The Storm Prediction Center has issued a Tornado Watch, in effect until 7 am, for most of Mississippi, right up to the Alabama border.
This storm system is similar in many ways to the one back on March 4. The upper level low is so sharp that warm air has come in aloft, limiting instability despite warm, humid air at the surface. But, wind fields are extremely strong, with large shear. So far today, there have been only 2 tornado reports – one in Texas, one in Missouri, but numerous damaging wind reports.
Wind shear will increase over Alabama tonight, with helicity values over 500 m2/s2 by morning. Right now, it looks like the best instability (still not much) will lag behind the strongest shear. However, with the system having slowed down, there could be a small window where sufficient instability (with dewpoints rising into the mid 60s and upper level temperatures cooling) develops in central Alabama tomorrow morning, between 7 am and noon, for isolated tornadoes.
Any storms may produce wind damage, with very strong winds just off the surface. Winds outside storms could gust over 40 mph, mainly on ridge tops.
