Monthly Climate Summary for September 2011 at Luton (Cranleigh Gardens)
                          home daily
Rather changeable with near-normal temperature for most of the month; notably warm sunny ending back forward
                         
Overall mean temperature was 16.0 C which is +2.0 degC compared with the 1971-2000 average  
Mean day maximum (09-21) was 20.7 C which is +2.3 degC compared with the 1971-2000 average  
Mean night minimum (21-09) was 11.4 C which is +1.7 degC compared with the 1971-2000 average  
Mean 24hr maximum (09-09) was 20.7 C                
Mean 24hr minimum (09-09) was 11.4 C                
  Highest day max was 27.6 C on the 30            
  Lowest day max was 15.5 C on the 18            
  Highest night min was 15.4 C on the 10            
  Lowest night min was 5.5 C on the 15            
  Lowest grass min was 3.2 C on the 15            
                         
Total rainfall this month was 46.8 mm which is 73.0 per cent of the 1971-2000 average    
  Highest daily fall was 20.6 mm on the 4            
Number of hours with rain was                    
TSR rainfall duration was 28.8 hrs which is 70.8 per cent of the 1971-2000 average    
  Highest no of wet hrs   hrs on the              
  Highest duration 5.5 hrs on the 20            
  Mean rainfall intensity 1.63 mm/hr                
                         
Total CS sunshine this month was 145.0 hrs which is 106.2 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 10.7 hrs on the 1            
                         
Maximum snow depth was 0.0 cm on the              
                         
Mean sea-level pressure at 09Z 1013.5 mbar which is -2.9 mbar compared with the 1961-1990 average  
  Highest pressure at 09Z 1029.1 mbar on the 27            
  Lowest pressure at 09Z 999.3 mbar on the 12            
                         
Number of days with:                      
Air Frost 0   0.2mm rain 16   No sun 1   Snow lying 0    
Grnd Frost 0   1.0mm 8   3h sun 23   Snow/sleet 0    
Max < 0C 0   5mm 3   6h sun 11   Hail 0    
Max > 10 30   10mm 1   9h sun 2   Thunder 0    
Max > 20 16   25mm 0   12h sun 0   Fog at 09Z 0    
Max > 30 0         15h sun 0   Gale 0    
                         
Notable events during the month: