4/18 – Rob Knight’s “SEVERE THREAT” Thursday Forecast
Main forecast issues primarily in the first 18 hours of the forecast. Potentially pretty significant severe weather/excessive rainfall/wind issues to deal with.
Short term guidance indicates that precipitation should remain fairly isolated through the morning hours before a line of convection reaches the Atchafalaya River Basin around 12 PM. The line will progress eastward across the area before exiting into Alabama in the 9 PM – 12 AM Friday time frame.
All modes of severe weather will be possible if not likely. Entire area outlooked for Enhanced Risk of severe weather and Slight Risk of Excessive rainfall.
Winds will ramp up over the land areas today as the surface low move across the Lower MS Valley. This will lead to winds ramping up around midday. Combine that with a developing Low-Level jet and we could easily see numerous gusts of 35 to 45 mph possibly even topping out around 50 mph in a few locations much like this past Saturday. This could lead to some light tree and power line damage once again outside of any thunderstorm activity.
Once the convective/heavy rain/wind threats move eastward tonight, we’ll still have to deal with the upper low moving across the area on Friday. A good bit of cloud cover can be expected with the upper low. There are some indications that airmass may be unstable enough for some convection Friday afternoon that could produce small hail, even if it doesn’t produce lightning. Any of this convection would dissipate after sunset.