Updated 09.16.23 8:16a
The pattern transition from the current cooler than normal regime to a warm September finish, compared to the norm, will get started the middle of next week. We still have several days to go with highs of 82°+ to close out the month. The pattern, as a whole, looks drier than normal. The exception to that general rule will come Sunday with scattered showers (the system that generates Sunday showers here will serve to ignite an early season ‘Nor Easter early week for the Mid Atlantic and New England. – A sign of the changing seasons) and we’re still tracking the threat of a more organized storm system in the early Week 2 period. The trend, however, has been for this being less of a player in our weather compared to a few days ago but we’ll continue to keep a close eye on things.
As we flip the page into October, the pattern drivers from this distance appear to be lining up to drive a period of cooler air as we rumble through the first 1/3 of the month. The Madden-Julian Oscillation (MJO) looks to push into Phase 6. This typically favors the warmer anomalies across the west and Plains with at least a reflection of a trough across the East Coast.
The Pacific North America pattern (PNA) and East Pacific Oscillation (EPO) are working in tandem to also favor a cooler regime across our portion of the country. It’s fair to say that we believe the longer range warm “look” will be forced to cool over the course of the next couple weeks for early October.
The dry, relatively boring regime should begin to turn more active as we close out the month and move into October. The thinking here is that we should see a resurgent wet regime the deeper into fall we go before rolling into the drier than normal predominant winter pattern.
