It may be hard to believe it with today’s weather, but we are only about 63 days away from the official start of winter.
Temperatures to start this week have been nearing 20 degrees above normal. In fact, it is quite rare for us to see temperatures in the 80s this late in the season. The latest date on record to hit 85 degrees or higher in Dayton was on Oct. 21, 1953. While it doesn’t look like we will break that record this year, our monthly average temperatures have been above normal for the last 5 months with one of the most humid summers on record.
As many of you know, we had forecast a warmer than average summer thanks to the development of a strong El Nino pattern. El Nino is a weather pattern that is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific. But by late summer, the El Nino pattern ended with ocean waters cooling in this region. While this hasn’t meant much change in our weather pattern as of yet, it appears the development of La Nino, or cooler than average ocean water in the equatorial Pacific, could begin to show its influence in the coming months.
Computer model simulations that forecasters have been watching indicated a strong La Nina could develop by this winter. However, those models now have had some varying results making the forecast for the coming winter a bit trickier. So what do we know about the coming winter?
First, we will no longer have the influence of El Nino which kept temperatures above normal and snowfall below normal last winter. If La Nina does indeed develop, then it is likely after our currently dry fall, moisture may become more abundant as we head into winter. This could mean increases in either rainfall or snowfall compared to last winter.
Another area we will be watching closely is actually the ocean water temperatures off the Pacific Northwest of the United States. Currently, this area is seeing much warmer than average water temperatures. If this were to continue into the winter, this can force a stronger ridge in the jet stream across the western U.S. into western Canada. This ridge would translate into a trough, or depression in the jet stream across the eastern United States. This type of jet stream flow would likely lead to a colder, unsettled pattern for the Great Lakes and Ohio Valley.
Lake effect snow may also be more of a problem, especially the first half of the winter. The waters of the Great Lakes are quite warm after such a warm summer and fall. Depending on wind flow, this could increase our wintry weather.
The bottom line is that this winter will most certainly be more typical Ohio winter than what we saw last year. That means we can expect more snow and more cold. How bad this coming winter will be may be more of a matter of perspective than that of reality. While this past winter wasn’t too bad, many still haven’t forgotten the “polar vortex” winters of 2014 and 2015.
Eric Elwell is WHIO StormCenter 7 Chief Meteorologist. Contact him at firstname.lastname@example.org or follow him on Facebook and Twitter.