Intense rainfall of over 200 millimeters are expected in Metro Manila and in nearby provinces on Wednesday as this year's fourth tropical cyclone named ''Dante'' will enhance the southwest monsoon after it developed into a tropical depression on Tuesday.

The state weather bureau announced that the low pressure area (LPA) at the east of Aurora province had developed into tropical depression ''Dante'' at 2pm.

The other LPA at the eastern side of Batanes "remains inside PAR (Philippine Area of Responsibility) and still has a medium chance of turning into a tropical cyclone within the next few hours." Another LPA outside the PAR is being monitored by the state weather bureau, forecasters said.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration raised the orane rainfall warning Tuesday night over Metro Manila, Rizal, Zambales, Bataan, Cavite, Laguna, Pampanga, Bulacan(Angat, Balagtas, Baliuag, Bocaue, Bulakan, Bustos, Calumpit, Malolos, Meycauayan, Guiguinto, Hagonoy, Marilao, Obando, Pandi, Paombong, Plaridel, Pulilan, San Rafael, Santa Maria, San Jose del Monte) and Batangas(Nasugbu, Talisay, Tanauan, Santo Tomas, Malvar, San Nicolas, Laurel, Agoncillo, Tuy, Balayan, Calaca, Lian, Lemery, Calatagan).

Metro Manila and its neighboring provinces experienced widespread flooding on Monday night following intense rainfall, which eased on Tuesday morning. The Metropolitan Manila Development Authority said there were 500 incidents of flooding but went down to 273 as of Tuesday morning. These ranged from gutter deep to areas where floods were deep, said MMDA chairman Romando Artes.

Metro Manila and other provinces were placed under red heavy rainfall warning, which meant more than 200 millimeters of rain, Monday evening. It was lowered to yellow, where rains of between 50 milimeters to 100 millimeters on Tuesday morning. It was raised to orange, which means rains of 100 millimeters to 200 millimeters, in the afternoon.

On Tuesday, Quezon City declared a state of calamity due to the floods, a congressman said in his Facebook post. Manila Mayor Isko Moreno said the city council will convene tomorrow to declare a state of calamity.

In a radio interview, state weather forecaster Glaiza Esculiar explained that "more than 200 mm of rainfall is expected to be experienced on Wednesday" as the southwest monsoon will be further enhanced by ''Dante''.

"We are expecting that the southwest monsoon will further enhance on Wednesday until Thursday in Metro Manila and in parts of Calabarzon and Central Luzon area," she said.

Esculiar said Dante has a low possibility to make any landfall but it is expected to cross the so-called Manila-Okinawa line in southern Japan.

"When the center of the storm or weather disturbance crosses this (Manila-Okinawa line) the Southwest Monsoon in Metro Manila and nearby provinces will become stronger," she added.

As of 5pm, Dante was last spotted at 1,115 km east northeast of Central Luzon or 1,130km east of Northern Luzon with maximum sustained winds of 45 kph near the gustiness of up to 55 kph while moving westward.

Dante may reach tropical storm category by Wednesday before it may exit the Philippine Area of Responsibility (PAR) on Thursday (24 July) or on Friday (25 July).

"Further intensification into a severe tropical storm remains less likely but is not ruled out," the state weather bureau stated.

Esculiar said the heavy rainfall is expected to shift to Ilocos Region from late Thursday to Friday when the weather disturbance moves north northwestward. Robina Asido/DMS