Update from Jeff:
A few strong to severe thunderstorms will be possible this evening.
Strong winds of 30-40mph likely overnight into early Friday behind a cold front.
A strong storm system will move across Texas today and tonight. Warm sector air mass is firmly in place over SE TX with surface dewpoints into the low 70’s. Southerly low level winds will rapidly increase later this morning into the afternoon hours a low pressure develops over the southern plains. Instability slowly builds under the mid level capping inversion (a layer of warm air in the mid levels of the atmosphere). This capping should prevent little more than a few showers through the afternoon hours.
As the surface cold front begins to move eastward later this afternoon and evening and the mid levels begin to cool, the cap over the area weakens. Strong lift along the frontal boundary appears to be enough to break the cap between 500-700pm along the I-35 corridor with rapid development of strong or severe thunderstorms possible. These storms quickly form into a line and move into SE TX early this evening, but with the loss of surface heating, these storms begin to weaken as shown on several of the high resolution models. Best chances for any severe weather will be from Columbus to College Station and then along and north of HWY 105. Storms along I-10 west will likely weaken as the move eastward, while storms across the northern portions of SE TX may maintain their intensity as the cap is weakest in this area.
While all severe modes will be possible, very large hail and damaging winds will be the main threats. Again, the severe risk is strongly tied to the weakening of the mid level capping inversion, and should that fail to happen, only a thin line of showers would result.
There has been little change to the SPC severe weather outlook over the last 24 hours.
Behind the front and impressive low level WSW/W jet develops overnight with very strong winds likely across portions of SW TX into the I-35 corridor and then spreading eastward into SE TX. Winds of 30-40mph will be possible. Strong winds across portions of SW TX may loft significant amounts of dust that could be transported into SE TX Friday morning.
A significantly drier air mass will spread into the region on Friday with low humidity values and cooler temperatures.
Jeff Lindner
Director Hydrologic Operations Division/Meteorologist
Harris County Flood Control District
9900 Northwest Freeway | Houston, Texas 77092
346-286-4000 (main) | 346-286-4165 (direct) | 281-924-2091 (cell)
jeff.lindner@hcfcd.org | Twitter: @jefflindner1