Parts of western NSW have just had their best rain in four to five years and there's plenty more wet weather on the way.

An upper-level trough interacting with abundant moisture in the atmosphere has caused heavy and steady rain to soak parts of NSW during the last 24 hours.

Some of the best falls on Wednesday into Thursday morning were over the state's central and northern inland.

Walgett and Dubbo both collected 65mm of rain during the 24 hours to 9am on Thursday, which were their highest daily totals in five and four years respectively. Coonamble's 86mm was its best drop in two years.

Further east, rain has also been increasing along the northern and central coasts of NSW on Thursday morning in response to a deepening coastal trough.

A rain gauge at Bungwahl, near Forster, collected 142mm during the 24 hours to 9am Thursday. This is about a month's worth of rain for the site at this time of year.

As of midday on Thursday, several warnings and alerts were in place for eastern NSW. These included:

• A severe weather warning for heavy rain and damaging winds along the coast and adjacent inland from the Central Coast up to the area just south of Yamba
• A flood watch for the Mid North Coast, Hunter and parts of Sydney
• A hazardous surf warning for the Coffs Coast, Macquarie Coast and Hunter Coast on Friday

Rain will continue to fall over both eastern and western NSW during the rest of Thursday. However from Friday, the bulk of the rain will be over the state's eastern districts where it will be heavy and continue into the weekend.

Image: Forecast rain on Thursday, March 18th, according to the ECMWF model.

Some parts of the coast and adjacent ranges could see over 200mm of rain between now and Sunday, with both flash and riverine flooding a risk.

Check the latest warnings and flood watches for the most up-to-date information on this evolving weather event.

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