A severe thunderstorm has been forecast for central Victoria.

The Bureau of Meteorology said heavy rainfall should pass through the region on Wednesday afternoon.

Flash flooding is possible.

Update, Wednesday 7am

CENTRAL Victorians are waking up to a thick blanket of bushfire smoke.

Visibility at Bendigo Airport dropped down to five kilometres on Wednesday morning. On a clear day, visibility is normally 40 to 50 kilometres.

Bureau of Meteorology senior forecaster Rod Dickson said the hazy conditions around Bendigo were similar to what people in Melbourne were experiencing.

"The smoke haze is having an impact on visibility," he said.

VicEmergency warned central and north central Victoria would experience hazardous air quality on Wednesday.

People are encouraged to minimise their time spent outside in smoky conditions.

Anyone experiencing wheezing, chest tightness, and difficulty breathing should call Triple Zero.

Mr Dickson said a wind change should hit central Victoria late on Wednesday afternoon. The trough should push the smoke back towards the east of the state.

The smoke haze should ease in the coming days, Mr Dickson said.

Earlier

CENTRAL Victorians have been warned again about possibly dangerous smoke, as air quality dropped throughout the state.

Air quality in Bendigo fell as bushfire smoke drifted across the state, with health warnings issued for people and animals

VicEmergency has warned of moderate to hazardous air quality across the state.

Visibility at Bendigo Airport was eight kilometres on Tuesday morning. On a clear day visibility is normally 40-50 kilometres.

Mount Alexander Shire Council closed its swimming pools on Tuesday due to the poor air quality.

Read more: City's air quality unknown despite smoke haze

Visibility dropped as low as 2.5 kilometres in Bendigo on Monday January 6. Anything below 1.5 kilometres is considered hazardous.

Air quality in the city is unknown, as the Environment Protection Authority does not monitor it.

Bureau of Meteorology duty forecaster Miriam Bradbury said Bendigo's visibility started worsening on Sunday, but took a distinct dip on Monday night.

Ms Bradbury said Wednesday morning was likely to be pretty hazy still, but wind was likely to clear the smoke during the late afternoon.

She said conditions probably wouldn't clear completely until overnight on Wednesday into Thursday.

VicEmergency has warned smoke can affect people's health.

Read more: Mask demand in Bendigo high after fires

Anyone experiencing wheezing, chest tightness and difficulty breathing should call Triple Zero (000).

If you have concerns about your health, seek medical advice or contact Nurse on Call on 1300 606 024.

Symptoms of smoke inhalation can include itchy eyes, sore throat, runny nose, shortness of breath, coughing, vomiting, nausea and confusion.

Agriculture Victoria has warned some animals might show minor respiratory problems or eye irritation due to the smoke.

Cats, dogs and horses are all vulnerable to this.

Livestock owners have been warned that in areas with ongoing serious smoke they might want to consider relocating their animals.

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