Most late-August weekends at this house are clear or mildly hazy, because the usual wind comes off the ocean and pushes smoke inland away from you. The risk this year is different only because two big fires sat within twenty miles — one to the south on your side of the mountains, one to the east — and both were still smoldering with open edges in late August.
If the wind turns around and blows from the east, or drains down the valley overnight, you could get a day where the air looks milky, smells like campfire, and reads around 100-200 on a phone air-quality app; otherwise expect 30-60, which is fine for everyone except the most sensitive.
If we ran this weekend 100 times, here is how they would split. Hover a row to pick it out of the dots.
| 3 in 1028% | Clear weekend AQI 0-50 Mt Hood sharp and blue-white from the deck, clean pine smell, maybe a faint brown band low on the eastern horizon in the afternoon; nobody notices anything. | nothing |
| 4 in 1040% | Hazy but fine AQI 50-100 Milky sky, flat light, the ridgeline looks soft instead of sharp, a campfire smell at breakfast that burns off by noon; the one asthmatic in the group notices on an uphill hike. | Weak overnight drainage of smoke down the Sandy/Zigzag valley that mixes out by midday; kids and hikers fine, sensitive members take it easy in the morning. |
| 2 in 1017% | One smoky day AQI 100-150 Sun is an orange disk you can look at, the far side of the valley disappears, eyes and throat scratchy, ash-free but smells like a wet campfire indoors too. | A day or two of east/offshore gradient pulls smoke from Grasshopper's side through the passes, or Austin's north flank runs and smoke comes straight up the valley; everyone shifts to indoor plans for a day. |
| 1 in 1015% | Real smoke episode AQI 150+ Grey-brown air you can taste, visibility under a mile, headlights on at midday, headaches by evening, smoke seeping into the house through every gap. | A ridge builds, offshore east flow sets up for 2-3 days, a nearby fire makes a wind-driven run, and the smoke pools under a nighttime inversion in the valley; the weekend becomes an indoors-with-purifiers weekend and sensitive people should not come. |
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), High Lava (2,899 acres, 37.0 mi N).
An outline is only as current as the last mapping flight, which is not the same as when this page refreshed. Outlines flown — Grasshopper Sep 15 · Austin Sep 16 · The Narrows Sep 15. The oldest is The Narrows, 32 days behind. Acreage and containment are refreshed far more often than the outlines are re-flown — those figures were last updated Sep 29, 4:26 PM, 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.
Long-range wind signal unavailable this run.
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 worse (+23 on the likely worst day) across 68 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 |
| now | 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 |
| now | Air-quality / smoke model (CAMS) actual AQI at the house · reaches 6 days out |
The house sits on the west slope in the Sandy/Zigzag valley, where the dominant late-August pattern is onshore westerly flow that carries smoke away from it; that is why the 2022-2025 base rate for this exact window shows 0 of 28 days over 100 and a worst day of 62. What is not in that base rate is the proximity of this year's fires: Grasshopper (94k acres) at 17 miles east is mostly across the crest and needs an offshore gradient to reach the house, but Austin (12.9k acres) at 18 miles south is on the SAME side of the crest with no terrain between it and the Sandy drainage, so ordinary southerly or up-valley flow suffices — the Mt Hood 'shield' in the terrain note protects against one of these fires, not both. Both were only at 98% containment as of September 17, which implies open, smoldering edges through late August in a record-drought year with fully cured fuels and PL-5 resource constraints, exactly the setup where a single wind-driven afternoon run produces one bad 24-hour average rather than a smoky fortnight. The ensemble field for east wind is null, so I cannot claim evidence either for or against the offshore reversal the bad case needs, and I fall back to the 31% climatological offshore rate with no departure — which is why the 150+ scenario stays near 0.20 instead of being inflated.
A normal late August here is Clear - median AQI 34 across the last 4 years. On these exact dates: 2025: 44 · 2024: 28 · 2023: 30 · 2022: 30.
We are forecasting a worst day of 65, 31 points above that base rate. That departure rests entirely on the reasoning above; judge it for yourself.
| 13.9 mi | The Narrows SSW | 304 acres · 98% contained |
| 15.9 mi | Latigo Lane WNW | size not yet reported |
| 16.5 mi | Timber Lake/Ripplebrook Admin Rx - West SSW | size not yet reported |
| 16.5 mi | Fawn Stew Piles Rx - West SSW | size not yet reported |
| 17.2 mi | Podunk Admin Rx - West SW | size not yet reported |
| 17.4 mi | Grasshopper E | 93,971 acres · 98% contained |
| 18.3 mi | Austin S | 12,888 acres · 98% contained |
The biggest hole in this forecast: 4 of the nearby fires (Latigo Lane, Timber Lake/Ripplebrook Admin Rx - West, Fawn Stew Piles Rx - West and 1 more) 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 | 2.7 mi |
| Brightwood | 7.1 mi |
| Welches | 13.6 mi |
Distance from each point on the drive in to the nearest fire. TripCheck is the authority on closures.
Ranked by how bad these dates have historically been at each place. The coast is not just cleaner today — it sits upwind of everything burning, so it only smokes during an east-wind reversal, which is the same event that would smoke out the house.
| Place | Bad day / typical | Now | Official forecast | Next 5 days | Nearest fire |
| Newport coast | 20 / 17 | 12 Clear | Good | ▲ worsening | 101 mi · Austin |
| Astoria coast | 21 / 18 | 10 Clear | Good | ▲ worsening | 84 mi · High Lava |
| Long Beach, WA coast | 22 / 19 | 10 Clear | Good | ▲ worsening | 97 mi · High Lava |
| Welches / Mt Hood booked | 23 / 17 | 27 Clear | Good | ▲ worsening | 14 mi · The Narrows |
| Manzanita coast | 29 / 27 | 29 Clear | — | ▲ worsening | 87 mi · High Lava |
| Cannon Beach coast | 31 / 27 | 29 Clear | — | ▲ worsening | 88 mi · High Lava |
| Pacific City coast | 31 / 28 | 29 Clear | — | ▲ worsening | 91 mi · The Narrows |
| Hood River east of crest | 42 / 28 | 39 Clear | Good | ▲ worsening | 21 mi · Grasshopper |
| Portland valley | 47 / 38 | 65 Hazy | Good | – steady | 36 mi · High Lava |
| Silver Falls valley | 53 / 39 | 54 Hazy | — | – steady | 31 mi · Austin |
| McMinnville valley | 55 / 38 | 44 Clear | Good | ▲ worsening | 54 mi · The Narrows |
| Bend east of crest | 58 / 34 | 59 Hazy | — | – steady | 36 mi · Bench |
| Field | Period it covers | What it is |
| Air right now | 10/17/26 4:00 PDT | Nearest EPA/AirNow ground monitor to each place, within 45 miles airnow.gov |
| Official forecast | issued 10/17/26 by Washington Department of Ecology | Next published outlook for that reporting area — a human forecaster's call Oregon DEQ via AirNow |
| Next 5 days | today's model run, covering 2026-10-21 | Direction only. Copernicus CAMS global air-quality model open-meteo.com |
| Bad day / typical | Aug 26 – Sep 1 in 2022, 2023, 2024, 2025 (28 days each) | CAMS reanalysis for those exact dates, then converted to the monitor scale open-meteo.com |
| Scale conversion | median of 14 daily model-vs-monitor pairs, 2026-10-01 to 2026-10-14 | Median of daily model-vs-monitor ratios — the bias differs by place, from 0.37 on the coast to 0.768 inland AirNow daily archive |
| Nearest fire | queried Oct 17 5:01 AM | Perimeter polygons of fires over 100 acres, distance to the burned edge NIFC WFIGS |
Every AQI figure above is on the ground-monitor scale — the same thing your phone shows. n/a means the model and the monitors disagree so sharply at that spot that we cannot honestly place it on that scale (steep terrain inside a coarse model grid cell — the Gorge is the usual culprit); those rows are sorted by today’s reading instead.
Fire perimeters from NIFC, evacuation zones from Oregon OEM, weather and alerts from NWS, air quality from AirNow (Estacada, 18.3 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.
How thin the history is. The air-quality record for this spot begins in 2022, so "normal" here is built from just 4 years (2022, 2023, 2024, 2025). In those 28 sampled days the worst single day was AQI 62, and none reached 100.
That record has never seen a bad Oregon smoke year — not 2020, when Portland sat above AQI 500 for days, nor 2017, 2018 or 2021. So the base rate below is drawn entirely from calm years, and the upper end of our range is an estimate rather than something history has shown us. It is the main reason not to read the good news too confidently.
Are these forecasts any good? Across 315 scored forecast-days, the air-quality model beat both simple baselines at 1 of 5 lead times. Where it does not, this page should not be trusted to out-guess them either.
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 single highest 24-hour-average US AQI for PM2.5 that touches any one of August 28, 29 or 30, 2026 at the house in Welches, Oregon — the worst day, not the three-day mean — expressed on the local monitor scale that a phone app like AirNow would display, with the model-to-monitor calibration already applied in the evidence and no further bias correction of my own.”
Updated daily at 5am. A convenience, not an authority -
if officials issue an evacuation order, follow it.