Fires are burning both east of Mt Hood and, more importantly, within 12-20 miles south of the house on the same side of the mountain, so some haze during the trip is the base case rather than a surprise. The nearest monitor is currently reading in the upper 'Good' range even with all of that burning, and the usual late-August pattern at Welches is smoky mornings that clear as westerly ocean air pushes up the valley each afternoon.
Plan on going, bring an air purifier and N95s, and hold one indoor-friendly day in reserve in case a wind shift parks smoke in the Sandy/Zigzag valley.
If we ran this weekend 100 times, here is how they would split. Hover a row to pick it out of the dots.
| 4 in 1039% | Clear weekend AQI 0-50 Blue sky, Mt Hood sharp all three days, maybe a thin morning haze that burns off by 10am. | nothing |
| 4 in 1038% | Hazy but fine AQI 50-100 Milky white sky, faint campfire smell at dawn, the ridgelines look flat and washed out, sunsets orange. Most people feel nothing; a couple of asthmatics notice it. | Do hikes in the morning or late afternoon, run a purifier in the sleeping rooms overnight, keep windows shut before sunrise. |
| 1 in 1014% | One smoky day AQI 100-150 One day you cannot see the far side of the valley, eyes sting outdoors, everyone's phone app is orange. The other two days are noticeably better. | That day becomes an indoor day - cards, cooking, a drive west toward Sandy or Portland where the air is usually cleaner. |
| 1 in 109% | Real smoke episode AQI 150+ Brown-grey air all day, sun is a red disc, headaches by afternoon, kids and older folks feel it indoors too. Smoke does not lift in the afternoon. | Leave early or relocate to the coast/valley; the house is not a place to spend a weekend in that air without serious filtration. |
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 (1,359 acres, 38.6 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 16 · Austin Aug 16 · The Narrows Aug 12 · Mitchell Aug 16. 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 17, 12:14 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 (+16 on the likely worst day) across 9 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 |
Check the bearings before assuming Mt Hood protects this house: Grasshopper (90,668 acres, 49% contained) is east and does sit behind the crest, but Mitchell, The Narrows, and Austin are 12-20 miles south and southwest - the same side of the mountains as Welches, in the Salmon and Clackamas drainages, with no terrain barrier at all. That means the dominant mechanism is not a dramatic crest-crossing plume but ordinary nocturnal drainage flow pooling nearby smoke in the Sandy/Zigzag valley overnight, which is exactly what produces the 41 the monitor is reading right now on a calm day with winds not even pointed at the house. For the weekend to be clean, the usual marine push has to keep westerly onshore flow ventilating the valley each afternoon, which is the single most common late-August pattern here and is why the base case is haze rather than emergency. For it to be bad, winds have to turn easterly or southerly for a day or two - a thermal trough or dry frontal passage - which both fans the uncontained southern fires and tips Grasshopper's smoke back over the crest. Oregon fires of Grasshopper's size routinely persist into late September until season-ending rain, so containment reaching 100% before the trip is not the realistic good path; containment reaching 65-75% with a quiet interior is.
A normal late August here is Clear - median AQI 17 across the last 4 years. On these exact dates: 2025: 22 · 2024: 14 · 2023: 15 · 2022: 15.
We are forecasting a worst day of 58, 41 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 | 89 acres · 0% contained |
| 17.4 mi | Grasshopper E | 90,668 acres · 49% contained |
| 19.4 mi | Austin S | 2,678 acres · 0% contained |
| 20.4 mi | Austin Non-Stat S | size not yet reported |
| 38.6 mi | High Lava NNW | 1,359 acres · 8% contained |
| 45.5 mi | Bench SSE | 67,071 acres · 90% 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 | 19.4 mi |
| Brightwood | 15.6 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 | 32 Clear | Good | – steady | 105 mi · Austin |
| Manzanita coast | 22 / 21 | 36 Clear | Good | – steady | 87 mi · High Lava |
| Cannon Beach coast | 23 / 20 | 36 Clear | Good | – steady | 88 mi · High Lava |
| Pacific City coast | 23 / 20 | 36 Clear | Good | – steady | 98 mi · Austin |
| Astoria coast | 26 / 23 | 20 Clear | Good | – steady | 84 mi · High Lava |
| Long Beach, WA coast | 27 / 24 | 20 Clear | Good | – steady | 97 mi · High Lava |
| Welches / Mt Hood booked | 37 / 28 | 47 Clear | Moderate | – steady | 17 mi · Grasshopper |
| Silver Falls valley | 45 / 33 | 52 Hazy | Moderate | – steady | 35 mi · Austin |
| Portland valley | 48 / 38 | 59 Hazy | Good | – steady | 36 mi · High Lava |
| McMinnville valley | 53 / 37 | 54 Hazy | Good | – steady | 61 mi · Austin |
| Bend east of crest | 119 / 70 | 140 Smoky | Moderate | ▲ worsening | 22 mi · Akawa Butte |
| Hood River east of crest | n/a | 48 Clear | Sensitive groups | – steady | 21 mi · Grasshopper |
| Field | Period it covers | What it is |
| Air right now | 08/18/26 4:00 PDT | Nearest EPA/AirNow ground monitor to each place, within 45 miles airnow.gov |
| Official forecast | issued 08/18/26 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 2026-08-22 | 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 18 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 (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 31, 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 15 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 highest 24-hour-average US AQI for PM2.5 that touches each calendar day at the house in Welches, on the local monitor scale a phone app would display (the same scale as the 41 currently observed at Multorpor), not the raw model scale - and the headline number is the single worst of the three trip days, not their average.”
Updated daily at 5am. A convenience, not an authority -
if officials issue an evacuation order, follow it.