Tropical Cyclone Narelle, or at least its remnants, are contributing to hot, humid and thundery weather across a large area of Western Australia. Narelle has helped draw tropical moisture and a low pressure trough across much of the west of the state, leading to storms, hugh humidity and heat. It has led to a very warm night in the southwest, including Perth. Overnight temperatures were five-to-10 degrees above average across the South West Land Division. At 3am this morning Perth was 31 degrees, equal to the average daytime maximum temperature for January. Perth had an overnight low of 27.3, nine degrees above average and the second time this summer it has had a night this warm. The last time Perth had more nights this warm in a summer was in January 1989 when there were three nights warmer than 27.5 degrees. Perth airport had its warmest night in two years and warmest January night in at least 69 years with a minimum of 27.8 degrees, 11 above average. Regarding rain and storms, sharp heavy falls have affected parts of the southwest. This comes after the Central West, Central Wheat Belt and Goldfields were hit by up to five times its monthly rainfall in the last few days, widespread 20-to-50mm. Early this morning Manjimup, south of Perth, received 19mm of rain in just 30 minutes as a brief thunderstorm rolled through. The main storm area has moved further southeast, to between about Albany and Esperance with potential for further heavy falls and also damaging winds. The area between Perth and Albany is not in the clear yet. The southeasterly movement of Ex-Tropical Cyclone Narelle from west of the city to south of Albany in the next 24 hours will increase instability. Thunderstorms with potential for heavy rain and damaging winds are possible between now and Wednesday morning. Cooler southwesterly winds will then bring a few showers and maximum temperatures in the mid 20s, about 10 degrees cooler than the last few days.