Doomsday by Warwick Deeping

A thunderstorm on an afternoon in May! Surely it was as unusual as it was unexpected?

She had dared Gore Wood a second time, and was sitting on the ash- grey stump of a felled oak in the midst of a pool of blueness. Wild violets looked at her from the dead oak leaves, scentless flowers, but the bluebells gave all the scent that was needed. A still, close air, and the perfume of the bells suffusing it. The leaf buds of the oaks were bronzing, and the hazels showed a yellowish green, and as the sky grew murky all these colours grew more vivid.