started off (in the country) with localised then generalised flooding (on a major scale) very rapidly. by the time we were ready to get moving to another location, we received news that that place had been inundated...rapidly leaving nowhere to go...all the water was polluted & contaminated, not safe to go into, let alone drink...managed to save some personal items...there were roaming groups of wild animals (lions???) hunting & eating dead, injured & intact survivors...had to suffocate one of them with a pillow whilst being bitten & clawed...
moved off to a city (don't know where...) then received news of a 'comet that strikes the mountain' (don't know if this refers to anything, but...)
sure enough the comet hits - volcanoes, earthquakes, tsunamis & firestorms ensue...the city remains a 'safe' haven...
until...something 'strange' goes on with the sun...at specific times - morning, evening & changes in the weather...the sun starts emitting particles/beams that go through solid objects (like concrete & metal) & vaporise humans, burn trees & vegetation and leave absolutely nowhere to hide except deep underground, there was no shade, everything became spectral light (like rainbows in the beams/particles)...
the humans that manage to 'survive' these solar beams become mutant zombie like creatures making something else to defend against & be ware of...these creatures inhabit the underground...i woke up several times during this dream, but always ended up back in it...it seemed to last all night...