Archive March 18-20th, 2018 Severe Weather

BMX:

"More data in from the weather balloon instruments in the air. Nearly 3,000 J/kg for convective available potential energy. We plan to conduct another balloon launch towards 4 pm this afternoon if conditions allow."

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I think I may be getting some hail here soon from that storm to my sw.
 
Storm near the Jefferson/Walker county line is trying to get its act together. Probably producing some solid hail at the moment.
 
South AL Wx said:
BMX:
"More data in from the weather balloon instruments in the air. Nearly 3,000 J/kg for convective available potential energy. We plan to conduct another balloon launch towards 4 pm this afternoon if conditions allow."
Click to expand...

Hey I'm a newbie and not an expert. So, maybe a stupid question: What does that mean exactly?
 
Sharky75 said:
Hey I'm a newbie and not an expert. So, maybe a stupid question: What does that mean exactly?
Click to expand...

There is a lot of energy available for the storms to work with right now (that's what the nearly 3000 j/kg of CAPE is indicating). However, the low-level jet is still farther back to the west, so conditions aren't too conducive for tornadoes at the current time, but that is expected to change later. Here is NWS Birmingham's latest discussion:

"The warm front has moved through much of Central AL this morning.
The frontal boundary can be denoted in the ground clutter from
KBMX. Behind this warm front, we`ve been able to mix out a lot of
the stratus that had been hanging around this morning resulting in
clearing skies and sunshine. Here at EET, we`ve warmed to 75 over
65 with the dewpoints mixing out more (dewpoint was 67 an hour ago
or so). To our west, a boundary has moved through MS and is
entering western portions of Central AL. This boundary has been
able to tap into the instability in the wake of the warm front,
sparking some convection. This is expected to continue to move
eastward across the area, initiating some thunderstorms over the
next few hours. The 16z HRRR initialized well, and has a few of
these thunderstorms developing through about 4-5pm CT. Severity of
these storms is uncertain. With increasing instability this
afternoon, I wouldn`t be surprised to see some of these storm
produce hail and gusty winds. The 18z special sounding from BMX
is showing right at 3000 J/kg CAPE, but the LLJ is still further
west, closer to the dryline in MS, so the low level shear isn`t
impressive. Therefore, the tornado threat with these scattered
storms is limited.

The main concern remains for later this afternoon/evening and into
the nighttime hours. The dryline has moved across the MS river in
the past hour and will continue to push eastward. The higher
resolution models and convective-allowing models show a broken
line of individual cells developing along this dryline and moving
through AL. By this time, the LLJ will have moved into the area as
well, creating quite a bit of curvature in the forecast
hodographs. 0-3km SRH is expected to exceed 400 by 7pm (0-1km SRH
exceed 250) across much of North- Central AL, which is what led
to the increase to a Moderate Risk. Expected impacts remain very
similar to previous thinking - tornadoes (some may be strong),
large hail up to tennis ball sized, and damaging winds.

This line of storms will move from the northwest to southeast
through tonight and should move out of our area by the midnight to
2am timeframe."
 
I’m at McDonalds in Glencoe. Getting an update, and possibly aligning myself for the supercell out toward my west.
 
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