Two severe weather threats: today, tomorrow night
A dynamic storm system will bring two threats for severe weather this week—today and tomorrow night.
Today and Tonight: With highs returning to the upper 70s, expect increasing clouds today with a line of showers and thunderstorms pushing in later this afternoon. A few storms could be strong with gusty wind and an isolated tornado is even possible. Our area has not dealt with high impact weather since the flood, so please make an effort to stay in touch with the forecast today. Storms may or may not become severe, we hope they don’t, but the threat exists and being prepared saves lives. The Storm Prediction Center (SPC) has placed much of the Baton Rouge area in a “slight risk” for severe weather, essentially 2 out of 5 on the scale. Additionally, a*wind advisory* is in place through 6pm with southerly breezes of 15-20mph and potentially higher gusts. Overnight, showers will end from west to east with lows staying near 60 degrees.
Up Next: After a brief break Tuesday, we could see a second wave, perhaps an even higher chance of severe storms late Tuesday Night and Early Wednesday Morning. Once again, damaging wind and an isolated tornado would be the main threats along a squall line. Behind the front bringing these storms, clear skies and much cooler temperatures are anticipated for the end of the week.
As a reminder, for the most immediate weather updates in Baton Rouge area, follow WBRZ Weather on Facebook and Twitter and take our live coverage with you on the WBRZ Weather app should it be necessary. 'Tis the season for severe weather, so stay in touch as each event is different.
The Tropics: The tropics are quiet and no development is expected this week.
Forecast Discussion: A shortwave trough will dig into a longwave trough over the Great Plains today. As this occurs, a strong jet streak will move from Texas to Tennessee leaving the forecast area in the favorable right rear quadrant. The close proximity of the jet will cause mid level and low flow to increase over Lower Mississippi Valley through morning. Winds will also be gusty at the surface, blowing out of the south at 20-30mph, veering with height as the upper energy approaches. According to the GFS Model, 0-3km helicity showed 225 to 300ms across the south half of the forecast area and 300 to 450ms across East Central Louisiana and Southern/SW Mississippi Monday Afternoon. However, a very short period of warm air advection will only yield marginal instability and cape values of 100 to 400J/kg. Therefore, discrete cell development will be limited and frontal lift will be needed to produce storms with embedded, potentially rotating, storms Monday Afternoon through Evening. Strong, damaging winds will be the other possible mode of severe weather. Action will temporarily settle Monday Night through Tuesday. Another disturbance on the back side of the longwave trough will maintain the strong jet stream from East Texas to the Great Lakes region Tuesday Night. Another, stronger surface front will push through the forecast area Early Wednesday Morning. This time, models suggest stronger cape values of 400 to 1000J/kg with 0-3km helicity values 200 to 300m/s. The threat Late Tuesday Night will once again be for damaging winds and an isolated tornado. A surface high pressure system will settle over Mississippi Thursday and the upper level ridge axis will remain over the Great Plains eastward to the Southeast Atlantic Coast through Friday. Expect quiet and cooler weather with a returning chance of clouds and showers for the weekend. This time though, a chilly rain is all that would occur.