STATUS: Observations in progress

We are conducting a boundary layer heterogeneity experiment.  The convection forecast is extremely murky, and it would take some unforecastable accidents to yield a low-level flow structure supportive of tornadoes.  So we are going to focus on some remaining experiment objectives that have not been fully satisfied.

STATUS: Finished until tomorrow

We observed at least six supercells in the domain today, with reasonably good data collection on several.  One was tornado warned and appeared to be quite close to producing a tornado near Athens.

We are going to reconvene at 9 AM Sunday for a meeting at SWIRLL to plan our final (extra) day of observations.

Tornado sirens sounding in Huntsville.  Storm with intense rotation just west of here near Athens AL.  We have seen a number of circulations today, and are making some good observations.

STATUS: Operations in progress

We are expecting a convective system now in MS to move into AL early this afternoon.  The flow through the lower troposphere is stronger today than yesterday.  The low-level airmass is very inhomogeneous after yesterday’s storms, so it’s hard to anticipate where CAPE will be largest.  The highest dewpoints are to our SW in MS, and with the southwest flow, some of this air should move northward ahead of the incoming convection.

We are setting up one dual-Doppler baseline between ARMOR and Courtland, AL.  Later, we hope to add another mobile Doppler into the mix with a shorter baseline.  Disdrometer and sticknet deployment teams are heading west toward Florence/Muscle Shoals/Tuscumbia.  If interesting storms are targetable west of them, they will deploy.  Otherwise they will wait to deploy their sensors in the Dual-Doppler lobes.

STATUS: Operations today

HRRR guidance has been consistent during the last few hours.  The convective system currently in far western MS is expected to persist, and move into the V-SE domain around 3 PM.  Allowing for a ~2-h error, we might need to have in situ teams into the west end of the domain by 1 PM, and soundings even earlier.  So we will meet at 9 AM at SWIRLL.  This will be our only meeting… there will not be a prepared 1 PM weather briefing.

There will be an email and a status post around 12Z tomorrow/Sat morning, just in case we need to meet in the morning to plan the day’s operations.  Most likely the email will announce that we are waiting until 1 PM for the briefing/meeting, but there is a chance that an overnight MCS will persist and move into AL during the mid/late morning.

We are approaching the end of ops for today.  The richer air didn’t surge north ahead of the convective system as strongly as forecast.  Earlier, there was a fairly intense low-level vortex west of Columbus MS, near where the warm front intersected the QLCS.  But the cold pool eventually overtook this part of the system.  In the main part of the domain, the convective system has been fairly benign.

Next update likely to be tomorrow.

STATUS: Ops in progress

Initial soundings have begun, and all mobile observing crews are now being deployed toward the west.  There is a fairly vigorous QLCS moving through MS, and should enter AL about 21-22Z.  A warm front is lifting slowly N, and might enter the SW part of the domain before the QLCS arrives.  Just along and north of the warm front, low-level shear should be enhanced, increasing the likelihood of low-level rotation.  The QLCS structure and evolution will be influenced by the large gradient in CAPE and low-level evaporation potential across the domain.

Ops are possible tomorrow, with the current expectation being potentially severe activity somewhere in the domain.

There will be other updates today (hopefully).  There will be a 1 PM briefing/planning meeting on Saturday.

STATUS: IOP

It now appears that a QLCS will cross the domain during the afternoon and early evening.  There is some potential for vortices associated with this system.  All participants are invited to report to SWIRLL as soon as possible to begin working on today’s science plan.

STATUS: IOP continues

No significant activity is expected on Thursday.

Another briefing and science planning meeting will be held Friday at 1 PM.  We anticipate the possibility of late-day activity on Friday.  There should be some storms to observe on Saturday, and perhaps on Sunday as well.