Winter Weather Advisories, Watches and Warnings Explained for Montana Property Owners

What is the difference between a watch, a warning and an advisory?

They are three levels of certainty and severity. A watch means conditions are favorable for a significant event but timing, location or occurrence is still uncertain. A warning means a significant, hazardous event is expected or occurring. An advisory means the weather will cause problems but is not expected to reach warning level. The NWS safety pages frame them as Be Prepared (watches), Take Action (warnings) and Be Aware (advisories).

The NWS office in Amarillo gives typical lead times: a Winter Storm Watch is typically issued 24 to 48 hours before a storm starts, and a Winter Storm Warning typically 12 to 36 hours before. Lead times vary with the event, so treat those as a rough guide.

What does a Winter Storm Watch mean?

The NWS Amarillo office defines a Winter Storm Watch as issued when heavy snow, damaging ice accumulations or blizzard conditions are possible. The national safety page describes it as conditions favorable for a significant winter storm event. It is the early signal, before the details are certain.

For a property, a watch is the time to get ready rather than react. Check that your snow service knows you are on the route, move vehicles and trailers out of the clearing path, put ice melt or traction by the doors, charge phones and flashlights, and bring in or tie down anything the wind could move. If you have trees with known weak limbs over the drive or the house, a watch is a reasonable moment to call about them.

What does a Winter Storm Warning mean?

The NWS defines a Winter Storm Warning as a significant winter weather event including snow, ice, sleet or blowing snow, or a combination of these hazards. Amarillo's version describes it as issued when hazardous winter precipitation is imminent or occurring. The alert text itself lists the expected amounts and timing for your zone, and the NWS Missoula forecast discussion usually explains the reasoning.

During a warning, limit travel and expect repeat clearing. Snow services work storms in cycles, and a long or windy event needs multiple passes. Ready.gov's advice for winter storms is to stay off roads if at all possible and, if trapped in a car, stay inside. If a tree comes down on a structure, a line or the only way out, call 911 first if anyone is hurt or a line is involved, then call for emergency tree and storm response.

What is a Winter Weather Advisory?

Amarillo's definition is the clearest: a Winter Weather Advisory is issued for accumulations of snow, freezing rain, freezing drizzle or sleet that will create inconveniences, below Winter Storm or Ice Storm Warning criteria. The national page says conditions should not be hazardous enough to meet warning criteria.

Do not dismiss an advisory. Advisories can cover light freezing rain or drizzle, and a thin glaze on a walk is a fall waiting to happen. When an advisory mentions any freezing precipitation, treat steps, ramps and entrances before it starts. Our guide to black ice on driveways and walks covers what to do.

What are Blizzard and Ice Storm Warnings?

They are warnings for specific hazards. The NWS issues a Blizzard Warning for frequent gusts greater than or equal to 35 mph accompanied by falling and/or blowing snow, reducing visibility to less than a quarter mile for three hours or more. Note that a blizzard is about wind and visibility, not snowfall amount. An Ice Storm Warning is for ice accumulation of around a quarter inch or more, which Amarillo describes as damaging ice accumulations expected within the next 12 to 36 hours.

Ice storms are hard on trees and power lines, because ice adds weight to every branch. Stay clear of any downed line and treat it as energized. Blowing snow events drift drives shut repeatedly; see drifting snow on rural driveways.

What happened to Wind Chill Warnings?

They were renamed. NWS announced that, effective October 1, 2024, Wind Chill Watches became Extreme Cold Watches, Wind Chill Warnings became Extreme Cold Warnings and Wind Chill Advisories became Cold Weather Advisories. Hard Freeze Watches and Warnings were folded into Freeze Watches and Warnings. The NWS said the changes seek to clarify that cold can be dangerous with or without wind.

The current definitions: an Extreme Cold Warning is issued when extremely dangerous cold conditions or wind chill values are expected or occurring, an Extreme Cold Watch when they are possible but occurrence, location or timing is uncertain, and a Cold Weather Advisory for dangerously cold conditions not expected to reach warning criteria. Some older pages, including parts of the NWS site, still list the wind chill names, so you may see both.

What should I do when an Extreme Cold Warning is issued?

Protect people first, then pipes. Ready.gov lists the signs of frostbite (numbness, white or grayish-yellow skin, firm or waxy skin) and hypothermia (shivering, exhaustion, confusion, fumbling hands, memory loss, slurred speech or drowsiness) and says a body temperature below 95 degrees is an emergency. Limit time outside and dress in layers.

For the house, the American Red Cross recommends letting cold water drip from faucets served by exposed pipes, opening kitchen and bathroom cabinet doors so warm air reaches plumbing, keeping garage doors closed if there are water lines in the garage, and keeping the thermostat at the same setting day and night. Outdoor hose bibs, sprinkler lines and backflow assemblies should already be drained; if not, see frozen backflow preventers and irrigation damage.

What do Freeze Warnings and Frost Advisories mean for a yard?

These are mostly fall and spring alerts. The NWS says a Freeze Warning is issued when temperatures are forecast to go below 32 degrees for a long period, noting that 32 kills some crops and plants and that below 28 for an extended period can kill most of them. A Freeze Watch is issued in autumn until the end of the growing season and in spring at its start, and a Frost Advisory means frost is expected and threatens sensitive vegetation.

The first Freeze Warning of the fall is the signal to finish the irrigation blowout and shut off hose bibs if you have not already. Our sprinkler blowout and winterization service runs on that calendar.

How do I get winter alerts in western Montana?

Use more than one channel. NOAA Weather Radio All Hazards broadcasts official warnings, watches and forecasts 24 hours a day, 7 days a week, from more than 1,000 transmitters covering all 50 states. Wireless Emergency Alerts on phones need no signup, but the NWS sends only certain alerts that way. Its list includes snow squall warnings among winter hazards, while Winter Storm, Blizzard and Ice Storm Warnings are not on the WEA list. So a phone that stays silent does not mean there is no winter warning.

For details, the NWS Missoula website shows current hazards by area, and its Area Forecast Discussion explains the forecast in plain language. We do not list numeric warning thresholds for western Montana here, because we could not find a published NWS Missoula criteria page to cite; the alert text states the expected amounts for each event.

How do alerts fit into a snow service plan?

They set the rhythm. A watch is the time to confirm the plan and check materials, a warning means expecting repeat passes, and an advisory for freezing precipitation puts entrances and walks first. Our routes themselves are set before the season, so nobody is negotiating a route in the middle of a storm.

Our snow and 24-hour storm services cover homes, businesses, HOAs and private roads across Missoula and Ravalli counties. This guide is part of our Montana Winter Property Guide, and winter storm types in western Montana explains what is behind each alert. Call HJ Property Care & Tree Service at (406) 215-7319 or request a free estimate for winter service in Missoula and the Bitterroot Valley.

More resources