Landspouts can occur in cumuliform clouds without the parent cloud rotating. Typically, these occur along weather boundary where air converges under weak vertical rotation. The convergence of air at the boundary forces it up forming a cloud and this updraft stretch the rotation increasing its spin.
Tornadoes can from these typically summer-time thunderstorms. Their appearance is usually long and slender and snake like. They are most common in Wyoming eastern Colorado and New Mexico where the cloud bases are rather high.
There is no RFD associated with landspouts. However, just because they are not from supercells, landspouts can be strong enough to produce EF-2 and EF-3 damage.
Waterspouts is a tornado over water. Some waterspouts form from supercells and if they move onshore are just as capable of producing as much damage as any land originated storm.
Other form waterspout quickly beneath a rapidly building line of cumulus clouds. While usually less violent, slower moving, and less destructive. Wind can still exceed gale force (34 knots/39 mph/63 km/h). This is strong enough to swamp or capsize a small watercraft.
