March 13, 2023

Another Atmospheric River Hits California As New England Deals With A Nor'easter

Two major storms will bookend the country on Tuesday, bringing more flooding rains and prolific snows to California while New England deals with its strongest nor'easter of the season.

The Setup

A jet stream firmly parked over the southern half of the United States will set the stage for the two major systems we'll have to deal with over the next couple of days.

Out west, upper-level winds will funnel a rich plume of moisture straight into California. (Stop me if you've heard this one before.) This latest atmospheric river will fuel widespread heavy rains at lower elevations and very heavy snows for the Sierra Nevada.

Back east, the combined lift of a trough digging across Eastern Canada and that strong jet stream over the southeastern U.S. will lead to the rapid development of a low-pressure system off the Mid-Atlantic coast late Monday evening.

This low will spin itself up in a hurry, likely meeting the criteria for bombogenesis, or a "bomb cyclone" as you'll probably hear it termed. This just means that the storm's minimum pressure will deepen very quickly, leading to wicked winds and widespread heavy snowfall across much of New England.

More Flooding For California

A weather alerts map of California today looks like a toddler went at it with a fresh pack of Crayola and a vivid imagination. The state is blanketed with flood watches, wind advisories, high wind warnings, and winter storm warnings for the mountains.

Source: NWS

Wind gusts could reach 50 mph for much of the northern half of California through Wednesday, with gusts up to 70 mph possible along the coastline and elevations above 1,000 feet. Those winds could easily lead to downed trees and power outages, especially with soils soaked from all the rain over the past couple of weeks.

There's plenty more rain where that came from. The latest forecast from the Weather Prediction Center paints widespread rainfall totals of 3-5 inches along the coast, with up to 2.5 inches in the Central Valley and higher totals up north. Much of that precipitation in the mountains will fall as snow, with five feet of additional snow possible above 8,000 feet. 

This latest slug of rain and snow will add further stress to the region's waterways, many of which already spilled over their banks with the round of precipitation a few days ago.

As always, stay alert for flooding and be prepared to change your travel route if you come across a flooded road. It's impossible to tell how deep the water is until it's too late, and it only takes a few inches of moving water to lift a vehicle and carry it downstream. California's hilly terrain increases the odds that there may not even be a roadway left under the floodwaters.

Heavy Snow And High Winds For New England

Meanwhile, the East Coast will soon deal with a storm that could be its most significant thump (in fact, one of its only bouts) of wintry weather this year.

A classic nor'easter will spin up off the East Coast tonight and roar through early Wednesday morning, targeting much of New England with heavy snow and high winds for the day Tuesday.

The storm will really get cranking early on Tuesday morning, plastering almost everyone from northeastern Pennsylvania to coastal Maine with double-digit snowfall totals by the time the storm is over on Wednesday.

Most of the snow will fall north and west of I-95, sparing Philly and New York from much more than a dusting at best. Higher elevations in upstate New York could see up to two feet of snow.

Boston is going to be right on the borderline between a nuisance and a solid storm, with about 6-8 inches of snow in the forecast right now—with much lower totals just east and much higher totals just west. It wouldn't take much of a nudge in the storm's ultimate track to push that fine line in either direction. I don't admire local meteorologists up there right now.

Strong winds of 50-60 mph are likely during the storm, which will lead to tree damage and power outages for many location. This is going to be a wet, sloppy snow, to boot, which will weigh down trees and power lines and make damage and outages even more likely. Coastal flooding is also possible.

Heavy snowfall rates and high winds will lead to reduced visibility during the height of the storm, with whiteout conditions possible at times. If you have to travel through the area, it'd be a good idea to get where you need to go by Monday night and plan to stay put for a couple of days. 

[Top Image: Tropical Tidbits]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


February 25, 2023

2023's First Moderate Severe Storm Risk Targets Oklahoma With 75+ MPH Winds

This year's first big threat for severe weather will target Oklahoma this weekend as forecasters expect a dangerous squall line to sweep across much of the state on Sunday.

A robust low-pressure system will develop over the central Plains this weekend as a trough crests the Rockies. This is the same trough responsible for all that wild snow in California—that's a lot of energy heading east.

Plenty of warm, humid air bathed over the southern Plains will provide ample fuel for vigorous thunderstorms to develop along and ahead of this low-pressure system's cold front through the day Sunday.

There's enough wind shear that forecasters with the Storm Prediction Center expect a powerful line of thunderstorms to develop along the front. They've issued a moderate risk—a 4 out of 5 on the scale measuring the threat for severe weather—for a chunk of western Oklahoma, with an enhanced risk extending east to cover the rest of the state into southwestern Missouri.

This is the highest risk issued by the SPC since December, and it's especially noteworthy because it's for Day 2—they usually wait until the day of the event to upgrade to a high-end risk, a move that conveys their confidence in widespread severe storms on Sunday.

Damaging winds in excess of 75 mph are the main threat with the storms on Sunday, covering the Oklahoma City and Tulsa metro areas, as well as Joplin and Springfield in southwestern Missouri.

Widespread severe wind gusts can cause tree damage and power outages. Folks are often taken by surprise by the strength of severe squall lines, swearing that they witnessed a tornado or "inland hurricane" instead of a line of bad storms.

In addition to the risk for widespread damaging winds, we could see tornadoes develop within the squall line and in any discrete thunderstorms that bubble up ahead of it. Tornadoes embedded in squalls can happen very quickly, sometimes reducing tornado warning lead time down to a few minutes at best.

Folks on the Plains are well versed in tornado safety, but given that it's February and these tornadoes could happen quickly, it's worth taking a few minutes to prepare.

Make sure you (or anyone you know in the area) has a way to receive warnings and get to safe shelter the moment they're issued. Take a look at your phone's settings and ensure that wireless emergency alerts are turned on and activated for tornado warnings.

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


February 22, 2023

Thursday Could Be One Of The Southeast's Hottest February Days On Record

The winter that's barely wintered rolls on across the southeastern U.S. this week as a ridge over the eastern half of the country threatens all-time monthly records on Thursday.

February 23, 2023, could be the hottest February day ever recorded for multiple cities from the Gulf to the Chesapeake, with predicted high temperatures in the low 80s more common of late spring than late winter.

A highly amplified pattern over North America gave rise to a significant winter storm plaguing folks across much of the northern U.S. and Canada, with a widespread blizzard ongoing in the Upper Midwest while a major ice storm looms for folks near Toronto.

The East Coast drew the long stick on this setup—as we have for most of the season—coming in on the warm side of the equation. A big upper-level ridge will combine with blustery southerly winds feeding into that winter storm to send temperatures to levels almost unheard of in February.

Here's a peek at the National Weather Service's predicted highs for Thursday afternoon:

That's pretty darn warm! The average high in Birmingham, Alabama, doesn't reach 80°F until about May 5, and the average high doesn't climb to 80°F in Greensboro until June 1st. 

(*Note: The temperatures on my map don't line up perfectly with the National Weather Service's point forecast because of the pixel-based process I use to add temperature labels to my map.)

It's so unusually warm that we're on the cusp of breaking all-time monthly heat records across the southeastern states.

Based on current forecasts, Birmingham, Charlotte, and Charlottesville all stand to break their all-time February temperature records, with cities from Mobile to Baltimore coming awfully close to shattering their respective records.

If breaking yet another round of all-time temperature records sounds is. Many of these records have only stood for a couple of years, as late-winter warm spells in 2017, 2018, and 2019 each shattered all-time monthly records of their own. 

This follows an overall trend in heat records vastly outnumbering cold records as the climate warms. Average temperatures are on the rise across the United States, and the greatest warming trends have been observed during the winter months, according to Climate Central.

Thursday's predicted temperatures are all 20+ degrees above normal for this time of year.

[Top Image: Tropical Tidbits]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


February 20, 2023

Record Snows Possible As Major Winter Storm Aims For Northern U.S.

A high-end, highly impactful winter storm will sweep through much of the northern half of the country this week, producing deep snowfall and blizzard conditions along its path. The storm's worst will focus on southern Minnesota, where more than a foot-and-a-half of wind-driven snow is possible.

The Setup

The upper-level pattern developing over the U.S. this week will resemble a case study from a meteorology textbook.

Source: Tropical Tidbits

A vast trough over the western half of the country will give rise to the sprawling low-pressure system that'll cause all the headaches for folks up north, while a formidable ridge over the east will give some areas a run at the warmest temperatures they've ever recorded in the month of February.

My town in north-central North Carolina could hit 83°F on Thursday afternoon—the second-warmest February day since records started here in 1901. Raleigh could rocket up to 87°F, shattering their monthly all-time temperature record by a couple of degrees.

When it comes to direct impacts, though, this spate of record heat is a relative footnote to the mammoth winter storm brewing beneath this impressive setup.

The seed that'll grow into our disruptive storm is over British Columbia right now, bringing widespread gusty winds to the South Coast and more than a foot of snow to the mountain passes.

We'll see this disturbance move southeast over the Rockies on Tuesday, laying the foundation for a very large winter storm to develop on the western Plains by Tuesday night.

Source: Tropical Tidbits

A push of Pacific moisture with that initial disturbance will meet up with a surge of tropical moisture from the south (gawk at the animation above to see it in action).

This atmospheric doubletake will provide a vast reservoir for this developing storm to produce all the rain and snow it wants—and it sure seems like it'll live up to its potential.

Heavy Snow

Snow is the biggest concern with this system. Here's the Weather Prediction Center's latest forecast showing the probability of 4 or more inches of snow through Thursday evening.

Source: Weather Prediction Center

That's a significant swath of land expecting a healthy blanket of snow!

Here's the same forecast showing the probability of more than 12 inches of snow:

Source: Weather Prediction Center

Forecasters are increasingly confident that a huge chunk of the Upper Midwest stands to see more than a foot of snow through the end of the week, with parts of Minnesota and Wisconsin—including the Twin Cities—possibly seeing 18+ inches of snow from this system.

A foot-and-a-half of snow is common with a nor'easter on the East Coast, but it's a solid, high-end storm for the Upper Midwest. If that scenario played out, it would be at least the 8th largest snowstorm on record at Minneapolis-St. Paul.

Snowstorms in the middle of the country typically don't have this much moisture to work with—it's usually their winds that cause issues more than the immobilizing amounts of snow. 

Source: National Weather Service

Blizzard Conditions

This storm certainly won't be short on winds. 

Widespread gusts of 40-50 mph will create a lengthy period of blizzard condition from the Rockies through the Upper Midwest.

The combination of heavy snow and fierce winds will reduce visibility to zero for many hours during the height of the storm. People caught on highways could get stranded without aid for a life-threatening period of time. Air travel will be a headache days after the storm, with the ripple effects of delays and cancellations at major hubs affecting flights across the country.

Bitter Cold Soon To Follow

Source: National Weather Service

Adding insult to injury, a burst of extremely cold temperatures will immediately follow behind the storm as it exits to the east. Subzero daytime highs will be the norm in Montana and North Dakota. The National Weather Service predicts a low in Minneapolis of -7°F after the snow stops on Thursday night. Highs will struggle to reach the teens there on Friday.

Very cold temperatures across the northern Plains and Upper Midwest will combine with lingering breezy conditions to make for dangerous wind chills across the region. Frostbite and hypothermia will be a concern for anyone spending a while outside after the storm trying to clear the snow. 

[Top Image: Weather Prediction Center]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


February 2, 2023

Dreaded Polar Vortex Drags Intense Freeze Over New England To End The Week

The much-maligned polar vortex will live up to its reputation over the next couple of days as some of the coldest temperatures on the planet dive south over New England on Friday and Saturday.

The polar vortex is a large-scale circulation that wraps around the Arctic Circle. It's strongest in the winter months, when it acts like a moat keeping the winter's coldest air confined to the far northern latitudes.

Every once and a while, this circulation will become unstable, creating troughs and upper-level lows that break off and head south. When this happens, it drags that bitterly cold air south right along with it.

A model image showing the upper-level pattern responsible for New England's deep freeze on Friday and Saturday. (Tropical Tidbits)

A fast-moving upper-level low—once part of the polar vortex circulation—swooping over eastern Canada is responsible for this impending blast of very cold air sagging into New England.

Temperatures will dive well below zero for many areas, with wind chill values in the double-digits below zero. The wind chill in Boston will dip below -30°F on Saturday morning, with wind chill values reaching the -40s in western Massachusetts. The National Weather Service predicts wind chill values all the way into the -60s for northern parts of New Hampshire and Maine.

(NWS Caribou)

Don't underestimate the risk posed by such low temperatures. This is dangerous cold, the kind that can cause serious injury in just a couple of minutes. Frostbite can develop on unprotected skin in as fast as two minutes with temperatures and wind chill values this cold.

It's not going to last long, thankfully.

The pattern is pretty progressive, so the upper-level low responsible for the extreme cold will move along in a hurry. A ridge will build in behind it, allowing temperatures to rebound to above-normal territory in time for next week.

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


January 19, 2023

Enhanced Risk For Severe Storms Across Ohio Today, Because Of Course, It's January 19th

There's an enhanced risk for severe weather across much of Ohio today.

Of course.

Because that's just what you'd expect for the middle of January.

A low-pressure system moving across the Great Lakes region is responsible for all sorts of foul weather across the central U.S. this week. The system plastered a solid swath of snow from Denver to Duluth over the past couple of days.

Now that most of the wintry weather is north of the border in Ontario, we're left to deal with the volatile southern end of the storm today.

The core of the low will spend Thursday scooting across the Midwest in a hurry. Southerly winds feeding into the center of the low will drag warm, humid air from the south. The system's cold front will crash into this modestly unstable air, made a little more unstable by the amount of cold air aloft.

This setup will lead to a fast-moving line of severe thunderstorms developing along that cold front during the latter half of the afternoon. We'll see the squall line develop in central Indiana not long after noon, racing east into Ohio through the mid- to late-afternoon hours.

You can see a simulated radar image from the HRRR weather model at the top of this post, covering the 5:00 p.m. timeframe. 

A risk for severe weather covers about all of Ohio on Thursday afternoon, radiating out to include eastern Indiana, western Pennsylvania, and far northern Kentucky. Within that area is a bullseye of sorts, an enhanced risk—a three out of five on the categorical scale measuring the risk for severe storms—that includes Dayton and Columbus.

Damaging wind gusts are far and away what concerns the Storm Prediction Center the most with Thursday's storms. The enhanced risk is in effect for the potential for significant wind gusts of 75+ mph, which are plenty strong enough to knock down trees and power lines across the affected areas.

There's also a small—but not zero—risk for tornadoes in and around the enhanced risk. This kind of setup carries the risk of "kinks" developing along the leading edge of the squall line, which could spin up short-lived but fast-moving tornadoes.

Honestly, the most dangerous part of today's severe weather risk is the fact that it's January 19th.

Severe storms are more common in Alabama and Louisiana this time of year. Not so much in Ohio! Many folks across the affected areas won't be tuned-in to severe thunderstorm watches and warnings as these fast-moving storms approach.

If you live in the area, please let your family, friends, and neighbors know that there's a risk for rockin' storms today. If you know anyone in the area, drop a note on Facebook or Twitter or Mastodon or wherever that these storms are coming this afternoon.

Severe weather is dangerous any day, but it's even worse in the winter when most folks aren't on the lookout for watches and warnings.

The risk for severe weather will quickly diminish after sunset, and no more severe thunderstorms are in the forecast for the remainder of the week.

As it should be.

In January.

[Top Image: WSV3]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


January 4, 2023

California Flood Risk Ramps Up As Another Atmospheric River Washes Over West Coast

Widespread heavy rain, high winds, and many feet of mountain snows are on the way to California over the next couple of days as another powerful storm swirls off the coast.

This latest wash of heavy rain will lead to a heightened flood risk for much of coastal California, with many communities still cleaning up the damage from the prolific rains that fell over the weekend.

We're in the midst of an exceptionally unsettled stretch of weather across the West Coast as a series of potent low-pressure systems take aim at the region.

This week's atmospheric river will bring the risk for several inches of rain across a wide swath of coastal California. The Sierra Nevada will see very heavy snow, with areas above 5,000 feet piling up multiple feet of snow over the next few days.

Source: NWS/WPC

The Weather Prediction Center (WPC) issued a moderate risk for excessive rainfall for much of the day Wednesday. This means that there's at least a 40 percent chance of rain exceeding flash flood guidance, or rain falling fast enough to trigger flash flooding in certain areas. Moderate risks don't come around too often, so that's a strong sign that vulnerable areas will see dangerous conditions.

We'll see high winds accompany the heavy rainfall through Thursday. Much of California is plastered in high wind warnings as gusts will reach 40-60 mph in most areas. Higher elevations could see gusts up to 70 mph at times. Since the ground is soaked from recent and ongoing rains, the winds will likely lead to tree damage and power outages in spots.

It's not over once this storm moves along, either.

The WPC's latest precipitation outlook for the next seven days shows 10-15+ inches of rain falling on a huge swath of California through next week, with the heaviest precipitation focused on northern California and the mountains.

A continued train of storms will focus on California in the coming days, with about a day or two of spacing between each one. We're seeing this relentlessly wet pattern as a result of a powerful jet stream sagging pretty far down over the Pacific Ocean.

Source: Tropical Tidbits
This jet isn't moving very much, so it has the opportunity to pump out one storm after another as each trough breaks at the end of the jet like a wave crashing on the beach.

Additional strong systems could reach the coast by this weekend, early next week, and late next week.

Remain mindful of the dangers of flash flooding. It's impossible to tell how deep the water is until it's too late. It takes surprisingly little moving water to lift up a vehicle and carry it away. Most freshwater flooding deaths in the U.S. occur when people drive their vehicles into deep or moving waters. Sometimes, especially in a hilly state like California, the road may be completely washed out under the water.

If you're under a wind advisory or high wind warning, you're at risk for power outages. It'll take crews longer to restore power during bad weather.

Make sure you've got batteries and flashlights on hand so you can see in the dark without wasting your cell phone battery on the flashlight feature. Rechargeable cell phone battery packs are also a great investment—they're relatively cheap now and most can provide one or two boosts to a smartphone's charge.

[Top image created using WSV3]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.


December 31, 2022

New Year's Winter Storm Threatens Blowing Snow, Severe Storms, Significant Warmth

A developing winter storm will tick almost every box on the hazards checklist to start the first week of the new year as a low-pressure system strengthens over the center of the country.

The system is over California right now, bringing plenty of much-needed rain to lower elevations and very heavy snowfall to the mountains. This low will traverse the Rockies this weekend, eventually emerging over the Plains on Monday as a fast-developing Colorado low.

We'll see widespread winter weather across northern sections of the Rockies and the Plains through Tuesday, with several feet of snow falling at the peaks and a decent, shovelable snowfall for areas like Denver, Boulder, and Cheyenne. Freezing rain and sleet are possible closer to the track of the low.

Snow and a wintry mix will continue into the Upper Midwest as the storm peaks in strength as it pushes into the Great Lakes on Tuesday.

Southerly winds pulling into the storm will drag warm, humid air deep into Canada as the low strengthens and moves through, bringing very warm temperatures to just about everyone in the eastern half of the U.S.

The calendar may say January, but the thermometer is going to scream April. Tuesday's highs will climb into the 70s as far north as West Virginia, with 60s reaching western New York—still buried under many feet of snow from last week's blizzards.

A few inches of rain could fall through early next week with this system. The rapid warmup and arrival of heavy rain could lead to flooding in areas where the ground is frozen or there's still significant snowpack from last week's storm and lake-effect bonanza.

Farther south, the system's cold front plowing into that warm and humid airmass will trigger a round of severe thunderstorms across the Deep South on Monday.

The greatest threat appears centered on the Arklatex region, with the threat stretching out to include Little Rock and Shreveport. These areas could see the threat for "potentially significant damaging gusts and a couple of strong tornadoes," the Storm Prediction Center said on Saturday.

Colder air will move in for a couple of days behind the system, but it's not going to last too long or get too cold. In fact, winter's deepest chill seems like it wants to chill out on the northern Plains for the next couple of weeks, sparing the rest of us with milder conditions through the first half of the month. (And even there it'll be warmer than normal.)

The Climate Prediction Center's latest outlook through January 13th tells the tale—decent odds of warmer-than-normal temperatures for almost everyone. Ahh, winter.

[Top Map: NOAA/WPC]

You can follow me on Facebook, Mastodon, Twitter, Instagram, or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.