STATUS: 2 April 2018

STATUS: IOP tomorrow

The NOAA P-3 scientists from NSSL, and the University of Oklahoma SMART-Radar crews, are on their way to the Huntsville AL area for operations tomorrow.  This will likely be a one-shot event.  As of midday today, we are anticipating a QLCS (squall line) system to pass through the northern AL area during the evening on Tuesday.

There are a couple of factors that reduce our confidence in tornadoes:  the low-level wind profile has a weakness at about 2-3 km above the ground that we typically do not see in tornado situations.  And the moisture may not be especially rich and deep near the ground.  If the near-ground relative humidity is low, there will be more evaporation of rain and colder outflow, diminishing the likelihood of the near-ground updrafts thought to be important in tornado production.  But it’s always good to be proven wrong… if our knowledge were perfect, there would be no need for VORTEX-SE.

Right now it looks like a another chance of operations toward Friday, and then perhaps a better chance around Monday of next week.

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STATUS: 29 March 2018

STATUS: Operations in progress

VORTEX-SE had a very successful mission yesterday, capturing a QLCS tornado (likely EF1 or stronger) within our ground-based triple-Doppler network near Monroe LA. The NOAA P-3 had a difficult time getting close to this tornado because of storms that kept firing ahead of the main QLCS, but it is quite possible that they got close enough to collect Doppler data. And it’s possible that our overall data sets contain more than one tornado. We won’t know for sure until damage assessments are complete, and the data have been examined.

The P-3 is once again airborne, headed toward southern AL. This aircraft can obtain Doppler radar data sets that are worthy of research even if no ground-based systems are available. Today, the activity will be southeast of either of our subdomains… these are areas where the terrain and land use allow us to collect data with mobile Doppler radars and other instruments.

We expect a lull in the data collection for the next few days, with perhaps an uptick toward the middle of next week.

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STATUS: 28 March 2018

STATUS: Operations in progress

As of 2 PM, VORTEX-SE operations are in progress. The NOAA P-3 aircraft is over Mississippi, heading west to begin studying the storms that are moving into western Louisiana.

The University of Louisiana at Monroe is preparing to launch a sounding from campus. Current analyses suggest that the air north of Monroe is perhaps too stable near the ground for much tornado potential, whereas south of Monroe it appears to be more unstable. This sounding will help us assess this issue.

The research radar at the University of Louisiana at Monroe is operating.

The University of Oklahoma SMART-Radars are enroute to their locations in the Monroe subdomain, where they will gather data that will be combined with the ULM research radar and the NOAA P-3 data. The SMART-Radars should be operating around 3 PM.

We expect a QLCS to move through the Monroe subdomain later this afternoon, with decent potential for updraft rotation, and a slight chance of a tornado. Our primary goal is to collect radar data that can help us design better ways to observe Southeast US storms as VORTEX-SE continues.

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STATUS UPDATE: 19 March 2018

STATUS: Down

The IOP is completed. Several tornadic supercells were observed, with a number of tornadoes occurring. The level of damage is not clear yet.

We succeeded in collecting many volumes of multiple-Doppler data involving ground-based and airborne radars.

Many soundings were obtained, at an hourly interval, to document the evolution of the environment.

The next potential for operations appears to be toward next weekend.

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STATUS Update: 19 March 2018

STATUS: Operating.

One supercell with a low-level meso is moving through our multi-Doppler coverage northeast of Huntsville; the P-3 has been scanning this storm for most of its life. No tornadoes from this so far… lots of hail. This is the kind of data set we were seeking this year to test approaches to measuring 3D winds using multiple simultaneous Doppler radars.

Another supercell is forming south of Huntsville and moving toward Sand Mountain, also in good multi-Doppler coverage. This provides an alternative target for the P-3 aircraft if they have trouble scanning the northern storm.

New storms are forming in MS and will move into AL in a couple of hours. Low-level hodographs are starting to lengthen. A PDS tornado watch has been issued for all of our study area.

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STATUS: 19 March 2018

We are operating. All five ground-based radars are scanning, and the P-3 aircraft is attempting to find a way to scan the storm in NW AL. This storm has a tornado warning, and we suspect it will stay connected to the surface warm front as it continues east toward the Huntsville area in about an hour. Thereafter, it will enter our Doppler radar domain.

We still anticipate another round late this afternoon/evening.

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STATUS update: 18 March 2018

We have just finished our planning meeting. A number of sounding and profiling systems will be deployed across northern AL in the morning on Monday. We still expect a line of supercells to initiate around 2 PM in far eastern MS, and move east across northern AL at about 50 mph. The NOAA P-3 aircraft will take off from Huntsville at 2 PM. We expect the supercells to pass Huntsville around sunset, and then move on into Georgia. We will have five radars on the ground… ARMOR, two SMART-radars, MAX, and the Hytop WSR-88D, and these will be covering all of NE AL and far southern TN, generally east of I-65.

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STATUS: 18 March 2018

STATUS:IOP

We have moved the U. Oklahoma SMART-Radars to the northern AL subdomain at Huntsville, and all the needed platforms should be available for a mission tomorrow (Mon 19th).

Despite small run-to-run fluctuations, the numerical guidance continues to show the potential for tornadic supercells in the domain tomorrow. Some significant tornadoes may occur. This overall theme has been present in the forecasts since Thursday morning, but that’s no guarantee that it will come about.

I sent a special heads-up email this morning to a group of more than 20 researchers in the social, behavioral, and engineering sciences because many of these folks are engaged in studying how the lead-up to tornado events influences reactions to an actual threat, and many of them need to do research immediately following tornadoes or tornado warnings. We all hope for no suffering, while still being ready to learn how to reduce or prevent the suffering caused by future events.

Right now, we are expecting convection to develop in eastern MS around 2 PM, and sweep east across AL and into GA by sunset. The P-3 aircraft is scheduled to take off at 2 PM on Monday.

I will try to post an update just prior to our observing mission… midday Monday.

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STATUS: 16 March 2018

STATUS: IOP today through Monday

VORTEX-SE will be conducting observations over the next several days that are primarily designed to improve our approaches to storm studies in the Southeast.

The brand new University of Oklahoma SMART-Radar has joined the existing SMART-Radar in the Monroe Louisiana area this evening. We have been fairly confident for the past two days that there would not be initiation of significant convection in that region, but we have the radars in place just in case. If a cell(s) formed this evening, we would be able to obtain multiple-Doppler observations teaming up with the University of Louisiana-Monroe S-band research radar. But the atmosphere is gradually stabilizing and quieting down in that area, and research-worthy storms are very unlikely this evening.

Starting tomorrow (Saturday/17 March) our focus will shift up to the northern Alabama subdomain near the University of Alabama-Huntsville (UAH). There, the two OU radars will team up with the UAH ARMOR research radar and the MAX mobile x-band radar, as well as several other important platforms operated by UAH primarily to measure changes in the lower atmosphere at frequent time intervals. The NOAA P-3 hurricane hunter aircraft is also on standby in Huntsville, their base for this spring.

On Saturday and Sunday, strong upper winds will persist across most of the Southeast, and CAPE will gradually be increasing as moisture advances slowly northeast from the western Gulf of Mexico. At just about any time Saturday and Sunday, potentially tornadic (very low probability) storms are possible in the northern Alabama area, so it’s best for us to shift our resources up to that area.

But the main consideration in our decisions today is that the models are suggesting a very potent set up across northern AL on Monday. The forecast looks perilous, and experience suggests that often forecasts of large severe weather probabilities this far in advance do not pan out. But we are watching Monday warily.

Our IOP will likely end Monday night, with a few days of quiet and rest in store after that.

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