...COLD WEATHER ADVISORY NOW IN EFFECT UNTIL 10 AM EST THURSDAY...
* WHAT...Very cold wind chills as low as 8 below.
* WHERE...Portions of central, northern, and southern Delaware, northeast Maryland, central and southern New Jersey, and southeast Pennsylvania.
* WHEN...Until 10 AM EST Thursday.
* IMPACTS...The cold wind chills as low as 10 below zero could result in hypothermia if precautions are not taken. Frostbite and hypothermia will occur if unprotected skin is exposed to these temperatures.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.
Keep pets indoors as much as possible.
Make frequent checks on older family, friends, and neighbors. Ensure portable heaters are used correctly. Do not use generators or grills inside.
A prolonged stretch of below normal temperatures is expected to grip the Delmarva region beginning Sunday and lasting through the middle of next week, with the most dangerous cold arriving Monday night into Tuesday.
A deep upper level trough will settle over the eastern United States, allowing an arctic air mass to surge southward into the Mid Atlantic. At the surface, strong high pressure will dominate the region, keeping conditions dry but doing little to prevent temperatures from falling sharply.
Cold air will steadily build into the region starting Sunday, with daytime temperatures remaining well below average through at least Wednesday. The core of the arctic air mass is expected to be centered over Delmarva Monday night through Tuesday night, when the cold will be at its most intense.
During this time, overnight wind chill values are expected to fall into the single digits and potentially below zero, especially during the overnight and early morning hours. Current indications suggest Monday night will be the coldest period, with slightly less extreme conditions expected Tuesday night.
Daytime temperatures on Tuesday are also trending colder, with highs forecast to struggle into the upper teens to low 20s across much of Delmarva. These values are well below normal for mid January and could pose risks to anyone spending extended time outdoors.
Given the severity of the cold, cold weather advisories or warnings may be issued for one or both nights. Residents are encouraged to prepare now by limiting outdoor exposure, protecting pets, and ensuring vulnerable pipes and plumbing are properly insulated.
Temperatures are expected to gradually moderate later in the week as the upper level trough begins to lift, allowing readings to trend closer to seasonal averages by Thursday.
With days as of this past week constantly being int he 50’s and even 60’s, many wonder where did winter go? Normally in the winter months across the lower 48 go through a longer duration warming trend as a recharge of the overall pattern and sign are pointing at a return to more winter weather moving back across the eastern half of the US.
Weather models are all onboard for a bigger shift in the overall weather pattern across the Northern Hemisphere Mainly what’s going on across the Pacific Ocean which is the biggest driver to the Lower 48 weather pattern for supplying the cold air and the active storm track. One thing that is peaking my interests is a significant drop in the Eastern Pacific Oscillation during the time period of the 14th-20th.
A very large negative Eastern Pacific Oscillation, or EPO, is a significant large scale weather pattern that can strongly influence temperature and storm tracks across the United States, especially during the fall and winter months.
When the EPO is strongly negative, a powerful ridge of high pressure builds over the eastern Pacific, often near Alaska and the Gulf of Alaska. This ridge acts as a blocking feature, forcing the jet stream to buckle sharply northward into Alaska and then dive southward downstream into western and central North America. As a result, Arctic air is displaced south out of Canada and into the United States.
For the western United States, a negative EPO often brings colder than normal temperatures, particularly to the Pacific Northwest and northern Rockies. The ridge offshore can suppress precipitation along parts of the West Coast, leading to drier conditions in California, while the colder air aloft supports snow in the higher elevations of the Northwest and Intermountain West when storms are able to undercut the ridge.
Across the central and eastern United States, the downstream response to a negative EPO is often a broad trough, which allows cold air to spill southward. This can lead to below normal temperatures across the Plains, Midwest, and East Coast. When moisture is available, this pattern can be favorable for winter storms, as cold air at the surface can interact with southern stream systems or coastal lows.
The strength of the negative EPO matters. A weak negative phase may only produce brief or modest cold shots, while a strongly negative EPO can support prolonged cold outbreaks, sometimes reaching deep into the southern United States. This setup can also increase the likelihood of sharp temperature swings if the blocking ridge eventually breaks down.
Weather across the Eastern US might get very interesting going forward into the mid-month.
As we head into mid-February, significant changes are brewing in the upper atmosphere that could have major implications for winter weather across the United States. The stratospheric polar vortex, a large-scale circulation of frigid air in the upper levels of the atmosphere, is undergoing a split, with one lobe shifting over North America and the other over Eastern Russia. This development could mean that winter is far from over for the Lower 48, with renewed bursts of Arctic air and even the potential for more snow.
What is the Polar Vortex?
The polar vortex is a vast region of cold, low-pressure air that resides in the stratosphere above the Arctic. It is typically strongest in winter and is contained by the polar jet stream, which acts as a barrier, keeping the frigid air locked in place. However, disturbances in the atmosphere, such as sudden stratospheric warming (SSW) events, can weaken or even split the polar vortex, allowing cold Arctic air to spill southward into mid-latitude regions, including the United States, Europe, and Asia.
The Implications of a Polar Vortex Split
When the polar vortex splits, the disrupted circulation can send lobes of cold air into different parts of the world. In this case, one portion of the vortex is expected to shift over North America, while the other moves over Eastern Russia. This could lead to:
Bitter Cold Spells: A more active intrusion of Arctic air into the U.S., potentially bringing below-average temperatures to much of the country, including regions that have recently experienced milder conditions.
Increased Snowfall: With cold air in place, any developing storm systems could tap into this frigid air mass and produce widespread snowfall across parts of the Midwest, Northeast, and even the South.
Disruptive Weather Patterns: A disrupted polar vortex can lead to more extreme weather events, including stronger storms, ice events, and even severe weather outbreaks as cold air clashes with milder air masses to the south.
What to Expect Mid-Month
As we approach mid-February, long-range models suggest a greater likelihood of colder air descending into the central and eastern U.S., potentially bringing another round of winter weather. The exact details remain uncertain, but if history is any guide, a significant polar vortex split often leads to prolonged cold outbreaks lasting several weeks.
For those who thought winter was winding down, this development is a strong reminder that the season isn’t over just yet. Stay tuned for further updates as meteorologists track the evolving polar vortex split and its potential impacts on the weather in the coming weeks.
A few changes going into this winter season with the replacement of Wind Chill products. Introducing Extreme Cold Weather products with “Cold Weather Advisories” now in place for areas of the Delmarva region starting tonight through Wednesday morning.
...COLD WEATHER ADVISORY NOW IN EFFECT FROM 6 PM THIS EVENING TO
NOON EST WEDNESDAY...
* WHAT...Very cold wind chills as low as 7 below expected.
* WHERE...Delaware, northeast Maryland, central to southern New
Jersey, and southeast Pennsylvania.
* WHEN...From 6 PM this evening to noon EST Wednesday.
* IMPACTS...The cold wind chills could result in hypothermia if
precautions are not taken. Frostbite and hypothermia will occur if
unprotected skin is exposed to these temperatures.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Use caution while traveling outside. Wear appropriate clothing, a
hat, and gloves.
Keep pets indoors as much as possible.
Make frequent checks on older family, friends, and neighbors. Ensure
portable heaters are used correctly. Do not use generators or grills
inside.
Extreme Cold Warning vs Watch and Cold Weather Advisory
Extreme Cold Warning: Take Action! An Extreme Cold Warning is issued when dangerously cold air temperatures or wind chill values are expected or occurring. If you are in an area with an Extreme Cold Warning, avoid going outside. If you have to go outside, dress in layers, cover exposed skin, and make sure at least one other person knows your whereabouts. Update them when you arrive safely at your destination.
Extreme Cold Watch: Be Prepared. An Extreme Cold Watch is issued when dangerously cold air temperatures or wind chill values are possible. As with a Warning, adjust your plans to avoid being outside during the coldest parts of the day. Make sure your car has at least half a tank of gas, and update your winter survival kit.
Cold Weather Advisory: Be Aware. A Cold Weather Advisory is issued when seasonably cold air temperatures or wind chill values, but not extremely cold values, are expected or occurring. Be sure you and your loved ones dress appropriately and cover exposed skin when venturing outdoors.
Dangerous wind chills dropping down below zero are expected for the next few nights here on Delmarva as winds will be gusting 20-30 mph. Temperatures dropping down to the single digits making it the coldest nights we have seen in the last several years.
Extremely cold air comes every winter into at least part of the country and affects millions of people across the United States. The arctic air can be dangerous. Combined with brisk winds, dangerously cold wind chill values can result. People exposed to extreme cold are susceptible to frostbite and can succumb to hypothermia in a matter of minutes. Areas most prone to frostbite are uncovered skin and the extremities, such as hands and feet. Hypothermia occurs when the body loses heat faster than it can produce it.
Prepare for Cold Weather
The way to avoid frostbite and hypothermia is to plan for extreme cold before it arrives. Don’t get caught unprepared.
Check the Forecast at weather.gov or your favorite weather app, station, etc.: Make checking the forecast part of your regular routine so you’ll know when to expect cold weather.
Adjust Your Schedule: If possible, avoid being outside during the coldest part of the day, typically the early morning. Try to find a warm spot for your children while waiting for the school bus outside.
Protect Your Pets, Livestock and other Property: If you have pets or farm animals, make sure they are not overly exposed to extreme cold and have plenty of food and water that has not frozen.Take precautions to ensure your water pipes do not freeze. Know the temperature thresholds of your plants and crops.
Fill up the tank: Make sure your car or vehicle has at least a half a tank of gas during extreme cold so that you can stay warm if you become stranded.
Update Your Winter Car Survival Kit: Make sure your car survival kit has the following:
Jumper cables: flares or reflective triangle are great extras
Flashlights: Replace the batteries before the winter season starts and pack extras
First Aid Kit: Carry essential medications with you in a purse or bag
Baby gear: Diapers and any special formula or food
Medical supplies: Materials for any special medical needs.
Food: Non-perishable food such as canned food and a can opener, dry cereal and protein rich foods like nuts and energy bars
Water: At least 1 gallon of water per person a day for at least 3 days
Basic toolkit: Pliers, wrench, screwdriver
Pet supplies: Food and water
Radio: Battery or hand cranked
Cat litter or sand: For better tire traction
Shovel: To dig out snow
Ice scraper: Have one in the car even if you usually park in a garage
Clothes: Dress for the weather in warm clothes, gloves, hat, sturdy boots, jacket and an extra change cold weather of clothes
Warmers: For body, hands and feet
Blanketsor sleeping bags: If you get stranded you’ll be glad to have it.
Charged Cell Phone: And keep a spare charger in your car
Essential Tasks After it Warms Up
Check Your Pipes: Your pipes may be frozen. Water pipes on exterior walls and in places that are subject to cold, like in the basement, attic, and under kitchen cabinets, freeze most often. Water expands as it freezes, causing pipes to burst. If they are frozen, first turn on the faucet. Water will drip as you warm the pipes. Heat the pipes using a space heater, heating pad, electric hair dryer, or hot water on a cloth. Never use an open flame. Continue until water pressure returns to normal or call a plumber if you have more issues.
Salt Your Walkways: Once it warms up enough to go out, it’s important to shovel the snow from your sidewalks and driveway or sprinkle salt if there is ice. If there is a thick layer of snow on the ground that you cannot move, salt the area so that the snow melts. You should also put down salt if there is ice on the stairs leading into your house – less than a quarter inch of ice can be dangerous!
Call Your Neighbors: Check to see that your neighbors are okay, particularly seniors, disabled persons, or others living alone. Carbon monoxide poisoning is one of the leading causes of death after extreme cold, particularly if there are power outages. Cases of frostbite and hypothermia are also common for elderly people who were stuck in their homes.
Refill Your Supplies: This cold event may be over, but there might be another one soon. It is important to always be prepared.
As winter approaches, significant changes are coming to how extreme cold is communicated to the public. Starting this season, the National Weather Service (NWS) will replace wind chill watches, warnings, and advisories with extreme cold watches, warnings, and advisories. This shift aims to enhance understanding of cold weather hazards and ensure that the dangers of low temperatures are effectively conveyed.
What’s Changing?
Previously, wind chill alerts were issued only when wind speeds exceeded 10 mph, focusing solely on the combined effect of wind and low temperatures. However, under the new system, alerts will be based on the apparent temperature, which is the lower value of air temperature or wind chill. This adjustment acknowledges that dangerous cold can occur even in calm conditions.
For example, if the air temperature drops to life-threatening levels but winds remain light, the new extreme cold warning would still be issued—something the prior system didn’t account for.
Why the Change?
The updated system reflects a growing understanding of how cold weather impacts people and communities. By removing the 10 mph wind threshold, the change aims to streamline cold weather alerts and emphasize that frigid temperatures can be dangerous with or without wind.
Wind chill, however, is not disappearing—it will still be forecasted and reported as a key factor in winter weather conditions. The new terminology is designed to simplify messaging for the public while accounting for broader climatological and health impacts.
New Guidelines for Alerts
The thresholds for issuing extreme cold watches, warnings, and advisories have been refined to align with historical climate patterns and their potential impacts. These changes also incorporate insights from recent winters, where dangerously low temperatures have posed threats even in the absence of strong winds.
Cold Weather Advisory: Issued for conditions that could cause discomfort or mild health impacts for vulnerable populations.
Extreme Cold Watch: Used to signal the potential for dangerous cold weather conditions within a few days.
Extreme Cold Warning: Issued when life-threatening cold is imminent or occurring.
A Clearer Message for Safety
By simplifying the criteria and expanding the scope of dangerous cold conditions, the new system seeks to reduce confusion and encourage timely action during winter weather events. Whether it’s protecting yourself from frostbite and hypothermia or ensuring pets and pipes are safe, these changes emphasize preparedness for all cold weather scenarios.
