Statewide Discussion: The updated Drought Monitor expresses a slight expansion of drought effects, but captures notable degradation with an 8% increase D3 (Extreme Drought) which now spans nearly one-third of Oklahoma. Regarding wildfire indices, drought is reflected in the criticality of the dryness in the dead fuel size classes, very dry upper-level soil moisture and near record setting Energy Release Component. While reinforcing rainfall is expected this afternoon through Monday in the Panhandle, northwestern and a few north-central counties, those areas where critical dryness resides are not likely to benefit from wetting rains. Reduced fire danger indices in the northwest/west will be welcomed, although persistent concern remains from southwestern Oklahoma into northeastern Oklahoma and points southeast.
Today: Fire activity from yesterday continues to be reported given some large fires occurring that were responded to by rural fire departments. Again today, the stronger winds will develop in the northwest and western counties where other fire weather elements are reduced while further east will again see very dry conditions lacking critical fire weather elements. Above-normal wildfire occurrence is expected to continue with initial attack remaining largely successful with low to moderate large fire potential.
- North-Central/Northeast Oklahoma: Temperature in the mid- to upper-70°s with relative humidity values 23-31% will yield fine-dead fuel moisture at 5%. South-southeast winds 10-17 mph with some gust above 20 mph will support grassland rates of spread 78-120 ft/min and flame lengths +/-13 ft. Higher rates of spread nearing 175 ft/min are possible in the heavier grass loading from Kay through Washington Counties. One mitigating factor may be presence of some sky cover late this afternoon limiting insolation and fuel temperature.
- Eastern Oklahoma: Highs 74°-77° under mostly clear skies and afternoon relative humidity values 22-25% will again yield very receptive carrier fuels at 4-5% fine-dead fuel moisture. Southeast winds sustained 6-13 mph will support head fire rates of spread in grass-dominated fuels at 68-90 ft/min and flame lengths 7-10 ft. Timber-litter will exhibit ROS nearer to 15-25 ft/min and FL +/-5 ft. Pine needle cast will support a bit more uppity fire behavior with regard to ROS and FL noting that torching, spotting and flare ups where jackpots of fuels exist should be anticipated.
- Western/Southwestern/Central Oklahoma: Highs will be in the 72°-76° range with afternoon relative humidity values above 35% (southwest) to around 25% (along/east of I-35) yielding fine-dead fuel moisture at 5-6%. South-southeast winds sustained 9-16 mph with some gusts topping 25 mph (especially southwest) will support moderate to rapid rates of fire spread. Range and grass fuels will support head fire ROS 74-119 ft/min and FL +/-9 ft. Mixed fuels will exhibit ROS +/-43 ft/min and average FL 8 ft. noting that problematic fire behavior is likely including torching, spotting and flare-ups where heavier fuel concentrations reside. Of note, recent fire activity has included torching hardwoods generating significant spotting potential.
- Oklahoma Panhandle/Far Northwest Counties: Higher humidity values and approaching rains will limit fuel receptiveness, although cumulative drying will prompt moderate rates of spread on any established wildfire today ahead of rainfall. Temperatures today will range from the mid-60°s in Cimarron County to 77° in Woods County with increasing sky cover and relative humidity values 55% (western Panhandle) to 31% (further east) limiting fine-dads fuel moisture from dipping below 6%. South winds will be stout again today sustained 19-23 mph with some gusts around 30 mph. Wildfires that become established will exhibit head fire rates of spread +/-130 ft/min, but again only if they become fully established. Probability if initial attack success is high with low large fire potential.
Saturday: Rainfall probability increases in the Panhandle overnight progressing into northwest Oklahoma while fire danger persists in the central and especially eastern regions. The highest fire danger indices will generally reside in the eastern 1/3rd of Oklahoma where temperature will register in the upper 70°’s with afternoon relative humidity values again around 25%. Easterly winds will be a bit less intense than Friday in this area sustained 4-11 mph. As such, rates of fire spread will be reduced to +/- 65 ft/min with 10ft. flame lengths. Potential for sporty, problematic fire behavior continues in the mixed (grass/brush) and timber fuels. Initial attack activity is expected to be successful.
Sunday: Again, the fire danger focus will be in the eastern 1/3rd of Oklahoma with a warming trend pushing temperatures around 80° coupled with afternoon relative humidity again +/-25% yielding receptive carrier fuels. Winds will become more southeasterly with similar windspeeds to Saturday sustained 4-11 mph. Grass-dominated fuels in the dry areas will generate head fire rates of spread +/-75 ft/min and initial attack activity remains largely successful outside of those fires occurring where normal firefighting tactics are limited due to access. Rain chances expand out of the Panhandle and far northwestern Oklahoma into the evening and overnight hours.
Near-Term: The rainy system parked over the Panhandle and northwestern counties will eject to the east on Monday bringing higher rain chances into northern and central Oklahoma. Unfortunately, outside of the Panhandle and Northwest Oklahoma, wetting amounts are unlikely as captured by the current 7-Day Quantitative Precipitation Forecast. Dry conditions will dominate the forecast into next week along and southeast of I-44 wherea noticeable uptick in wildfire activity has been observed, although critical fire weather in not anticipated at this time.
The seasonal temperature and precipitation outlooks were updated yesterday and do not bode well for wildfire potential heading into the dormant season, especially given the intensifying drought that continues to build in Oklahoma. Now, is the time for fire departments, agencies and emergency management organizations to emphasize prevention, preparedness and homeowner mitigation practices given the grim outlook for the dormant season.
Burn Bans: Refer to: https://ag.ok.gov/divisions/forestry-services/ for the most current burn ban information and links to specific burn ban proclamations.
