Tropical cyclone Narelle may have not reached its full fury, but it played a big part in the hot and muggy conditions that had Perth residents ducking for cover yesterday.
High humidity during the day had tired people venting their discomfort after an extremely hot night that made for an uncomfortable night's sleep.
Some said it felt like they had woken up in the State's north after the sticky Monday night, which was the hottest January night on record in 24 years.
The mercury did not drop below 30C until 7pm and the minimum dipped to 27.3C - just 0.5C below the 27.8C posted on 21 January, 1989.
With humidity consistently hovering about the 50 per cent mark, the apparent temperature, which takes into account factors such as humidity and wind speed, has been above the actual temperature for the past two days.
Relative humidity levels hit 67 per cent at 2pm yesterday.
Weather Bureau meteorologist Patrick Ward said it had been particularly humid in Perth because ex-tropical cyclone Narelle was coming down the coast and sending tropical moisture to the southern parts of WA.
Mr Ward said Perth had not seen the gusty winds from the east that typically cooled the city over summer.
The bureau forecast that UV levels in Perth would hit 14 today.
In the South West, a suspected tornado formed near Capel just after 6am, with big trees pushed over in a trail of destruction about 400m wide near the Ludlow State Forest.
Debris littered Tuart Drive and the Bussell Highway, but no damage to buildings or property was reported.The same storm produced 19mm of rain in half an hour at Manjimup.