In general, the NCM added that the Intertropical Convergence Zone advanced toward the country is associated with an upper trough
extended from the East, with the continuity of the high and medium clouds appearance over scattered areas during the next few days.
"An extension of surface trough of low pressure over the country has been accompanied with an upper trough
," the NCM said.
An upper trough
moved towards the central parts of the Arabian Peninsula caused moderate rain over the kingdom on the 24th of February with 4.8 mm of precipitation recorded at Bahrain International Airport, 10.4 mm at Durrat Al Bahrain, 6.8 mm at Sitra Island and 2.8 mm at King Fahd Causeway.
A fast moving Atlantic low will merge with a deeper, slow-moving polar low to form a broad upper trough
over the North Sea area from March 28.
Winds with the upper trough
bring in colder air aloft, and the lifting also cools the layer.
"The upper trough
will start to move over the area Friday afternoon for slightly cooler temperatures.
An upper trough
across Bihar, Jharkhand and Gangetic West Bengal is causing heavy rains in Bankura, East and West Burdwan, East and West Midnapore, South and North 24 Parganas and Murshidabad districts, the regional MeT office said.
Caption: Figure 8: (a) The flight track in the Haituo Mountains under (red circle) upper trough
weather condition (case 1); (b) Chang Chonggou weather elements time series; (c) Xi Dazhuangke weather elements time series.
Although 300-hPa geopotential height rises everywhere in future relative to current simulations, the northern portion of the future upper trough
to the northwest of Sandy results in lessened rises there, producing an increase in westerly flow across the path of Sandy during the time of northward storm movement in the western North Atlantic (Fig.
The slowed movement saw an upper trough
form by Monday and quickly shape a core cut off from the vortex core.
The bout of bad weather affecting the country is an extension of a surface low pressure over most areas of the UAE and the Arab peninsula accompanied with an upper trough