Mountain conditions
How to read a ski resort snow report before you go
Which snow number are you looking at?
New snow is an accumulation over a stated period at a measurement location. Base depth describes the snowpack depth at the reported location. A season total is accumulated reported snowfall over the season. A forecast estimates future conditions. Do not substitute one for another when deciding whether to travel.
Read the operator’s definitions. An overnight total may use a different start time from a 24-hour total, and a snow-stake camera may have a scheduled reset. Adding overlapping totals double-counts snow. If the reporting interval is missing, treat comparisons with another mountain cautiously.
A worked example: the bigger number may be older
Mountain A reports 8 inches over 48 hours at 6 a.m. Mountain B reports 5 inches over 24 hours at 7 a.m. You cannot conclude that A had more snow last night. The periods differ and both totals can include snow that fell before the most recent overnight window.
Write each observation as amount + period + location + timestamp. For example: “5 inches / 24 hours / mid-mountain stake / 7 a.m.” That small habit makes it easier to spot old reports, overlapping totals and unmatched elevations. The figures here are illustrative.
| Measure | Useful for | Cannot establish |
|---|---|---|
| New snow | Recent accumulation at a reported point | Coverage on every run |
| Base depth | Depth at a measuring location | How much fell overnight |
| Forecast snowfall | Expected future accumulation | A measured result |
| Open terrain | Operator-reported availability | Future opening guarantees |
Why can the base be wet while the summit gets snow?
Elevation affects the rain–snow transition. The National Weather Service’s snow-level guidance describes the elevation where precipitation changes toward snow; this is not identical to the atmospheric freezing level. A mountain can span that transition.
Compare the forecast snow level with the elevations you expect to ski. If lower and upper terrain sit on opposite sides, do not apply a summit snowfall forecast to the entire resort. Use a mountain-specific forecast and read the forecaster’s discussion when available.
Source: National Weather Service: snow-level definition and methodology ↗
Does 8 mm of precipitation mean 8 cm of new snow?
No. A precipitation amount is not a snow-depth forecast. MET Norway lists precipitation in millimetres for the stated period; its air temperature describes a point two metres above the ground. In an invented example, 8 mm of precipitation and a subfreezing temperature do not establish 8 cm of snowfall. This site keeps that field labelled precipitation.
NWS guidance separates the liquid amount, precipitation type and snow-to-liquid ratio when forecasting snow. A single temperature does not resolve all three. For U.S. mountains, use the NWS desk’s explicit new-snow field when available instead of inventing a conversion from the global weather desk.
Source: MET Norway: precipitation, temperature and point-forecast variables ↗; National Weather Service: snow-level definition and methodology ↗
Choose a U.S. mountain and inspect published new-snow windows →
A worked forecast example: which snow amounts can you add?
NWS snow amounts describe new accumulation over six-hour periods. Consider invented forecasts for one point, one issue and one UTC day: 2 inches for 06:00–12:00 and 3 inches for 12:00–18:00. The adjacent, complete windows total 5 inches for 06:00–18:00. They estimate future snowfall; they do not measure what has fallen.
If another display shows 5 inches for that same 06:00–18:00 span, it already includes those hours. Adding 2 + 3 + 5 would count them twice. If the 12:00–18:00 window is missing, the known 2 inches is only a partial result. It does not establish a 2-inch twelve-hour total or a zero for the missing period.
The same discipline applies to MET precipitation: next-hour and next-six-hour amounts starting at the same instant overlap. Keep units, start, end and time zone attached to every amount. Our desks withhold a complete total where a required published interval is absent.
Source: National Weather Service: six-hour snow-amount and precipitation definitions ↗; MET Norway: update time, forecast times and overlapping aggregation periods ↗
What should you do when mountain forecasts disagree?
Before comparing amounts, line up the forecast issue, valid hours, units and point location. MET separates its update timestamp from the future times being forecast; an hourly temperature and a six-hour accumulation also describe different spans. A newer forecast may cover a different window rather than simply predict more snow.
Check the point’s displayed elevation against the terrain you plan to ski. A hypothetical 900 m valley point and a 2,000 m upper mountain are not interchangeable. MET warns that coarse topography can affect temperature corrections in hilly terrain. Keep those differences visible instead of averaging unmatched amounts or picking the largest number.
Source: MET Norway: point elevation and temperature correction ↗; MET Norway: update time, forecast times and overlapping aggregation periods ↗
Inspect the point, elevation and source time in global mountain weather →
Will the reported snow actually be available to ski?
Use the operator’s lift and terrain status to answer that question. A weather forecast does not establish whether a particular lift will run or when a run will open. Check the terrain relevant to your ability and planned lesson, rather than only a resort-wide percentage.
Look at a camera timestamp before trusting the image. A sunny archived image and a fresh weather report can coexist on the same page. Cameras add visual context at one viewpoint; they do not establish conditions across a mountain.
Use a five-minute departure check
First, open the mountain’s official report and read its update time. Second, note the new-snow interval and measuring location. Third, check the forecast at the relevant elevation. Fourth, check lifts and terrain. Fifth, confirm your route, parking or transit with the responsible operator.
Save the links, not just screenshots. Reopen them close to departure because conditions and operations can change. If reports conflict, keep the conflicting timestamp or location visible instead of blending them into a single confident claim.
For seasonal trip planning, return to the winter outlook and your full budget. A single storm report is useful for an upcoming day; it is not evidence that the same mountain will be the best choice months later.
Straight answers
- Can I add overnight snow to the 24-hour total?
- Only if the operator explicitly defines them as non-overlapping periods. Overnight snow is often already part of the 24-hour total.
- Is the town weather forecast enough for skiing?
- Check a forecast for the mountain and relevant elevation. Town and mountain conditions can differ, especially when the rain–snow transition lies between them.
- Is precipitation in millimetres the same as snowfall in centimetres?
- No. Keep the original measure and interval. A snowfall conversion needs evidence about precipitation type and snow-to-liquid ratio; one air temperature is not enough.
- Does an unavailable snow window mean no snow is forecast?
- No. An absent value is unknown in this display. Only an explicit published zero supports a zero for its stated point and period.
Sources & method
Source references checked . This researched explainer combines the references below with original planning examples. Illustrative prices and snow amounts are not current offers or observations. It does not claim first-hand resort reporting.
- National Weather Service: snow-level definition and methodology ↗
- MET Norway: precipitation, temperature and point-forecast variables ↗
- National Weather Service: six-hour snow-amount and precipitation definitions ↗
- MET Norway: point elevation and temperature correction ↗
- MET Norway: update time, forecast times and overlapping aggregation periods ↗