In general, Silurian climates were warm and dry.
In Gondwana, cool to cold climatic belts encircled the South Pole.
Euramerica, containing a wide band of southern mid-latitude desert, had a hot and arid climate.
Image courtesy of C.R. Scotese, http://www.scotese.com (PALEOMAP website).
Yellow = Evaporites
Red = Calcrete deposits
Blue = Kaolinite deposits