Skillful wintertime, intraseasonal North American temperature forecasts based on the state of ENSO and the MJO

Previous work has shown that the combined influence of the El Niño-Southern Oscillation (ENSO) and Madden-Julian Oscillation (MJO) significantly impacts the wintertime circulation over North America for lead times at least up to four weeks, which suggests that both the MJO and ENSO may prove beneficial for generating a seamless prediction link between short-range deterministic forecasts and longer-range seasonal forecasts. To test the feasibility of this link, we generate wintertime (December – March) probabilistic two-meter temperature (T2m) forecasts over North America solely on the basis of the linear trend and statistical relationships with the initial state of the MJO and ENSO. Overall, we find that such forecasts exhibit substantial skill for some regions and some initial states of the MJO and ENSO out to a lead time of approximately four weeks. In addition we find that that the primary ENSO T2m influence regions are nearly orthogonal to the primary MJO T2m influence regions, which suggests that the MJO and ENSO generally excite different members within the continuum of large-scale atmospheric teleconnection patterns. The strong forecast skill scores for some regions and initial states confirm the promise that information from the MJO and ENSO may offer forecasts of opportunity for extreme temperatures in weeks 3 and 4, which extend beyond the current extended range outlooks of the National Oceanic and Atmospheric Association Climate Prediction Center, and an intraseasonal link to longer-range probabilistic forecasts.