Brazos Valley Burn Bans: The following counties are under a Burn Ban: Brazos, Burleson, Grimes, Houston, Lee, Leon, Madison, Milam, Robertson, San Jacinto, Trinity, Walker, Washington
A smokey haze blew into the Brazos Valley, from the east and southeast, around 2pm Thursday afternoon. Controlled burns and an atmospheric inversion caused a hazy end to the day.
After a morning of freezing temperatures and frost were found across the Brazos Valley, warm and moist south to southeast winds turned around for the area.
With the colder air mass being shoved back to the north and that warm, moist air starting to take over, an "inversion" occurred in the atmosphere over Texas. Essentially a cool and dry air mass being eroded away as a warm and moisture filled one started moving in.
When an inversion occurs, occasionally cloud cover will develop and stay locked into the area. Thursday's inversion kept anything from the lower levels of the atmosphere from mixing upward.
Controlled burns -- likely near Beaumont in Hardin County -- took place earlier today. With a general flow from the east / southeast -- around high pressure over the Eastern United States -- that smoke was able to move towards the direction of the Brazos Valley.
On a normal day, any smoke from a fire would mix out through the upper portions of the atmosphere. Thursday, that smoke was "trapped" below the inversion (mentioned above) which caused haze and a smokey smell settle into the area.
Reports of Haze were reported across the entire Brazos Valley Thursday afternoon -- starting in the eastern half of the area and eventually drifting into western counties.