Jordan weather main characteristic is the contrast between a rather rainy season from November to April and very dry weather during the rest of the year. Jordan weather is a Mediterranean weather, as the summers are hot and dry, and the winters are cool and sporadically rainy. In inland, the seasonal contrasts in temperature are more noticeable and the precipitation is lower.
During the summer months, Jordan weather atmospheric pressures are relatively consistent, whereas during winter a series of marked low pressure areas occurs and cold fronts are being created. These cyclonic turbulences normally move eastward from over the Mediterranean Sea several times a month and produce sporadic precipitation.
Most of the East Bank, which can be characterized as a dry dessert or a steppe region, receives less than 12 cm of rain a year. The precipitation in the highlands east of the Jordan Valley, increases to around 30 cm in the south and 50 cm or more in the north. The Jordan Valley forms a narrow climatic zone that receives up to 30 cm of rain throughout the year in the north, and in the south the rainfall decreases to less than 12 cm.
The long summer in Jordan reaches its peak during August, which is the hottest month. January is usually the coldest month of the year. In the summer, the temperatures vary a lot during the day, especially as you move inland and away from the Mediterranean seacoast. Furthermore, during daytime in the summer the temperature average is 32 C and often exceeds 36 C. Whereas, the winter months, from November to April, are moderately cold, at an approximate average 13 C. Frost is not rare during the winter, and it snowfall is possible in Amman.
For a month before and after the summer dry season, hot dry winds (khamsin) from the desert, drawn by low pressure bring dust and sand clouds into Jordan. The arrival of khamsin is signified by a foggy sky, a falling barometer, and a decrease in humidity to about 10%. Jordan weather temperature may have a 10 C to 15 C rise in just a few hours. These windstorms normally last approximately for day and cause many problems, especially to crops.
The shammal, another wind which comes from the north or northwest, usually at intervals between June and September, is remarkably steady during daytime. However Jordan weather at night, shammal may blow for up to 9 days out of 10. The shammal is a dry continental mass of polar air that is warmed as it passes over the Eurasian landmass. The dryness that comes with this wind, allows heating of the earth's surface by the sun, which results in high daytime temperatures that drop after sunset.
