MG 1:59.1.27 :מטרא בעננא ממסא מסי‏ : the rain actually condenses in the cloud
See the entire entry for msy vb. to melt, rot

MG 1:59.1.27 :דרעים רעמא‏ : the thunder thunders (in the cloud)
See the entire entry for rˁm vb. to thunder

MG 1:59.1.27 :דרעים רעמא ובריק ברקא ואתי מטרא‏ : the thunder thunders, the lightning flashes, and the rain comes
See the entire entry for rˁe/am, raˁmā n.m. thunder