Keep the trip. The big fire near you is on the far side of Mt Hood, and in late August the wind on your side of the mountains almost always blows from the ocean toward the fire, not from the fire toward the house — which is why the monitor eight miles away reads Good today even with 85,000 acres burning nearby.
Our best guess for the worst of your three days is around 32, which a phone app calls 'Good': maybe a faint haze on the ridgelines, fine for kids, hikes and dinner outside. What would spoil it is an east wind pushing that plume back over the crest, or one of the smaller uncontained fires south and west of you growing into something serious, and you would see either coming two or three days out.
If we ran this weekend 100 times, here is how they would split. Hover a row to pick it out of the dots.
| 5 in 1054% | Clear weekend AQI 0-50 Blue sky, maybe a milky band on the eastern horizon in the morning that burns off. Nobody mentions smoke after the first hour. | nothing |
| 3 in 1026% | Hazy but fine AQI 50-100 Flat white sky, the mountain is a faint outline, you can smell woodsmoke on the morning porch. Sunsets are orange. Outdoor time is fine; a couple of people with asthma notice it. | Take the long hike in the morning before the valley heats up, close windows overnight, run a purifier in the sleeping rooms. |
| 1 in 1011% | One smoky day AQI 100-150 You can't see Mt Hood at all, visibility down the Sandy valley under a couple of miles, the sun is a red disc, eyes and throat sting after an hour outside. | Cancel the hiking day, run box-fan filters indoors, masks for anyone outside, keep kids and anyone with asthma in. |
| 1 in 109% | Real smoke episode AQI 150+ Ash or smoke smell indoors, headlights on at midday, a haze layer you can taste. Likely accompanied by fire news, possibly a Level 1 evacuation notice somewhere in the county. | Consider leaving west toward Portland or the coast, or cutting the trip short; check US-26 status before driving. |
Fires near the house, drawn at their real shape from the federal perimeter data, over USGS terrain. Dashed rings are distance from the house; the shaded wedge is the only direction an east wind could carry smoke here from. Point at a fire for its details.
Solid dots are fires too small to draw at this scale but whose size is known. A dashed circle would mean a fire that has been located but has no published perimeter - size unknown, not small.
Beyond this frame, and too far to threaten the house but close enough to add regional haze: Bench (67,071 acres, 45.5 mi SSE), Ten Mile (4,834 acres, 56.7 mi SE), Beachcomb (2,346 acres, 49.5 mi SSE), High Lava (1,211 acres, 38.9 mi NNW).
An outline is only as current as the last mapping flight, which is not the same as when this page refreshed. Outlines flown — Grasshopper Aug 11 · Austin Aug 10 · Mitchell Aug 9 · The Narrows Aug 8. The oldest is The Narrows, 5 days behind. Acreage and containment are refreshed far more often than the outlines are re-flown — those figures were last updated Aug 13, 8:34 AM, so a fire may already be larger than the shape drawn for it.
Terrain: USGS 3DEP (public domain). Roads and water: © OpenStreetMap contributors (ODbL). Fire perimeters: NIFC.
Want to check it yourself, or see the rest of the state? The Oregonian's wildfire tracker is live and updates every 15 minutes.
The long-range ensembles show less east-wind risk than a normal year — weak evidence, but pointing the right way.
Caveat: this counts days whose dominant wind is easterly, which at a valley site also picks up ordinary overnight down-valley drainage, not only the Gorge-outflow events that actually carry smoke. Forecast and base rate are measured the same way, so the gap is the meaningful part; the absolute percentages are not a chance-of-smoke.
It is not one cut-off. Five sources arrive on five different dates, and the darker the strip, the more of them cover your weekend. Hover any day for the count.
= Since 2026-08-10 the forecast has moved steady (+2 on the likely worst day) across 4 daily updates. Shading above shows source coverage, not this movement - hover a past day to see what we said that morning.
| now | Fire size & containment how big the fires are and whether they are being held |
| now | Long-range ensembles (GEFS 0.5 + GEM) wind direction, 52 members · reaches 32 days out |
| Aug 15 | ECMWF ensemble (51 members) wind direction, the sharpest ensemble · reaches 13 days out |
| now | Deterministic weather (16-day) day-by-day wind and temperature · reaches 15 days out |
| Aug 22 | Air-quality / smoke model (CAMS) actual AQI at the house · reaches 6 days out |
The controlling fact is geometry plus the prevailing wind: Grasshopper, the only large fire in range at 85,114 acres, sits 17.4 miles due east, while Mt Hood's crest and the standard late-August onshore/marine regime both lie between it and the house — which is why the monitor 8.7 miles away reads 13 today with that fire fully active. A fire that size at 20% containment will absolutely still be producing smoke on Aug 28-30 (Oregon fires this large routinely burn into late September and are ended by rain, not by lines), so this is a transport question, not a source question, and transport currently and climatologically points the wrong way for smoke to reach Welches. I did not, however, take the terrain-shield argument at face value: Austin (1,430 acres, 0% contained, 19.4 mi S), Mitchell (12.5 mi S), The Narrows (14 mi SSW), Regan Hill (17.8 mi W) and High Lava (1,211 acres, 0% contained, 38.9 mi NNW) are all on the house's side of the crest, with High Lava roughly upwind in the climatological NW flow — those, plus a brand-new ignition in the Sandy or Clackamas drainage over the next fifteen days, are the realistic paths to a bad weekend, not Grasshopper. Against that, the 24-hour averaging window is a genuine dampener: a smoky morning from nocturnal valley drainage, which is what 'patchy smoke then areas of fog' already describes, gets diluted by a clean afternoon and rarely pushes the daily average over 100 without sustained synoptic transport.
A normal late August here is Clear - median AQI 12 across the last 4 years. On these exact dates: 2025: 16 · 2024: 10 · 2023: 11 · 2022: 11.
We are forecasting a worst day of 44, 32 points above that base rate. That departure rests entirely on the reasoning above; judge it for yourself.
| 12.5 mi | Mitchell S | 16 acres |
| 14.0 mi | The Narrows SSW | 2 acres |
| 17.4 mi | Grasshopper E | 85,114 acres · 20% contained |
| 17.8 mi | Regan Hill W | size not yet reported |
| 19.4 mi | Austin S | 1,430 acres · 0% contained |
| 20.4 mi | Austin Non-Stat S | size not yet reported |
| 27.1 mi | Gorton Creek NNE | size not yet reported |
The biggest hole in this forecast: 3 of the nearby fires (Regan Hill, Austin Non-Stat, Gorton Creek) have no size reported yet. Whether those are 300-acre creepers or 20,000-acre runners is most of the answer.
If the weekend is clean you carried masks for nothing. If it is not, this is the difference between a bad weekend and a ruined one.
| Sandy | 19.4 mi |
| Brightwood | 15.5 mi |
| Welches | 14.3 mi |
Distance from each point on the drive in to the nearest fire. TripCheck is the authority on closures.
Fire perimeters from NIFC, evacuation zones from Oregon OEM, weather and alerts from NWS, air quality from AirNow (Multorpor, 8.7 mi away). The forecast is judged by Claude Opus 5 on the live data above, sampled 5 times and pooled conservatively.
It is a judgement, never scored against an outcome. Nobody forecasts smoke this far out: NOAA's smoke model runs 48 hours and the EPA's air-quality forecast is for tomorrow. Two-to-six weeks ahead is what meteorologists call the predictability desert. Anyone giving you a number for the trip right now - us included - is giving you a base rate with a story attached.
AQI here means the highest 24-hour PM2.5 value touching a day, at the house, on the local monitor scale - the same thing your phone shows. The model's own restatement of the target: “I am forecasting the US AQI for PM2.5 as a 24-hour average — the number a phone app shows — at the Welches / Mt Hood Village house, taking for each calendar day the highest 24-hour value touching that day, on the local-monitor scale already calibrated in the evidence pack (no further bias correction applied by me). The headline figure is the single worst of those three daily values across Aug 28, 29 and 30, not their average.”
Updated daily at 5am. A convenience, not an authority -
if officials issue an evacuation order, follow it.