We're less than 36 hours out. The time for wondering is over.
After days of model volatility and shifting storm tracks, the guidance has finally started converging. Winter Storm Warnings and Watches now blanket areas from New Mexico to Virginia. Emergency declarations are in effect across multiple states. This is happening.
Here's where we stand this morning.
The Northern Shift Is Real, But Limited
Yesterday I told you the models had gone north. Way north. The European model had shifted nearly 200 miles in 12 hours and other guidance followed.
That trend has held. The latest runs continue to show a more northern track than what we were seeing early in the week. The I-95 corridor from Washington to New York is now firmly in the significant snow zone. That wasn't on the table three days ago.
But here's what changed overnight. The downstream tropopause vortex has trended toward a faster exit than some of the earlier guidance suggested. That sounds technical, but the practical effect matters. This is now predominantly a southwest flow warm air advection event rather than the classic overrunning setup some earlier model runs were showing.
What does that mean? Two things. First, it broadens the north-south extent of the heavy snow swath. More people see snow. Second, it lowers the maximum ceiling for snow totals in any single location. Instead of training bands dropping 18 to 24 inches on one unlucky city, the heaviest rates will gradually translate northeast. Still significant. Just more spread out.
This is a good reminder about analog years. Earlier this week, some forecasters were comparing this setup to February 5, 2010 or February 16, 2003. The large-scale pattern similarities were real. But those similarities were based on what models initially showed. The evolution since then has diverged. Don't anchor too hard on historical comparisons when the actual synoptic setup keeps shifting.
The Ice Threat
I need to say this clearly. For millions of people from Texas through the Carolinas, the ice is the story. Not the snow.
The National Weather Service is using the word "crippling" in their discussions for parts of Arkansas, northern Mississippi, and western Tennessee. That's not a word they throw around casually.
Here's what's happening. A pronounced warm nose aloft between 850 and 700 millibars will override sub-freezing surface temperatures across a huge swath of the Deep South. When precipitation falls through that warm layer and then hits the frozen surface, you get freezing rain. And we're looking at a lot of precipitation falling through that warm layer.
Two distinct zones of severe icing are now becoming clear. The first runs from northwest Mississippi through southwest Tennessee and into southeast Arkansas along the I-30 and I-40 corridors. The second sits over northeast Georgia and the western Carolinas in the higher terrain where frigid air draining south along the Appalachians will keep the surface locked below freezing even as it warms aloft.
Ice accumulations of a quarter inch to three-quarters of an inch are likely across these corridors. Some localized areas could approach an inch. That's enough for widespread power outages, significant tree damage, and multi-day recovery timelines.
Over the next few days you're going to see a lot of maps showing freezing rain QPF amounts. Some of these will look absolutely terrifying, with values of one to two inches or more. Be careful with those maps.
Freezing rain QPF shows how much precipitation falls in the form of freezing rain. That is not the same as how much ice actually accumulates on surfaces. Actual ice accretion depends on surface temperatures, wind speeds, and precipitation rates. Those raw QPF maps will be overdone. A major ice storm is increasingly likely, but don't take those numbers at face value.
Snow Totals
The snow story has clarified significantly over the last 24 hours.
The Southern Plains bullseye sits over eastern Oklahoma and northern Arkansas into southern Missouri. We're looking at 12 to 18 inches across this zone with isolated higher amounts possible in the Ozarks. Snow-to-liquid ratios will be running 15:1 to 20:1 given the Arctic air mass, so even modest liquid equivalent translates to efficient accumulation.
The Ohio Valley corridor from western Kentucky through southern Indiana and along the Ohio River is in the 8 to 12 inch range. The Euro has been particularly aggressive here, showing 14 inches for parts of northwest Ohio. That may be overdone, but it shows the potential.
The Mid-Atlantic is where confidence has increased the most. Washington D.C. is now solidly in the 4 to 8 inch range with potential for higher amounts if the storm tracks slightly farther west. One forecaster has D.C. proper in the 8-inch range before a possible changeover to sleet. Baltimore and Philadelphia are in similar territory with more uncertainty. The NWS Richmond is calling for 3 to 12 inches with the caveat that higher amounts are possible depending on where the heaviest banding sets up.
The Northeast remains the biggest wildcard. Boston meteorologists are raising alerts as confidence grows that New England could be included in significant snow. Some guidance shows 6 inches or more for Boston, though track differences between models remain substantial. A shift of 50 miles in the storm track could mean the difference between 2 inches and 10 inches for cities along the I-95 corridor north of Philadelphia.
The Hurricane Hunters flew reconnaissance into the developing system yesterday evening. That data is now being incorporated into models and should help resolve some of the remaining track uncertainty over the next couple of runs.
The Cold
This storm is not occurring in isolation. The polar vortex has displaced southward in a significant way, and an expansive Arctic high will dominate north of the storm track throughout the period.
Wind chills of 40 to 50 below zero are expected across parts of the Northern Plains Friday and Saturday. That's life-threatening cold with frostbite possible in under 10 minutes of exposed skin.
But here's what really matters. This cold isn't going anywhere. The Arctic air will bleed southward and eastward behind the storm, keeping temperatures 20 to 30 degrees below average through early next week. Monday morning temperatures across the eastern half of the country will be brutal. Single digits from Texas into the Carolinas. Below zero across the Ohio Valley. Teens and 20s in the Mid-Atlantic.
Whatever falls is going to stay on the ground for days. And for anyone who loses power in the icing zone, that's a dangerous situation. You cannot ride out multi-day power outages in a house with no heat when it's 15 degrees outside.
One model run shows another Arctic blast arriving January 29-31 and an even bigger one February 2-4. We're not warming up for at least two weeks across the Eastern U.S. Whatever preparations you make now, plan for an extended period of cold.
Timeline
Friday, January 23: Snow develops across the Texas Panhandle and western Oklahoma by late morning. Precipitation spreads into Arkansas by evening. Freezing rain and sleet begin across central Texas and the Lower Mississippi Valley. Arctic air surges into the Northern Plains with dangerous wind chills.
Saturday, January 24: This is the most dangerous day for travel. Heavy snow continues across Oklahoma and Arkansas while spreading into Tennessee, Kentucky, and southern Indiana. Significant icing occurs from northern Texas through the Mid-South. Do not be on the roads.
Sunday, January 25: System reaches the Mid-Atlantic and Northeast. Heavy snow develops from Virginia into Maryland, Pennsylvania, and potentially into New York and New England. Icing threat continues across portions of the Carolinas. This is when the 2,000-mile precipitation shield hits peak coverage with around 160 million people experiencing wintry precipitation simultaneously.
Monday, January 26 and beyond: Primary precipitation exits the coast. Arctic air remains locked in place. Some ensemble members show potential secondary development off the coast that could wrap winter impacts back into New England, but that remains lower confidence for now.
What You Should Do
If you're in the icing zone from central Texas through the Carolinas, plan for going days without power. That's not alarmism. That's what happens when a quarter inch to half inch of ice accumulates on power lines during an event like this.
If you're in the heavy snow zone, expect school cancellations extending into next week. Many districts that close Friday for the incoming storm won't reopen until Wednesday or Thursday given the extended cold keeping snow and ice on roads.
Do not plan a road trip this weekend. I've said this multiple times now but I need to say it again. This could absolutely be a situation where people get stuck on highways. Major interstates including I-10, I-20, I-30, I-35, I-40, I-44, I-49, and I-55 will see hazardous to impassable conditions at various points this weekend.
Finalize your preparations today. Check on elderly neighbors. Charge your devices. Stock up on essentials. Have a plan for staying warm if the power goes out that does not involve running a generator indoors or using your gas stove for heat.
Bottom Line
This is a high-confidence event for significant winter impacts across a large portion of the Southern and Eastern United States. The overall message from three days ago hasn't changed. If anything, it's only gotten stronger as the data has locked in.
Multiple state governors have declared emergencies. FEMA has prepositioned resources. Airlines are waiving rebooking fees across the affected region. The National Weather Service is using words like "crippling" and "potentially historic" in their discussions.
Take this seriously.
This is the one we've been watching. It's here. Be ready.
