Formation of tower-like clouds at mid-levels hence their sub-name castellanus. The first thumbnail is another photo of such clouds taken an hour earlier. Some of these clouds have even developed anvil-like features at their tops resembling mini mid-level cumulonimbus clouds. At first, the weather situation that caused such clouds formation was very unclear but upon comparing a close-up of the pressure at 500mb and the visible satellite image taken at that time, it was noticed that the various shortwaves with the 590dam line were the cause of enhanced instability hence forcing these clouds to form by causing parcels of air to rise upwards and cool down. The close-up of 500mb pressure and the satellite image can be found by clicking the second and third thumbnails respectively. The fourth thumbnail of the weather sounding confirmed the instability at the mid-levels of the atmosphere along with a warm and moist airmass at the 550mb level. The distant low pressure system over Northern Africa could have also contributed to the cloud formation. Due to this weather situation some rain was observed on this day and the following day being measured at less than 0.2mm.