More than 170,000 people in the two countries were evacuated to safety before the arrival of Cyclone Biparjoy.
Forecasters say it could be the area's worst storm in 25 years and warned it threatens homes and crops in its path.
The cyclone is due to barrel through parts of India's Gujarat state and Sindh province in Pakistan.
Cyclone Biparjoy - meaning "disaster" in Bengali - is forecast to hit the coast near Jakhau port, between Mandvi in Gujarat and Keti Bandar in Sindh.
Pakistan's disaster management agency warned of storm surges as high as 3-4m (10-13ft) along the coastline from Karachi to Gujarat.
Alok Pandey, the official in charge of relief operations in Gujarat, said earlier that the cyclone's intensity had reduced but that wind speeds were still expected to be at "very dangerous" levels of around 110-125 km/h (68-78mph) at the time of landfall.
The Indian armed forces and coast guard have kept ships, helicopters and aircraft on standby for rescue and relief operations.
Gujarat's health minister, Rushikesh Patel, asked people to avoid travelling. "Our aim is to ensure zero casualties," he said.
At least seven deaths were reported amid heavy rains in India earlier this week. The victims included two children crushed by a collapsing wall, and a woman hit by a falling tree while on a motorbike, AFP news agency reported.