Developing empirical lightning cessation forecast guidance for the Cape Canaveral Air Force Station and Kennedy Space Center

Abstract

[1] This research addresses the 45th Weather Squadron's (45WS) need for improved guidance regarding lightning cessation at Cape Canaveral Air Force Station and Kennedy Space Center (KSC). KSC's Lightning Detection and Ranging (LDAR) network was the primary observational tool to investigate both cloud-to-ground and intracloud lightning. Five statistical and empirical schemes were created from LDAR, sounding, and radar parameters derived from 116 storms. Four of the five schemes were unsuitable for operational use since lightning advisories would be canceled prematurely, leading to safety risks to personnel. These include a correlation and regression tree analysis, three variants of multiple linear regression, event time trending, and the time delay between the greatest height of the maximum dBZ value to the last flash. These schemes failed to adequately forecast the maximum interval, the greatest time between any two flashes in the storm. The majority of storms had a maximum interval less than 10 min, which biased the schemes toward small values. Success was achieved with the percentile method (PM) by separating the maximum interval into percentiles for the 100 dependent storms. PM provides additional confidence to the 45WS forecasters, and a modified version was incorporated into their forecast procedures starting in the summer of 2008. This inclusion has resulted in ∼5-10 min time savings. Last, an experimental regression variant scheme using non-real-time predictors produced precise results but prematurely ended advisories. This precision suggests that obtaining these parameters in real time may provide useful added information to the PM scheme.

Spatio-temporal dimension of lightning flashes based on three-dimensional Lightning Mapping Array

“…This value is related to the flash-rate of thunderstorms and may depend on the storm's life cycle as suggested by Stano et al (2010). They found three different distributions of inter-flash time for isolated storms derived from the LDAR network (Rustan et al, 1980).…”

Radar Nowcasting of Total Lightning over the Kennedy Space Center

“…These soundings usually occur prior to convective initiation and are less likely to be contaminated by afternoon convective circulations. Afternoon soundings have also been disregarded in numerous previous studies (Vincent et al, 2003;Lambert et al, 2005;Stano et al, 2010;Clements and Orville, 2008).…”

“…In addition, at close ranges, LDAR seems more skillful at detecting VHF sources from the upper branching of IC channels than from the lower branching of IC channels or from CG channels (Boccippio et al, 2001c Stano et al (2010).…”

“…Methods like maximum time interval between flashes, used in Stano et al (2010), should be investigated. In addition, the utility of VII, which has continued to show promise, should be examined not only for forecasting initiation and cessation, but also for predicting the probability of a certain CG or IC flash rate within storms.…”

A Thermodynamic, kinematic and microphysical analysis of a jet and gigantic jet‐producing Florida thunderstorm

“…One caveat, however, is that while the flash detection efficiency is near 100% within the KSC array of nine VHF sensors, it decreases to approximately 90% at a range of 111 km from the network centroid. Here the jet-producing storms are located approximately 100 km from the network center (Figure 1) which places them outside of the high detection efficiency region [Stano et al, 2010]. In addition, location accuracy depends on the network configuration with altitude and range (azimuthal) errors increasing as a square (linear) function of the distance [Thomas et al, 2004;Murphy et al, 2008;Harris et al, 2010].…”