HOT and humid days will be back this week, the weather authority predicts.

It will be quite cool this morning as the cold front lingers in the city, with morning temperatures set to dip below 20 degrees Celsius in suburban areas and 22 degrees downtown. Highs will hover around 27 degrees.

The respite will be short-lived as a subtropical high will soon return and take control of the city skies.

After a short break from rain today, showers will hit the city tomorrow and the high will climb to 28 degrees. On Wednesday and Thursday, showers will turn to drizzle and the temperature will rise to 30 degrees. Rain will lessen on Friday and temperatures edge up.

Bailu, or white dew, in the Chinese calendar, begins on Saturday. Traditionally, from this day on, cold air expands southward and temperature starts to fall. There should be greater variations of temperature between day and night.

Over the 15-day bailu period, the city’s historical average temperature is 24.7 degrees and average precipitation 65.5 millimeters.

There is little chance of “high temperature” days (35 degrees or more) during the period.

Xujiahui weather station has only recorded such days in one out of every 10 years since 1873.