Some initial thoughts on Teh's comment:
1- Last time I checked, Saudi Arabia was located in the northern hemisphere. Maybe the US have the power to shift it some thousand of kilometers down south. You never know these days...
2- Physics work the same but you need a temperature range, right? That was what the OP was asking.
Regarding the OP's question, I couldn't find in the SBC any indication of temperature ranges either. However, the Zamil Steel design Manual provides the following temperature variation ranges for design (in ºK) (you can find the manual easily on google):
Jeddah: 20.0
Jizan: 20.0
Alwajh: 25.0
Yanbu: 25.0
Dammam: 30.0
Madina: 30.0
Najran: 30.0
Khamis Mushait: 35.0
Riyadh: 35.0
Taif: 40.0
Tabouk: 40.0
Hail: 40.0
Additionally, I found some project-specific documents on Scribd which present the environmental temperature loads to used in Saudi Arabia. These could be a starting point for your design. I can't disclose the direct links for copyright reasons, but I think you'll find them pretty easily on a google search as well. These documents point to the following thermal loads due to environmental conditions:
- temperature range from a minimum of 0°C to a maximum of 50°C;
- in direct sunlight, a uniform temperature variation of 15ºC above ambient temperature and a temperature gradient of +25ºC and -15ºC.
These requirements need to be taken carefully as they seem appropriate mostly for concrete structures (for unprotected steel structures in my area (southern Europe) it is usual to consider a higher uniform temperature variation range (+35ºC and -25ºC), so these numbers may be off target).
The following links may prove to be useful as well:
I hope it helps to somehow lead you in the right direction.