تقييم الظروف السينوبتيكية المرافقة لموجة الحر التي أثرت على الأردن خلال الفترة 30 حزيران-6 تموز 2017

الملخص EN

This study deals with evaluating and analyzing the synoptic conditions associated with the heat wave that influenced the whole East Mediterranean (EM) region particularly Jordan during the period June 30 - July 6, 2017.

This has been conducted through analyzing both surface meteorological maps at level (1000 hpl) as well as synoptic charts at level (500 hpl).

Regarding the meteorological variables, the variation of temperature (maximum and minimum), relative humidity, dew point and the direction and the speed of the wind were followed up during the period of the heat wave.

The study has furthermore employed the Tephigram diagrams for analyzing weather circumstances and the characteristics of air mass in different atmospheric layers.

Ultimately, the severity of heat wave was estimated using heat index (HI).

The results show that the main cause of the heat wave in the East Mediterranean (EM) including Jordan during the study period (June 30 - July 6) was attributed to the Indian monsoon.

The Indian monsoon travelled towards the north-west over the Arabian Peninsula and reaches all the countries in the East Mediterranean including Jordan, Palestine, Syria and southern Turkey and causing an warm upper Ridge that increased its depth over the region during the study period.

This warm upper Ridge led to increasing the surface air temperature to around 47° C in Ghour Alsafi station and reducing the relative humidity to about 30%.

Besides, it led to increasing the air temperature at upper levels and reducing the dew point.

These weather conditions were noticed during the study period and reached their severity for three days (2- 4 July) when an extreme temperature was recorded.