Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 768 | 692 | 747 | 739 | 769 | 737 |
| Tmin | 767 | 694 | 758 | 740 | 768 | 745 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 762 | 678 | 747 | 724 | 747 | 723 |
| Humidity/Visibility | 121 | 109 | 118 | 116 | 119 | 117 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 772 | 786 | 771 | 790 | 769 | 766 |
| Tmin | 767 | 770 | 747 | 763 | 739 | 761 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 750 | 771 | 750 | 773 | 750 | 749 |
| Humidity/Visibility | 120 | 129 | 130 | 129 | 128 | 120 |
Climate data is usually derived from meteorological data of a certain number of years. The actual number of recorded years may vary from only a couple to 50 years or more. The quality of climate data depends on the number of available recorded years. Fewer years means less reliable data. The standart-period for reliable climate data is 30 years. For example, the mean monthly temperature for, let's say January, would ideally calculated from a total number of 930 recorded January-days. However, the usual number of recorded days is much smaller. The table above shows the actual number of recorded days for every parameter measured. |
Al-Jizah