Russell, North Carolina State University, "The Role of Convection in African Easterly Wave
Weather systems likely to influence the country are the tail end of the cold front, intertropical convergence zone, easterly wave
, ridge of high pressure area, the easterlies and three to five tropical cyclone occurrences.
An official of PMD told that this rain would not be a part of monsoonal activity which is caused by easterly wave
but it would be the result of westerly trough present in the upper air.
An easterly wave
is a slowly moving trough of low pressure within the belt of the tropical easterly (trade) winds.
The synoptic situation says that the easterly wave
is penetrating into upper areas of the country.
Replying a query regarding pre-monsoon, she said now the westerly waves are bringing rains in the upper parts however, monsoon is due to easterly waves
which would develop after subsiding these systems.
Mindanao, meanwhile, will experience scattered rainshowers and thunderstorms due to the northward migration of intertropical convergence zone or passage of easterly waves
, Pagasa said.
These are easterly waves
and are sometimes referred to as "inverted troughs," since they are strongest deep in the tropics and weakest at their poleward tips.
The application to the Caribbean region indicates a corridor of favorable conditions in the central Caribbean, possibly promoted by the presence of easterly waves
, and a southern unfavorable zone that shelters the Venezuelan coast from hurricane impact.
These easterly waves
often serve as the `seedling' circulations for a large proportion of tropical cyclones over the North Atlantic.
During this season, moisture associated with tropical easterly waves
(Fuller and Stensrud 2000; Favors and Abatzoglou 2013) and remnant Pacific tropical cyclones (Corbosiero et al.
Showers and broken to overcast clouds are common within and near easterly waves
, and during the warm season easterly waves
can deteriorate into tropical depressions and full-blown tropical storms.