Fuels and Drought Outlook
Heavy rains have continued to spur the growth of seasonal grasses and a much heavier grass crop can be expected across most areas compared to the past 2-3 years. This is especially the case over the central coast which hasn’t seen a prior significant subsoil recharge since 2011. Further south, conditions are definitely drier, but rainfall has been frequent enough to keep grasses from curing on all but the most severe south aspects.
Due to the influence of above normal SST’s and a higher than usual amount of subtropical moisture availability, snow levels have been very high during many of the storms. The storms of early February brought rain even to elevations over 8,000 feet. These high elevation rains have resulted in Sierra snowpack survey numbers even lower than last year, even though precipitation amounts are over double of last season in Central California. Most stations in the snowpack survey conducted by the California Cooperative Snow Survey show current values are only in the teens as a percentage of average April 1st snowpack
These alarmingly low totals will mean California will likely enter a 4th summer of very low water levels in reservoirs. Extreme and exceptional drought (D3 and D4) drought will continue to cover wide swaths of the area. Meltout will occur several weeks early this year due to the poor snow cover and above normal temperatures expected.
Therefore, due to a heavier grass crop this year with the likelihood of warmer and drier than average weather this spring, large fire potential will likely climb to above normal levels by late May or June. There will be a much heavier amount of fuel loading of fine fuels compared to the past few years and there may be a spike in wildfire activity coincident with the curing of grasses in late April and May.
Later in the spring, expect higher than average large fire potential to spread into the higher elevations due to low levels of subsoil moisture. Nearly all fuel types from native brush and shrubs up to higher elevation timber have seen a tremendous amount of die-off due to the 3 years of ongoing drought. These areas comprised with a high amount of dead fuels will see rapid drying once seasonal rains end this spring.
The past few years have seen an above normal “monsoon season” over the Southwest. Although it is too soon to anticipate how much rainfall will occur this summer, early indications are for another year of above normal thunderstorm activity in the mountains.
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