Monthly Climate Summary for December 2010 at Hampstead  
                        home daily
                             Exceptionally cold until the 9th and 16th-27th;  several moderate snowfalls   back forward
                       
Overall mean temperature was 0.2 ēC which is -4.8 degC compared with the 1971-2000 average
Mean day maximum (09-21) was 2.3 ēC              
Mean night minimum (21-09) was -1.4 ēC              
Mean 24hr maximum (09-09) was 2.5 ēC which is -5.0 degC compared with the 1971-2000 average
Mean 24hr minimum (09-09) was -2.2 ēC which is -4.7 degC compared with the 1971-2000 average
  Highest day max was 7.9 ēC on  the   11          
  Lowest day max was -2.0 ēC on  the 3          
  Highest night min was 6.9 ēC on  the 29          
  Lowest night min was -6.1 ēC on  the 20          
  Lowest grass min was -13.0 ēC on  the 20          
                       
Total rainfall this month was 32.4 mm which is 49.1 per  cent of the 1971-2000 average  
  Highest daily fall was 7.5 mm on  the 18          
Number of hours with rain was 88.0 hrs              
Equiv. TSR rainfall duration was 61.6 hrs which is 108.1 per  cent of the 1971-2000 average  
  Highest no of wet hrs 14.0 hrs on  the 1          
  Highest equiv duration 11.6 hrs on  the 1          
                       
Total sunshine this month was 36.0 hrs which is 80.0 per  cent of the 1971-2000 average  
Equiv. C/S sunshine total was 39.6 hrs which is 80.0 per  cent of the 1971-2000 average  
  Highest daily sun was 5.8 hrs on  the 24          
                       
Maximum  snow depth  was 12.0 cm on the 19,21,22          
                       
Mean sea-level pressure at 09Z 1015.2 mbar which is +0.2 mbar compared with the 1961-1990 average
  Highest pressure at 09Z 1036.9 mbar on  the 15          
  Lowest  pressure at 09Z 992.7 mbar on  the 18          
                       
Number of days with:                    
Air Frost 25   0.2mm rain 17   No  sun 15   Snow lying 16  
Grnd Frost 26   1.0mm 10   3h  sun 6   Snow/sleet 9  
Max < 0ēC 10   5mm 2   6h  sun 0   Hail 0  
Max > 10 0   10mm 0   9h  sun 0   Thunder 0  
Max > 20 0   25mm 0   12h sun 0   Fog at 09Z 9  
Max > 30 0         15h sun 0   Gale 0  
                       
Notable events during the month: