FogCast · Hoh Rain Forest, WA

Fog Forecast for Hoh Rain Forest

Know before you drive: FogCast checks the conditions that produce photogenic fog

Reading current conditions…
Current Conditions
Fog Potential:
Humidity
Wind
Temp
Dew Point Gap
🔒 App Exclusive
The full FogCast forecast is in the app.

Get more than a snapshot of current conditions. The LightCast app unlocks everything to plan ahead

  • 📈 Full FogCast score (0–100)
  • 📅 7-day fog outlook
  • 🌅 Best photography windows
  • 🔔 Push alerts when conditions improve
  • ⭐ Save favorite locations
Download LightCast on iOS
7-day free trial · $2.99/mo

Why fog is hard to predict

Humidity alone isn't enough. Wind alone isn't enough. Cloud cover alone isn't enough. Photogenic valley fog requires several conditions to line up at once, and most weather apps don't read them together.

Dew Point Depression
When air temperature and dew point converge below 2°C, the air is near saturation. This is the single strongest fog predictor and the first thing FogCast checks.
Wind Speed
Fog needs calm air. Below 5 km/h is ideal. Above 15 km/h, fog disperses before it can pool in the valley. A standard weather app won't flag this combination.
Overnight Sky Clarity
Clear overnight skies let the ground cool rapidly, pushing surface temperatures toward the dew point. Counterintuitively, clouds overnight suppress radiation fog.
Temperature Trend
FogCast reads the overnight temperature arc. If temps are converging toward the dew point hour by hour, fog probability increases significantly by pre-dawn.
Check today's FogCast

What the app shows you
FogCast score and forecast in LightCast app FogCast score and forecast in LightCast app

Full FogCast score, fog type, chase-or-skip verdict, and 10-day outlook — all in the app.
Get LightCast Suite on iOS

Get notified instead of checking every morning

Set a FogCast threshold once. The app will alert you when conditions at your saved locations look promising, so you're not manually checking at 4am.

Wake up only when conditions look promising
🚗 Avoid wasted drives when fog never forms
Save your favorite photography locations
🌫️ Never miss a rare dense fog event
LightCast
iOS App
LightCast Suite
5 Photography Forecasting Tools

Don't waste a sunrise drive. Check FogCast before you leave.

Download on the App Store
7-day free trial · $2.99/mo
Learn more about LightCast →

Fog photography at Hoh Rain Forest

The Hoh Rain Forest in Olympic National Park receives up to 4,300mm of precipitation annually, making it one of the wettest places in the contiguous United States and one of the only temperate rainforests in North America. The forest's massive Sitka spruce, western red cedar, and bigleaf maple trees are draped in thick moss and hang with club moss curtains that become ethereal in fog. Any moisture in the air intensifies the green luminosity of the moss and the mystery of the cathedral forest interior.

The Hall of Mosses — a short loop through ancient bigleaf maple hung with Club moss — is the most photographed spot in the Hoh and is most spectacular in fog and misty rain. The Hoh River Trail along the valley floor gives longer exposures to the old-growth forest in varying fog depths. The visitor center meadow provides open views toward the Olympic peaks, which are usually cloud-capped and dramatic. There is no bad season here, but autumn — September through November — brings deep morning mist into the valley floor combined with yellow maple leaves, making it the single most rewarding fog photography season.

Hoh Rain Forest fog is almost always present in some form due to the extreme moisture and minimal temperature range. True thick ground-level fog forms most reliably in autumn when overnight temperatures cool the valley floor while the surrounding forest holds warmth and moisture. A calm night following a day of rain is the most reliable fog setup — the saturated ground releases moisture into still, cooling air and produces a ground fog layer by pre-dawn that sits 1 to 2 meters above the moss-covered forest floor.



Frequently asked
Can I check FogCast on the website?
This page shows a preview of current conditions, including humidity, wind, temperature, and dew point. The full FogCast score, 7-day outlook, push notifications, and best shooting windows are available exclusively in the LightCast app for iOS.
Is FogCast free?
The current conditions preview on this page is free, no account needed. The full FogCast tool is in the LightCast Suite iOS app, which includes a 7-day free trial. After the trial it's $2.99/month, cancel anytime in the App Store.
Why use FogCast instead of checking humidity?
Humidity alone doesn't tell you whether photogenic fog is likely. High humidity with strong wind produces no fog at all. FogCast combines dew point depression, wind speed, overnight sky clarity, temperature trend, and visibility into a single score built specifically for fog photography planning.
What is FogCast's scoring scale?
FogCast scores fog conditions from 0 to 100. A score of 75 or above indicates dense fog is expected. 55 to 74 means fog is likely and worth chasing. 35 to 54 suggests patchy mist is possible. Below 35, conditions are unlikely to produce photogenic fog. The full score is available in the LightCast app.