Monthly Climate Summary for December 2008 at Chesham (Tennis Club)
                          home daily
              Rather cold first half, and again during the last week. Dry second half       back forward
                         
Overall mean temperature was 3.7 ēC which is   degC compared with the 1971-2000 average  
Mean day maximum (09-21) was 6.5 ēC which is   degC compared with the 1971-2000 average  
Mean night minimum (21-09) was 1.0 ēC which is   degC compared with the 1971-2000 average  
Mean 24hr maximum (09-09) was 6.5 ēC                
Mean 24hr minimum (09-09) was 0.2 ēC                
  Highest day max was 12.7 ēC on  the   20            
  Lowest day max was 0.2 ēC on  the 31            
  Highest night min was 9.8 ēC on  the 22            
  Lowest night min was -6.6 ēC on  the 31            
  Lowest grass min was   ēC on  the              
                         
Total rainfall this month was 40.6 mm which is   per  cent of the 1971-2000 average    
  Highest daily fall was 23.2 mm on  the 13            
Number of hours with rain was                    
Equiv. TSR rainfall duration was 8.0 hrs which is   per  cent of the 1971-2000 average    
  Highest no of wet hrs   hrs on  the              
  Highest duration 2.8 hrs on  the 3            
  Mean rainfall intensity 5.08 mm/hr                
                         
Total est sunshine this month was 8.0 hrs which is   per  cent of the 1971-2000 average    
Equiv. C/S sunshine total was   hrs which is   per  cent of the 1971-2000 average    
  Highest daily sun was 1.3 hrs on  the 3            
                         
Maximum  snow depth  was 0.0 cm on  the               
                         
Mean sea-level pressure at 09Z 1018.5 mbar which is   mbar compared with the 1961-1990 average  
  Highest pressure at 09Z 1037.9 mbar on  the 26            
  Lowest  pressure at 09Z 978.7 mbar on  the 4            
                         
Total number of days with:                      
Air Frost 12   0.2mm rain 13   No  sun 16   Snow lying 0    
Grnd Frost 0   1.0mm 7   3h  sun 0   Snow/sleet 0    
Max < 0ēC 0   5mm 2   6h  sun 0   Hail 0    
Max > 10 4   10mm 1   9h  sun 0   Thunder 0    
Max > 20 0   25mm 0   12h sun 0   Fog at 09Z 0    
Max > 30 0         15h sun 0   Gale 0    
                         
Notable events during the month: