Monthly Climate Summary for  January 2009  at Luton (Cranleigh Gardens)
                          home daily
                     Coldest since 1997;  very dry first half then frequent outbreaks of rain;  quite bright     back forward
                         
Overall mean temperature was 2.3 ēC which is -1.7 degC compared with the 1971-2000 average  
Mean day maximum (09-21) was 4.7 ēC which is -1.7 degC compared with the 1971-2000 average  
Mean night minimum (21-09) was 0.0 ēC which is -1.7 degC compared with the 1971-2000 average  
Mean 24hr maximum (09-09) was 5.2 ēC                
Mean 24hr minimum (09-09) was -0.8 ēC                
  Highest day max was 9.0 ēC on  the   12                 
  Lowest day max was -1.3 ēC on  the 6            
  Highest night min was 7.5 ēC on  the 12            
  Lowest night min was -9.6 ēC on  the 6            
  Lowest grass min was -15.7 ēC on  the 6            
                         
Total rainfall this month was 59.2 mm which is 86.9 per  cent of the 1971-2000 average    
  Highest daily fall was 11.7 mm on  the 21            
Number of hours with rain was                    
Equiv. TSR rainfall duration was 53.8 hrs which is 78.9 per  cent of the 1971-2000 average    
  Highest no of wet hrs   hrs on  the              
  Highest duration 10.0 hrs on  the 6            
  Mean rainfall intensity 1.10 mm/hr                
                         
Total CS sunshine this month was 58.6 hrs which is 111.4 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 6.0 hrs on  the 6            
                         
Maximum  snow depth  was 3.0 cm on  the  4            
                         
Mean sea-level pressure at 09Z 1011.8 mbar which is -2.8 mbar compared with the 1961-1990 average  
  Highest pressure at 09Z 1032.6 mbar on  the 3            
  Lowest  pressure at 09Z 970.8 mbar on  the 23            
                         
Number of days with:                      
Air Frost 15   0.2mm rain 15   No  sun 9   Snow lying 5    
Grnd Frost 22   1.0mm 12   3h  sun 10   Snow/sleet 2    
Max < 0ēC 4   5mm 6   6h  sun 1   Hail 0    
Max > 10 0   10mm 1   9h  sun 0   Thunder 0    
Max > 20 0   25mm 0   12h sun 0   Fog at 09Z 4    
Max > 30 0         15h sun 0   Gale 0    
                         
Notable events during the month: