24-25 February 1995
Severe Tropical Cyclone Bobby moved slowly and erratically along the Pilbara coast crossing just to the east of Onslow between midnight and 1 am on the 25th. Seven lives were lost when two fishing trawlers were sunk off the coast from Onslow. Bobby was at its strongest prior to crossing the coast at 5 pm on the 24th, having estimated maximum wind speeds of 270 km/h near the centre. The highest recorded wind gust was 183 km/h at Onslow. Offshore a gust to 166 km/h was recorded on Varanus Island (one of the islands in the Montebello group).
Very heavy rainfall accompanied Bobby. More than 400 mm of rain fell in the Onslow area during the period of the event. Very heavy rain extended inland through the Gascoyne and Goldfields as Bobby became a rain bearing depression. Many centres registered record monthly rainfall totals.
Figure 1. Infrared satellite image of TC Bobby at maximum intensity, 5 pm 24 February 1995.GMS image courtesy of Japan Meteorological Agency.
Track and Intensity
TC Bobby developed from a tropical low that moved westwards across the Timor Sea during 20-21 February. It was named as a category 1 cyclone at 7 am on Wednesday 22nd February when located about 500 km north of Port Hedland. Bobby continued to intensify, reaching category 3 status by the morning of the 23rd when it was about 250 kilometres to the north of Karratha.
The cyclone commenced a more southerly track and slowed down during the 23rd and 24th as it moved closer to the west Pilbara coastline. The cyclone was very near the coast to the west of Mardie by late afternoon on the 24th and had further intensified to category 4 status. The path of the cyclone was very erratic during the evening of the 24th as it moved along the coastline towards Onslow. It eventually crossed the coast just to the east of Onslow between midnight and 1 am on the 25th, then moved slowly southward over land and began to weaken. By the morning of the 26th it was located just to the southeast of Gascoyne Junction and had been downgraded to category 2 intensity. Bobby weakened to a rain bearing depression as it moved across the Gascoyne and Goldfields during the 26th and 27th.
Seven lives were lost when two fishing trawlers were sunk off the coast from Onslow. A motorist was drowned inland from Carnarvon while attempting to cross a flooded creek. Very minor property damage was reported from the Karratha area. Many trees were blown down. About 20 houses at Onslow suffered superficial roofing damage. Pastoral stations along the track between Onslow and Gascoyne Junction reported property damage.
Very heavy rain associated with the cyclone caused serious flooding in the west Pilbara, Gascoyne, Goldfields and Eucla regions. Rainfall associated with this event followed heavy rains over a large part of inland WA earlier in the month. Several centres in the Goldfields received record rainfall totals for February.
Figure 4. Monthly rainfall totals for February 1995 showing totals exceeding 200 mm through parts of the Pilbara, Gascoyne and Goldfields as a result of TC Bobby.
Note: Heavy rain over the Kimberley region on the 17th and 18th of February was due to heavy monsoonal thunderstorm activity over the region but was not associated with Bobby.
Cyclone Parameters at the time of maximum intensity
Date/time: 5 pm 24 February 1995
Lowest estimated pressure: 925 hPa
Maximum estimated wind gust : 270 km/h