June heat drives 3.1% fall in GB milk deliveries

June’s extreme heat accelerated the decline in GB milk deliveries, with volumes falling 3.1% year on year as heat stress reduced cow yields.

AHDB estimates that daily deliveries averaged 35.51 million litres during the month, taking the total for June to 1.065 billion litres.

This was 34 million litres lower than in June 2025 and left supplies for the first three months of the 2026/27 milk year, from April to June, 1.7% behind last year.

Deliveries began the month only slightly below the elevated levels recorded a year earlier. However, they dropped sharply after exceptionally hot weather arrived during the second half of June.

By the week ending 4 July, volumes were 4.8% below year-earlier levels and had fallen beneath the five-year average.

AHDB linked the sharper decline to heat stress among dairy cows, which had a significant effect on yields during the hottest part of the month.

It said the reduction may also have been intensified by milk-volume management measures taken before the end of June.

While high temperatures deepened the monthly fall, several longer-term pressures are also weighing on GB milk production.

AHDB highlighted the declining milking herd, a reduction in dairy producer numbers and the use of volume-control schemes as important factors.

Lower milk prices and rising input costs are also squeezing margins across the sector.

A worsening milk-to-feed price ratio, meaning milk values have weakened relative to feed costs, is adding further pressure to production decisions.

AHDB now expects GB milk output across the full 2026/27 season to finish 0.9% below the previous year.

Early summer growing conditions had initially helped farms begin rebuilding forage supplies after stocks had fallen to low levels.

However, the more recent hot and dry spell is expected to slow grass and forage growth rates.

The availability of forage and straw could therefore become increasingly important if dry conditions continue through the summer.

With input costs remaining high and margins under pressure, AHDB said it would continue monitoring milk deliveries, weather conditions and feed availability as the season progresses.