The PSLV-C20 is slated for blast-off at 5.56 pm local time from the Satish Dhawan Space Centre, at India's space port Sriharikota in Andhra Pradesh. President Pranab Mukherjee is expected to witness the event. Mr Mukherjee will be the second President after Dr APJ Abdul Kalam to witness a PSLV launch; Dr Kalam was present in Sriharikota during the PSLV launch on May 5, 2005.
The 44-metre tall rocket, headed towards its 23rd consecutive launch, will sequentially drop off the satellites in space in less than half an hour after the launch. Later this year, a similar rocket will ferry India's maiden mission to Mars, Mangalyaan.
PSLV has an impeccable record of 21 consecutive successful flights. This is the ninth time ISRO is using the 'core alone' variant of the rocket.
ISRO had initially planned to launch SARAL on December 12 last year but postponed it to carry out additional tests to "address technical issues to ensure reliability".
The ISRO-built SARAL is a 410-kg satellite with payloads - Argos and Altika - from French space agency CNES for study of ocean parametres towards enhancing the understanding of the ocean state conditions which are otherwise not covered by the in-situ measurements.
In view of the expected presence of the President, the Satish Dhawan Space Centre has been put under a thick net of security, officials said.
SARAL will provide data products to operational and research user communities, in support of marine meteorology and sea state forecasting; operational oceanography; seasonal forecasting; climate monitoring; ocean, earth system and climate research, the officials said.
Altimetre (Altika) would help study the sea surface heights while Argos payload is a satellite-based data collection platform.