Daily Weather Types in February–June (1979–2016) and Temperature Variations in Tropical North Africa

AbstractThis study investigates to what extent weather types (WTs) computed over Tropical North Africa and the tropical North Atlantic (40°W–40°E, 0°–30°N) are relevant for documenting intraseasonal and interannual temperature variability in Tropical North Africa (West of 37°E, 2°–27°N). Nine WTs are extracted using clustering analysis of the daily anomalies of sea-level pressure and low-level 925-hPa winds from two reanalyses (NCEP-DOE and ERAInterim) from 1979 to 2016. The analyses are carried out separately for February–March and April–June, when temperatures reach their annual peak across most of the region. The WT patterns mix the effect of different multiscale phenomena including the extra-tropical Rossby waves traveling on the northern edge of the domain (and partly related to the North Atlantic Oscillation), the Madden-Julian Oscillation and the Kelvin waves in the subequatorial zone. For eachWT, warm (cold) minimum (TN) and maximum (TX) daily temperature anomalies tend to be systematically locate...