Grotto Fire

Perimeter mapped August 21, 2026 at 2:40 PM MDT, 3,856 acres (mixed methods). Point of origin 46.256, -115.094.

Live radar at the fire Forecast for Pinesdale

Size

3,856 acres

Containment

20%

Discovered

July 29, 2026 at 5:42 PM MDT

Cause

Undetermined

Location

20 Miles E from Lowell, ID

County

Idaho County

State

Idaho

Protecting agency

USFS

Jurisdiction

USFS

Land ownership at origin

USFS

Personnel assigned

1

Incident management

Type 4 IC, Type 4 Incident

Primary fuel

Timber (Litter and Understory)

Estimated cost to date

$6,000

Incident type

Wildfire

Unique fire identifier

2026-IDNCF-000348

IRWIN identifier

687D3124-6031-4C95-B574-6AFB110FD389

Mapped area at the last perimeter of each day, from August 21, 2026 (907 acres) to September 3, 2026 (3,856 acres). The largest one-day growth was 2,014 acres, mapped August 28, 2026.

• Wind up to 5 mph from the northeast
• Relative humidity as low as 42%
• High of 69°F

National Weather Service hourly forecast for the fire’s point of origin, next 24 hours.

Full forecast for Pinesdale, MT

Red Flag Warnings and Fire Weather Watches covering the fire's point of origin.

No Red Flag Warning or Fire Weather Watch is in force at the fire.

NOAA’s Hazard Mapping System analysts have not drawn smoke over the fire’s origin today.

NOAA’s smoke model forecasts near-surface smoke at the origin peaking at 0.3 µg/m³ around Sun, 8:00 AM MDT over the next 48 hours.

Smoke and fire layers on the radar

• Pinesdale, MT42 miles east of the fire’s origin
• Hamilton, MT45 miles east of the fire’s origin
• Kamiah, ID45 miles west of the fire’s origin
• Stevensville, MT51 miles east of the fire’s origin
• Grangeville, ID54 miles southwest of the fire’s origin
• Orofino, ID57 miles west of the fire’s origin