African easterly waves
E829128
African easterly waves are westward-moving atmospheric disturbances originating over Africa that often serve as the seeds for tropical storms and hurricanes in the Atlantic.
Statements (51)
| Predicate | Object |
|---|---|
| instanceOf |
atmospheric wave
ⓘ
meteorological phenomenon ⓘ synoptic-scale disturbance ⓘ |
| affects |
eastern Pacific tropical cyclone formation
ⓘ
tropical Atlantic weather patterns ⓘ |
| alternativeName |
AEWs
NERFINISHED
ⓘ
tropical waves ⓘ |
| associatedWith |
African easterly jet
NERFINISHED
ⓘ
convection ⓘ mesoscale convective systems ⓘ organized thunderstorm clusters ⓘ |
| causedBy | instability of the African easterly jet ⓘ |
| climatologicalFrequency | 20–60 per season in the Atlantic ⓘ |
| drivenBy |
African easterly jet
NERFINISHED
ⓘ
baroclinic instability ⓘ barotropic instability ⓘ |
| firstDescribedBy | Reginald E. Newell NERFINISHED ⓘ |
| firstDescribedInDecade | 1960s GENERATED ⓘ |
| formsInLayer |
lower troposphere
ⓘ
mid-troposphere ⓘ |
| formsInSeason |
Northern Hemisphere early autumn
ⓘ
Northern Hemisphere summer ⓘ |
| influences |
Atlantic hurricane activity
ⓘ
rainfall over West Africa ⓘ rainfall over the Sahel ⓘ |
| movementDirection | westward ⓘ |
| observedBy |
radiosonde data
ⓘ
reanalysis data ⓘ satellite imagery ⓘ surface observations ⓘ |
| occursInBasin |
Caribbean Sea
NERFINISHED
ⓘ
North Atlantic Ocean NERFINISHED ⓘ eastern North Pacific Ocean NERFINISHED ⓘ eastern tropical Atlantic ⓘ |
| originatesIn | Africa NERFINISHED ⓘ |
| originRegion |
Sahel
NERFINISHED
ⓘ
Sudan region NERFINISHED ⓘ |
| peakActivityMonth |
August
ⓘ
September ⓘ |
| propagationSpeed |
about 10–20 km/h
ⓘ
about 5–10 knots ⓘ about 6–12 mph ⓘ |
| roleInCyclogenesis |
precursors of hurricanes
ⓘ
precursors of tropical storms ⓘ seed disturbances for Atlantic tropical cyclones ⓘ |
| typicalAmplitude | low-level vorticity perturbation GENERATED ⓘ |
| typicalPeriod | 3–5 days ⓘ |
| typicalStructure |
ridge at low levels
ⓘ
trough at low levels ⓘ vorticity maximum near the wave trough ⓘ |
| typicalWavelength | 2000–4000 km ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.