Large fires are burning within twenty miles of the house on both the east and south sides, and they will still be burning during your trip — but the house sits on the ocean side of the mountain, where the usual sea breeze pushes that smoke away most days. Our best guess for the worst day of the weekend is a reading around 65, which is 'moderate': hazy light, maybe a campfire smell, uncomfortable for asthmatics and fine for most people.
The thing that would actually wreck the weekend is an east wind, which funnels smoke from the 88,000-acre Grasshopper fire straight down Highway 26 into the Welches valley — and you'd see that coming about two days ahead.
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 1033% | Clear weekend AQI 0-50 Blue sky, sharp view of Mt Hood, maybe faint haze at sunset. Nobody thinks about smoke. | nothing |
| 4 in 1042% | Hazy but fine AQI 50-100 Milky white sky, orange sun, faint campfire smell that's worst at dawn before the valley air mixes out. Ridges 10 miles off go flat and gray. | Kids and anyone with asthma keep the hard exercise short; close windows overnight and run a purifier in the main sleeping room. |
| 1 in 1014% | One smoky day AQI 100-150 Visible smoke layer in the valley, sun a dim disc, you can taste it. Smells like smoke inside the house within an hour of opening a door. | That day moves indoors — no hikes, no river time. Masks for anyone going outside; drive west toward Sandy/Portland for the afternoon if you need out. |
| 1 in 1010% | Real smoke episode AQI 150+ Gray-brown murk, headlights on at noon, sore throats and headaches by evening. Ash possible if a fire is close. | Cut the trip short or relocate to the coast/Portland. Check TripCheck before driving; expect Level 1 evacuation chatter in the corridor. |
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 (1,251 acres, 38.8 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 12 · Mitchell Aug 9. The oldest is Mitchell, 7 days behind. Acreage and containment are refreshed far more often than the outlines are re-flown — those figures were last updated Aug 15, 5:08 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.
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 worse (+22 on the likely worst day) across 8 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 |
| Aug 22 | Air-quality / smoke model (CAMS) actual AQI at the house · reaches 6 days out |
The dominant source is Grasshopper — 87,820 acres and 37% contained, 17 miles due east — and in a year with 96% of Oregon in drought, record-low snowpack, and PL 5 since July 18, that fire will still be smoking on Aug 28-30 regardless of containment progress; containment mostly bounds growth, not smoke output. What separates a fine weekend from a bad one is transport, not the fire: the house sits on the west slope at ~1,200 ft, where the prevailing summer onshore marine flow pushes crest smoke east and keeps this location's 4-year record at 0 of 28 days over 100. The failure mode is an offshore gradient flip, which sends east wind down through Barlow Pass and Government Camp straight along the US-26/Zigzag corridor into Welches, then leaves it pooled under the nocturnal valley inversion — that mechanism produces multi-day 100-200 episodes, and it becomes more common as August turns to September. I am not assuming Mt Hood shields the house: Austin (2,016 acres, 0% contained) and Mitchell sit 12-19 miles due south on the same side of the crest, and High Lava sits 39 miles NNW, so south flow ahead of a trough or northerly flow are both live delivery routes without any east wind at all. Local air is currently running 41 against a typical 24 with an active NWS air quality alert, so the ambient floor is already about 1.7x normal, and I have added a max-of-three-days uplift on top of that rather than a second 'bad year' factor.
A normal late August here is Clear - median AQI 29 across the last 4 years. On these exact dates: 2025: 38 · 2024: 24 · 2023: 26 · 2022: 26.
We are forecasting a worst day of 64, 35 points above that base rate. That departure rests entirely on the reasoning above; judge it for yourself.
| 12.5 mi | Mitchell S | 16 acres |
| 17.4 mi | Grasshopper E | 87,820 acres · 37% contained |
| 19.4 mi | Austin S | 2,016 acres · 0% contained |
| 20.4 mi | Austin Non-Stat S | size not yet reported |
| 38.8 mi | High Lava NNW | 1,251 acres · 8% contained |
| 45.5 mi | Bench SSE | 67,071 acres · 86% contained |
| 49.5 mi | Beachcomb SSE | 2,346 acres · 100% contained |
The biggest hole in this forecast: 1 of the nearby fires (Austin Non-Stat) 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 | 22.8 mi |
| Brightwood | 17.5 mi |
| Welches | 14.3 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 | 105 mi · Austin |
| Manzanita coast | 22 / 21 | 19 Clear | Good | – steady | 87 mi · High Lava |
| Cannon Beach coast | 23 / 20 | 19 Clear | Good | – steady | 88 mi · High Lava |
| Pacific City coast | 23 / 20 | 19 Clear | Good | – steady | 98 mi · Austin |
| Astoria coast | 26 / 23 | 15 Clear | Good | – steady | 84 mi · High Lava |
| Long Beach, WA coast | 27 / 24 | 15 Clear | Good | – steady | 97 mi · High Lava |
| Welches / Mt Hood booked | 37 / 28 | 19 Clear | Sensitive groups | – steady | 17 mi · Grasshopper |
| Silver Falls valley | 45 / 33 | 56 Hazy | Moderate | – steady | 35 mi · Austin |
| Portland valley | 48 / 38 | 38 Clear | Moderate | – steady | 36 mi · High Lava |
| McMinnville valley | 53 / 37 | 31 Clear | Moderate | – steady | 61 mi · Austin |
| Bend east of crest | 119 / 70 | 155 Bad | Moderate | – steady | 22 mi · Akawa Butte |
| Hood River east of crest | n/a | 36 Clear | Sensitive groups | – steady | 21 mi · Grasshopper |
| Field | Period it covers | What it is |
| Air right now | 08/17/26 4:00 PDT | Nearest EPA/AirNow ground monitor to each place, within 45 miles airnow.gov |
| Official forecast | issued 08/17/26 by Oregon Dept. of Environmental Quality | Next published outlook for that reporting area — a human forecaster's call Oregon DEQ via AirNow |
| Next 5 days | today's model run, covering 2026-08-21 | 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, 2026-07-31 to 2026-08-13 | Median of daily model-vs-monitor ratios — the bias differs by place, from 0.375 on the coast to 1.056 inland AirNow daily archive |
| Nearest fire | queried Aug 17 5:00 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 (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.
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 54, 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 10 scored forecast-days, the air-quality model beat both simple baselines at 2 of 4 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 highest 24-hour-average US AQI for PM2.5 that touches each calendar day at the Welches house, on the local monitor scale — what an AirNow or phone app would show at the nearest station, not the raw model scale — and my headline number is the single worst of the three days 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.