January 5th, 2025

 

Here’s a look at the current frontal chart and radar imagery

Lake effect continues to fall downwind of Lake Erie and Lake Ontario, during the course of today into tonight, the lake snows should dissipate. The areas hardest hit by this 4-day lake effect event have been across northern Onida and southern Lewis Counties where 60 to near 72 inches have fallen. The lake snowbelts have been getting hit hard this winter, just as the winter outlook said they would.

We have our storm approaching. The dry air over New York State and New England will cause a sharp cut off. There isn’t much change from what I said yesterday

The track and setup will keep the heaviest snows near the Mason Dixon line and points South. For southern New Jersey, Maryland, Delaware and Southern Pennsylvania, including Washington, D.C. and Baltimore 4-12 inches with southern part of Maryland and Delaware having the best chance of seeing spots of over a foot. North of there up across the middle of Pennsylvania, including Pittsburgh through central Pennsylvania into Central New Jersey a general 2-4 inches, for northern Pennsylvania a chance for 1-2 inches. With the into the New York State Southern Tier having a chance for a trace to around an inch. For far southern Connecticut, New York City and Long Island, you’re on the fringe, but you could see some snow showers/flurries with a chance for a trace to an inch possible. Each of these zones could have areas that see higher amounts. But generally, this is how it is looking. There is still a chance for accumulating ice across southern Maryland and Delaware with an accretion of 0.10 to 0.33 of an inch. How much Ice will be dependent on how much warm air pushes in from the south and how strong ocean flow is coming in from the east. North of these areas little to no snow is expected.

Timing looks to be generally the same as I laid out yesterday.

The storm will be exiting the region Monday night into Tuesday. Then Arctic High pressure will build in, bringing much colder temperatures as a piece of the polar vortex looks to drop south for much of the week. We will have a few shortwaves moving through that could kick off a few snow showers and flurries. But the most likely spots for any accumulations will be in the higher elevations of New York State and Northern into Central New England.

The Euro and GFS model images come from Tropical Tidbits.

Behind this storm on Tuesday, there is a chance for some energy to develop in the Rockies. From here it looks to track south and east and interact with a disturbance in the southern stream over the Southwest. The polar front will be down near the Gulf Coast, so this will likely track along that. From there it could track out to sea, or it could move off the Southeast Coast and track toward New England later Friday into Saturday. Right now, this is something to watch, with no guarantee that this will become a nor’easter. Who sees what will depend on the exact track and how strong the storm is, We have a week to see if it develops. 

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January 4th, 2025

 

A quick look at the weekend, and my latest thoughts on the next storm. 

Here’s a look at the current frontal chart, radar and satellite imagery

 

Today is cold and breezy, making for very cold windchills.

Lake Effect snow is continuing to fall South and east of Lake Ontario, as the winds shift to the west, the lake band will move north into the Mohawk Valley, then over areas east of the lake. By Tonight it will be up over the Southern Tug Hill where it will stay into Sunday morning, then the band will shift back south weakening and eventually dissipating Sunday night.  The areas under the most persistent bands will see another 1-2 feet, with localized areas higher than that.

Our Sunday night Monday storm is starting to develop, later today/night it will be over over the southern Plains, then this will deepen as it continues East. Right now, snow will be moving into the Middle Atlantic Sunday evening, say around 8 PM. This will push north and make it into Southern Pennsylvania 11 PM to 1 AM.

This could bring a stripe of heavy snow along the Mason–Dixon line. Far southern Pennsylvania Maryland, Delaware, and southern New Jersey could see 4-12 inches with higher amounts possible.  This will include Philadelphia, Baltimore, Washington DC. South of those areas 2-6 inches of snow will be possible, but snow amounts are less, because there is also going to be a mix of sleet and freezing rain.  Southern Maryland and Southern Delaware could see accumulating ice of 0.10 to 0.33 inches. There will be a sharp northern cutoff of the heavy snow, north of those closer to the Pennsylvania/Maryland border; say north of 1-70, 2-4 inches of snow is likely (This will include Pittsburgh) With 1-2 inches possible across the twin tiers of Pennsylvania and New York State.  As for New York City and Western and Southern Long Island you will be on the northern fringe, so right now y’all could see a trace to an inch. It is unclear if Southern Rhode Island and Southeast Massachusetts will see any snow out of this.

Behind the departing storm Arctic high pressure will drive in, very cold air will move into the Central and Eastern CONUS.

January 3rd, 2025

 

Daily forecast discussion…

Here’s a look at the current frontal chart, radar and satellite imagery.

We can see low pressure tracking west (retrograding) back toward the Hudson Bay. Radar is showing the lake snow continuing downwind of the Great Lakes, including that potent lake band east of Lake Ontario.  There is snow showers up over northern Maine associated with the retrograding low pressure. And we have snow showers advancing out of the Ohio Valley ahead of a weak system heading for the Middle Atlantic Coast. Today winds are down a bit from yesterday, but they’re still going to be breezy, especially across northern New England and near the Great Lakes.

If we look at the Upper Great Lakes, we can see the lake bands are southeast to south of the lakes. As the day progresses, the bands off of Erie and Ontario will do the same, bringing lake snow southeast and then south of Erie and Ontario. The bands should stay in that orientation into Saturday, before coming back north a bit. Those under the most persistent part of the band will see snowfall rates of 1-3 inches per hour, leading to additional snow totals of 6-18+ inches through Saturday night.  The Lake Erie band should weaken tonight into Saturday; but the band off of Lake Ontario will still be going strong on Sunday, The Ontario band should start to weaken Sunday night into Monday.

The weak shortwave trough coming out of the Ohio Valley will move off the Coast and then head for Atlantic Canada and the Gulf of St Lawrence over the weekend. This will bring some light snow for southern Pennsylvania, northern into central Maryland and Delaware. A trace to 3 inches will be possible.  Winds will remain breezy over the weekend.

Then we will be dealing with the system currently coming ashore on the Northwest Coast, for Sunday night and Monday. We will see low pressure develop south and east of the Rockies, then this will develop[ and deepen as it moves east. The basic setup for that storm hasn’t changed all that much from what I laid out yesterday. The models have been waffling north and south as they try to figure out where the confluence zone, I talked about will set up. Right now, it’s still looking to be suppressed south, keeping the heavier snow over the Virginias, southern Pennsylvania and Central New Jersey and points south in the Middle Atlantic.  Pittsburgh, Philadelphia, Atlantic City, Baltimore and Washington, D.C., look to see a few inches to perhaps several inches of accumulation. Across the rest of Pennsylvania and New Jersey (including Trenton) snow showers are more likely with some light accumulation possible, New York City could be on the cusp of seeing some accumulation. The snow could brush the New York State southern tier and parts of southern Connecticut and Rhode Island. Southern Maryland and Southern Delaware could be dealing with sleet and ice out of this, which would reduce snow amounts.  Any track farther north will change the snow/ice shield north with it.

Who sees what will depend on how the shortwave interacts with the dynamics and how the storm will track. as we get into the Weekend, we should get a better idea on what will happen. This storm will be out of here by Tuesday. Then we will be dealing with the very cold conditions, along with a chance for another storm next week.

 

 

January 2nd, 2025

 

Daily forecast discussion…

Well, we made it to 2025. I hope all y’all had a safe and wonderful New Years Eve and Day. I’m very thankful for those of y’all who are following my Wx4Cast blog post. I want to start up a YouTube channel about Northeast weather. While this will increase my workload, I do think it will make for a better experience for all y’all. But that is going to depend on having a lot more eyes and views on a daily basis. I want to go into the YouTube venture knowing it will be successful. So, I will need your help to make that happen.

This post will be rather long, as it will cover the weather over the next few days, as well as go into a lot of detail on the weather pattern for January into February.

For today into the Weekend…

Here is a look at the current surface chart and radar. We can see a trough moving over the region, with lingering snow showers over parts of the region, as the system departs. We have an upper-level low (circled on the satellite chart) over southeast Canada, this is drawing in the cold breezy air, leading to the lake effect snow is falling downwind of Lake Erie and Lake Ontario. Winds will be windy/breezy today. The bands should stay generally where they currently are southeast of Lake Ontario, and over places like the Boston Hills off of Lake Erie, along with chances for thundersnow. Then tonight they will shift north closer to Buffalo and onto the southern Tug Hill. They will stay here for most of Friday, before drifting back south for Friday night into Saturday. On Saturday the Erie Band should be weakening, but the Lake Ontario band will keep going into Sunday before weaking and dissipating. Off of Lake Erie those under the most persistent bands will see 1-2+ feet of snow, while the persistent bands off of Lake Ontario will see 2-3+ feet over the course of the next few days, under the heavy band, thundersnow can be expected.  With the winds, there will be blowing and drifting snow causing reduced visibility and difficult travel conditions within these bands. Then for Friday, away from the Great Lakes winds will lessen.  Over the Weekend, the upper-level low over Southeast Canada, will retrograde (move west) toward the Hudson Bay. This will become a player in the setup for Sunday and Monday.

 

On Friday a weak disturbance (red circle on satellite) will be dropping out of the Midwest, this is going to slide east-southeast heading for the Mid Atlantic Coast, this could bring some light snow showers to parts of southern Pennsylvania, Maryland, Delaware into the Delmarva. This will move offshore, and become a player in what happens for Monday into Tuesday.  Once offshore this is going to deepen and head toward Atlantic Canada. Winds will become an issue again on Saturday.

We will have a system that will be coming ashore on the West Coast tomorrow, then we will see low pressure develop over the Rockies.  This storm will then be coming east continuing to develop as it does so.  That strong area of low pressure up near the Canadian Maritimes, will force this system south. Another big factor will be warm air streaming in from the south and cold air dropping out of the north, as this will play a role in the storm track. The storm will be entering the Tennessee and Ohio Valleys by Sunday. Then for Monday into Tuesday this will be sliding east then head out to sea. This has the potential to bring an ice storm for areas south of our region. But there are some signs that this could trend north a bit, which would bring Maryland and Delaware into southern New Jersey in line for sleet and ice. If the storms stay south, it has a chance to bring the first accumulating snow of the season is likely for the Middle Atlantic region as well as the Delmarva Peninsula.  Snow could be heavy at times. Some of this could push into Southern Pennsylvania, especially the Allegheny Mountains and the Laurel Highlands. But again, if the storm trends north the heavier snow could be across Pennsylvania and northern and central New Jersey, New York City and Long Island could also cash in on heavier snow amounts. Which one of these scenarios occurs, will depend on the atmospheric dynamics and wind flow (confluence) caused by that strong storm in Newfoundland and Labrador and low pressure near the Hudson Bay.  

 

 

Looking ahead…

 

The cold air outbreak I’ve been talking about for what seems like forever, is upon us. So here is a little bit that explains why this is occurring.

The cold will be coming in three main waves. The first wave of cold is coming in now behind the New Years disturbance. A second shot will come in over the weekend with that southern system. Then a third much more substantial shot of arctic air will come in next week. The third wave will be accompanied by a piece of the polar vortex that will be dropping into North America.

This won’t be a short deration cold snap, instead it will last for two maybe three weeks, where interior parts of the Northeast will likely experience subzero temperatures for many days.  We can expect temperature departures of 30°F to perhaps 50°F degrees below average, with some areas in northern parts of the region experiencing general anomaly departures greater than that.

This is going to be a deep trough that pushes the cold air into the interior Southeast and likely into Texas, the Gulf Coast into Florida, first to second weeks of January.

Pacific equatorial sea surface temperatures (SSTs) anomalies are below average, between the Dateline and the South America coast, indicating that a weak La Nina event is trying to get its act together. But if these does indeed happen, it might be too late to have a big impact for January into February. So much of the rest of winter could be under the influence of the Madden-Julian Oscillation (MJO), Arctic Oscillation (AO) and North Atlantic Oscillation (NAO).

 

 

As I’ve said many times, the PV is just an area of low-pressure over the arctic with wind that loops around the North Pole in the upper Atmosphere. Currently the AO is near neutral. Then looking at the chart, we can see the AO will become extremely negative, when the AO is negative, the PV is considered weak and it can become stretched or have pieces break off and move south.

The NAO currently is neutral to weak negative. From here it’s going to become  strongly negative for a large part of January. When the NAO is in positive phases the eastern U.S tends to see above-normal temperatures, with the opposite being the case when the NAO is negative. We tend to see more high latitude blocking events when the NAO is in its negative phases.

The MJO currently is in phase seven. Then the MJO is looking to be at least mid-amplitude for a bit while in phases 8 and 1. When this happens, we will see ridging in the Western US and a trough develop in the East, allowing colder air to our north coming down to visit.

The Pacific North American (PNA) index. Looking at the chart, we can see this is going to be positive. This reinforces the NAO and AO ideas of increased cold here in the Eastern CONUS.  When the PNA is positive it greatly increases the NAO’s influence on temperatures here in the Northeast. A 2006 paper done by M. Notaro, W.C. Wang AND W. Gong showed that a positive PNA enhances the chances of troughing over the East Coast, with the Jet Stream suppressed south. The paper also showed a positive PNA increases the chance for lake effect events.

All of these teleconnections are showing a strong signal for a very cold pattern that favors snow storms.

I expect to see at least one big nor'easter during this time period.  

Places that have significant snow cover will help the Arctic air to spread farther southward spread, bring very cold air into the southern states. The pattern over the next couple of weeks will be less favorable for the cutters and inland runners that we have been seeing. So, if you want to see a coastal this is the pattern for you.

The teleconnections are showing the pattern breaking down once we get past mid-month. Based on the data, this would likely come about after the 19^th of January.

I'm still expecting the pattern to warm end of January, before the return of another cold shot during the first part of February, as this back and forth pattern looks to continue. 

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