Here are the latest developments in this story:
River Jhelum has breached embankments, hitting Srinagar badly. Chunks of city are under water, without electricity and phone services. People have fled to safer areas. Others have moved to terraces and are making desperate calls for help. The ground floor of a government children's hospital in the heart of the city is flooded and is facing a blackout.
Flood has affected almost all 10 districts in the Jammu region. Landslides triggered by heavy rainfall have damaged roads, dozens of bridges, buildings and crops. Vehicular traffic has been stopped on the Jammu-Pathankot highway. The state government has closed all schools till September 7.
"There is some improvement in Jammu, but the situation is worsening in Kashmir, especially Srinagar. I want to appeal to people not to panic. We've been assured that 40-50 boats will be sent to Srinagar. Choppers are ready, planes are also on stand-by," said Chief Minister Omar Abdullah..
Air Force choppers have been authorised to rescue stranded people in Srinagar. One chopper, which went for a rescue mission from Jammu at 6 AM, is yet to return. Boats flown in from Delhi have been launched in Srinagar's worst-affected areas - Indranagar, Shivpura and Rajbagh.
Army has pressed into service 23 aircraft, the Air Force has pushed in 26 choppers. Three C-130J Super Hercules special operations aircraft are transporting boats and relief material from Pune and Gandhinagar to Srinagar. Medical teams and equipment have been sent from Delhi.
Katra-bound trains have been halted. Haj flights scheduled up to September 12 have been postponed.
"This is not a problem of the state alone, it is a national calamity. At the moment, relief operation is a priority. Rs 1,100 cr is already with the state government, I provide Rs 1,000 cr as additional assistance," said Prime Minister Narendra Modi, who is on a visit to the state.
Several thousand villages across the state have been hit and 350 villages are submerged, the home ministry said on Saturday.
The southwest monsoon is vigorous over Jammu and Kashmir. Heavy rains will continue till tomorrow, the weather department has said.
For information and assistance, please call these helpline numbers: Delhi J&K House - 011 24611210 and 24611108; Srinagar - 0194-2452138; Jammu - 0191-2560401