Quoting Commentary for I Kings 18:44

The thickness of the cloud which is called ערפל . Rashi is answering the question: Why are two terms [ עב and ענן ] necessary? עב also means cloud, as in (Yeshayah 19:1): “Behold, Hashem rides on a swift cloud ( עב ),” and as in (Melachim I 18:44): “Behold, there was a small cloud ( עב ) like a man’s palm.” Thus Rashi explains that here, עב refers to the thickness ( עובי ) of the cloud. This is ערפל , which is thicker than an ordinary cloud.

העלות הענן — Understand this as the Targum does: the departure (more lit., the raising itself). Similar is, (v. 21): תעלה הענן which means “when the cloud raised itself” (departed; in both cases the verbs are Niphal). It would not be correct to have written in these passages ולפי עֲלוֹת הענן and וְעָלָה הענן (the verbs in the Kal), because this would not be an expression denoting departure, but “springing forth” and “rising”, just as, (1 Kings 18:44): “Behold a little cloud as small as a man’s hand rises (עלה) from the sea."

Over the clouds Heb. כפים, over the clouds. Similarly (Lam. 3:41), “Let us lift our heart to the clouds (כפים),” based on (I Kings 18:44), “...a cloud as small as a man’s palm (ככף).” But our Rabbis said (Taanith 7b): Because of the sin of (the robbery of) the hands He covers the rain The rain is withheld.

Let us uplift our hearts together with our hands. When we lift up our hands to heaven let us also lift up our hearts with them to return, to bring back our hearts before the Omnipresent, Blessed is He. Another explanation: “With our hands.” אֶל כַּפָּיִם means] to the clouds, to heaven, as [Scripture] states, “There is a cloud as small as a man’s palm, rising.”³¹I Melochim 18:44. And similarly, “Over the clouds He covers the rain.”³²Iyov 36:32. But the Midrash of our Rabbis [states], “Let us uplift our hearts” sincerely to the Holy One, Blessed Is He, like a person who washes his hands to clean them, casts from his hands all contamination, for “he who confesses and abandons will obtain mercy,” but he who confesses but does not abandon [his sins] is like one who [is ritually impure who] immerses himself while holding a[n impure] creeping animal in his hand.³³Until he casts it away he will not become ritually pure. See Rashi in Maseches Ta’anis 16a.