Mt Hood · Aug 28-30 · -44 days out Updated Sun Oct 11, 5:00 AM · refreshes daily at 5am

Still on, but worth watching.

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

First, a flag the group needs: the trip dates in this request are August 28-30, which is about six weeks before today's date of October 11, so this is a hindcast, not a forecast, and no decision is still open. Reconstructing those dates from the evidence, two sizable fires were almost certainly still burning within twenty miles of the house that weekend - a very large one east of Mt Hood and a smaller one due south on the same side of the crest as the house - so the most likely worst day lands in the hazy-but-tolerable range near 60, well above the 18 that a normal late-August weekend here delivers.

The real uncertainty is transport: on a west-flow weekend the house stays clean in the teens, while any easterly or southerly push could have driven one day past 100, and I put that at about one chance in three.

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 Multorpor9 · Clear
Nearest fire outside 10 miles13.9 mi · The Narrows
Wind pushing smoke our wayno - SSE at 2 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.

4 in 1043%	Clear weekend AQI 0-50 Marine air or steady westerly flow; Mt Hood sharp and visible from the Welches meadow, blue sky, no smell of smoke, maybe a faint brown smudge far to the east in the afternoon.	nothing
3 in 1031%	Hazy but fine AQI 50-100 Milky white sky, the mountain soft-edged or lost behind haze, a faint campfire smell at dawn in the river valley that burns off by mid-morning; sunsets unusually orange. Kids and healthy adults fine outdoors, one or two sensitive people noticing it.	Move the long hike to the morning, keep windows shut overnight, run a box-fan filter in the sleeping rooms.
2 in 1016%	One smoky day AQI 100-150 One day where the ridge across the highway is a grey silhouette, visibility a couple of miles, smoke smell persistent all day, eyes and throat scratchy. The other two days noticeably better.	Indoor day for that one day - cards, the lodge, a drive west toward Sandy or Portland where the air is usually cleaner; anyone asthmatic stays inside with filtration.
1 in 1010%	Real smoke episode AQI 150+ Daylight orange-grey, ash flecks on the car, visibility under a mile, headlights on US-26 at midday, the house smelling of smoke even with everything closed. Everyone feels it, not just sensitive people.	Leave or never arrive - drive west out of the valley; the Sandy/Salmon river corridor traps smoke worse than the lowlands.

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: 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, 26 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

Clear

likely 42 - could reach 115

14% chance of a smoky day

Sat Aug 29

Clear

likely 45 - could reach 125

16% chance of a smoky day

Sun Aug 30

Clear

likely 44 - could reach 124

16% chance of a smoky day

The specific odds

All three days clear31%

At least one smoky day (100+)30%

Two or more smoky days14%

At least one bad day (150+)12%

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 (+16 on the likely worst day) across 62 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 12 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 controlling mechanism is transport, not fire existence: by late August 2026 there were two significant fires inside 20 miles, and the evidence shows them at only 98% containment as late as mid-September, which means neither was lined during the trip and both were still producing smoke. The Grasshopper fire's 93,971 acres sit 17.4 mi due east, which places them beyond Mt Hood and the crest - that smoke needs an easterly reversal to reach the house, and the climatological offshore rate for this window is 31% per day with strong autocorrelation, so roughly half of three-day weekends see at least one such day. Crucially, the Austin fire's 12,888 acres are 18.3 mi due south, on the same west slope as the house with no terrain barrier at all, so southerly flow or ordinary nocturnal drainage down the Salmon and Sandy river valleys can pool its smoke in the Welches basin overnight without any pattern reversal - the prompt's warning not to assume terrain shields the house applies directly here. Against that, the default late-August pattern is onshore westerly flow that flushes the corridor and sends both plumes away, which is why I keep a 28% clear branch rather than only fattening the tail. The 4-year climatology anchor of 18 with zero days over 100 is measured but structurally unrepresentative: it excludes 2017, 2018, 2020 and 2021, and more importantly none of those four years had a near-100,000-acre fire within 20 miles, so I multiply it up about 3x to a worst-day median near 60 while leaving a long upper tail to 155 at p90 for the overnight-inversion case.

A normal late August here is Clear - median AQI 18 across the last 4 years. On these exact dates: 2025: 23 · 2024: 15 · 2023: 16 · 2022: 16.

We are forecasting a worst day of 58, 40 points above that base rate. That departure rests entirely on the reasoning above; judge it for yourself.

What the bad version needs:
The Grasshopper fire (93,971 acres, 17.4 mi due E) and the Austin fire (12,888 acres, 18.3 mi S) are still actively producing smoke in late August - both were only 98% contained as of mid-September figures, so neither was lined during the trip window, and fuels were at record dryness with firefighting resources at national PL 5. → A thermal trough or building interior high sets up offshore/easterly gradient flow across the Cascade crest (31% of member-days climatologically in this calendar window, and no ensemble forecast was available to argue that rate down), pushing the Grasshopper plume over the crest and down the west slope onto the house; OR - the path that needs no crest reversal at all - southerly flow or nocturnal cold-air drainage carries Austin fire smoke north down the Salmon/Sandy river valley and pools it in the Welches basin overnight. → An overnight inversion in the river valley traps that smoke near the floor through dawn and mid-morning, so the 24-hour average stacks up well above the afternoon-only values a visitor would guess, and the daily AQI lands 100-180.
First visible signal: The Government Camp / Multorpor PM2.5 reading on the AirNow app or PurpleAir map climbing out of the single digits into the 40s-60s, especially if the overnight and early-morning hours are the high ones rather than the afternoon; alongside an NWS Portland forecast switching the Mt Hood zone wind to east or southeast for consecutive days. - about 2 days ahead

Key drivers, and what would change our minds

The Austin fire (12,888 acres) is 18.3 mi due south on the house's own side of the crest - no terrain shield, and nocturnal valley drainage is a transport path that needs no wind reversal
The Grasshopper fire (93,971 acres) is 17.4 mi east, behind Mt Hood, so its much larger smoke load is gated on easterly flow at a ~31% climatological daily rate
Both large fires were still only 98% contained as of mid-September figures, so they were almost certainly uncontained and producing smoke on the trip dates
The east_wind_outlook ensemble field is null - the departure-from-climatology signal the method relies on does not exist here, so I fall back to the 31% base rate rather than claiming evidence either way
The climatology anchor of 18 comes from a 4-year archive with no nearby large fire and no catastrophic year, so its zero-percent-over-100 exceedance rate understates this particular window
Welches sits in a river valley that traps and holds smoke overnight, so 24-hour averages can run well above what an afternoon visit would suggest

Pulling the AirNow historical record for Government Camp on August 28-30, 2026 - that single lookup replaces this entire distribution with the answer
An InciWeb or NWCC sit report showing Grasshopper and Austin were already largely contained before August 28, which would pull my worst-day median back toward the climatological 18-25
Observed Government Camp winds running west or northwest all three days, which would make the clear branch the one that happened
Evidence of a third fire igniting west of the Cascade crest between mid-August and the trip, closer than 18 miles, which would push me toward the 150+ scenario
A smoke-advisory or air-quality-alert archive showing Clackamas County under an advisory on those dates, which any non-expert can check and which would confirm a day over 100
Photos from the group or from the Mt Hood/Timberline webcam archive on those dates showing whether the mountain was visible

Fires within 60 miles

12.9 mi	Kleinsmith W	size not yet reported
13.9 mi	The Narrows SSW	304 acres · 98% contained
17.4 mi	Grasshopper E	93,971 acres · 98% contained
18.3 mi	Austin S	12,888 acres · 98% contained
37.0 mi	High Lava N	2,899 acres · 95% contained

The biggest hole in this forecast: 1 of the nearby fires (Kleinsmith) 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 N95 or KN95 respirators per person - the cloth and surgical kind do nothing for PM2.5
A box fan plus two 20x20 MERV-13 furnace filters and duct tape - a $40 DIY Corsi-Rosenthal filter will hold one bedroom clean even on a 150 day
Inhalers, allergy and asthma medication for anyone who uses them, plus spares, since the nearest pharmacy is a drive
An offline-capable AQI app with the Government Camp/Multorpor station saved, and a downloaded map - cell coverage in the Welches corridor is patchy
A rainy/smoky-day plan: cards, board games, a couple of movies downloaded, since the fallback to 'we'll just hike' is exactly what smoke takes away
Enough food and water to skip one grocery run, so a bad-air day does not force anyone outdoors

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

What the Government Camp / Multorpor monitor actually recorded on August 28-30, 2026 - this is a lookup now, not a forecast - Any 24-hour PM2.5 AQI above 100 on one of those three dates means the smoky-day branch above verified; all three under 50 means the clear branch did (https://www.airnow.gov/ (Historical Air Quality / AQI data archive) or Oregon DEQ's Air Quality Monitoring data portal)
Grasshopper and Austin fire daily situation reports covering August 28-30 - acreage and containment on those specific dates, which the evidence pack only gives as of mid-September - Containment below ~40% with active growth on those dates would justify shifting probability mass toward the 150+ scenario (https://inciweb.wildfire.gov/ and the Northwest Interagency Coordination Center daily sit report archive)
Observed surface wind direction at Government Camp for August 28-30 - Sustained east or southeast component on any of the three days is the transport mechanism the bad path depends on (NWS Portland observation archive / MesoWest station TS021 or GCRO3)
If a future trip to this house is being planned, the forward-looking version of the east-wind ensemble that came back null here - Member-day offshore fraction running well below the 31% climatological rate is real evidence against the smoke path; well above it is evidence for (NWS Portland forecast discussion plus the ECMWF/GEFS offshore-gradient products)

Sandy	5.2 mi
Brightwood	5.2 mi
Welches	11.3 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
Welches / Mt Hood booked	20 / 15	8 Clear	Good	▲ worsening	14 mi · The Narrows
Newport coast	20 / 17	16 Clear	Good	– steady	101 mi · Austin
Astoria coast	25 / 22	13 Clear	Good	▲ worsening	84 mi · High Lava
Long Beach, WA coast	25 / 22	13 Clear	Good	▲ worsening	97 mi · High Lava
Manzanita coast	26 / 24	54 Hazy	—	– steady	87 mi · High Lava
Cannon Beach coast	28 / 24	54 Hazy	—	▲ worsening	88 mi · High Lava
Pacific City coast	29 / 26	54 Hazy	—	– steady	91 mi · The Narrows
Hood River east of crest	40 / 26	21 Clear	Good	▲ worsening	21 mi · Grasshopper
McMinnville valley	45 / 32	52 Hazy	Good	– steady	54 mi · The Narrows
Portland valley	46 / 37	56 Hazy	Good	– steady	36 mi · High Lava
Silver Falls valley	49 / 36	33 Clear	—	– steady	31 mi · Austin
Bend east of crest	56 / 33	60 Hazy	—	– steady	35 mi · Crosswhite

What each column covers, and where it comes from

Field	Period it covers	What it is
Air right now	10/11/26 4:00 PDT	Nearest EPA/AirNow ground monitor to each place, within 45 miles airnow.gov
Official forecast	issued 10/11/26 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 2026-10-15	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, 2026-09-24 to 2026-10-07	Median of daily model-vs-monitor ratios — the bias differs by place, from 0.37 on the coast to 0.694 inland AirNow daily archive
Nearest fire	queried Oct 11 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 (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 33, 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 285 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 computed as a 24-hour average concentration - specifically, for each of August 28, 29 and 30, 2026, the highest 24-hour-average AQI value touching that calendar day at the house in Mt Hood Village / Welches (45.3201, -121.9561), on the local monitor scale that a phone app displays (already calibrated from the raw model scale by the factor of 0.3 in the evidence pack, with no further bias correction applied by me), and then the single worst of those three daily values - not the three-day mean.”

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