Vernal equinox marks onset of khamsini weather conditions

AMMAN — The vernal equinox took place on Thursday, marking the end of winter and the beginning of spring in the northern hemisphere, according to the Jordan Meteorological Department (JMD).

On the first day of spring the sun crosses directly over the equator and day and night are of equal duration, meteorologist Saed Taha said on Thursday.

“The vernal equinox means the start of spring in the northern hemisphere and the start of the autumn in the southern hemisphere. Locally, it also marks the onset of khamsini weather conditions,” Taha told The Jordan Times.

The name is derived from “khamsin” — meaning 50 in Arabic — because it usually occurs during a 50-day time frame, from March 20 through May 9 or 10.

During this period, the Kingdom experiences multiple depressions bringing dusty and warm weather, the JMD meteorologist noted.

Khamsini weather conditions affect the eastern part of the Mediterranean an average of once a week. The hot, sand-laden winds, originating from the Atlas Mountains in north Africa, annually move east of the Mediterranean Sea around this time of year and are usually preceded by unseasonably high temperatures and dusty conditions.

Maximum temperatures during spring range between 22ºC and 27ºC, but gradually increase to 30.8ºC when summer starts on June 21, marking the longest day and shortest night during the year, according to the JMD.

Taha underscored that although winter ended on Thursday, rain is still expected during khamsini depressions.

“The period between March and early May brings 7 per cent of the country’s long-term annual average rainfall of 8 billion cubic metres,” he said, noting that in addition to the khamsini depressions, the country usually witnesses unstable weather conditions, which bring high temperatures and rain.

Unstable weather is forecast to affect the country on Sunday, when it will be warm with temperatures in Amman ranging between a high of 22ºC during the day and a low of 10ºC at night.

On Sunday night, clouds will start to form and scattered showers are expected in the southern and eastern regions, according to Taha, who added that showers are also forecast for Monday.