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A JUNE SNOWFALL IN NORTHERN YUGOSLAVIA

By C . G. HOLMES Hitchin, Herts.

NOW was the last subject on our minds when we finally chose a holiday at S Lake Bohinj which is near the Austrian-Italian border of Yugoslavia. We chose this mountain resort primarily to escape the June heat of the Adriatic coast, and consultation of Tables of temperature, relative humidity andprecipita- tion for the world, Part 111, supported our choice:

Mean daily temperature Absolute range (“Cj extremes (“C)

Max Min Max Min

Zagreb 24.4 14.4 32.8 3.2 (Yugoslavia) 162 m (period 1862-1935)

Klagenfurt 23.3 11.7 34.4 1.7 (Austria) 450 m (period 1921-1955)

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The station at Zagreb lies on a post-glacial flat plain while Klagenfurt is a valley station in the Karawanken range of mountains, Austria. Lake Bohinj (pro- nounced Bok-hinge) lies among the Julian Alps with surrounding peaks as high as 1000 to 2000 in. The lake's altitude is 525 m which is not particularly high when compared with Innsbruck at 578 m, Munich at 537 m and Salzburg at 435 m.

Saturday 8 June was the departure date and we left Luton airport after the first heavy rain since 10 March. After the rain a cool north-westerly airstream set i n (Fig. 1). On arrival, we put a Six's thermometer on the hotel balcony some 10 m above ground level and facing south-south-east to give an approximate air temperature reading. The first complete day in Yugoslavia, 9 June, was mainly overcast with cirrostratus giving light rain; temperatures at balcony level reached 20.5"C during the day (Fig 2). Surface winds were south-south-east Force 1 while high cloud drifted slowly from the north-west - a good indicator of unsettled weather. By late evening a prolonged thunderstorm had set in with typical conti- nental ferocity, ensuring little sleep until the early hours of the morning.

Monday morning at 0900 saw continuous heavy rain and, to my surprise. a temperature reading of 3"C, after a minimum reading of 1°C. Several people reported that snow had covered the ground for a short time around 0700. Stratus clouds clung to the mountain side, thinning occasionally to reveal a snow cover as low as 700 metres. At 1200 (Fig. 3) the temperature still showed 3°C and, while we were observing the slow movement of clouds, large flakes of snow began to fall. This sleet lasted for 15 min preceding a change to drier conditions by 1400.

The following day was fine and sunny and, with good visibility, there were splendid \. iews of the surrounding snow-capped mountains. Several hotel residents ascended by cable car from lake level to 1500 m or more and at this height snow had accumulated to depths of approximately 30 cm, with drifting in places. Local inhabitants remarked that this was bound to happen after a relatively snow-free winter and very warm spring. Our local coach driver com- mented that he had never known snow to fall and settle in June at such a low level.

F I ~ . 1. Synoptic chart for 1200 hr, 8 June 1974 based upon Dairy Weather Report

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Fig. 2. Synoptic chart for 1200 hr, 9 June 1974 based upon Daily Weather Report

Fig. 3. Synoptic chart for 1200 hr, 10 June 1974 based upon Daily Weather Report. Note the temperature of 7°C at Klagenfurt while Zagreb further south is warmer with 14°C

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