Statewide Discussion: Wildfire activity across Oklahoma has been subdued through much of February with cold temperatures and some precipitation events although underlying dryness remains a concern as warmer conditions
have returned coupled with more fire conducive weather. Over half of the state is registering 61-97 days separated from a wetting event. A large portion of western Oklahoma failed to accumulate 0.10” of rainfall equivalent in the last
two weeks. Fire environment conditions will be supportive of prescribed fire activities early in the week, noting that a frontal passage on Wednesday will prompt a switch in wind direction and potential for gusty north winds emphasized in western Oklahoma, meriting attention to mop-up efforts. Initial attack activity is expected to increase along with low/moderate large fire potential (>300 Acres). Significant fire potential remains low.
- Oklahoma Panhandle: Strong drying conditions through the weekend (Rh values in the teens) have resulted in increased fuel receptiveness. Today – Marginal to moderate overnight moisture recovery will set the stage for an earlier onset of active burning conditions as temperature warms into the low- to mid-70°s under mostly clear skies with afternoon relative humidity values 15-22%. 1 Hr. fuels will tap 3% briefly in the western Panhandle while 4% observations are more likely east. Light northerly winds sustained 5-9 mph with limited gust potential will present head fire rates of spread 62-92 ft/min with flame lengths 7-10 ft offering very good probability of initial attack success. Tuesday – Moderate overnight moisture recovery is again expected ahead of temperature again warming into the mid-70°’s under clear skies with afternoon relative humidity values 16-21% yielding fine-dead fuel moisture at 4% for most locations. Light and variable winds become southerly in the afternoon remaining rather light for the area 6-11 mph (a bit higher in western Cimarron County). During peak burning conditions on established fires, rangeland fuels will support head fire rates of spread generally around 90 ft/min noting that areas with heavier fuel loading will likely express ROS +/-125 ft/min and FL 9-12 ft.
- Western Oklahoma: It is anticipated that prescribed fire activity will ramp up early in the week ahead of a frontal boundary on Wednesday coupled with an uptick in initial attack activity. Today – following a cool start and moderate overnight moisture recovery, temperature will warm into the 74° (north) to 79° (south) range under mostly-clear skies with afternoon relative humidity values 12-22% prompting intensified drying and yielding fine-dead fuel moisture at 3-4%. Light winds this morning will become southwesterly to variable in direction this afternoon sustained 4-9 mph limiting fire spread potential. Grass-dominated rangeland fuels will support head fire rates of spread generally +/-85 ft/min noting that heavier fuel loadings on far western Oklahoma may support ROS nearer to 100 ft/min and flame lengths 10-12 ft. Tuesday – Following moderate overnight moisture recovery, afternoon temperatures will again register in the mid-70°s under mostly clear skies with relative humidity values 21-28% yielding 1-Hr fuel moisture at 4-5%. Variable winds in the AM will become southeast sustained 7-12 mph gusting to 17 in the afternoon. Rangeland fuels will exhibit head fire rates of spread 80 120 ft/min with flame lengths +/-10 ft.
- Central Oklahoma: Initial attack will increase this week and scouting of engine access is merited given areas wet ground limiting rubber-tire vehicle access. Today – Good overnight, moisture recovery will stall development of active burning conditions until the afternoon, when drying conditions settle in. Temperature will warm into the 70-74° range under clearing skies with afternoon relative humidity values 21% (west) to 35% (east) yielding fine-dead fuel moisture at 5-6%. Southwest to west winds sustained 5-9 mph with limited gust potential will hold grassland rates of spread to under 110 ft/min and flame lengths +/- 10 ft. Very good overnight moisture recovery will again stall active burning conditions on Tuesday before temperatures again warm into the 70°s with afternoon relative humidity values 26-37% yielding 1-Hr fuel moisture at 6 7%. Light and variable winds in the AM will become southeasterly in the afternoon sustained 6-11 mph. Head fire ROS in grass-dominated fuels at +/- 95 ft/min and FL around 9 ft. should be anticipated during peak burning conditions.
- Eastern Oklahoma: Today – Good overnight moisture recovery and lingering scattered sky cover will serve to stall active burning conditions until later this afternoon. Temperature will warm into the mid-60°s to low-70°s with afternoon relative humidity values 30-41% and fine-dead fuel moisture at 7%. Southwest winds sustained 4-9 mph will limit fire spread potential overall. Grass-dominated fuels will support head fire rates of spread topping out around 100 ft/min with flame lengths 10-12 ft. while timber-litter will retain elevated moisture limiting fire behavior. Timber-litter will likely support max head fire ROS +/-18 ft/min and FL 4 ft. On Tuesday, active burning conditions will again be stalled with good overnight moisture recovery prior to temperature warming into the 70°s with afternoon relative humidity values 30-42% and 1-hr fuel moisture at 6-7%. Light and variable winds will remain rather light through the afternoon becoming southerly sustained 36 mph. Fire spread potential will be hampered by the low wind speeds facilitating very good initial attack success opportunity.
Outlook: A frontal boundary is expected to slide across Oklahoma on Wednesday. Temperatures will be just a bit cooler than Tuesday although north winds will increase, especially in the western one-third of the state where winds sustained around 20 mph and gusts near 30 mph will challenge control lines from fire activity on Monday and Tuesday. Rangeland fuels will support more rapid rates of spread nearer to 250 ft/min (2.8 mph) on fully established fires where continuous, heavy-load fuel is present. While large fire potential is in the mix, significant fire potential continues to remain low. Energy Release Component has remained below the 70th Percentile through February, although by Wednesday afternoon we are expecting to see those values creep into the 70th % range in southwestern Oklahoma. ERC values above the 70th %tile point to increasing resistance to control and longer duration of firefighting resources to fully contain wildfires.
Fire danger indices will continue to ratchet up each day through Friday ahead of the next chance of meaningful precipitation late in the weekend/early next week. Will this rainfall opportunity break the current stretch of dryness in the west remains in question. The Percent of Normal Rainfall since December 1, 2024 will require an extended period of wetting rainfall to sway the current building dryness on the landscape. The current U.S. Seasonal Drought Outlook points to ‘Drought Development Likely’ coupled with an increasing concern for significant fire potential later in March.
