It has been very wet across the southern United States over the past few days. Parts of south Texas have had over 15 inches of rain from a slow moving weather system. Normally it would take 3 or 4 months to receive that much rain! On Monday El Campo, Texas, had almost 5 inches in on day.
So how has South Texas managed to receive so much rain in such a short period of time? It is all to do with its location in proximity to the Gulf of Mexico and the position of weather fronts over the past few days. A weather front has been draped from central Texas to the south Mississippi. A moist flow of air off the fairly warm Gulf of Mexico has been interacting with the weather front to produce the torrential rain. Think of the weather front like a ski slope and as the moist air feeds in of the Gulf of Mexico it gets lift from the boundary and in turn condenses to form more clouds and rain. The front stays in the same place for several days and the moist flow continues from the Gulf of Mexico, so the rain continues to fall.
Flood warnings have been issued for much of south Texas because of the deluge, but things may not improve until this weather system moves east around midweek.
Heavy rain has also been a problem in other parts of the US. In Las Vegas, Nevada, 20mm of rain fell on Monday. This is double their normal amount for an entire month of 11mm. The weather system that brought the rain to Las Vegas is now on its way to bring rain and snow to the southern Rockies after that it’s on to, yes! Texas!
