The shift from the Imperial to the Metric System in Canada started 40 years ago on April 1, 1975. No joke. All weather forecasts switched to Celsius. Dave Phillips, senior climatologist with Environment Canada was there. He explains why he was glad Twitter didn't exist when the change was made.

He spoke with CBC Hamilton's Conrad Collaco about what it was like in 1975 when the country changed from Fahrenheit to Celsius. It wasn't a happy time in the weather office at Environment Canada. Phillips also offers his take on the weather we're likely to experience this April.

Listen to the interview on this page.

As for today's weather in Hamilton, get ready for a high of 8 C with a mix of sun and cloud clearing this morning. After a long and cold winter that might feel like swimming pool weather. More clouds will come this evening but the low will be 3 C.

The temperature is expected to hit double digits to close out the week, with a pair of warm rainy days in the forecast for Thursday and Friday at 14 and 10 C, respectively.