Heat builds! Technically now in a heatwave.

Tuesday saw the thermometer rise to 29.4XC, which was 8.3C above the average and the hottest day since 19th July (36.7C).

Overnight was cool with a low of 9.4C, which thankfully was 2.3C below the 38-year average so the new day started cool.

Wednesday brought strong sunshine from the start so at 08.00 the thermometer had recovered to 18.9C.

The Heatwave Threshold for Wiltshire is three consecutive days with maxima equal to or above 27C. The last three days gave us 27.1C, 29.1C and 29.4C respectively. During the last 10-year review five counties to the east of Wiltshire had their threshold temperature increased to 28C whereas the Wiltshire figure remained unchanged.

Update at 15.15: maximum of exactly 30.0C logged at 15.20, or 86F, up 0.6C on the Tuesday peak. Humidity of just 37% is very low.

Update at 17.00: peak temperature of 30.6C, or 87.1F, at 16.34. This was 9.5C above the long-term average.