Air Temperature

Highest Maximum 20.4°C 5th
Lowest Maximum 13.5°C 27th
Highest Minimum 16.4°C 5rh 
Lowest Minimum 9.4°C 27th

 

Mean Maximum 17.5°C
Mean Minimum 12.8°C
Mean 15.2°C

 

Relative Humidity

Highest Relative Humidity 94% Several Days
Lowest Relative Humidity 49% 7th

 

Mean Relative Humidity 75.8%

 

Atmospheric Pressure

Highest Atmospheric Pressure 1028.8hPa 23rd
Lowest Atmospheric Pressure 999.7hPa 12th

 

Mean Atmospheric Pressure 1014.6hPa

 

Wind

Highest Gust 59.5km/h 13th

 

Mean Wind Speed 10.5km/h
Mean Gust Speed 21.5km/h
Mean Wind + Gust Speed 16.0km/h
Most Frequent Wind Direction Southwest

 

Precipitation

Total Rainfall During December 2020 94.1 mm
Total Rainfall Since Last 01/09 346.9 mm

 

Highest 24 Hour Total 20.6 mm 21st

 

Rain Days 15
Thunderstorm Days 7
Hail Days 5

 

Rainfall Events

02/12/2020 4.7 mm Showers
03/12/2020 6.9 mm Showers; Distant Thunder
04/12/2020 0.3 mm Light Rain
06/12/2020 2.9 mm Showers; Distant Thunder; Hail
07/12/2020 1.4 mm Showers
09/12/2020 3.6 mm Light Rain; Thundery Rain/Hail Shower
10/12/2020 0.7 mm Light Rain
11/12/2020 8.0 mm Showers
12/12/2020 16.0 mm Thundery Rain/Hail Showers
13/12/2020 1.3 mm Shower
19/12/2020 6.9 mm Thunderstorm
20/12/2020 6.8 mm Showers; Distant Thunder
21/12/2020 20.6 mm Thunderstorm with Hail
26/12/2020 1.7 mm Isolated Shower
27/12/2020 12.3 mm Blustery Rain/Hail Showers

 

December 2020 Compared to the Climate Means

  Climate Mean December 2020 Anomaly
Mean Maximum Temperature 16.9°C 17.5°C +0.6°C
Mean Minimum Temperature 11.7°C 12.8°C +1.1°C
Mean Temperature 14.3°C 15.2°C +0.9°C
Mean Relative Humidity 79% 75.8% -3.2%
Mean Atmospheric Pressure 1017.3hPa 1014.6hPa -2.7hPa
Mean Wind Speed 18.2 km/h 16.0 km/h -2.2km/h
Most Frequent Wind Direction Northwest Southwest -45°
Total Rainfall 97.1 mm 94.1 mm -3 mm
Total Rainfall Since Last 01/09 326.1 mm 346.9 mm +20.8 mm
Total Rain Days 13 15 +2
Total Thunderstorm Days 4 7 +3
Total Hail Days 1 5 +4

 

Warmer December 2020

December’s air temperature peaked on the 5th, with a daytime high of 20.4°C and a nighttime low of 16.4°C. Conversely, with a daytime high of 13.5°C and a nighttime low of 9.4°C, the 27th was last month’s coolest day. The 27th was one of only two days with a minimum temperature below 10°C, as the Maltese Islands missed out on a cold snap that is normally experienced around Christmas. Overall, December 2020 was warmer than normal. The mean temperature of 15.2°C was almost a full degree above the climate mean.

The month of December 2020 maintained the trend set in the second half of November. Rain came in frequent showery episodes and was evenly distributed over the whole month. With a 24 hour total of 20.6 mm, the first day of winter (the 21st) was the wettest. A total of 94.1 mm of rain was measure in Għarb last month. This value falls just a few millimetres short of the climate average. This puts rainfall in Għarb at 346.9 mm since last September 1st, a good 20.8 mm higher than the norm. We had rain on 15 days last December. Thunder was heard on 7 of these, whilst hail accompanied the rain on 5 of these.

The month was generally calmer than the norm, maintaining a mean wind speed of 16.0 km/h rather than the expected 18.2 km/h. Whilst windy days were not lacking, the abscence of any extremely strong gales contributed to the lower mean wind speed. The wind reached Force 7 (50km/h) or stronger on 7 occasions. It reached Force 8 (62km/h) on one of these. Winds from the Southwest were characteristic of December 2020. A Southwest wind advects warm and moist air from the south across the central Mediterranean. This attributed to the significantly warmer than average temperatures experienced over the course of last month. It was also the chief cause behind the frequent showery episodes experienced. The persistent availability of warm and moist air around the Maltese Islands helped generate instability whenever cold air aloft reached our region from the north.

 

 

Rainfall Totals around the Maltese Islands in December 2020 (and since last September 1st)

Għarb – 94.1 mm (346.9 mm)

Victoria – 82.6 mm (327.4 mm)

Xewkija – 68.0 mm (261.8 mm)

Nadur – 98.4 mm (388.2 mm)

Mellieħa – 56.2 mm (211.2 mm)

Buġibba – 70.0 mm (233.3 mm)

Mġarr – 62.2 mm (208.9 mm)

Għargħur – 56.3 mm (302.3 mm)

Attard – 69.3 mm (375.8 mm)

Rabat – 67.8 mm (207.1 mm)

Msida – 81.6 mm (316.7 mm)

Valletta – 55.8 mm (200.2 mm)

Luqa – 68.2 mm (326.6 mm)

Żabbar – 85.6 mm (340.9 mm)

Birżebbuġa – 51.1 mm (237.3 mm)