The UK is on course to have its driest September since records began, according to provisional figures released on Tuesday by the Met Office.
The country received just 19.4mm of rain up to 28 September, about a fifth of the normal level.
It has also been one of the warmest Septembers in the past century.
But forecasters say the UK is set for a return to more normal conditions in early October - with cooler, wetter, and windier weather expected.
The Met Office holds rainfall records going back to 1910. Before this year, the driest September was in 1959, when 23.8 mm of rain fell.
Northern Ireland was the driest part of the UK with just 6.5mm of rain, a mere 7% of its average level.
Scotland was the wettest, experiencing 33.3mm of rain. Even that is the second driest Scottish September in the record books.
Forecaster Peter Sloss from the BBC Weather Centre said there was a probability of rain at the end of the month, but that it would be unlikely to stop the record being broken.
"There is some rain expected on Tuesday, which may alter the headline figures," he said. "But it will only have a marginal impact."
He said the dry spell had been caused by an area of high pressure which had dominated the UK's weather throughout September.
"It built up at the end of August and it just stayed put," he explained.
"The reason it stayed there was the jet stream, which diverted the areas of low pressure and the wetter weather towards Iceland."
The provisional figures from the Met Office also show that it has been hotter than normal this September with a mean temperature of 13.9C (1.2C above the long-term average).
That puts it joint fourth in the list of warmest Septembers since records began in 1910.
But the outlook for October does not look so settled.
"The first few days will see mainly dry, warm weather," said Peter Sloss. "But a front will bring a spell of wet and windy weather to Scotland and Northern Ireland on Friday, crossing England and Wales overnight.
"Temperatures will fall away and we will be back to more normal mid-autumn weather."
The record low rainfall this month follows an exceptionally wet year so far, including torrential rain at the end of August and the wettest winter on record.
Trevor Bishop, the Environment Agency's deputy director of water resources, said that means there's no danger of a dry September leading to water shortages.
"We look ahead by modelling how rivers and groundwater may respond to different future rainfall patterns," he said.
"The results show a broadly positive picture and even if rainfall is below average this autumn the country will not go into drought."