The Met Office is forecasting temperatures to rise as high as 21C over the next few days.
It has also it could get up to 10C warmer than the average for April across the country, reaching 25C in some parts.
Here is your latest day-by-day forecast for Portsmouth:
It’s going to be a cloudy day although temperatures could reach as high as 15C later on in the day - between 5pm and 6pm. Pollen levels are high and the Met Office has put out a warning to hay fever sufferers.
A sunny day with some cloudy intervals around lunchtime. Highs of 17C during late afternoon and it will continue to be warm into the evening. Although temperatures will be high it will still feel slightly cooler because of the wind.
Temperatures of up to 19C have been forecast, and with the drop in wind speed it should be the warmest day of the week so far. It will be very humid though, especially at the start of the day and in the evening.
The Met Office is forecasting Friday to be the warmest day of the week with temperatures of up to 21C. The hottest part of the day will be the early afternoon where most parts of the south will have temperatures of more than 20C.
Saturday and Sunday
Fear not - the sun will still be out for the weekend although the mercury will show closer to 15C. With little wind and cloud on the forecast, it’s time to enjoy the (unofficial) start of summer!