The Bureau of Meteorology has cancelled a severe storm warning for the ACT for heavy rainfall and flash flooding.
The bureau initially said heavy rainfall, which could cause flash flooding would likely hit the ACT and surrounding region on Thursday afternoon.
"A humid air mass lies over eastern and central New South Wales, and a surface trough lies through the interior," the bureau said in a statement.
"An upper level trough is entering the state from the west, and the combination of ingredients is promoting storm activity."
The warning was cancelled about 7pm.
A warning for large hailstones, damaging winds and heavy rainfall has also been issued for large parts of western NSW.
