The Relationship Between the Boreal Summer Intraseasonal Oscillation and Eastern US Extreme Heat Events

We show that the boreal summer intraseasonal oscillation (BSISO), a north/northeastward propagating summertime expression of the intraseasonal oscillation, is significantly suppressed as early as seventy days prior to Eastern US heat waves. Sea surface temperature anomalies that appear in the extratropical Pacific following weak BSISO activity are consistent with those that have been shown to be predictive of Eastern US heat waves. We also show that variability of the Asian monsoon system is significantly correlated with Eastern US heat waves at various lags.