The Sourdough Fire was reported on Saturday 29 July 2023. The fire is located in Ross Lake National Recreation Area within the North Cascades National Park Service Complex and is burning in very steep terrain. Please go to the Video Tab on this page to see our daily Operations Briefing.

Primary Fuel Model, Materials, or Hazards Involved (hazardous chemicals, fuel types, infectious agents, radiation, etc):
Timber (Litter and Understory)

Narrative:
Fuel Model Y. Timber with deep liter, duff and associated understory brushes and grass. ERC's 92nd percentile

Observed Fire Behavior or Significant Events for the Time Period Reported (describe fire behavior using accepted terminology. For non-fire incidents, describe significant events related to the materials or other causal agents):Active
 

Group Torching
Flanking
Backing
 

Narrative:
Roll out occurring, Group torching with short uphill runs. Active fire behavior as fire backs toward drainage bottom, then moves back uphill. Growth and future potential with terrain influenced spread and dry fuels. Extremely Steep and inaccessible terrain

48 hours: Thunderstorms expected to arrive Friday with the potential for gusty outflow winds and lightning.

12 hours: Fire activity expected to increase throughout the day as warm temps and low RH, along with northerly winds a concern. Single tree torching with spot fire development is likely.