Influence of the MJO on daily surface air temperature over Iran

The influence of the Madden‐Julian Oscillation (MJO) on surface air temperature over Iran is examined using daily data from meteorological stations from 1979–2015. Composites of daily surface air temperature anomalies are positive in MJO phases 1 and 8 and negative in MJO phases 3–4 with broader region positive tendencies also in MJO phases 2 and 7, and negative tendencies in MJO phases 5–6. This variability is associated with horizontal temperature advection, whereby the southerly (northward) winds act to heat and the northerly (southward) winds cool Iran, in association with the MJO. Further, we find that daily minimum surface air temperatures respond more strongly to the MJO than do daily maximum surface temperatures. These signals correspond to cloudy and humid conditions.