The first significant cool front this fall is expected to push through Comal County and New Braunfels early Monday, ending more than a month of above-normal temperatures but not expected to bring measurable rain.
Highs in the upper 90s on Sunday will drop into the upper 70s by Monday afternoon. Winds will shift from southeast to north in the early hours Monday, gusting as high as 20 mph by afternoon. Rain chances are forecast at 30% Sunday night and 20% Monday morning.
“We have small chances of rain but not for any significant accumulations of rainfall,” said Brett Williams, meteorologist with the National Weather Service office at New Braunfels Regional Airport, said on Saturday. “I don’t see it putting any dent in the drought conditions we’ve had since early summer.”
Williams said the last measurable rains at the airport occurred on June 4 and June 17, each totaling around a half-inch. The last significant rain at the airport was 2.53 inches on May 3.
Monday’s cool front won’t last long, he said. High temperatures will rebound into the low 80s on Tuesday, upper 80s on Wednesday and reach close to 90 degrees ahead of a second front arriving late Thursday that will drop Friday’s highs into the mid-70s.
There’s not much of a rain chance with that front either, he said.
“It will be similar to the one we’ll have Sunday night into Monday,” Williams said. “There will be a significant drop in the temperatures, but not much rain, with a 30% percent chance of rain and thunderstorms on Thursday.”
The Keetch-Byram Drought Index (KBDI), used to determine forest fire potential based on daily water balances and soil moisture depletion, averaged 747 in Comal County on Saturday.
Every 100 points of the KBDI equals an inch of dry soil depth. Comal County Commissioners approved a ban on outdoor burning in unincorporated county areas on July 26 after the county’s KBDI average exceeded 500.
Under the restrictions no open flames are allowed outdoors – including trash burning, campfires and torches. Residents can barbeque on grills with lids that are set off the ground; welders should use spotters for outdoor work and keep water sources nearby.
Since 2.71 inches of rain fell at the airport in June, monthly totals amounted to 0.44 inches in July, 0.14 inches in August and 0.86 inches in September. After a trace of rain was recorded on Oct. 2, it rain deficit over the last three months is 6.22 inches – and climbing.
Williams couldn’t say when the next measurable rain might arrive.
“It’s been a while – and my lawn also agrees that it’s been a while,” he said.