BMKG Urges Caution as High Waves up to 4 Metres Hit Southern Central Java Waters

The Meteorology, Climatology and Geophysics Agency (BMKG) has forecast potential high waves of 2.5 to 4 metres in the southern waters of Central Java, covering the areas of Cilacap, Kebumen and Purworejo. These conditions, which pose a risk to shipping safety, are expected to persist until Friday (21/8).

Adnan Dendy, a forecaster at the BMKG Tunggul Wulung Cilacap Station, reminded maritime operators to increase their vigilance. “Be alert to high waves in these southern waters, which are quite risky for shipping activities such as fishing boats and barges when wind speeds exceed 15 knots,” said Adnan Dendy.

Meanwhile, different conditions prevail in the northern waters of Central Java. Retna Swasti Karini, a forecaster at the BMKG Tanjung Emas Semarang Maritime Station, said wave heights range from 1.25 to 2.5 metres at several points, including the western and eastern parts of Karimunjawa, Jepara and Pati-Rembang. Other northern waters range from 0.5 to 1.25 metres.

Retna added that the tidal flooding phenomenon in the northern waters has subsided, with a maximum height of 0.8 metres recorded between 05.00 and 06.00 WIB. However, floodwaters in coastal areas along the northern coast, such as Pekalongan and Demak, have yet to show signs of receding.

Wind patterns in the eastern part of Central Java are blowing from the northeast to the southeast at speeds of 2 to 20 knots. These conditions are considered risky for fishing boats when wind speeds exceed 15 knots, and for barges when winds exceed 16 knots.

On the other hand, BMKG has also noted the potential for rain in several inland areas. Agus Triyono, a forecaster at the BMKG Ahmad Yani Semarang Meteorological Station, said that although the dry season is still ongoing, light rain is likely to fall in six areas, particularly in mountainous and highland regions.

Weather from morning to midday is generally clear to cloudy. However, from late afternoon to early evening, light rain is forecast in Purbalingga, Banjarnegara, Wonosobo, Kajen, Slawi and Bumiayu. This phenomenon has also made air temperatures in these areas slightly warmer. Meanwhile, other areas in Central Java are predicted to be clear to cloudy throughout the day.

In general, winds are blowing from the east to the south at speeds of 10 to 35 kilometres per hour. Air temperatures range from 16 to 34 degrees Celsius with humidity of 45 to 95 percent.

“Be alert to strong winds as well as forest and land fires,” urged Agus Triyono.