| Monthly Climate Summary for May 2004 at Luton (Cranleigh Gardens) | ||||||||||||||
| home | daily | |||||||||||||
| Wet first week; fine and warm mid-month; changeable end | back | forward | ||||||||||||
| Overall mean temperature was | 12.7 | ēC | which is | +1.1 | degC | compared with the 1971-2000 average | ||||||||
| Mean day maximum (09-21) was | 17.6 | ēC | which is | +1.1 | degC | compared with the 1971-2000 average | ||||||||
| Mean night minimum (21-09) was | 7.8 | ēC | which is | +1.1 | degC | compared with the 1971-2000 average | ||||||||
| Mean 24hr maximum (09-09) was | 17.6 | ēC | ||||||||||||
| Mean 24hr minimum (09-09) was | 7.8 | ēC | ||||||||||||
| Highest day max was | 23.8 | ēC | on the | 17 | ||||||||||
| Lowest day max was | 11.9 | ēC | on the | 1 | ||||||||||
| Highest night min was | 12.5 | ēC | on the | 29 | ||||||||||
| Lowest night min was | 1.4 | ēC | on the | 22 | ||||||||||
| Lowest grass min was | -0.4 | ēC | on the | 22 | ||||||||||
| Total rainfall this month was | 58.5 | mm | which is | 110.0 | per cent | of the 1971-2000 average | ||||||||
| Highest daily fall was | 17.6 | mm | on the | 3 | ||||||||||
| Number of hours with rain was | ||||||||||||||
| Equiv. TSR rainfall duration was | 40.1 | hrs | which is | 93.6 | per cent | of the 1971-2000 average | ||||||||
| Highest no of wet hrs | hrs | on the | ||||||||||||
| Highest duration | 12.5 | hrs | on the | 7 | ||||||||||
| Mean rainfall intensity | 1.46 | mm/hr | ||||||||||||
| Total CS sunshine this month was | 176.4 | hrs | which is | 95.5 | 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 | 13.1 | hrs | on the | 22 | ||||||||||
| Maximum snow depth was | 0.0 | cm | on the | |||||||||||
| Mean sea-level pressure at 09Z | 1016.6 | mbar | which is | +1.5 | mbar | compared with the 1961-1990 average | ||||||||
| Highest pressure at 09Z | 1031.2 | mbar | on the | 16 | ||||||||||
| Lowest pressure at 09Z | 978.8 | mbar | on the | 5 | ||||||||||
| Number of days with: | ||||||||||||||
| Air Frost | 0 | 0.2mm rain | 12 | No sun | 2 | Snow lying | 0 | |||||||
| Grnd Frost | 2 | 1.0mm | 8 | 3h sun | 23 | Snow/sleet | 0 | |||||||
| Max < 0ēC | 0 | 5mm | 4 | 6h sun | 13 | Hail | 1 | |||||||
| Max > 10 | 31 | 10mm | 2 | 9h sun | 7 | Thunder | 0 | |||||||
| Max > 20 | 11 | 25mm | 0 | 12h sun | 2 | Fog at 09Z | 1 | |||||||
| Max > 30 | 0 | 15h sun | 0 | Gale | 0 | |||||||||
| Notable events during the month: | ||||||||||||||
| 4th: Barometer fell to 976mbar - exceptionally low for May | ||||||||||||||
| Remarkable lack of sunshine during the first two weeks with just 39.4h (48% of norm) -- previous lowest 47.3h in 1978 | ||||||||||||||
| Total rainfall during the 22 days 9th-30th was just 5.2mm | ||||||||||||||