Mt Hood · Aug 28-30 · 5 days out Updated Sun Aug 23, 8:51 AM · refreshes daily at 5am

Still on, but worth watching.

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

The one large fire near the house is on the far side of Mt Hood, is three-quarters contained, and the east winds that would carry its smoke over the crest to you are almost entirely absent from the forecast models for your dates. The monitor eight miles from the house reads 22 right now, which is clean, and the most likely worst day of your weekend is around 30 — a little haze on the ridgelines at most.

The real thing to watch is two small, uncontained fires about thirteen to nineteen miles south of the house on your side of the mountains; if one of those makes a big run this week you could get a single hazy-to-smoky day, and that's roughly a one-in-ten shot.

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 26
What would change this
  • Evacuation zone at the housenone
  • US-26 open, Portland to Welchesopen
  • Air at Multorpor22 · Clear
  • Nearest fire outside 10 miles12.5 mi · Mitchell
  • Wind pushing smoke our wayno - NW 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.

6 in 1061%Clear weekend AQI 0-50
Blue sky, maybe a milky band over the ridges in the morning that burns off; you can see Mt Hood clearly; nobody's eyes or throat notice anything.
nothing
3 in 1028%Hazy but fine AQI 50-100
A visible tan layer in the valley at sunrise, the mountain looks flat and washed out, and you can faintly smell campfire outside. Hiking and river time are still fine; sensitive people (asthma, the older folks, little kids) might want an easier afternoon.
Do the hike in the morning before the afternoon smoke drifts in, close the house windows overnight, run the box fan or purifier indoors.
1 in 107%One smoky day AQI 100-150
Grey-orange light all day, the ridge across the highway is a silhouette, smoke smell indoors, and phones showing 'Unhealthy for Sensitive Groups.' One day of the three, most likely tied to a big afternoon fire run to the south.
Move that day indoors — cards, board games, a drive west to Sandy or Portland where the air is usually cleaner. Sensitive people mask outdoors. Trip still worth taking.
0 in 104%Real smoke episode AQI 150+
You can't see the far side of the golf course, the sun is a red disc, everyone's throat is scratchy within an hour outside, and there may be fire-agency notices for the Zigzag/Welches area.
Cut the trip to one night or reschedule; if there's an evacuation notice, leave west on US-26 early rather than waiting.
Clear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendClear weekendHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineHazy but fineOne smoky dayOne smoky dayOne smoky dayOne smoky dayOne smoky dayOne smoky dayOne smoky dayReal smoke episodeReal smoke episodeReal smoke episodeReal smoke episode
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.

SandyBrightwoodWelchesGovernment Campan east wind would carry smoke from here10 mi20 miThe houseGrasshopper93,562 acres · 17.4 miAustin5,295 acres · 18.6 miThe Narrows13.9 miMitchell12.5 miSweetwater19.3 mifire perimetersmall fire, size knownlocated, size not reported10 milesEverything within 60 milesGrasshopperBenchAustinTen MileBeachcombHigh LavaThe NarrowsMitchellSweetwaterWest 80579 Ten Mile
SandyBrightwoodWelchesGovernment Campan east wind would carry smoke from here20 mi40 miThe houseGrasshopper93,562 acres · 17.4 miBench67,071 acres · 45.5 miAustin5,295 acres · 18.6 miBeachcomb2,346 acres · 49.5 miThe Narrows13.9 miMitchell12.5 miSweetwater19.3 mifire perimetersmall fire, size knownlocated, size not reported10 miles

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 (1,717 acres, 37.2 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 Aug 21 · Austin Aug 22 · The Narrows Aug 22 · Mitchell Aug 16. The oldest is Mitchell, 6 days behind. Acreage and containment are refreshed far more often than the outlines are re-flown — those figures were last updated Aug 22, 11:05 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 28 - could reach 74
5% chance of a smoky day
Sat Aug 29
Clear
likely 29 - could reach 80
6% chance of a smoky day
Sun Aug 30
Clear
likely 30 - could reach 88
7% chance of a smoky day

The specific odds

All three days clear58%
At least one smoky day (100+)12%
Two or more smoky days5%
At least one bad day (150+)5%
US-26 closed during the trip2%
Evacuation level at Welches5%

The one thing that would bring smoke here

1%of 156 ensemble member-days show the east wind that would bring smoke
vs 31% in a normal year — 30 points below normal
By trip day 08/28: 0% · 08/29: 0% · 08/30: 2%
By model gem global 21 members → 2% · gfs05 31 members → 0%
Base rate by year 2025: 22% · 2024: 44% · 2023: 44% · 2022: 22% · 2021: 22% (45 days, trip dates +/-3 days)

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.

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.

Sun Aug 23Mon Aug 24Tue Aug 25Wed Aug 26Thu Aug 27Fri Aug 28Sat Aug 29Sun Aug 30Fire size & containmentAug 23 - todayAug 30 - trip ends
Hover a dayto see the forecast we logged that morning and how much was known.

= Since 2026-08-10 the forecast has moved steady (-4 on the likely worst day) across 14 daily updates. Shading above shows source coverage, not this movement - hover a past day to see what we said that morning.

nowFire size & containment
how big the fires are and whether they are being held
nowLong-range ensembles (GEFS 0.5 + GEM)
wind direction, 52 members · reaches 32 days out
nowECMWF ensemble (51 members)
wind direction, the sharpest ensemble · reaches 13 days out
nowDeterministic weather (16-day)
day-by-day wind and temperature · reaches 15 days out
nowAir-quality / smoke model (CAMS)
actual AQI at the house · reaches 6 days out

Why we think this

The dominant smoke source in this neighborhood, the 93,562-acre Grasshopper fire, is 17 miles due east with Mt Hood between it and the house, and it is 76% contained and past its growth phase; delivering its smoke to Welches requires easterly/offshore flow, and the 156-member ensemble puts that at 1% of member-days against a 31% climatological rate for the same calendar window — a 30-point negative departure that is real evidence against the bad case, not just a restatement of a prior. What the ensemble does not cover is the local transport that is actually driving this year's elevated readings: the Austin fire (5,295 acres, 0% contained, 18.6 miles south) and The Narrows (223 acres, 0% contained, 13.9 miles south-southwest) are on the WEST side of the crest with no terrain shield, and with light southerly flow plus nightly down-valley drainage into the Sandy and Salmon River valleys, their smoke can pool at the house overnight and hold through the morning — which is exactly the mechanism that turns an afternoon whiff into an elevated 24-hour average. That mechanism is already priced in: the last 30 days at this location averaged a daily max of 21 against a typical 10, and with those same fires burning and the wind currently blowing from fire toward house, the monitor still reads 22. So I anchor on the 12 climatological median, apply 2.4x for the measured season anomaly plus the worst-of-three-days effect, and land at a worst-day median near 29 — clearly hazier than a normal late August, clearly not a trip-killer.

A normal late August here is Clear - median AQI 12 across the last 4 years. On these exact dates: 2025: 16 · 2024: 10 · 2023: 11 · 2022: 11.

We are forecasting a worst day of 38, 26 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 (5,295 acres, 0% contained, 18.6 mi south) or The Narrows (223 acres, 0% contained, 13.9 mi south-southwest) — both on the house's side of the Cascade crest, not shielded by Mt Hood — makes a major afternoon run in fully cured fuels while initial-attack crews are stretched thin at national Preparedness Level 5. → Light southerly synoptic flow, which the models already show for the weekend, carries the plume 13-19 miles straight up the Salmon and Sandy River valleys toward Welches. → Overnight down-valley drainage and a morning inversion pool that smoke in the valley floor where the house sits and hold it past midday, dragging the 24-hour average — not just an afternoon spike — above 100 for one, possibly two days.
First visible signal: The Austin or Narrows acreage jumping sharply in the daily InciWeb update, and the Multorpor/Government Camp monitor on the AirNow or PurpleAir app reading above 60 in the MORNING (a morning number that high means smoke is sitting in the valley, not just passing overhead). - about 2 days ahead
Key drivers, and what would change our minds
  • The only large fire nearby (Grasshopper, 93,562 ac) is east of the Mt Hood crest and 76% contained — it needs east wind to reach the house
  • Ensemble easterly-flow frequency for the trip dates is 1% of member-days vs 31% climatologically — a 30-point negative departure against the bad case
  • Two uncontained fires (Austin 5,295 ac, The Narrows 223 ac) sit 13-19 miles SOUTH, on the house's side of the crest with no terrain shield — this is the actual risk, not Grasshopper
  • Current observed AQI at Multorpor is 22 with wind already blowing from the fires toward the house
  • Measured local season anomaly is 2.0x normal — real but modest, and it already reflects these fires burning
  • Record Oregon fire season, 96% drought, cured fuels, and national Preparedness Level 5 mean a new close-in ignition in the next five days is more likely than usual and would be slower to contain
  • The AirNow monitor at Multorpor/Government Camp reading above 60 in the MORNING on any day before you leave
  • The Austin fire jumping past roughly 15,000 acres, or a new named fire appearing within 20 miles of Welches
  • An east-wind or Red Flag Warning appearing in the NWS Portland forecast for the Cascade foothills for Aug 28-30
  • Any Zonehaven evacuation zone covering Welches, Wemme, Brightwood or Zigzag going Level 1 or higher
  • Photos or webcams from Government Camp or Timberline showing the valley socked in rather than clear
  • A fire-related closure showing up on TripCheck for US-26 anywhere between Sandy and Government Camp

Fires within 60 miles

12.5 miMitchell S16 acres
13.9 miThe Narrows SSW223 acres · 0% contained
17.4 miGrasshopper E93,562 acres · 76% contained
18.6 miAustin S5,295 acres · 0% contained
19.3 miSweetwater Wsize not yet reported
37.2 miHigh Lava N1,717 acres · 19% contained
41.7 miWest 8 ENEsize not yet reported

The biggest hole in this forecast: 2 of the nearby fires (Sweetwater, West 8) have no size reported yet. Whether those are 300-acre creepers or 20,000-acre runners is most of the answer.

Pack this regardless

  • One or two HEPA air purifiers, or a box fan plus a 20x20 MERV-13 furnace filter taped to it (about $30 total, cleans a room in an hour)
  • A handful of N95 or KN95 masks — a dozen, not three; cloth and surgical masks do nothing for smoke
  • Inhalers and allergy meds for anyone who uses them, plus a spare
  • Eye drops — smoke irritation shows up in eyes before lungs for most people
  • A rain-or-shine indoor plan: board games, cards, a couple of movies downloaded, since cell and streaming at Mt Hood Village can be thin
  • Full gas tank and a printed or offline map of the US-26 route west to Sandy, in case you need to leave in a hurry with the cell network congested

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

  • Live PM2.5 at the Multorpor / Government Camp monitor, 8.7 miles from the house - Any morning reading above 60, or any reading above 100 at all, in the three days before you leave (fire.airnow.gov or the AirNow app)
  • Austin fire and The Narrows fire acreage and containment (both currently 0% contained, both SOUTH of the house on your side of the mountains) - Austin past 15,000 acres, or either fire still at 0% containment on Aug 27 with growth reported (inciweb.wildfire.gov and nwccweb.us daily situation report)
  • Evacuation zones for Clackamas County and the Hoodland corridor - Any zone covering Welches, Wemme, Brightwood or Zigzag turning Level 1 (Be Ready) or higher (community.zonehaven.com (search Welches, OR))
  • NWS Portland point forecast for Welches, specifically wind direction - Sustained east or southeast wind in the forecast for the trip days, or a Red Flag Warning for east winds in the Cascade foothills (weather.gov, click the map at Welches)
  • US-26 road status between Sandy and Government Camp - Any fire-related closure or pilot-car restriction on that stretch (tripcheck.com)
Sandy5.7 mi
Brightwood10.9 mi
Welches14.3 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.
PlaceBad day / typicalNow Official forecastNext 5 daysNearest fire
Newport coast18 / 158 ClearGood▲ worsening102 mi · The Narrows
Cannon Beach coast22 / 1911 ClearGood▲ worsening88 mi · High Lava
Hood River east of crest22 / 1516 ClearModerate▲ worsening21 mi · Grasshopper
Manzanita coast24 / 2211 ClearGood▲ worsening87 mi · High Lava
Pacific City coast24 / 2111 ClearGood▲ worsening91 mi · The Narrows
Astoria coast24 / 2114 ClearGood▲ worsening84 mi · High Lava
Long Beach, WA coast27 / 2414 ClearGood▲ worsening97 mi · High Lava
Welches / Mt Hood booked29 / 2110 ClearModerate▲ worsening14 mi · The Narrows
Silver Falls valley50 / 3710 ClearGood▲ worsening33 mi · The Narrows
Portland valley54 / 4411 ClearGood▲ worsening36 mi · High Lava
McMinnville valley56 / 409 ClearGood▲ worsening54 mi · The Narrows
Bend east of crest123 / 7216 ClearModerate▲ worsening22 mi · Akawa Butte
What each column covers, and where it comes from
FieldPeriod it coversWhat it is
Air right now08/23/26 8:00 PDTNearest EPA/AirNow ground monitor to each place, within 45 miles
airnow.gov
Official forecastissued 08/23/26 by Oregon Dept. of Environmental QualityNext published outlook for that reporting area — a human forecaster's call
Oregon DEQ via AirNow
Next 5 daystoday's model run, covering 2026-08-27Direction only. Copernicus CAMS global air-quality model
open-meteo.com
Bad day / typicalAug 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 conversionmedian of 14 daily model-vs-monitor pairs, 2026-08-08 to 2026-08-21Median of daily model-vs-monitor ratios — the bias differs by place, from 0.342 on the coast to 1.091 inland
AirNow daily archive
Nearest firequeried Aug 23 8:52 AMPerimeter 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 22, 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 40 scored forecast-days, the air-quality model beat both simple baselines at 4 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'm forecasting the US AQI for PM2.5 as a 24-hour average — the highest 24-hour-average value touching each calendar day at the Welches house — reported on the local monitor scale, meaning the number a phone app would show from the AirNow station at Multorpor 8.7 miles away, not a raw model value and with no further bias correction applied by me. The headline number is the worst single day of the three, Aug 28-30, not the average across them.”

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