Very cold and Snowy
Temperatures
The average maximum temperature during January 2021 in Horsholm was 2.3 Celsius, and that was around 2 degrees below normal for the time of year. The average minimum temperature was -1.7 Celsius, and that was also close to 2 degrees below the December normal.
The highest temperature recorded during the month was 8.1 Celsius on the 21st, but there were only 2 other days with maxima above 5 Celsius. They were the 20th and 22nd, with highs of 6.3 and 6.8 Celsius respectively. A further 5 days had temperatures above 3 Celsius, with the mildest weather generally occurring in the fourth week of January. On many days (11), the highest temperature was between 1 and 2 Celsius, but on 6 days it was colder. On 2 days the maximum temperature was below minus 1 Celsius, with minus 1.7 Celsius recorded on the 15th, and minus 1.5 measured on the 29th.
There was almost a complete lack of mild nights during January. The mildest night between the 1st and 19th was only the 1.1 Celsius that occurred on the 11th. The 3 consecutive days 20th, 21st and 22nd were slightly less cold with minima of 2.2, 4.7 and 2.3 Celsius respectively. In fact, out of the 7 nights beginning on the 19th, only the 23rd, with a low of minus 0.5 Celsius, had a minimum below freezing. The lowest temperatures occurred around the middle and end of the month, and on 6 occasions the minimum was below minus 5 Celsius. Minus 8.7 Celsius was recorded on the 16th and minus 7.9 Celsius was measured on the 30th.
Frost
January had 22 air frosts, and that was around 9 above the average. A total of 15 of the first 18 nights had frost, but it was often slight, with 10 nights having a minimum temperature between zero and minus 1 Celsius. After some milder nights, the last 6 in January had minima below minus 2 Celsius.
Rain
There were 54.2 millimetres of rain recorded during January, and that was over 20% above the average. Measurable precipitation fell on 19 days, and that was 1 day below average, and wet days (when 1 millimetre or more of rain was measured) numbered 15 days, and that was average for the month. Apart from 2.2 millimetres of rain on the 1st, precipitation during the first 18 days was either sleet or snow. On most days, the total was below 3 millimetres, but 5.8 millimetres were recorded on the 7th, over 6 millimetres fell on the 10th, and 4.8 millimetres were measured on the 13th. Rain fell on the 20th and amounted to 10.2 millimetres, with further rain on the 22nd adding 5 millimetres to the total. Precipitation during the rest of the month was either sleet or snow, with no daily totals above 2 millimetres.
Hail
No hail was observed in this part of Horsholm.
Thunder
No thunder was heard in this part of Horsholm.
Snow
Sleet or snow fell on 12 days during January, with the second and last weeks of the month being particularly snowy. No large amounts accumulated, but the ground was more than half covered with snow on 19 mornings. On most days 1 or 2 centimetres were recorded, but on the 6th a depth of 3 centimetres was measured, with 4 centimetres lying on the 8th.
Wind
Despite the cold weather, southwesterly winds were again dominant in January and accounted for around a third of the daily observations. This was closely followed by northwesterly winds, with those from the southeast trailing some way behind. The wind was mostly gentle or moderate, but on the 2nd it was flat calm all day. Some stronger southwesterly winds occurred during the second week, and a strong southeasterly breeze blew on the 21st.
Fog
There was thick fog on the morning of the 2nd.