Significant rains have fallen across portions of the Southern Plains recently. Widespread rainfall amounts from eastern New Mexico across northern Texas and southern Oklahoma total around 2-4 inches. Isolated locations have received around 6-8 inches, and most of this has just fallen in the past few days (image 1).
More rain is on the way, especially for eastern portions of Texas and the southern Mississippi Valley over the next couple of days as a plume of deep tropical moisture and the remnants of Hurricane Patricia become swept into the region ahead of an advancing trough of low pressure. Numerous flash flood watches and warnings have been posted for much of this area. Interestingly, parts of this same region, are still considered in D4 drought, due primarily to very dry conditions that have persisted since the summer months (image 2).
Drought reductions will very likely be in order with upcoming weekly issuances of the Drought Monitor.
Soil moisture across the region, per the 3-km SPoRT LIS has increased dramatically, especially the shallow layer soil moisture. I thought I’d take a moment to share a loop of 0-10 cm Relative Soil Moisture values during the past few days. These values go from as low as ~5% in the beginning of the image across a large swath of Texas to ~70-80%, especially in northern parts of Texas and around the DFW metro area. Further rains in the area of recently, nearly saturated soils will only increase the risk for runoff and the potential for further flooding. These data are being ported into some NWS offices to aid forecasters in situational awareness for the risk for flooding and for drought analysis. Little did some forecasters know that they would have the opportunity to utilize the data for both purposes in the same week! Having the data in AWIPS is just one advantage of the SPoRT LIS data. Other advantages are the spatial resolution (3 km) and the temporal latency (~2-8 hours). This relatively short latency over other legacy soil moisture data sets is possible due to the incorporation of MRMS precipitation data for forcing the model in the shorter term (~<4 days).
Of course, soil moisture will be slower to increase in deeper layers, as this recent depiction of 0-200 cm Relative Soil Moisture shows. Nevertheless, look for future increases in this deeper layer over the next couple of days.