Formation of altocumulus clouds in an unseasonable warm conveyor belt full of clouds as seen from the satellite image (1st thumbnail). Due to the arrival of a cold front late in the day (2nd thumbnail), this resulted in an uneven mixing of the warm and cold airmass hence puffs in the altocumulus cloud cover. These are normally white or grey but due to the setting sun lightening their bases and suspended desert sand these appeared yellowish. The third thumbnail show the weather sounding at the time indicating both high-level and mid-level clouds. This was the reason that no blue sky was seen within the space created by the altocumulus clouds below. The 4th thumbnail shows the unusual undulation of wind at 500mb height, more typical of the Spring season. This was the primary reason behind the creation of the warm conveyor belt hence the creation of the photographed clouds. An interesting note was the Spain expirienced below freezing temperatures while temperatures over 30 Degrees Celcius was reached widely over the east of Northern Africa and possibly in a spot over Greece.