A Severe Thunderstorm lashed Metropolitan Manila and nearby areas late yesterday afternoon, June 21, causing flash floods to occur once again along the busy thoroughfares and flood-prone areas of the metropolis. Although we are in the middle of the first “Monsoon Break”, there is no guarantee that rains especially thunderstorms will not occur in the country.
The said localized thunderstorm which occurred between 5:00 pm until 7:00 pm – was caused by a passing Surface Trough – an elongated area of slightly lower air pressure that resulted in the formation of these rain clouds.
The thunderstorm started at around 4 to 5pm as shown on the satellite imagery where very cold cloud tops appeared (see Figure 1).
Rainfall observations on all WeatherPhilippines and Manila Observatory rain gauges in and around Metro Manila, have recorded unprecedented downpour during the duration of the severe thunderstorm which occurred between 5:00 pm until 7:00 pm.
The first hourly data from 5:00 pm to 6:00 pm showed its significant highest rainfall of 85.4 mm recorded in F. Blumentritt, San Juan City (MO), followed by 65.0 mm in Quezon City Hall (LCP), then lastly at 59.0 mm in Diliman, Quezon City (DOST ASTI) (see Figs. 2 and 3).
As for the second and last hourly data, between 6:00 pm to 7:00 pm, the rainfall started to recede on the areas previously affected, and has moved southwestward into the southern areas of Metro Manila. Areas like in SM Bacoor as well as in Imus City have recorded an hour rain of 48.6 mm and 40.8 mm, respectively (see Fig. 4).
Always remember to check our WeatherPhilippines app and or our website at https://www.weatherph.org for the latest rain forecast especially during the afternoon or evening. It is better to be #WeatherWiser, rather than #WeatherFools. 🙂