Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
plŭvĭālis, e, adj. [pluvia], of or belonging to rain, rainy, rain-: Auster, rainbringing, Verg. G. 3, 429: Haedi, id. A. 9, 668: sidus, Ov. M. 3, 594: fungi, which are produced by rain, id. ib. 7, 393: aqua, rainwater, Sen. Q. N. 3, 7, 4: dies, Col. 2, 13: imbres, Tac. H. 5, 23.