Evolution of the Tornado and Near-Tornado Wind Field of the Selden, Kansas Tornadic Supercell on 24 May 2021 Using a Rapid-Scan, X-Band, Mobile, Doppler Radar

On 24 May 2021, a supercell in Selden, KS produced tornadoes which were probed by RaXPol, the University of Oklahoma’s rapid-scan, mobile, X-band, polarimetric Doppler radar. According to the National Weather Service, the primary tornado was on the ground for 30 minutes and attained a maximum width of 850 yards as a multiple vortex tornado. Throughout this time, the tornado produced EF-1 damage in and around Selden. RaXPol was deployed twice on this tornado; RaXPol moved once as the tornado was approaching. During the first deployment, data from shortly after tornadogenesis to right after a transition to multiple vortex phase were collected. After rapidly redeploying to a safer location, data were then recorded from the end of the tornado’s multiple vortex phase through its dissipation. While the cyclonic tornado was ongoing during the second deployment, a strong anticyclonic vortex or marginal tornado at the southern end of the Rear Flank Gust Front (RFGF) passed directly over RaXPol. Along with a high-definition video taken of the cyclonic tornado from the first deployment location, the high-resolution data collected by RaXPol throughout the lifespan of both vortices provide a rare opportunity to correlate structural features of the cyclonic tornado, anticyclonic vortex, and cyclonically rotating parent supercell to changes in tornado movement and behavior. Using the data captured by RaXPol, a thorough analysis of the tornado pair and the parent supercell was completed and cross sections through both vortices were constructed through their respective Doppler velocity couplets roughly perpendicular to the radar beam. Ultimately, the RaXPol data help to construct a detailed narrative of the Selden tornado pair. RaXPol observed several important phenomena concerning the Selden tornado pair. Numerous significant shifts in the track of the primary cyclonic tornado were identified, and the tornado as well as its parent low-level mesocyclone were observed to occlude with time leading up to the tornado’s dissipation. During analysis, various Rear Flank Downdraft momentum surges (RFD surges) were identified, and they were found to be of critical importance to the occlusion and track behavior of the Selden tornado. The transition of the Selden tornado into and out of a multiple vortex phase were also observed, and the initial transition of the tornado into its multiple vortex phase was found to be the result of a temporary inflow disruption associated with RFD surges. While the primary cyclonic tornado was ongoing, RaXPol observed two independent anticyclonic vortices with different behavior, including a ‘rogue’ anticyclonic vortex and the marginally tornadic anticyclonic member of the Selden tornado pair. The ‘rogue’ anticyclonic vortex appeared very near the Selden tornado for a brief time, and numerous ideas for its origin and nature are discussed. The marginally tornadic anticyclonic vortex was found to form when a potent RFD surge impinged on the southern end of the RFGF, and the vortex was observed to occlude in a similar manner as the primary Selden tornado leading up to its dissipation

Feasibility of Obtaining Surface Layer Moisture Flux Using an IR Thermometer

This paper evaluates the feasibility of a method using a single hand-held infrared (IR) thermometer and a mini tower of wet and dry paper towels to psychometrically obtain surface layer temperature and moisture gradients and fluxes. Sling Psychrometers have long been standard measuring devices for quantifying the thermodynamics of near-surface atmospheric gas–vapor mixtures, specifically moisture parameters. However, these devices are generally only used to measure temperature and humidity at one near-surface level. Multiple self-aspirating psychrometers can be used in a vertical configuration to measure temperature and moisture gradients and fluxes in the first 1–2 m of the surface layer. This study explores a way to make multiple vertical psychrometric measurements with a single non-contact IR temperature sensor rather than using two in situ thermometers at each level. The surface layer dry- and wet-bulb temperatures obtained using an IR Thermometer are compared to Kestrel 4000 Weather Meter and Bacharach Sling Psychrometer measurements under various atmospheric conditions and surface types to test the viability of the method. To evaluate the results obtained using this new approach, standard meteorological surface data are collected during each experiment, and moisture parameters are derived via psychrometric equations. The results indicate that, not only is the method possible and practical, but they suggest that the IR Thermometer method may provide more surface layer temperature and moisture gradient and flux sensitivity than other single instrument methods

Germline Mutations in NFKB2 Implicate the Noncanonical NF-κB Pathway in the Pathogenesis of Common Variable Immunodeficiency

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by antibody deficiency, poor humoral response to antigens, and recurrent infections. To investigate the molecular cause of CVID, we carried out exome sequence analysis of a family diagnosed with CVID and identified a heterozygous frameshift mutation, c.2564delA (p.Lys855Serfs∗7), in NFKB2 affecting the C terminus of NF-κB2 (also known as p100/p52 or p100/p49). Subsequent screening of NFKB2 in 33 unrelated CVID-affected individuals uncovered a second heterozygous nonsense mutation, c.2557C>T (p.Arg853∗), in one simplex case. Affected individuals in both families presented with an unusual combination of childhood-onset hypogammaglobulinemia with recurrent infections, autoimmune features, and adrenal insufficiency. NF-κB2 is the principal protein involved in the noncanonical NF-κB pathway, is evolutionarily conserved, and functions in peripheral lymphoid organ development, B cell development, and antibody production. In addition, Nfkb2 mouse models demonstrate a CVID-like phenotype with hypogammaglobulinemia and poor humoral response to antigens. Immunoblot analysis and immunofluorescence microscopy of transformed B cells from affected individuals show that the NFKB2 mutations affect phosphorylation and proteasomal processing of p100 and, ultimately, p52 nuclear translocation. These findings describe germline mutations in NFKB2 and establish the noncanonical NF-κB signaling pathway as a genetic etiology for this primary immunodeficiency syndrome

Novel Mutations Identified With Next-Generation Sequencing Expand the Spectrum of PLP1-Associated Leukodystrophy Clinical Phenotypes

Next-generation sequencing was performed for 2 families with an undiagnosed neurologic disease. Analysis revealed X-linked mutations in the proteolipid protein 1 ( PLP1 ) gene, which is associated with X-linked Pelizaeus-Merzbacher disease and Spastic Paraplegia type 2. In family A, the novel PLP1 missense mutation c.617T>A (p.M206K) was hemizygous in the 2 affected male children and heterozygous in the mother. In family B, the novel de novo PLP1 frameshift mutation c.359_369del (p.G120fs) was hemizygous in the affected male child. Although PLP1 mutations have been reported to cause an increasingly wide range of phenotypes inclusive of the dystonia, spastic paraparesis, motor neuronopathy, and leukodystrophy observed in our patients, atypical features included the cerebrospinal fluid deficiency of neurotransmitter and pterin metabolites and the delayed appearance of myelin abnormalities on neuroimaging studies. Next-generation sequencing studies provided a diagnosis for these families with complex leukodystrophy disease phenotypes, which expanded the spectrum of PLP1-associated leukodystrophy clinical phenotypes