Moderate to severe drought has plagued the Coastal Bend for months, and lake levels are at an all-time low. Now, a major storm system will bring multiple inches of rainfall to the region. How beneficial will this wet-weather event be for our watershed? How much rain will it take for substantial improvements to our lakes, our drought conditions and our front yards?
Since last fall, conditions supporting meaningful rainfall have been nearly absent. Upper level high pressure has kept the atmosphere dry and stable, so any disturbances have produced little to no useful precipitation. Now we are entering into what is climatologically an active rainy season, and the ongoing wet-weather event is classic wet-weather scenario. An upper-level disturbance associated with the sub-tropical jet stream over the Eastern North Pacific is bringing moisture and instability, and also will draw in low-level moisture from the Gulf. The result will be deep-layer moisture, and coupled with instability from the upper-level storm, strong thunderstorms will bring periods of heavy rainfall through the end of the work week.
Rainfall estimates from short- and medium-range models suggest between 4 and 8 inches of total precipitation. While heaviest rain should be near the coast, where the atmosphere will be most unstable, beneficial rain also will fall in the Nueces River watershed.
Unfortunately, because of hard-packed and very dry soils, flash flooding is likely near coastal areas. It is important to note that, depending upon your soil type, rainfall could be largely absorbed or run off quickly. Clay soils tend to cause quick runoff, while sandy soils tend to absorb the moisture more readily. Urban and small stream flooding is likely with this event, so be extremely careful. Upstream in the watershed, much of the rain will soak into the ground before reaching our lakes. Still, anything is a good start.
And, a good start is what we need and what we are getting. Next week, more rain is expected. Hopefully, repeated rainfall events will provide ample runoff into our parched lakes.