The duration of snow cover was again moderate; the average at 2500 ft. on the mountain groups used as indices in these reports was 79 days, which is the average for the past six seasons.
Diagrams showing the distribution of snow cover relative to height for seven stations are given on page 361.
Harris, in the Outer Hebrides, reported snow cover in each month from September to April. The snow line reached sea level on 8 days in the season, and the maximum duration of cover occurred in December with 13 days above 1500 ft.
The Cuillins of Skye had some cover in each month from September to March, with a maximum of 27 days in December down to 3000 ft. The snow line fell to sea level on to days during the season.
The peaks around Glen Lyon also had cover in the months September to April, with a maximum duration of 25 days at 3000 ft. in December and at 3500 ft. in April.
The summit of Ben Nevis was under continuous cover from October 1st to July 4th, a total of 277 days, and down to 2000 ft. the mountain was under snow continuously throughout December and January. The snow line reached sea level on only 5 days, all in February.
The Paps of Jura were snow-free in September, October, January and May. The maximum cover occurred in December with 12 days’ cover down to 1500 ft. The snow line fell to sea level on one occasion only, April 3rd.
The Caernarvonshire peaks were under cover some time in each month of the season, but only on the extreme summits for one day in October and May. The maximum cover was in December with 25 days at 3000 ft.
No snow cover was observed on the Brecon Beacons in September, October or March, and only the extreme summits were covered in April. The summits were under continuous cover throughout December and February.
Curves showing total seasonal duration at five stations up to 3500 ft. are drawn in Fig1 (p. 362): 200 days’ cover was exceeded on Ben Nevis at and above 3000 ft., and 100 days’ cover was reached on the mountains about Glen Lyon and on the Brecon Beacons above 2500 ft.
