AUSTIN (KXAN) – A wet week is in store for Central Texas with the potential for our longest-lasting rain event since October of last year.
Tropical moisture coming from the south, plus a trough of low pressure planting itself over Texas will provide the perfect recipe for daily showers, thunderstorms and downpours.
The majority of this week’s rainfall is likely to come today and Tuesday as all the ingredients come together to produce scattered to widespread showers and storms. Heavy downpours moving slowly over the same area could produce flooding issues, especially for low-lying areas.
There is still some disagreement among our computer models regarding rainfall amounts.
The European computer model (ECMWF) (both deterministic and ensembles) has been trending lower with rainfall amounts, generally 1-3 inches.
The American model (GFS) has consistently pointed toward several inches of rain across the entire area, but the numbers have trended down over the past couple of days, generally 2-4 inches.
The National Weather Service’s Weather Prediction Center, but these amounts don’t account for rainfall that’s already fallen today or the rain that will fall through early evening, which could range from 1-3″ in some places.
Our take? A widespread 2-3″ of rain seems like a good bet by the upcoming weekend with most of it coming today through Wednesday, but the tropical nature of these downpours could make for some much higher totals in localized areas.
Despite our ongoing drought, flash flooding will be a concern almost each day next week as tropical moisture will enhance rainfall rates across the area.
On top of that, our drier soil may actually cause more runoff than wetter soil would, especially earlier in the week.
The Weather Prediction Center has most of us at a “slight” (Level 2 out of 4) risk for Flash Flooding Monday, and areas near and east of I-35 are in that “slight” risk again on Tuesday.
On Sunday afternoon the National Weather Service issued a Flood Watch for most of Central Texas from Monday and they’ve not extended it into Wednesday.
Remember, if you come across a flooded street “turn around, don’t drown.”
Before it rains
Here are some way to prepare for the potential for heavy rain
While our severe weather risk is relatively low, wet microbursts will be possible with some of the stronger thunderstorms. Damaging winds would be our greatest severe weather risk with a very low hail and tornado threat most of the week. Flash flooding poses our greatest risk overall.
Wednesday, Thursday, Friday, NEXT weekend and beyond…
As the aforementioned “cold” front gradually pulls away, our rain and storm chances will gradually fade with it.
There is some distinct disagreement amongst some of our better computer models regarding how much and how widespread rain will be from the middle to end of the week. The American (GFS) computer model keeps us pretty wet Wednesday-Friday, but the European (ECMWF) computer model has been signaling the heavier rain mid-late week sliding southeast of us and exiting early.
We will continue to keep rain chances through the work week and into next weekend, but the confidence in widespread rain starts to drop after Wednesday.
Still, the long-term extended forecasts continue to point to wetter than normal weather to wrap-up August and to begin September.
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