2025-2026 ENSO

[donsutherland1]

This morning's preliminary value of the PNA was +0.707. That's the highest the PNA has been since November 20, 2025 when the PNA reached +0.738.  The PNA will remain positive for several more days before it is forecast to go somewhat negative for a short period of time. Afterward, the GEFS show the PNA rebounding. It remains plausible that a regime change (20+ days where the PNA>0 during the January 12-February 11 period or the 30-day period following the end of the recent long-duration PNA- regime) can occur. 

If so, perhaps the best opportunity for a moderate or larger snowstorm in the Middle Atlantic Region or Northeast could be in the January 25-February 15 timeframe. For such potential to be realized, the synoptic pieces would need to become available. So far, the subtropical jet has been largely quiet this winter. Should the forecast strong WWB materialize, that could lead to the subtropical jet's becoming more active across the southern tier of the U.S. some 10-14 days later. Whether that would align during a favorable longwave pattern remains to be seen. 

In the near-term, lighter snows are likely in parts of the Great Lakes Region and Northeast. The lake effect belts could see greater snowfalls, especially as Arctic air could try to get involved next week.

[Stormchaserchuck1]

[anthonymm]

Need a turn around with a KU in late january or february or else we’re not getting to seasonable snowfall. As bluewave said we need a regionwide 12”+ to have a chance at it. To give you an idea of how hard it is to get 25+” now, even if cpark got a 1’ snowstorm and nothing else this winter, they still wouldn’t reach average.