This topic was of great interest back 65 years ago when RADAR operated in the VHF range. The MIT RADLAB series volume 13 covers this. It has also been reprinted in recent years.
Propagation of Short Radio Waves by Donald E. Kerr
As a summary, you will get very strong reflection from the ocean surface and there will be temperature and humidity inversion layers in the region above the surface that will produce a waveguide effect which has low attenuation for long distances.
There is a famous case around 1942 where a RADAR on the south-east coast of England was able to image the sea shore of Norway. This was for a RADAR designed to find airplanes out to 10-50 miles maximum range.
Another famous case was a ham in Hawaii contacting one in California on the 2 m band back around 1960. This was well planned with high antenna gain and RF power on each end.