Combining GFS and ECM yields a heavy rain weather pattern evolving this week and extending into next week yielding 7+ inches of rain in East Texas to Southwest Arkansas and Northwest Louisiana. The forecast is made increasingly convincing by a potentially eastward shifting active Madden Julian oscillation (MJO) as forecast by GFS.

The NEW relative SSTA analysis across the Pacific basin reveals neutral ENSO as measured within the Nino34 SSTA region. Conversely, the standard global SSTA analysis reveals moderate El Nino has formed. As of late April, multivariate ENSO index was -0.6, indicating a lingering La Nina climate.

We are experiencing elements of the ENSO springtime predictability barrier, specifically, lack of a sustained atmosphere-to-ocean link to force an El Nino climate. The equatorial oceanic warming is there but the atmospheric reflection lags.

El Nino onset helps to inspire sharp upper-level low-pressure troughs in the subtropics to take advantage of the much warmer than normal Southeast Pacific, Gulf of Mexico, and tropical East Pacific SSTA patterns causing widespread low latitude heavy rains. Latent heat release poleward warms the atmosphere near the U.S./Canada border causing a warmer/drier pattern for the Northern U.S. later this month.