Yes, there are multiple flights from Stanfield International to Changi Intl for under S$ 1,591. The cheapest flight booked recently is on Multiple Airlines for just S$ 1,474, but on average you can expect to pay S$ 1,489.
There are no direct flights from Stanfield International to Changi Intl, but Cheapflights can provide you with all the information you need to find the fastest route with the fewest stops.
Expected rainfall in Halifax is less than in Singapore City Airport. You can expect this to be the case over the next 17 days.
Expect the weather to be around 33 °C on average in April. As the temperature peaks, try to get your plans done early, as flight price and availability will have an impact on your travels. The climate in Singapore City Airport is generally hotter than in Halifax.