A major flood peak, which is slowly moving down the Lachlan River in Central West NSW, will reach Forbes during the next 24-48 hours.

Last week, a low pressure system interacting with an abundance of moisture-laden air triggered several days of rain and thunderstorms over NSW.

The map below shows how much rain fell across the state last week, with most of this hitting the ground in the space of 1 to 3 days.

Image: Observed rain during the 7 days ending at 9am on November 14th. Source: Bureau of Meteorology

Last week's heavy rain, which fell into already saturated catchments in some areas, caused rivers to bulge and some dams to overflow. As of Monday morning, Lake Wyangala was sitting at 103.4 percent of capacity, which is slightly lower than it was on the weekend.

Video: Water being released from Wyangala Dam in Central West NSW on Saturday, November 13, 2021. Source: @annaglynn_artist / Instagram

While drier weather has now returned to most of NSW, flooding continues in some areas.

A major flood warning remains in place today for the Lachlan River, while moderate flood warnings are also in place for the Belubula and Macintyre rivers.

According to the flood warning that was issued at 12:34pm AEDT on Monday, major flooding is occurring on the Lachlan River at Nanami, where river levels are higher today than they were during the September 2016 flood.

Image: River level observations for the Lachlan River at Nanami during the last four days, showing a major flood level continuing to rise into Monday afternoon. Source: Bureau of Meteorology

As this water moves further downstream, major flooding is likely to occur at Forbes from Tuesday and peak on Wednesday, possibly around the 10.65 metre mark. This level of flooding at Forbes would be similar to September 2016.

A number of roads are closed in Central West NSW today as a result of the flooding, including parts of Lachlan Valley Way south of Cowra and The Escot Way.

Burrendong Dam is also brimming after last week's rain, sitting at 126.4 percent of its capacity on Monday. Some minor flooding is occurring downstream of the dam today.

You can check the latest river levels here and flood warnings here.