The 1849 LDS edition accidentally replaced the singular tempest with the plural, but the singular was restored in the 1920 edition, probably by reference to one of the earlier editions. The prepositional phrase “by tempest” is associated with two following by-phrases, both of which have singular nouns (fire, smoke, and vapor). But the preceding with-phrase has plurals (thunderings and lightnings), which undoubtedly led to the 1849 typo.
We find that in conjuncts the word tempest agrees in number (singular or plural) with the nearest nouns, as in the following examples involving prepositions:
The two examples in 3 Nephi 8 actually involve early textual variation between tempest and tempests, but in each case the evidence supports the plural. (See the discussion for those two verses.) Here in 1 Nephi 19:11 there is no difficulty in determining the original text since the plural was accidentally introduced considerably later in the printed editions.
Summary: Based on the earliest textual sources, maintain the singular tempest in 1 Nephi 19:11; the following singulars in “by fire and by smoke and vapor of darkness” support the singular tempest.