An active stretch of weather continues with a major storm developing today and tomorrow, followed by a serious blast of Arctic air across much of the country next week and the potential for an East Coast storm.
The next storm up: More flooding, more Midwest snow, more strong wind
The next storm in our parade is gathering in the Rockies today. This one will track south into the Texas Panhandle and then hook back northeast across the mid-Mississippi Valley into Michigan, Ontario and Quebec into the weekend. At its peak, this storm will likely test some January low pressure records in the Midwest, including in places that just set them earlier this week.
So, yes, it’s active.
There will be some tweaks compared to the storm earlier this week, but in general, the story is similar in some ways. Let’s run through the impacts.
Heavy rain & flooding: The Northeast and parts of the Mid-Atlantic will again be ground zero for flooding risks from this storm. Another inch and change of rain is expected here into portions of Atlantic Canada, on top of saturated ground and ongoing flooding in spots. While these totals are lower than the previous storm this week, the ground is more saturated now than it was then, so less rain can cause issues.
The Weather Prediction Center has the area outlined for the upper end of a slight risk (level 2 of 4) for excessive rainfall, close to a moderate risk.
Flood Watches are already posted in parts of southern New England.
Severe weather: Another round of severe storms is likely from northeast Texas into the Lower Mississippi Valley later today, and an enhanced (level 3/5) risk is in place for parts of Arkansas and extreme northeast Texas, and northwest Louisiana.
That will expand into the Southeast on Friday, where another enhanced risk is already established from Alabama through the Carolinas. This map may be updated after publication.
Tornadoes and damaging winds will be a possibility in these areas on Friday.
Heavy snow: The storm earlier this week brought heavy snow in a corridor from Kansas through Nebraska, northern Missouri, Iowa, northwest Illinois and southern Wisconsin into Michigan. Tomorrow’s storm will bring the heaviest snow from Nebraska into Iowa, Wisconsin, northern Illinois (including Chicago), and Michigan into Ontario.
An additional area of heavy snow will be possible in Upstate New York and interior New England, particularly in the mountains. That will extend into Canada with heavy snow across Quebec (outside of Montreal) and in Newfoundland and Labrador.
More travel headaches are expected in those areas.
Meanwhile, as that storm exits east, another storm, the one that will really help drag in the Arctic blast for early next week, will dump snow in the Western U.S.
We’ve been in a bit of a snow drought nationally this winter, so this is helping to make up some ground.
Strong winds: In addition to the heavy rain and flooding, heavy snow, and severe weather, widespread strong winds will once again tax trees and power lines across the country. A huge chunk of the nation will see 35 to 50 mph wind gusts in the coming days, with the worst coming in parts of the Rockies, Texas, Appalachia, the Great Lakes, and on the Northeast and Mid-Atlantic coasts into Atlantic Canada.
This has been a pretty remarkable week for wind across the Lower 48. I know we have a subset of readership in portions of Atlantic Canada, so I just want to note the wind gusts there as well. They may not be as strong as explicitly shown on the map below (especially east of Nova Scotia), but I just want to highlight that the wind doesn’t magically stop in Maine.
Really an impressive stretch lately.
Arctic blast next week impacts much of the country
As alluded to above, the cold coming next week looks impressive. Nationally, it may be the coldest outbreak since just before Christmas in 2022. Numerous locations are already forecast to reach record lows on Monday and Tuesday next week.
This won’t be as long lasting or potent as what was seen in February 2021 in Texas, but it marks yet another in a series of winters with some sort of cold air shenanigans in that part of the world. The core of the coldest air relative to normal will likely pass over the northern Rockies Sunday and Monday, the central Plains and Mid-Continent Monday and Tuesday, and into the Ohio Valley and Southeast on Tuesday and Wednesday.
For folks in Texas, this will be a prepare for impacts type of cold: Protect plants, pipes, pets, and people. The shorter duration of this event compared to February 2021 should hopefully take some of the more catastrophic problems off the table (like grid failure), but cold of this magnitude in this part of the world can always spring surprises on folks. So please take it seriously and prepare accordingly.
A second push of cold may arrive again next weekend, but that’s TBD at this point.
East Coast storm chances next week?
The rumor mill is cranking on the potential for an East Coast winter storm next week. As the Arctic air slides east, a secondary storm is expected to develop in the Southeast and track off the East Coast. Exactly where it tracks will determine what, if anything is seen in parts of the Southeast, Mid-Atlantic, or Northeast. We’re still a good 5 to 6 days or so away from this, so there’s plenty of uncertainty.
Let’s look quickly at the Euro ensemble “spread” in options for this storm. The IQR values for sea-level pressure shown on the map below from Tomer Burg are high, which tells us that there is considerable spread within model guidance for potential outcomes. The European ensemble runs the European model 51 different times with different tweaks each time. When you see this sort of variability within the ensemble, it lends to lower confidence in the forecast track of the storm. Obviously that will have huge implications on what sort of precip falls and where.
So it’s much too soon to say with any confidence who will see snow and how much next week. Suffice to say, however, there is a storm system likely that will cause impacts on the East Coast, continuing our active weather pattern. Milder weather may be on the horizon for later in January.
Total rainfall will be on the order of 1 to 3 inches in this region, which is plenty of water to produce flash and river flooding. Flood Watches are up from southern New England into Virginia, and tomorrow should be a very active day.
There are a ton of other elements to this storm. Let’s walk through them.
Severe weather: Tonight looks to be a very active severe weather night in the Deep South and along the Gulf Coast east of Texas. An enhanced risk is in effect for this region (level 3/5), and tornadoes are a distinct possibility. That severe risk will continue into the southeast tomorrow with an enhanced risk from north Florida into southern Georgia, and eastern South & North Carolina.
Again, strong winds and tornadoes are possible in these areas.
Wind gusts: Widespread wind gusts in excess of 40-50 mph are possible, if not likely across the Plains, Midwest, Southeast, and East tonight into tomorrow. Coastal New England, Long Island, and the Mid-Atlantic could see 60+ mph winds. This will be an exceptionally potent and widespread wind storm across the eastern half of the country, and there will likely be numerous power outages.
Snow: A major snowstorm will occur on the northwest flank on this storm, with anywhere from 6 to 12 inches or even more across northern Missouri, Iowa, northern Illinois, and southern Wisconsin.
The combination of snow and wind will produce blizzard conditions from northeast New Mexico into Kansas, with near-blizzard conditions at times northeast of there.
But wait, there’s more!
At least two more major storms are queued up in the pipeline. The next one will take a track similar to slightly farther east than the current storm. Expect more wind, more snow, more flooding rain, and more severe weather risk on Friday into Saturday.
The subsequent storm will arrive Monday or Tuesday next week, and this one may take a farther east track, meaning we’ll watch for snow chances to creep eastward. But it could also produce more flooding and more wind in the East. Additional total liquid of 2 to 4 inchers more is almost certainly going to exacerbate flooding concerns in the Mid-Atlantic and Northeast. More to come on these.
Today’s post offers a quick summary of this weekend’s Northeast storm and focuses on a significant flooding risk with Tuesday’s storm focused on New Jersey.
Weekend winter storm: A wind-whipped pop of snow in the interior Northeast
Rain, snow, and wind will move into the Northeast and Mid-Atlantic today with the much discussed weekend winter storm.
In terms of snow, look for anywhere from 6 to 12 inches in Central Pennsylvania (mainly north and west of Harrisburg) into the Poconos and northwest New Jersey. About 8 to 12 inches is expected for Central New York into the Capital Region and Hudson Valley. Higher amounts are possible in the Hudson Valley and likely in the Catskills, where as much as 18 inches may fall in spots. Most of northern Connecticut into Massachusetts, southern Vermont, and southern New Hampshire should see 6 to 12 inches. Higher amounts up to 18 inches are possible in southeast New Hampshire, extreme southern Maine, and portions of interior eastern Massachusetts.
For the major I-95 cities, Boston should see 6 to 8 inches, Providence 4 to 6 inches, New York City 1 to 2 inches or less, and Philly through DC less than an inch.
In addition to snow, ice is going to be an issue for portions of western Virginia and portions of West Virginia.
Though we don’t foresee major icing, any ice can impact travel, so the I-81 corridor probably should be avoided today.
Gusty winds will also impact the Northeast and Mid-Atlantic today, with 40 mph or stronger gusts possible on the coast.
Last but not least, a slight risk of severe storms is in place in southwest Florida from Sarasota through Naples this morning.
Next Tuesday’s storm: Focus on New Jersey flooding risks
The second storm continues to come into focus some more. We’ve got numerous issues to face with this one, particularly gusty wind over a wide swath of the Eastern U.S., heavy snow from the Central Plains into the Midwest and Great Lakes, and the potential for flooding rains in parts of the East, with northern New Jersey being of particular concern.
We will talk more about the snow and wind later today or tomorrow, but I want to focus on the flooding risk in New Jersey right now, partially because it’s of concern, but also because I’m from New Jersey. The Weather Prediction Center already has the northwest part of the state in a Moderate risk for excessive rainfall and flooding, which is their highest category 4 days out.
We talk about snow totals during winter storms a lot, but we don’t always talk about how much moisture is actually contained within the snowpack, or what we typically call the snow water equivalent. If you melted the snow, how much water would you get? Between the rain and snowfall this weekend, much of New Jersey will see an inch or a bit more of liquid equivalent. This comes on the heels of the last 30 days which has seen anywhere from 150 to 300 percent of normal precipitation in New Jersey. It’s been wet, now we’re adding more water, as well as some snow which is likely going to melt as next week’s storm hits. Basically, you have the recipe for significant river flooding in much of the northern half of the state.
How much rain are we expecting? Between now and through Tuesday’s storm, portions of New Jersey, eastern Pennsylvania and southern New York could see in excess of 4 inches of total water.
One of the problems that highlights why New Jersey is especially vulnerable is that you will be seeing 1 inch of liquid basically already sitting on the ground with another 2 to 3 inches falling from the sky between the snowmelt and rain. This is going to send a lot of water quickly into the system, and again, that’s a recipe for flooding.
So, while the talk with this upcoming Tuesday storm is likely going to focus a lot on snow and wind and broadly heavy rain and cold to follow, folks in northern New Jersey in particular need to follow this forecast closely due to the very acute flooding risk.
Another storm is possible next weekend which could further exacerbate problems. But we’ll take this one at a time.
Today’s post goes in deep on this weekend’s winter storm in the East, previews next week’s potentially major storm in the Eastern half of the U.S., and discusses what stratospheric warming and the polar vortex actually means.
This weekend’s storm: Snow chances highest north and west of I-95
Not a whole lot. I love these IQR plots from Tomer Burg’s site. In simple terms they’re showing you the uncertainty within the modeling. When it comes to storms like this, you have to use ensemble guidance. Recall, the ensembles are 30 to 50 runs of a model with some tweaks each time, so you get a more realistic spread of possibilities. Often, when you’re watching the TV news or you see a loud post on social media, they’re showing you deterministic guidance, or what we often call the operational models. That’s the whole GFS vs. Euro thing you hear about sometimes.
But back to Tomer’s plot. On Tuesday, I noted “the European ensemble shows a number of storm tracks on either side of the Benchmark with several rather close to the coast. This means uncertainty is high.” Then, as a meteorologist, I looked to see what our cold air supply looked like, and it’s meager. All this to say that it made sense to think that snow would stay mostly north and west of the I-95 corridor, with the exception of New England, where the storm track may favor more snow. That’s a lengthy introduction to say, here we are today:
Since Tuesday, uncertainty has dropped, and we’re seeing a coalescing of ensemble members at or north and west of the 40/70 Benchmark. With this type of track and a distinct lack of much cold air, the focus of snow will likely be inland for this event, with rain or a mix at the coast. With track forecast confidence comes snow forecast confidence to a point. If we look at today’s odds of 3″ or more of snow from the European ensemble, here’s what we get:
Back on Tuesday, Washington, DC had about a 40 percent chance of 3″ or more snow. Today, that is less than 10 percent. For Philly, we were around 40 to 50 percent on Tuesday, and we’re down to about 20 to 30 percent today. New York City was 50 to 60 percent on Tuesday and may be about 75 percent today. Boston and most of Southern New England were 60 to 80 percent on Tuesday and near 100 percent today. So, over the last couple days, as the models have sort of nudged things north some, the snow cutoff has nudged with it, with lower odds in Philly and DC and higher odds in New England (as you might expect with the storm closer).
Let’s ratchet things up to 6 inches. What do those odds look like?
The 6 inch probabilities are interesting, and you can begin to see where the highest uncertainty may be. From Philly south through DC, the odds of 6″ of snow are extremely low, if not close to zero. This looks like a snow to rain or mix event there. My homeland of Southern New Jersey is in the same boat. Things get much trickier though once you get into areas north and west of Philly up into New York. The “gradient” of snow percentages increases dramatically over a short distance. For example, you have about a 10 to 20 percent chance of 6″ of snow on Staten Island but about a 50 percent chance in the Bronx. Similar style gradients exist in North Jersey and near coastal New England. That’s according to the European model. In reality, with cold air lacking, I think these odds may even be a bit too high on the southern end, and I am going to assume that most of NYC will see some wet snow to a mix or rain. The NWS in New York City highlights the chance of interior snow, with a very low chance that the city sees accumulating snow.
For New England, the battle line becomes the coast, with the typical problem areas from a forecasting perspective coming to fruition this time as well. Despite the cheery view of the Euro in Boston, the actual odds are probably a bit less than shown for 6″ or more snow there, and the NWS Boston image below shows this, with about a 50 to 60 percent chance for the city.
All in all, we’re likely looking at a storm with the greatest odds of meaningful snow from portions of interior Pennsylvania through northwest New Jersey, the Catskills, Litchfield Hills, perhaps to Hartford and Worcester, southern Vermont, New Hampshire, and Maine. For the northwest suburbs of NYC and for Boston, it will be a closer call.
Don’t overlook the wind and coastal impacts with this storm either. A pretty healthy period of wind is possible from about Long Beach Island, NJ up through Long Island and coastal southern New England. This will likely cause some minor coastal flooding and possible beach erosion as well.
Next week: A major interior U.S. winter storm with big wind possible
It’s still a bit too soon to get into the finer details, but we are likely to see a much more significant storm next week across the interior U.S. Modeling has been consistently indicating the odds of a deep, strong area of low pressure tracking from Texas into the Ohio Valley and Ontario and Quebec. This storm is going to have it all: Heavy rain, severe weather, heavy snow, and powerful winds. Here’s a quick overview of what we’ll be watching.
Heavy rain: A swath of heavy rainfall is likely on the warmer, Eastern side of this storm from the Gulf Coast up through the interior Southeast, Mid-Atlantic, and possibly the Northeast. The Weather Prediction Center already has a slight risk on day 5 (Monday) for the central Gulf Coast, which is level 2 of 3 at this timeframe.
Severe weather: The Storm Prediction Center is highlighting the chance for severe weather on Monday from Texas to the Florida Panhandle and on Tuesday in Florida and Georgia.
It’s too early to speculate on details, but just know that severe weather is a possibility early next week.
Heavy snow: There is an increasing chance of heavy snow for somewhere between Kansas and Missouri into Iowa, Illinois, perhaps Indiana, Michigan, Ontario, and Quebec. Current European ensemble model odds of 6″ or more snow are relatively high in Kansas, Illinois, northwest Indiana, and Michigan into Canada.
It’s far too early to speculate on details, but it’s apparent that someone will get a good bit of snow from this storm. One of the challenges again in this storm is a lack of cold air. There will be significant cold dumping into the Western US, but the Plains and Midwest have decidedly blah cold air available at this time. A lot of time to sort this out still.
Strong winds: In my opinion, the heavy rain in the East and the strong potential winds from this storm are the most serious looking elements next week. Modeling is at least implying the risk of a wide area of 30 to 40 mph or higher winds from the southern Plains into the Southeast, Ohio Valley, East Coast, and Great Lakes. Expect this storyline to become more noteworthy in coming days as the details of this storm get sorted out.
Is the polar vortex coming?
I want to close by addressing something that’s got a lot of people spooked or excited or more aware than usual of winter weather. There has been a lot of speculation on social media about the polar vortex coming later this month. The reasoning is attributed to a sudden stratospheric warming event (SSW) that displaces the polar vortex from the Pole and dumps cold air into the mid-latitudes where most people live. It sounds pretty terrible, unless of course you love cold. So what’s the deal, really?
Every winter, the polar vortex strengthens over the North Pole. It basically houses the coldest air in the Northern Hemisphere. It’s never perfectly still, but it’s usually confined to the North Pole. Every so often, the polar vortex can be disrupted, allowing cold to leak out of the polar region and toward the mid-latitudes, where most people live.
The image above lays out, broadly how this happens. For example, this winter has been a mild one for most of the U.S. so far, and it’s not a shock that the polar vortex has been fairly strong.
One of the pathways to displace or split the polar vortex is by what we call a sudden stratospheric warming. What is that, and why does it matter? When we talk about the “polar vortex,” most meteorologists are actually referring to the stratospheric polar vortex. We’re looking about 10 miles and higher up in the atmosphere. That’s the actual polar vortex. When you think of the polar vortex, you’re likely thinking of blobs of intense cold that periodically drop into the U.S. during winter. So, they’re two fundamentally different things. Related, but different.
During some winters, there will be a disruption of the stability in the stratosphere that happens via a sudden warming event, where the strong westerly winds locking the polar vortex over the Pole can weaken or even reverse. When that happens it can release some of that cold from the polar region into the mid-latitudes, impacting the U.S. or Europe or Asia.
But that’s not a guarantee. No two SSWs are identical, and not every SSW will lead to a “release the hounds” cold air outbreak over the U.S. (or Europe or Asia). There’s a lot that we don’t completely understand about these events and what causes one to produce big cold or another to do little to nothing. But the bottom line here is that this year we are seeing a minor SSW event ongoing. This will do some work on the polar vortex, and it should allow for a relatively wavier jet stream heading into later January. That does not mean a repeat of the February 2021 or December 2022 cold events in Texas, but it could mean some pushes of stronger cold than we’ve seen so far this winter.
One hurdle right now is that snowfall across North America is running a good bit below normal.
Snow cover is below average in the West, Canada, the Midwest, and Plains. Cold air modifies and moderates as it comes south, and when it travels over less snowy ground, it can moderate faster. This can change in the coming weeks, but will it happen in the Plains? That’s TBD.
The takeaway from all this is that a SSW event does *not* guarantee strong cold air. There are complicating factors involved that can prevent strong cold from materializing. However, an SSW event does tend to weaken the polar vortex and increase the odds that colder air could emerge from the polar regions at times in a few weeks. That does not necessarily mean a repeat of February 2021 (Uri). These types of situations occur several times a decade and most do not produce historic cold air like we saw in that event. But they can produce some of the coldest air of a given winter. So our advice: Sell the hype. But don’t be surprised if the forecast later this month turns a bit colder than we’ve seen so far this winter.