On May 5th 2004, Canterbury experienced a day of stormy weather with unusual clouds, hail showers and thunder with lightning. A cold front passed over South-East England, undercutting the slower moving warm air mass and forcing it to rise. This resulted in the development of tall, rising cumulonimbus storm clouds, often accompanied by heavy rain.
A timetable of the days' weather has been created below with relevant photographs.

8:40am

After heavy showers overnight, large cumunlonimbus clouds were still present accompanied by unusual mammatus cloud.

Current temperature

8°C

Precipitation (last 24hrs)

14.3mm

Pressure

974mb; Falling

Cloud cover

4 oktas

Cloud Types

Cumulonimbus, cirrocumulus and mammatus

Wind Direction

Southerly
Mammatus cloud hanging from cumulonimbus formation

Anvil shaped cumulonimbus

Towering cumulonimbus

 

10am

By 10 o'clock, the cumulonimbus clouds began to darken and rain looked likely.
Despite such dark clouds, no precipitation fell.

 

10:30am

Mid-morning saw the darkest cumulonimbus clouds moving away and more blue sky was visible.

Dark cumulonimbus cloud moving away
More clear sky becoming visible as cumulonimbus clouds grow taller


11am

By 11:15, towering cumulonimbus clouds darkened again resulting in heavy and moderate rain showers.
Large cumulonibus clouds over the centre
Heavy and moderate rain showers fell for 12 minutes

 

12 noon

Over lunch we expereinced some heavy rain showers, torrential at times. At 12:50 we had a 10 minute hail shower. This was accompanied by one rumble of thunder and a flash of lightning.
Large cumulonimbus clouds darken and dominate the sky
Hail stones upto half a centimeter in diameter fell

 

1pm - 3pm
During the afternoon there was no more hail or rain showers. Cumulonimbus clouds were still present, though they had lost some height. These eventually broke down into smaller cumulus formations.