The main threats with this system will be wind and hail and a low risk of tornadoes. The best chance of severe weather, at least as of this entry, is in central and northeast Texas near the Ark-La-Tex.
The Storm Prediction Center in Norman, Oklahoma has placed much of southeast Texas in a slight risk to as high as "enhanced" for the northern counties of the Houston viewing area. This represents a severity of 3 out of 5 -- so mid way.
The National Weather Service is urging all residents, mainly those north of I-10 to stay vigilant: "There is still a great bit of uncertainty how this weather event will unfold so keep up with the forecasts. The cold front will still trigger a line of showers and thunderstorms Saturday night and CIPS page showed between a half inch and one inch of rain with past events. Most of the area should receive some rain with the heavier totals to the north."
As I explained in a blog earlier this week found HERE, the only thing that can go wrong is the pesky cap and whether or not it'll break allowing the for the development of strong thunderstorms. See the blog for more information on what a cap is.
"So what could go wrong? Forecast soundings show a very strong capping inversion that just vanishes as a cold front and upper level dynamics approach. Not sure the cap will erode as the models suggest, especially over the southern half of the region. Took a look back at the CIPS analog page and previous events with this type of weather pattern only showed a few severe weather reports over the extreme northern parts of the southeast Texas," said the NWS.
Determining whether the layer of warm air in the atmosphere (the cap) will erode or not is proving to be challenging. Therefore we'll have to watch this event closely as it unfolds.
Here's what you need to know:
All of southeast Texas needs to keep an eye out for the possibility of strong to severe thunderstorms. However the main emphasis appears to be on the northern counties, i.e., Montgomery, Grimes, Walker, San Jacinto, Trinity, Madison and Houston counties. Strong to severe storms can't be ruled out in the southern counties either.
Current indications are that the front should approach Houston between midnight (far northern counties) and 5 a.m. (far southeastern counties/coast). The line of storms should cross downtown Houston around 3 a.m.
At this time the main threats appear to be gusty winds between 30 and 50 mph and small hail. While any severe storm can and often do produce tornadoes, the threat across southeast Texas in the immediate Houston area appears to be low. The tornado threat will be more north and east of the area -- perhaps into eastern and northeastern Texas.
Flooding will not be an issue with this system as it is expected to move through fairly rapidly. Only between a half inch to one inch of rainfall is expected. We can't totally rule out an isolated rain total of two or three inches but that still won't be enough to impact bayous or surface streets.
© 2017 KHOU-TV
Source : http://www.khou.com/news/local/severe-weather-to-threaten-houston-area-early-sunday/434910048