Mt Hood · Aug 28-30 · -58 days out Updated Sun Oct 25, 5:00 AM · refreshes daily at 5am

Still on, but worth watching.

6 in 10chance the weekend is fine - clear or lightly hazy

First, a flag: the trip window you asked about (August 28-30, 2026) ended almost two months ago, and the fire and air-quality numbers in this pack were measured in mid-September and late October, after the fact. Treating it as a genuine forecast made with August information, the honest answer is that most versions of that weekend were hazy-but-usable, with a real but minority chance of one genuinely smoky day.

The worst single day was more likely to land in the moderate range than in the unhealthy range, but there were three large fires inside twenty miles and two of them were on the same side of the crest as the house, so a bad day was never off the table.

Known now5 of 5 forecast sources already cover your dates

No horizonFire size and containment are observations, not forecasts — they can move this on any day

Decide byAug 25

What would change this

Evacuation zone at the housenone
US-26 open, Portland to Welchesopen
Air at Estacada49 · Clear
Nearest fire outside 10 miles13.9 mi · The Narrows
Wind pushing smoke our wayno - ESE at 1 mph

So what are the odds?

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 1029%	Clear weekend AQI 0-50 Mt Hood sharp and clean from the deck, blue sky, no smell of smoke, sunsets normal colour. Marine air, cool mornings, maybe fog in the Sandy drainage.	nothing
3 in 1032%	Hazy but fine AQI 50-100 Milky white sky, the mountain visible but washed out, orange sunset, a faint campfire smell in the morning that burns off by noon. Fine for hiking, river time, kids outside. Sensitive people notice it.	Light smoke aloft from the Clackamas-drainage fires mixes down overnight and scours out with afternoon onshore flow.
2 in 1022%	One smoky day AQI 100-150 One day where the ridgeline across the highway goes flat grey, visibility a couple of miles, eyes and throat scratchy, everyone retreats indoors by mid-afternoon. The other two days noticeably better.	A short offshore or stagnant-southerly night drains Austin/Grasshopper smoke into the Sandy valley and it sits under an inversion until the next day's mixing.
2 in 1017%	Real smoke episode AQI 150+ Brown-orange daylight, the mountain gone entirely, headlights on at noon, smoke indoors through any open window, cancelled plans, people with asthma genuinely unwell.	A multi-day easterly or a new west-side ignition inside fifteen miles; smoke source upwind and no marine push to flush it.

Clear AQI 0-50

You can see the mountain. Nobody notices anything.

Hazy AQI 50-100

Visible haze, ridgelines soften, faint campfire smell.

Smoky AQI 100-150

Distinctly smoky, orange sun, eyes sting a little.

Bad AQI over 150

Mountain invisible. You smell it indoors.

Where the fires are

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, 40 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.

Day by day

Fri Aug 28

Hazy

likely 78 - could reach 155

30% chance of a smoky day

Sat Aug 29

Hazy

likely 82 - could reach 168

34% chance of a smoky day

Sun Aug 30

Hazy

likely 82 - could reach 175

34% chance of a smoky day

The specific odds

All three days clear11%

At least one smoky day (100+)46%

Two or more smoky days28%

At least one bad day (150+)22%

US-26 closed during the trip3%

Evacuation level at Welches6%

The one thing that would bring smoke here

Long-range wind signal unavailable this run.

When we'll actually know more

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.

Hover a dayto see the forecast we logged that morning and how much was known.

▲ Since 2026-08-10 the forecast has moved worse (+58 on the likely worst day) across 76 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

Why we think this

The mechanism that matters for this address is not the statewide acreage but whether there is an active smoke source upwind with a path into the Sandy River valley. Grasshopper is large (93,971 acres) but at bearing 090 and 17.4 miles it sits east of the crest, so it only reaches the house on an offshore/easterly pattern, which runs about 31% of member-days in this calendar window climatologically; Austin (12,888 acres, 18 mi S) and The Narrows (304 acres, 13.9 mi SSW, in the Clackamas drainage near 45.14N/-122.09W) are on the SAME side of the crest, so terrain does not shield the house from them and no wind reversal is required — only weak nocturnal drainage and an inversion. Against that, the default late-August pattern here is onshore marine flow that ventilates the valley every afternoon, which is why the climatological median daily max is 86 rather than 150, and why the dominant outcome is hazy-not-harmful. I did not apply a general bad-year multiplier on top of the season anomaly as instructed, but I also declined to lean on that 1.02 ratio as reassurance, because its 30-day window ends on 2026-10-25 and therefore measures post-season, rain-washed air rather than anything about the trip. The upper tail is widened for two reasons the base rate cannot see: the archive starts in 2022 and has never sampled a 2020-class event, and the remaining lead time in a PL5, 96%-drought, record-low-snowpack year was long enough for a brand-new fire to start closer to the house than any of these. Net: anchor 86, multiplier 1.12, worst-day p50 of 96 with a fat right tail to 190 at p90.

A normal late August here is Hazy - median AQI 86 across the last 4 years. On these exact dates: 2025: 112 · 2024: 72 · 2023: 76 · 2022: 78.

We are forecasting a worst day of 100, 14 points above that base rate. That departure rests entirely on the reasoning above; judge it for yourself.

What the bad version needs:
The Austin fire (12,888 acres, 18 mi S) and/or a new ignition in the Clackamas or Sandy drainage keeps an active smoke source on the WEST side of the crest, where terrain does not shield the house. → A thermal trough or weak offshore gradient sets up over the Cascades: night-time easterly/southerly drainage carries smoke down-valley into Welches and an inversion traps it below ridge top. → Afternoon onshore flow stays too weak to flush the valley, so the 24-hour average — not just a smoky hour — climbs past 150 and holds for a second day.
First visible signal: The Estacada and Sandy PurpleAir/AirNow sensors start the day already above 60 instead of in the teens — the overnight floor rising is the tell, visible on any phone air-quality app before the sky looks bad. - about 2 days ahead

Key drivers, and what would change our minds

Two fires on the same side of the Cascade crest as the house (Austin 12.9k acres at 18 mi S, The Narrows at 13.9 mi SSW) — no wind reversal needed for their smoke to reach Welches
The 94k-acre Grasshopper fire is east of the crest, so it depends on a ~31%-likely offshore pattern
All three fires were at 98% containment by mid-September, implying a shrinking source term through the back half of the season
Climatological dominance of onshore marine flow in late August (~69% of days) as the ventilation mechanism
Record drought, lowest-on-record April snowpack and PL5 resourcing raise the odds that a NEW ignition starts close and grows before initial attack contains it
Only four years of air-quality archive, excluding 2017/2018/2020/2021 — the upper tail is under-sampled, not measured

The Estacada or Sandy sensor on the AirNow app reading above 100 for a full day in the week before the trip
Watch Duty showing a new fire west of the crest within 20 miles of Welches
A Welches NWS forecast calling for east or southeast wind on two or more trip days
Containment on Austin dropping, or its acreage jumping, on InciWeb
The first real frontal rain crossing northwest Oregon before the trip — that would season-end this and push me to a clean GO
A Level 1 evacuation notice anywhere in the Hoodland corridor

Fires within 60 miles

13.9 mi	The Narrows SSW	304 acres · 98% contained
16.5 mi	Timber Lake/Ripplebrook Admin Rx - West SSW	size not yet reported
17.4 mi	Grasshopper E	93,971 acres · 98% contained
18.3 mi	Austin S	12,888 acres · 98% contained
20.3 mi	Austin Repair Pile Rx - West S	size not yet reported
23.0 mi	Goat Stew Rx - West S	size not yet reported
29.5 mi	Slow DXP/Lemiti Rx - West SSE	size not yet reported

The biggest hole in this forecast: 4 of the nearby fires (Timber Lake/Ripplebrook Admin Rx - West, Austin Repair Pile Rx - West, Goat Stew 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.

Pack this regardless

Two or three HEPA air purifiers sized for the main room and the bedrooms where kids sleep
A box of N95 or KN95 respirators — enough for twelve people for three days, not one each
Rescue inhalers and any asthma/allergy meds, carried not checked, for anyone who uses them
Eye drops and saline nasal spray
An indoor rainy-day plan: cards, board games, a projector or streaming setup
A cheap portable PM2.5 monitor so you can see indoor versus outdoor and know whether closing up is helping

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.

Watch list, and getting there

24-hour PM2.5 AQI at Estacada and Sandy, especially the overnight minimum - Overnight low above 60, or any 24-hour value above 100 two days running (https://fire.airnow.gov/ or the AirNow app)
Containment and acreage on Austin and The Narrows (the west-of-crest fires) - Containment falling, or acreage growing more than ~20% in a day (https://inciweb.wildfire.gov/ and https://www.nwccweb.us/)
Wind direction in the Government Camp / Welches forecast - East or southeast winds forecast for two or more consecutive days (https://forecast.weather.gov/MapClick.php?lat=45.3201&lon=-121.9561)
New ignitions within 30 miles - Any new fire west of the Cascade crest inside 20 miles of Welches (https://www.watchduty.org/ (set an alert on Welches))
Evacuation levels and US-26 status - Level 1 anywhere in the Hoodland corridor (https://www.tripcheck.com/ and Clackamas County Sheriff alerts)

Sandy	19.4 mi
Brightwood	15.5 mi
Welches	14.8 mi

Distance from each point on the drive in to the nearest fire. TripCheck is the authority on closures.

If we wanted cleaner air, where would we go?

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.

“Bad day / typical” is what the air actually did on Aug 26 – Sep 1 in 2022, 2023, 2024 and 2025 — 28 days per place. The first number is the bad day: one day in ten was worse than this. The second is the typical day, the middle of the range. We rank on the bad day rather than the typical one, because the bad day is what would spoil a weekend.

Both are converted onto the same scale as the “now” column, so every AQI figure in this table is comparable. That conversion matters more than it sounds: the model these come from runs about 2.5× high on the coast but close to true inland, so before correcting it the coast looked far worse than it is.

Place	Bad day / typical	Now	Official forecast	Next 5 days	Nearest fire
Astoria coast	19 / 16	20 Clear	Good	– steady	84 mi · High Lava
Long Beach, WA coast	19 / 17	20 Clear	Good	▲ worsening	97 mi · High Lava
Newport coast	25 / 21	52 Hazy	Good	– steady	101 mi · Austin
Welches / Mt Hood booked	30 / 22	38 Clear	Good	– steady	14 mi · The Narrows
Manzanita coast	30 / 28	24 Clear	—	– steady	87 mi · High Lava
Cannon Beach coast	31 / 27	24 Clear	—	– steady	88 mi · High Lava
Pacific City coast	32 / 29	24 Clear	—	▼ clearing	91 mi · The Narrows
Hood River east of crest	46 / 30	27 Clear	Good	▲ worsening	21 mi · Grasshopper
Silver Falls valley	50 / 37	51 Hazy	—	▼ clearing	31 mi · Austin
Portland valley	67 / 54	69 Hazy	Good	– steady	36 mi · High Lava
McMinnville valley	76 / 53	60 Hazy	Good	▼ clearing	54 mi · The Narrows
Bend east of crest	78 / 45	28 Clear	—	– steady	36 mi · Bench

What each column covers, and where it comes from

Field	Period it covers	What it is
Air right now	10/25/26 4:00 PDT	Nearest EPA/AirNow ground monitor to each place, within 45 miles airnow.gov
Official forecast	issued 10/25/26 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 2026-10-29	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, 2026-10-09 to 2026-10-22	Median of daily model-vs-monitor ratios — the bias differs by place, from 0.351 on the coast to 1.066 inland AirNow daily archive
Nearest fire	queried Oct 25 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.

How this is made, and what it cannot do

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 160, 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 355 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 US EPA AQI for PM2.5 as a 24-hour average quantity — specifically, for each of August 28, 29 and 30, 2026, the highest 24-hour-average AQI value that touches that calendar day at the house in Welches, Oregon (45.3201N, -121.9561W) — and then the single worst of those three days. All values are on the local monitor scale, i.e. what a phone air-quality app would display, with the model-to-monitor calibration already applied in the evidence pack and no further bias correction of my own. These are not hourly peaks and not a trip average.”

Updated daily at 5am. A convenience, not an authority -
if officials issue an evacuation order, follow it.