Fall 2017 – Spring 2018

VORTEX-SE Spring 2018 Experiment Field Catalog

Data Catalog

23 October 2017

Event summary: Largely sub-severe QLCS moved over north Alabama during the overnight hours. An EF1 tornado occurred in Trinity, Alabama, just west of Decatur, around 0822 UTC.

Deployment summary: No formal deployment activities. The MIPS was running at SWIRLL during this event. The EF1 at Trinity was the first TDS captured on the upgraded ARMOR radar.

18 November 2017

Event summary: Severe QLCS moved across north Alabama during the afternoon-evening transition period (~2300-0100 UTC). Two tornadoes were confirmed by NWS Huntsville. UAH personnel assessed damage along 16 additional tracks. Thirteen of these tracks featured at least EF0 damage. The environment was characterized by very low CAPE (150-250 J/kg) and extremely high shear (0-1 km SRH > 400 m2/s2, 0-3 km bulk wind difference ~60 kt). The QLCS was narrow (~20 km wide echo band), low-topped (echo top heights ~20-25 kft ARL), and parallel stratiform in nature, with no evidence of rear-inflow jet development.

Deployment summary: Limited operations were conducted by UAH, consisting of placing the MAX radar at Tanner, Alabama (~17 km from ARMOR/KHSV) and mobile mesonet operations. A circulation with damage estimated at EF1 intensity evolved almost completely within one of the ARMOR-MAX dual-Doppler lobes in the Swan Creek National Wildlife refuge in Decatur, Alabama. The UAH mobile mesonet sampled a peak wind gust of 56 MPH at the Wheeler Marina in Decatur along the southern periphery of a line-break mesovortex.

24-25 February 2018

Event summary: Mixed-mode tornado event across W Tennessee, W and central Kentucky, the Missouri bootheel, and the northern Arkansas delta region. The QLCS produced scattered wind damage into middle Tennessee and NW Alabama.

Deployment summary: Full UAH asset deployment across NW and N-central Alabama. Deployment was begun in the mid-afternoon hours of 24 February to account for potential for discrete convection ahead of the QLCS (which did not materialize).

10 March 2018 – VSE Spring 2018 Experiment IOP0

Event summary: Null event. Potential for supercells across Louisiana was not realized due to subsidence over warm sector.

Deployment summary: SMART-Rs deployed in Monroe, Louisiana domain. P-3 flight was conducted on convection in Mississippi and Alabama.

19 March 2018 – VSE Spring 2018 Experiment IOP1

Event summary: Focused corridor tornado outbreak and extremely large hail event across far NE Mississippi, N Alabama, far S Middle Tennessee, and NW Georgia. Event began with two primary tornadic supercells, one classic cyclic supercell along the Alabama/Tennessee border and one large, cyclic HP supercell that formed near Belmont, Mississippi, and moved all the way across north Alabama and into NW Georgia, producing at least a dozen tornadoes. The “state line” classic supercell produced at least 3 tornadoes, including a long-lived EF2 across Limestone and Madison Counties. Behind the leading HP supercell, numerous additional supercells formed across N Alabama. One supercell produced giant hail up to 5.38″ in diameter near Cullman, and another trailing classic supercell produced a large, long-lived EF3 that struck Jacksonville, Alabama.

Deployment summary: Full VORTEX-SE 2018 deployment, including UAH assets, SMART-Rs 2 and 3, and CLAMPS-2. The domain was focused across N-central and NE Alabama, with SR2 at Grove Oak, Alabama, SR3 at New Market, Alabama, and MAX at Sylvania, Alabama. Notable datasets include the “state line” supercell passing through the ARMOR-SR3 dual-Doppler lobe, the UAH M3V mobile mesonet sampling the RFD of the long-lived initial HP supercell atop Sand Mountain near Boaz, Alabama, and the UAH MoDLS Doppler wind lidar and radiometer sampling the passage of a tornadic mesocyclone over its location at Falkville, Alabama, as an EF1 tornado occurred about 1 mi. to the south.

28 March 2018 – VSE Spring 2018 Experiment IOP2A

Event summary: Event consisting of weak QLCS tornadoes across N Louisiana and into central Mississippi.

Deployment summary: Monroe domain deployment. P-3 spotted three EF1 tornadoes in Mississippi during its flight.

29 March 2018 – VSE Spring 2018 Experiment IOP2B

Event summary: Mostly sub-severe convection across N and central Alabama.

Deployment summary: Very limited UAH operations across N-central and NE Alabama. P-3 flew convective line in central Alabama.

3 April 2018 – VSE Spring 2018 Experiment IOP3

Event summary: Significant, damaging QLCS event across all of N Alabama. The worst damage was concentrated in areas along the Tennessee River. Data from mobile and research radars and extensive survey efforts by UAH and OU personnel identified at least 18 likely tornadoes, with several other polarimetric TDSs identified but not surveyed. Five of these likely tornado tracks occurred in the city of Decatur, leading to extensive damage to numerous homes and businesses, mostly from large fallen trees. The environment was highly atypical of most Southeast tornado environments, with MLLCL heights ranging from 1400-1600 m AGL in all observed soundings ahead of the QLCS. The PBL remained well-mixed long after sunset, with near-adiabatic lapse rates over 1 km deep as late as 0300 UTC, even into the near-storm inflow of the QLCS.

Deployment summary: Full VORTEX-SE 2018 deployment across NW and N-central Alabama and far S Middle Tennessee. SR2 was located at Florence, SR3 and RaDAPS were located at Courtland, MoDLS was located at Salem, Alabama, and a sounding team was placed in Lawrenceburg, Tennessee. SR2, SR3, MAX, and ARMOR all captured close-range observations of mesovortices at the leading edge of the QLCS, while the MAX surface tower recorded a peak gust to 30 m/s (67 MPH). Polarimetric TDSs were recorded on SR3, MAX, and ARMOR. At least 3 separate circulations with TDSs were observed within 10 km of SR3, and 2 circulations with TDSs moved into the ARMOR cone of silence, causing EF0 damage around Huntsville International Airport. Both the KHSV (Huntsville) and KDCU (Decatur) ASOS sites were directly impacted by weak tornadoes, with KHSV recording a peak gust of 61 kt (70 MPH) and KDCU recording a peak gust of 63 kt (72 MPH). UAH and OU personnel conducted dozens of hours of detailed ground surveys in the days after the event, particularly focused along the AL Hwy 20/Alt U.S. 72/I-565 corridor from Muscle Shoals to Decatur to Huntsville.

6 April 2018 – VSE Spring 2018 Experiment IOP4

Event summary: WNW flow severe event across NE Texas, N Louisiana, and the middle Mississippi delta. Supercells grew upscale into a QLCS during the evening hours, producing wind damage and a few tornadoes.

Deployment summary: SMART-R, P-3, and sounding operations in the Monroe, Louisiana, domain.

9 April 2018 – VSE Spring 2018 Experiment UFO1

Event summary: Fair weather day in north Alabama.

Deployment summary: Clear air PBL deployment over north Alabama, including P-3 flight to test compact Raman lidar and upgraded radar clear-air capabilities.

13 April 2018 – VSE Spring 2018 Experiment IOP5

Event summary: Tornado outbreak across northern Louisiana, extending northward across Arkansas and into southern Missouri. Initial supercells produced numerous tornadoes around Monroe and vicinity, with another batch of supercells producing tornadoes in W Arkansas before growing upscale into a QLCS. A second QLCS later formed to the southwest, producing additional tornadoes in Louisiana, including an EF1 that killed one in Shreveport.

Deployment summary: SR2 and SR3 deployed in the Shreveport vicinity and observed leading-edge mesovortices with the QLCS. The P-3 flew the supercells in N Louisiana and sighted several tornadoes.

14 April 2018

Event summary: Largely sub-severe QLCS across north Alabama. Two areas of severe-criteria damage did occur. One was a possible tornado in NW Limestone County in the morning hours, and one with a surveyed gustnado on Lake Guntersville in the afternoon.

Deployment summary: Limited UAH deployment focused on north-central Alabama from mid-morning through the afternoon hours.

22 June 2018

Event summary: Numerous supercells evolved across north Alabama and S Middle Tennessee during the afternoon and evening hours. While most of the supercells were non-tornadic, one EF1 tornado was observed atop Sand Mountain near Flat Rock, Alabama, and a strong EF2 tornado occurred near Jones Chapel in Cullman County, Alabama, critically injuring 3.

Deployment summary: Profiler obs were gathered at UAH. The UAH M3V mobile mesonet sampled the RFD of a non-tornadic supercell in the early afternoon hours N of Huntsville near Harvest and Meridianville, Alabama.

20 July 2018

Event summary: Enhanced risk bust across north Alabama and middle Tennessee. NW flow supercells were anticipated in the evening hours, but subsidence inhibited convection initiation in an extreme CAPE, moderate shear environment.

Deployment summary: Profiler obs and a few soundings were gathered at UAH.