“Normals” for January includes highs in the middle 30s and lows in the upper 10s to lower 20s across central Indiana. Early to middle parts of next week are forecast to feature highs in the upper 20s to around 30 and lows in the middle 10s. Yes, these temperatures will challenge records as a truly impressive arctic invasion claims next week’s weather headlines.
A lot of this has to do with the sea surface temperature (SST) configuration across the northern Pacific. We’ve been focusing in on the warmer anomalies across the north and northeastern Pacific and tendency for this to drive a persistent ridge across NW NA since late summer. That persistent NW NA ridge leads to a persistent trough downstream and the associated cold pattern we’re now looking at. As our Winter Outlook suggests, we think this overall pattern repeats itself throughout the majority of the months ahead.
As we look more “immediate term,” what do teleconnections and the MJO tell us about the overall pattern moving past the middle of November? Well, to start, the highly amplified MJO is forecast to roll into Phase 7 around mid-month. This suggests the colder than normal pattern persists.
The EPO is forecast to remain negative while the PNA remains positive into and through the mid month period. Both argue for continued cold.
To no surprise, the latest long range data continues to drill unseasonably cold air south into our portion of the country and a large majority of the eastern portion of the Lower 48 in the Weeks 2-3 time period. Snow opportunities will undoubtedly follow with this kind of pattern.
Buckle up…