| Test Z | Q | Change/30 years | |
| Abha | −2.46* | −0.03 | −0.9 |
| Jeddah | −1.07 | −0.01 | −0.3 |
| Dammam | −0.57 | −0.01 | −0.3 |
| Tabouk | −3.43** | −0.05 | −1.5 |
| Riyadh | −1.53 | −0.02 | −0.6 |
| Tmean | −2.21* | −0.02 | −0.6 |