Monthly Climate Summary for December 2004 at Luton (Cranleigh Gardens)
                          home daily
                                      Dull but dry first half;  much sunnier second half. Cold bright Christmas     back forward
                         
Overall mean temperature was 5.0 ēC which is +0.1 degC compared with the 1971-2000 average  
Mean day maximum (09-21) was 7.4 ēC which is +0.3 degC compared with the 1971-2000 average  
Mean night minimum (21-09) was 2.6 ēC which is -0.1 degC compared with the 1971-2000 average  
Mean 24hr maximum (09-09) was 7.8 ēC                
Mean 24hr minimum (09-09) was 2.1 ēC                
  Highest day max was 12.0 ēC on  the   23                 
  Lowest day max was 2.6 ēC on  the 13            
  Highest night min was 9.1 ēC on  the 23            
  Lowest night min was -4.8 ēC on  the 27            
  Lowest grass min was -9.7 ēC on  the 26            
                         
Total rainfall this month was 34.4 mm which is 50.8 per  cent of the 1971-2000 average    
  Highest daily fall was 10.1 mm on  the 21            
Number of hours with rain was                    
Equiv. TSR rainfall duration was 28.4 hrs which is 45.7 per  cent of the 1971-2000 average    
  Highest no of wet hrs   hrs on  the              
  Highest duration 7.0 hrs on  the 28            
  Mean rainfall intensity 1.21 mm/hr                
                         
Total CS sunshine this month was 51.3 hrs which is 105.8 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 6.5 hrs on  the 28            
                         
Maximum  snow depth  was 0.0 cm on  the  19            
                         
Mean sea-level pressure at 09Z 1018.5 mbar which is +3.9 mbar compared with the 1961-1990 average  
  Highest pressure at 09Z 1032.0 mbar on  the 8            
  Lowest  pressure at 09Z 991.7 mbar on  the 17            
                         
Number of days with:                      
Air Frost 6   0.2mm rain 13   No  sun 6   Snow lying 0    
Grnd Frost 22   1.0mm 6   3h  sun 6   Snow/sleet 0    
Max < 0ēC 0   5mm 3   6h  sun 2   Hail 0    
Max > 10 8   10mm 1   9h  sun 0   Thunder 0    
Max > 20 0   25mm 0   12h sun 0   Fog at 09Z 2    
Max > 30 0         15h sun 0   Gale 0    
                         
Notable events during the month:                  
Sunshine for 1st-15th was 12.7h,  but for 16th-31st it was 38.6h              
Rainfall  for the 1st-15th was 1.7mm, for the 16th-31st it was 32.7mm              
Coldest Christmas Day (overall mean) for eight years;  sunniest Dec 26 since before 1954