Latest drought update
The Northeast and Middle Atlantic have been experiencing a prolonged drought that has lasted for several months.
Rainfall this week across the region has been a case of the have and have not. Areas that saw meaningful rainfall saw some improvement in the over all drought conditions. However areas that saw limited rainfall saw drought conditions remain the same or get worse.
State drought declarations
The US drought monitor released yesterday, shows that 12% of the Northeast is in extreme drought conditions, 22% is experiencing severe drought, 29% in moderate drought and 32% considered abnormally dry. Compared to 12%, 22%, 30% and 32% respectively last week.
The drought has led to wide ranging implications across the region.
The Northeast and Middle Atlantic region has been experiencing degraded water quality, extremely low water levels and stream flow, many wells running dry, especially those that are dug or stream fed. The drought has also been devastating for the Christmas tree industry along with this year's pumpkin crop. So be prepared To pay a lot more for these holiday staples. Farmers in general have seen greatly reduced crop yields.
Here is a look 7 day rainfall forecast For the Northeast and northern Middle Atlantic region.
Winter 2025-2026
The winter pattern continues to evolve we've just gotten over another major winter storm that hit Alaska. This is going to end up dropping south and east and become a major driver for next week's weather.
As the jet stream slowly continues to push south We are seeing stronger storms Move into Alaska and drop down into North America. As the cold continues to build south It is going to push the storm track south and encourage more of these stronger storms to move Into the Continental US.
Looking at the euro chart We can see we have another strong storm that's dropping down towards British Columbia With another storm Dropping out of Asia heading towards The gulf of Alaska. The one dropping towards British Columbia is going to bring a lot of heavy snow to that region. Looking at the chart below We can see that blocking building up over the arctic This is the reason for that cold moving south along with the adjustment in the storm track. I expect this pattern to continue to evolve and stay active over Canada and the northern half of the CONUS for the next few weeks.
Current global sea surface temperature anomalies
Sea surface temperature anomalies for last October
Snow cover and arctic sea ice extent
Snow cover across Siberia is well about above average for this point in October. Arctic sea ice extent is also larger than last year in fact larger than the last several years. It is also much closer to the north coast of Alaska than it has been over the last few years.
This all adds up to what I've been saying to a greater chance for cold air to migrate out of Siberia move across the Pole, Increasing our chances for cold across Canada and down here into the Lower 48.
El nino southern oscillation (La Nina):
The climate prediction center placed us under a la Nina watch a little bit ago. As I've been saying This La Nina should be weak; which means the average index in region 3.4 will be running -0.5° C.to -0.9° C. Currently the El Nino index in Nino region 3.4 is running right around -0.3° C. that means the La Nina is still running very weak.
As I've been saying this should be a very short lived la Nina. We will likely start heading back towards ENSO neutral in January. Then maybe heading towards El Nino over next summer.
During Neutral to weak La Nina the polar jet typically dips farther south into the conus. This allows that colder arctic air bottled up to the north to be able to slide south and provide cold air across the northern Plains , Midwest, Great Lakes and Northeast and into the northern Mid-Atlantic. This is all good if you're a snow lover because it takes cold to bring the snow
The Eastern Pacific Oscillation (EPO) or as it's now called The east pacific -north pacific Pattern (EP/NP):
Right now we're in a positive EPO The indicators are pointing to the idea that this is going to shift to a negative EPO. This is important due to a negative EPO promoting rigging in the west And more in the way of general troughing here in the east, This adds to the idea I've been talking about with this being a winter that favors more cold than not.
The way the EPO is behaving it is going to keep our pattern very active and energized.
The Quasi Biennial Oscillation (QBO):
The Pacific North American pattern (PNA):
As I've been saying over the last couple of months those very warm sea surface temperatures in the north pacific are going to be a major factor in how this winter transpires.
As I've already said in previous post This warm blob in the north pacific is going to promote strong rigid into the gulf of Alaska over the west coast And allow for general groundBreaking to set up here in the eastern half of the US. It is also going to help keep that polar jet very variable and wavy due to it helping to keep the polar vortex overall weaker than we would normally see. Leading to a greater chance for cold air intrusions.
Tropical Northern Hemisphere Pattern (TNH):
This pattern is most predominant during December through February. It has a major impact on the position and strength of the pacific jet. In this way it acts as a gatekeeper On how much pacific moisture can make it into North America. It's also a player in the strength and position the Hudson Bay low. The Hudson bay low is a large area of low pressure that typically sets up over the Hudson Bay during the winter months, from late fall into early spring.
The Hudson bay low is a very important factor in how cold and stormy winters here in northeast and northern Middle Atlantic can become. It can help send cold air out of Canada into the Plains, Great Lakes and Northeast region of the United States. But it can also act as a block in the northern Flow that can redirect the storm track further south into the northern half of the United States. So the TNH's impact on how strong the Hudson bay low can become and where it will end up setting up; will be a big factor in how this winter goes.
When the TNH is positive we tend to see ridgeing in the Gulf of Alaska and down through the western half of the United States This in turn leads to troughing over the eastern United States. So of course, when the TNH is negative the pattern reverses
Years that saw the TNH in a positive orientation saw a greater tendency for cooler than average conditions here in the Northeast and Middle Atlantic and especially back into the Great Lakes.
Great Lakes:
The lakes are very warm for mid October. Temperatures across the great lakes are running 2-7°F above average for this time of year.
Image credit Great Lakes environmental research laboratory
Last winter the lake effect snowbelt regions had an epic winter. With annual seasonal snowfall amounts ending well above average. With the water as warm as it is When that colder air starts moving across them We could see another very active land effect winter in the snow belts.Analogues
1990-1991, 2006-2007, 2008-2009, 2013-2014, 2017-2018, 2024-2025
These analogues are based on winters that started with a positive TNH.
October 2006 sea surface temperature (SST) anomalies
October 2008 SST anomalies
October 2013 SST anomalies
October 2017 SST anomalies
I posted the October 2024 SST anomaly image further up the page.
Here is the temperature and precipitation composites Involving these five analogue seasons
Another set of maps
what does this mean?
During a weak La Nina/neutral ENSO, the northeast and Middle Atlantic tend to see above average precipitation amounts. This is due to the fact of how the polar jet and the subtropical jet end up phasing (interacting) to varying degrees. So depending on the timing of cold air and orientation of the storm track at that time will determine precipitation type, northern areas favor more in the way of snow while southern areas would favor a chance for some rain events.
Given what I'm seeing in this evolving pattern, this winter is going to favor More in the way of cold and a better chance for snowy events. The northern half of the Northeast general snowfall amount should end up above average from December through February. South of there average to slightly below average snowfall amounts for the season. But of course that is going to depend and the timing of the storms moving along the storm track.
With the way the pattern is shaping up and as warm as the Great Lakes are; I believe this is going to be another very active and busy lake effect snow season.
The way the pattern looks to evolve with the polar and subtropical jets. It looks like it's going to favor a storm track through the Midwest, Great Lakes into the Northeast. But I can also see a chance for some coastal/nor 'easter type storms.
That's it for now.
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