It will also be windy, with gales expected about the coast.
The high is expected to be about 16C on Wednesday, likely to occur before the southerly rolls in, with a overnight low of 6C.
"Thursday is very much affected by those southerly winds."
He said there would likely to be showers throughout the day, with a brief respite in the late morning, before second southerly change.
Thursday would see a high of 15C with an overnight low of about 6C in the Napier/Hastings area.
The southerly will linger until Friday, with showers, south-westerly winds, possibly reaching gale force, with an expected high of 14C, and an overnight low of 5C.
Hawke's Bay is not the only area to have a wet and wild mid week. Lee said much of the North Island and the top of the South Island will also be hit by the bad weather.
"The initial feature which is bringing the severe weather with it looks like to be affecting just the North Island."