Oregon Snow, Mixed Precipitation, and Rain Forecast
Follow the rain–snow line across Oregon and zoom into Mt. Hood, Santiam, Willamette, Siskiyou, and Blue Mountain passes with 49 hourly frames from the latest complete 48-hour HRRR run.
Loading the snow forecast…
Loading 49 hourly HRRR frames and the 3 km grid.
Methodology
One model, native precipitation types
NOAA HRRR is the best fit for this first map because it resolves Oregon at 3 km, updates hourly, and publishes categorical rain, snow, ice-pellet, and freezing-rain fields with precipitation rate.
Snow is white, rain is green, sleet is purple, freezing rain is hot pink, and overlapping model flags are amber. A block is shown only when HRRR also predicts measurable precipitation, which avoids painting dry areas from a stray categorical flag.
HRRR describes the atmosphere, not pavement. Elevation changes inside a block, warm road surfaces, and narrow transition zones can all produce different travel conditions than the map color. Check TripCheck before travel.
FAQ
Oregon snow forecast questions
What does “mixed” mean on this map?
Mixed means more than one HRRR surface precipitation flag is active in the same block. Sleet and freezing rain have their own colors when HRRR identifies them separately. It is a planning signal, not a road-condition report.
Why can Oregon valleys get rain while the passes get snow?
Elevation and the vertical temperature profile change quickly across Oregon. The 3 km blocks make the modeled rain–snow transition visible instead of assigning one precipitation type to the whole state.
How far ahead does the map go?
The four extended HRRR runs each day provide hourly guidance through forecast hour 48. Other hourly HRRR runs stop at hour 18, so this page uses the latest complete extended run.
Is this an official road forecast?
No. HRRR is weather-model guidance. Check ODOT TripCheck and National Weather Service alerts before winter travel, especially over mountain passes.