It’s going to be a little chilly in the northeast this weekend. I live in Montana and deal with these kinds of temps, and windchills regularly. Just gonna do a knowledge dump here so you work through all this as fast as possible. Not going to prescribe many products, since it’s probably too late to order anything.
House
Open any cabinets or closets that have pipes in them so heat can get inside.
Disconnect and drain any garden hoses.
If you have the right setup, shut off valves to outside faucets (or those in a non-heated garage), then open those faucets to let them drain. Leave open.
Drip your interior faucets.
Locate (and label!) the main water shutoff valve to your house. If pipes freeze, close this valve immediately, and open all faucets. That should avoid cracked pipes. If you need to leave a property unsupervised through extreme cold, do this before it gets that cold.
Towels, blankets, pool noodles and similar can be used to eliminate drafts. You can even combine those!
Keep drapes closed at night for an extra layer of insulation. Open southern-facing blinds and drapes if the sun’s out to bring solar radiation inside your home.
There’s likely no need to crank your thermostat up. Doing so en masse will stress the power grid, and make it unbearable to wear base layers and other warm clothing indoors. Just make sure all parts of your home are getting airflow.
Car
Connect battery to a trickle charger, or remove and store in a warm place (safety note: batteries can leak dangerous gasses. I wouldn’t worry too much about one or two nights inside, but don’t keep a car battery under your pillow longterm and don’t keep them near any open flames).
Check your tire pressures before driving. Cold temperatures will deflate them.
Your fuel economy is going to suck. Same thing for range if you’ve got an EV. Prepare accordingly.
If you don’t have winter tires, avoid driving. All seasons begin to lose grip even on dry pavement at about 45 degrees (yes, above zero) Fahrenheit.
If you must drive, keep a full winter survival kit onboard complete with clothes and blankets etc.
Improvised methods of getting a stuck vehicle unstuck do not work, and can be dangerous. If you aren’t prepared with Maxtrax, a winch, recovery rope, shackles and whatnot, make friends with a 4x4 enthusiast. We love chances to use our toys.
Clothing
Dress in multiple thin layers, not fewer heavy layers. This will give you more control over your body temperature and help move sweat away from your body.
No exposed skin.
Sweat is the enemy. Getting wet can kill you when it’s sub zero.
Cover your eyes with ski goggles.
Wear a face mask, neck tube, or something like that over your nose and mouth.
Wear a warm hat that covers your ears. Over that, pull your hood up.
Get insulation from your boots, not your socks. Your body weight will compress your socks, even if you wear multiple pairs, reducing their ability to retain warmth. Look around for insulated boots.
Stuff hand warmers inside your gloves, on the back of your hands. This will help keep warm blood flowing to your fingers.
If your core gets cold, your body will reduce blood flow to your extremities. Often, this is why your fingers or toes get cold even if you’re wearing good gloves or boots.
Conductive heat loss is a thing. Avoid using shovels or other tools with metal handles. Avoid standing on metal surfaces.
How to Layer for extreme cold, from skin to shell
Upper body
thin base layers (anything other than cotton)
Wool or fleece mid-layer. The more breathable the better. Two if necessary
Puffy jacket
Windproof, but breathable shell
If your base layers and mid-layers don’t cover your neck well enough, wear a scarf, buff, or similar
Legs
Thin base layers (anything but cotton)
Synthetic fleece sweat pants or thick base layers (over your thin ones)
Windproof (but breathable) shell
Head
Thin ski mask, buff, or balaclava
Insulated hat with ear covers
Hood from puffy jacket and shell
Hands
thin liner glvoes
hand warmers
insulated gloves or mittens
Feet
Silk sock liners
medium weight wool socks
toe warmers
insulated boots
Dogs
Keep on leash at all times
Trim excess paw fur
Rub vaseline or Musher’s Secret into paws before going outside
If your dog tolerates boots, they help.
Purpose built dog jackets or sweaters if you have them. Kid-size garments may work on some dogs.
Limit time outside to short bathroom breaks only.
If you find a stray animal suffering from hypothermia, don't warm it up suddenly, as in a hot bath. Place it in a warm area of your home, and allow it time to recover. Provide with room temperature water and, and only give appropriate food in small amounts spaced over time.
Emergencies
Expect to be self sufficient, emergency services will be busy
Take the time to identify and mitigate potential fire hazards around your home
Make sure your fire extinguishers are handy, in both your home and vehicle
If you must travel, do so with extreme caution. Not only is there more danger than usual, but help will be harder to find.
Check on your neighbors.
If you lose power
Do not bring any combustible heat sources inside.
Move most switches to the off position, to avoid blowing circuit breakers when power returns.
If you must use a gasoline-powered generator, locate it well away from your home, and ensure the exhaust gases flow somewhere other than into your bedroom windows.
Gather your family into one area of the house that you can easily close doors around, sleep and hangout there.
Close your main water valve and open your faucets
Coolers are just insulated boxes. Keep drinking and anything else you don't want to freeze inside them. If you want to keep frozen food outside, a cooler can also keep critters out of it.
The time to check and see if your chimney is clear of dead squirrels, birds nests, and other fire hazards is before winter.
Wearing warm clothes and stacking blankets is way more comfortable than dying from carbon monoxide poisoning or in a house fire.
Portable batteries (I’m thinking of Goal Zero, Jackery, and similar) won’t charge and may not discharge in extreme cold. If they’re already warm, you can also put them inside a cooler, and run the cords out the drain hole.
Got more tips? Share them in the comments.
If you have a lengthy (time or distance) commute, you may want to pack a winter-stranded bag to keep at work. I keep toiletries, clothes (2/3 days worth) and some medium-weight cold weather gear in the bag. I also keep heavy-rated cold weather gear (thermal layers, insulated boost, heavy coats/bibs) in the vehicle that I take to work, switching that load-out between vehicles as necessary.
This is a great guide. A few things I can add from living in MN:
Vehicles:
• brush the snow off your vehicles ASAP while it's still dry. Resist the temptation to do it all later, as it my freeze into blocks of ice that are much harder to remove and increase the risk of damaging your vehicle during removal. Just pop outside and brush the snow off every few hours and thank yourself later. Also, clear ALL your windows. Don't be that person driving around like a tank commander. FYI, a snow brush WILL scratch paint and scraping ice off of your headlights and blinkers will scratch the plastic. Use a microfiber towel to push snow off of paint (again, sooner the better), and use de-icing fluid on mirrors, headlights, blinkers, etc.
• top off your washer fluid with de-icer fluid that can handle the low temperatures. Your washer jets are a critical safety tool when driving in winter weather. Keep them clear and working. De-ice them and confirm that they work before setting off.
• before it snows, stand your wipers up so they don't freeze to your windshield. Even if they don't freeze to the windshield directly ice can freeze into the wiper blades themselves and they won't work when you need them too. They'll sweep across the windshield and wipe away nothing because they're not able to flex and follow the contour of the windshield. Pro move: upgrade your wipers to bar-type wipers that don't have all the little articulating joints to freeze up. $5 says your wipers are due for replacement anyway.
• while you're at the auto parts store getting real wiper fluid and wipers, get yourself a few cans or spray bottles of Penske de-icing fluid. Use this to clean the ice off your mirrors, wiper blades, headlights, tail lights, window seals (to help keep your windows from freezing shut), and for light ice you can clear the windows with it. The most critical use is de-icing washer jets, wiper blades and mirrors.
• +1000% to Wes's recommendation for actual snow tires. Game changer and table stakes to safe winter driving. There are even performance snow tires that allow you to have a lot of fun in winter.
Warming up your car:
• an engine doing work will warm up faster than an engine just idling, so get going rather than letting your car idle in the driveway. Let it warm up at idle while you clear the last of the snow / ice off the windows, but then get going.
• use lower gears at first to keep the engine RPM a bit higher until the engine warms up. You don't need to red-line it, just try to keep it at or above 2,500 RPM (assuming gas not diesel) until your temperature gauge comes up to its normal spot, then put it back in D or shift up and drive normally. Do not rev the engine high or push it hard before it's up to temperature, just leave it a gear or two lower than usual and aim for 2,500-3,000 rpm until you get warmed up.
• leave the heat in your car turned OFF at first. It's counter-intuitive, but if you leave the heat off for the first few minutes that will let heat build up in the engine more quickly and then you can turn the heat on and warm up the cabin. In my experience this is the fastest procedure for a warm car because the engine can't give you heat it doesn't have yet. In my E46, for example, if it's cold enough and I run the heat at full blast I can actually watch my temperature gauge go down and fall below full operating temperature and all my vents will start to blast cool air. So if I start with the heat on and I'm on the highway, it never actually warms up. Remember that you're borrowing heat from the engine.
Keeping your windshield and windows from fogging up:
• your first order of business is not getting the cabin warm, it's getting the glass warm. Warm glass won't fog and warm glass won't accumulate ice on the outside as you drive. Fog freezing on the inside of your windows is especially bad for visibility.
• go back and forth between recirculating the air inside the cabin and blowing heated fresh air onto your windshield and windows. On recirculate the cabin will heat up faster, but fog will soon form on the windows. When fog starts to form, leave the heat on but switch off recirculate and direct air onto the glass so that drier air from outside can help clear the fog. Once the fog clears, switch back to warming the cabin. Rinse and repeat until the interior temperature is high enough to both feel warm AND keep the windows warm enough not to fog or freeze over.
Driving on snowy roads:
• Do the basics: increase your follow distance, slow down, think ahead, drive defensively, don't drive alongside people or in their blind spots
• Use your transmission for maximum grip, especially while braking. Even automatic transmissions will usually let you force lower gears. Gear down as you slow down so that you can maximize engine braking over regular braking. This will help you stay in the grip, especially if you catch yourself starting to slide.
Stopping on snow / ice:
• Again, snow tires!
• Stay out of your ABS as much as possible. Modulated braking pressure will stop you much shorter than just slamming on the brakes and letting the ABS figure it out. I'm talking 2-3 car lengths of difference even at slow speeds. If you feel the ABS start to stutter, decrease your braking pressure just a smidge until you stop locking up and then keep feeling for that limit as you maximize your stopping force. Practice this in a parking lot and get good at it.
• At slow speeds, if you find yourself needing to stop but you start sliding, dump the car into the lowest gear you can and modulate your brake pressure to stay out of ABS. On an auto, slam it into L like you're Vin Diesel in your favorite Fast & Furious movie. On a manual car, stick it in first or second and just dump the clutch. Trust me, it won't even stall until you completely stop. As you dump shift, you'll sometimes have half an instant of wheel slip as the RPMs resolve, but on the other side of that small slip is maximum engine braking and maximum stopping grip. You slam it into low, keep on the brakes and off the throttle and the car just sort of figures it out and gives you every last scrap of straight line stopping grip available. I've saved myself from sliding through multiple down hill red lights this way.