Unusually warm water in the Coral Sea is fuelling showers and thunderstorms over Queensland this week.

Sea surface temperatures in the western Coral Sea are currently 2-3 degrees above average for this time of year. This abnormal warmth is causing more water to evaporate into the atmosphere.

Image: Sea surface temperature anomalies on February 23rd, 2020. Source: NOAA Coral Reef Watch

Over the last few days, a high pressure system passing over the Tasman Sea has been directing this moisture-laden Coral Sea air towards Queensland, resulting in heavy rain and storms in some areas.

Parts of the state's tropical east coast have received 200-300mm of rain since last Friday. This included two-day totals of 318mm at Mount Charlton, to the northwest of Mackay, and 235mm at Port Douglas. Mackay Airport's 185mm during the 24 hours to 9am on Monday was its highest daily total in three years.

Further inland, parts of Queensland's Marrenoa and Warrego District collected the best rain in several years on the weekend. Charleville Airport's 86mm during the 24 hours to 9am on Saturday was its heaviest rain in a decade, while St George's 62mm during the same period was an eight year high.

At midday on Tuesday, major flooding was occurring in a number of rivers across the Maranoa and Warrego District. These flood peaks will continue to gradually make their way downstream into northern and western NSW during the coming days and weeks.

Looking ahead, widespread showers and thunderstorms will continue to affect Queensland through the middle of this week, before easing and contracting towards the state's north and east from Friday. 

Some models indicate the potential for a trough or low pressure system to enhance rain over southeast Queensland this weekend or early next week. At this stage, it's too early to know whether or not this will happen, so keep an eye on the latest forecasts and warnings later in the week.

The unusually warm water in the Coral Sea is also threatening to cause widespread coral bleaching across the Great Barrier Reef within the coming weeks. 

Based on current heat stress, temperature trends, and our Four-Month Bleaching Outlook model, Coral Reef Watch is expecting widespread bleaching conditions across the GBR in the coming weeks. So far, it looks like it may not be as intense as 2016 or 2017. Fingers crossed! pic.twitter.com/8YDMlL7bnB

— Coral Reef Watch (@CoralReefWatch) February 20, 2020

Coral bleaching has already started to occur in some parts of the reef and could become more widespread if the western Coral Sea stays warmer than usual into the opening weeks of March.