Most wargames generals tend top ignore weather, but the following is a startling illustration of the power of weather on the battlefield:
 

The following is closely based on a passage in The Cambridge Ancient History, the essay was written by a Mr Hackforth.
 

In 341BC the Carthaginians sent a powerful citizen force to Sicily, in order to prevent the further loss of colonial holdings to the Corinthian general and liberator of Sicily, Timoleon. We take up the narrative on page 296: The battle was fought on the bank of the Crimisus, not far from Segesta. It resulted in a decisive victory for the Greeks, which was due to several causes: the presence of a heavy mist enabled Timoleon to surprise the enemy by an attack from high ground; a violent thunderstorm came on, which drove rain and hail straight in the face of the Carthaginians; and the heavily-armed warriors of the Sacred Band, who bore the brunt of the fighting, found themselves at a great disadvantage in face of the superior mobility of the Greek infantry; the torrent of rain rendered their equipment still heavier, and as the plain rapidly became a morass owing to the overflowing of the river and to the swollen streams which swirled down from the hillside they found it increasingly difficult to move. Large numbers were swept away down stream, the rest were slain or put to flight . As many as 10000 are said to have fallen, including the whole of the Sacred Band; heaven, in a very literal sense, had aided the Corinthian leader in this great battle, which was fought in mid-June 341: the spoils of the enemy's armour were very rich, and fine trophies were sent to adorn the temples of Corinth and to add to her renown.
 

Taken from: The Cambridge Ancient History Volume VI Macedon 401-301BC. 1953. University Press: Cambridge.
 

WRG 7th:

From Volume I, 1992: Army list 54 Early Carthaginian, which features the Sacred Band as Reg A HI LTS Sh @32pts 0-6.The only minimums are Libyan-African Reg C MI LTS Sh @16pts 8-24 and some Greek mercenaries Reg C MI LTS Sh @16pts 6-16, the army also has the option of taking a Numidian allied command, in which case some Numidians also become forced minimums. Timoleon was sent by Corinth as a liberator, not a conqueror, so was not supported by an army of his own, although there were some mercenary troops that accomapnied him from Greece. He would command army list 57 Syracusan, which features an incredible mixture of anything possible, the Sikels Irr C LI JLS Sh @6pts up to 12 are native to Sicily.