Chongming weather in May

In May, Chongming has daytime highs averaging 22 °C, nights around 17 °C, with 9.4 wet days, and a sea temperature of 18 °C. Figures are 1991–2020 climate normals.

  1. Jan
  2. Feb
  3. Mar
  4. Apr 14°
  5. May 20°
  6. Jun 23°
  7. Jul 27°
  8. Aug 27°
  9. Sep 24°
  10. Oct 19°
  11. Nov 14°
  12. Dec

Daily temperatures through May

13°20°27°18152229
Daily highDaily low Day of month on the horizontal axis. Highs peak at 24.4 °C and lows bottom out at 15.1 °C.

How May develops

Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.

DaysAvg highAvg lowChance of rain
1–10 May21.0 °C15.8 °C32 %
11–20 May22.3 °C17.4 °C31 %
21–31 May23.6 °C18.8 °C28 %
0%50%100%151015202530
Chance of a wet day (over 1 mm) by date in May. Wettest date over the 30 years: May 31, at 47 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical May Share of the month
Days above 25 °C 5.3 of 31 17 %
Days above 30 °C 0.3 of 31 1 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 9.4 of 31 30 %

Conditions in May

MeasureAverage
Mean temperature 20 °C
Record high (1991–2020) 33 °C
Record low (1991–2020) 8.1 °C
Relative humidity 80 %
Wind speed 20 km/h
Cloud cover 67 %

May compared with the months around it

Month Avg high Rainfall Cloud
March 12.2 °C 91 mm 66 %
April 17.4 °C 99 mm 66 %
May 22.4 °C 120 mm 67 %
June 25.6 °C 258 mm 78 %
July 29.6 °C 170 mm 69 %

See all twelve months for Chongming

Nearby destinations in May

Destination Avg high Wet days Sea
Chongming 22 °C 9.4 18
Baoshan 24 °C 9 19
Shanghai 24 °C 10 19
Qibao 24 °C 10
Kunshan 25 °C 10
Qingpu 25 °C 10
Songjiang 25 °C 10
Nanqiao 24 °C 10 19
Fengxiang 23 °C 10 19

QuestionsMay in Chongming, answered

How warm is Chongming in May?

Daily highs average 22 °C and nights fall to about 17 °C, a spread of 5.0 °C between afternoon and dawn. That makes May the 5th warmest month of the year here.

Does it rain much in Chongming in May?

May averages 120 mm of rain, spread over about 9 of the 31 days — 30 % of the month. Cloud cover averages 67 % of the sky.

Is the sea warm enough to swim in May?

The sea averages 18 °C off Chongming in May. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.

How long are the days in May?

Chongming averages 14 hours between sunrise and sunset in May. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.