold and snowy for the whole of Europe and US. After a warm December, cold air hit central and southern Europe during Christmas, bringing severe snowfall to many southern European cities from 5 January.
This phase was the start of a prolonged cold wave in Europe, with extremely low temperatures, the lowest on record, and unusually high precipitation, especially in northern Italy. The weather systems that passed over Italy between 6-9 January led to an almost complete coverage of snow across the country. Close to Milan, after fours days of snow, 120 cm was recorded. In Florence the minimum low was -20 °C.
In France the coldest ever temperature of -41 °C was recorded in Doubs on 17 January. In Serbia the lowest ever minimum of -39.5 °C was recorded at Karajukića Bunari on 13 January. Across Europe several deaths were reported due to the event, and schools and airports were shut down for several days.
The Meteosat-2 image (Figure 1, top right, click to expand) shows how Europe woke up under a white snow blanket on the morning of 6 January. Figure 2 shows the weather system from 4 to 12 January.
Figure 2: Meteosat-2 visible animation, 4 January 12:00 UTC–12 January 12:00 UTC
In the US, January 1985 was the coldest January on record, with record low temperatures all around the country. In Chicago, a record low of −33 °C, combined with 40 km/h winds produced a a wind chill of −61 °C on 20 January. Pittsburgh had a low of −28 °C, the coldest morning since 1899. On 21 January Mount Mitchell in North Carolina recorded a low of -37 °C. There were a reported 30 deaths and severe damage to a lot of crops. Even the traditional parade of the public inauguration of the President (Reagan), was cancelled due to cold weather.
On the global temperature anomaly pattern for January 1985 (Figure 3), a cold dipole can be clearly seen above Europe and the US, with an unusually high temperature (up to 5 °C) above the Arctic.
We now know that these events are facets of the same meteorological phenomenon. Research found that such a pattern was the effect of a Sudden Stratospheric Warming occurring in December 1984 — described in this paper from 1986
This weather scenario also characterised recent European cold spells, such as the one in February 2018.
Six inches of snow, followed by a Roman Holiday (New York Times)
January 1985 Record-breaking Cold (NOAA/NWS)
34 years ago the snowfall of the century (MeteoSwiss, in Italian)
Warm Arctic episodes linked with increased frequency of extreme winter weather in the United States (Nature)
Previous case studies
How satellites help predict a Sudden Stratospheric Warming (SSW) (16 January 2013)