Wx4cast: Early 2025-2026 Winter Thoughts.

I really didn't post anything earlier today on our current pattern over the Northeast. The reason is nothing has really changed and there is really nothing going on to post about.

The last several days have been mostly dry with warm temperatures and low to moderate levels of humidity. The next few days Should stay mostly dry with only a chance for a few isolated showers or rogue thunderstorms popping up. Saturday and Sunday will be more of the same except we will see an increased southern flow that will really start to spike our temperatures and raise our humidity levels. By Monday the heat and humidity is going to lead to oppressive conditions This will continue into Tuesday ahead of an approaching cold front. Sunday Monday and Tuesday is likely going to be a region wide official heat wave with air temperatures in the 90s and 100s. Tuesday should stay mainly dry But later in the day there could be a few showers over western parts of the region. Wednesday into Thursday the cold front will be moving across the region bringing scattered rain showers and thunderstorms Some of these thunderstorms could be strong to severe. On Friday the cold front will be pushing east taking the heat and humidity with it and hopefully it will clear us completely out from all this wildfire smoke we've been dealing with.

Winter thoughts:

It's early August. So it's way too early for a detailed winter outlook. But let's take a look at some possible implications of what we are currently seeing, that could impact how the upcoming winter unfolds.

Winter is still several months away. But we are in August, that time of year when the general pattern starts to change as we descend towards winter.

The 850mb temperature anomaly. Courtesy of tropical tidbits

Courtesy tropical tidbits.

The North Atlantic:

SSTs in the North Atlantic are another very important long range forecasting tool

Over the last several years the North Atlantic has been on a warming trend But now that trend looks to be starting to reverse as we look to be headng into a cooler trend.

Courtesy tropical tidbits.

The Pacific:

The El Nino Southern Oscillation (ENSO). The ENSO deals with sea surface temperature anomalies in the eastern tropical pacific. The ENSO is a key long range teleconnection. The ENSO is still in a neutral phase; but it looks to be trying to shift towards a weak La Nina as we get closer to the 2025-2026 winter. So the upcoming winter will probably end up being either neutral or a weak La Nina.

Courtesy of tropical tidbits

There are subtle differences in the winter-time pattern between a cold neutral phase and a weak La Nina phase.

During a weak La Nina, many times we see strong troughing over the western US into western Canada. There is also a tendency for some troughing in the Great Lakes into the Northeast. During a weak la Nina the troughing in the Northeast isn't really extra deep it is more weak to moderate in scope. There was also a tendency for a stronger Southeast ridge that can add a lot of temperature volatility to the pattern.

During a cold ENSO neutral phase, There is a greater chance for a strong ridge over the western US and Canada. With a greater chance for a strong trough to develop in the North Central US into the Great Lakes , Northeastern US and Middle Atlantic region. The strong troughing over the Northeast can limit the impacts from the Southeast ridge keeping it more at bay. On average ENSO neutral conditions increases the odds for a much colder than average winter here in Northeast and northern Middle Atlantic. Some of our snowiest winters occurred during ENSO neutral.

Images courtesy of tropical tidbits

We see the Sea surface temperatures (SST) west of South America in the eastern equatorial Pacific looking like their cooling. Getting into winter, we also will have generally cool air over California into North America. Both of these taken in conjunction with each other leads to a weaker less dynamic subtropical jet over the winter. There is no big temperature contrast to really drive it. A weaker overall subtropical jet means There is a greater chance for the subtropical jet to be more in the way of inactive. So there is less of a chance for storms to develop that could come up the Coast.

Looking at the SST off the Pacific Northwest, in the Gulf of Alaska and across the North Pacific we see lot very warm water. This means we're in a positive Pacific North American Pattern (PNA). Typically a positive PNA leads to above average chances for a cooler than average winter over the eastern United States. This would also lead to a better chance for the polar jet to be active, with the possibility of several systems moving along it out of the pacific moving over the Pacific Northwest into Canada and then maybe dropping down into the central and eastern US.

But this winter could be a little different. So with those very warm SST in the North Pacific, taken with the general idea of cooler air sitting over Canada and Alaska this winter, means we would have a big temperature contrast between the two. This could lead to a much stronger Polar jet. If the polar jet becomes very strong, it could help lock a lot of that Arctic air up over or near the North Pole. Which might limit the amount of cold air available into the CONUS resulting in a possibly overall warmer than average winter.

The quasi biannual oscillation QBO:

Image credit NASA GSFC

Currently we have transitioned from a westerly QBO to an easterly QBO. This will have some implications for our winter season. But nowhere near as much as the ENSO and North Atlantic SSTs. When the QBO is in an easterly phase we tend to see more in the way of ridging in the western US and a greater chance for overall troughing in the eastern US.

Arctic sea ice:

Image credit NASA GSFC Earth Division

Arctic sea ice extent is a very important teleconnection. As there is a correlation between it and the winter time pattern over North America.

Arctic sea ice extent for august 2024.

Image credit The national snow and ice data center

Arctic sea ice extent for August 2025.

Images courtesy of the national snow and ice data center

Looking at the charts. We can see sea ice extent is a little greater than it was at this time last year. But the ice does look like it 's closer to the Coast of north Alaska. Based on the long-term 30 year average Arctic ice extent reaches its summer time minimum around the middle of September. So we still have a few weeks of melting to go before we reach the 2025 minimum extent. After that we will start to build on the extent of the ice cover If it can build fast enough It could have implications for the upcoming winter.

The greater the sea ice extent is in the Bering Sea and the Arctic Ocean the lower the chance there is for the cold air that forms in Siberia during the fall and winter will modify as it moves across Alaska, Western Canada into the lower 48. For the 20252026 winter Arctic sea ice extent is going to be a wild card.

Great Lakes water temperature

Image credit NOAA Great Lakes environmental research laboratory

All five Great lakes are extremely warm right now. Some areas are even at record high water temperature.

Last winter saw a lot of snow in the lake effect Snowbelts. With the temperatures in the lakes as warm as they are the 2025-2026 winter could see more of the same.Right now the table is being set for possibly a very heavy Lake effect snow winter. But a lot of that will depend on how the polar jet behaves and the overall general storm track.

Siberian snowfall:

Image credit Rutgers University climate snow lab

It's still too early to talk about Siberian snowfall extent. There is a link to snowfall extent in Siberia during the month of October and the winter time pattern in North America. If there's a lot of snow in Siberia during October. It can be a signal for a cold winter here in the eastern US. Temperatures over Siberia over the next 7-14 days Do look to be below average. So this could add a chance for snow to accumulate. So this is another wild card that we have to wait to see how it plays out over the next couple of months.

Based on the current data some of the teleconnection signals are conflicted. But the overall setup seems to be pointing towards an average to a slightly cooler than average December to March time frame.

Here are NOAA's current thoughts on the upcoming winter