Did ancient Egyptians or other old African civilization knew about ice and show?
This is a great question for Egyptian language to answer. Before doing that, it's necessary to highlight the dangers of linguistic determinism (the notion that thought is totally constrained by language). Ironically, but perhaps not surprisingly, this exact concept is one of the most common examples of careless linguistic determinism in everyday life, because it appears in the popular sayings about Eskimo words for snow. The primary caveat is that linguistic evidence can only used to support the positive claim (that ancient Egyptians knew about snow). It cannot support the negative, as it would be perfectly possible to encounter snow, comprehend it as frozen precipitation, and even pack and shape it into houses, without having a single unique word for it. The ancient Egyptians might have known just about everything there is to know about snow without having the equivalent word "snow" in their lexicon.
That said, they kinda do. Beginning in the reign of Ramesses II (1279-1213 BCE) the word: π π€ππ€ππ ±π² appears in the phrase: π ππΏπ«πππ ±π³π₯ππππππππ π€ππ€ππ ±π² "in the days of rain and snow" in a text that describes a journey to Anatolia, north of Egypt.ΒΉ There's little doubt about the reading of this word (and there are many other examples), so we can be confident that π π€ππ€ππ ±π² does indeed refer to frozen water falling from the sky.
So they saw snow when they traveled to other places where snow is more common, and they even described it later back home using a single word, which suggests that it was already known. That said, there is no Egyptian word for snow. The word π π€ππ€ππ ±π² is very obviously a borrowing from a Semitic language (cf. Arabic Ψ«ΩΨ¬ "ice"/"snow"). π π€ππ€ππ ±π² is written in an alternative orthographic system (known as "group writing" or "syllabic orthography" by Egyptologists), which is often used to represent the pronunciation of foreign words.Β² Group writing is the Egyptian equivalent of spelling the word "tomato" as "toe-may-toe", i.e. it uses common orthographic sequences to spell out precisely the pronunciation of the word in a way that is marked stilted to readers, which is not the usual way of doing things in hieroglyphs.
Long story short: the ancient Egyptians encountered snow when they traveled to the mountains, adopted the local word for it into their language, and then went on knowing about it from that point forward.
See Hoch (1994) Semitic Words in Egyptian Texts of the New Kingdom and Third Intermediate Period, Β§365, pp. 264-264. As I don't have electronic access to KRI (the physical book is in a box in storage right now because of covid), I've had to reconstruct the original hieroglyphic text.
For more on group writing and how it represents spoken language, see Kilani (2019) Vocalisation in Group Writing