Bad weather may not mean that an autoland is needed. To pass through that "assigned altitude" in bad weather, though, some things must be in view. Either the runway, runway end lights, the "rabbit" (sequenced strobes),runway threshold, runway threshold lights, any of these or all of them. To pass below the DH (decision height), there are criteria to be met. If on an ILS, the usual DH is 200 ft AGL, but it may be higher for some circumstances. For ILS autolands, it depends on carrier-specific details. The runway MUST have CAT III and/or CAT II ILS capabilities or the autopilot has NOTHING to land with, trust me! :-)For visual or radar approaches, the DH is much higher, so autolands cannot be done without visual cues when using radar.