Today two new forecasters will examine the 24 May 2008 Oklahoma LMA case that was also done yesterday.
See the end of this post for several concrete recommendations of enhanced plot types suggested by the forecasters.
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A first reaction from the first few frames of total lightning data: Learning curve associated with the change from ground strike lightning data to total lightning data. The larger flash rates require recalibration on what rates are typical.
18:05 - Weakening trend noted in both ground and cloud flash rates. Down to 18/min in Psuedo-GLM. Also tracking total flash rates vs. 50dBZ height.
Request for max flash rate display (like 88D max dBZ readout) - reduces clicks / exploration to get readout.
18:22 - Starting trend back up in lightning, up to 26/min peak.
"If this comes in every minute, it will definitely beat the radar, since we can spot strengthening/weakening trends prior to the radar data." Conducting real-time test of the that hypothesis via the 50 dBZ comparison.
Again noting dropouts in the archived CG and LAPS data.
"Anything that can give me a few minutes of extra time, I want it. Give it to me." - referring to the total lightning data. Has been switching back and forth between lightning and radar, and carefully monitoring every lightning frame.
18:46 - Southern cell initiated, seen in satellite cooling trends and elevated weak reflectivity core prior to ocurrence of lightning. Explained that since lightning requires precipitation-sized ice, this is expected, but is helpful in tracking stages of convective initiation through mature thunderstorm.
18:28 - up to 53/min
19:00 - SVR issued on both storms
19:08 - Lightning in second cell noted as catching up to the first
Again it seems that once the warning issuance process has begun, radar interrogation occupies most of the forecaster screen time. The radar provides evidence of the actual physical manifestation of hail, so this is more worthy of time than a secondary indicator of convective strength in a less-specific sense.
Might consider using sparklines(miniature trend lines displaced slightly from the cell center, with peak and minimum label values) as a low-impedence way to do non-context-switched examination of total lightning trends.
19:19 - "Broad rotation the whole time in northern storm, but hasn't tightened up."
Near the end of the case, lightning was noted as perhaps being more important in pulse storm situations where lightning would be more clearly indicative of important updraft fluctuations. Not so helpful in this sort of case, with little indication in lightning relative to the specific tornado times (or hail presence, which was already well-determined by radar). But great as situational awareness (like MESH) in making sure no dangerous cells are being missed.
Need to have trend plots, because it's too hard to figure out by querying flash count grids. The forecasters preferred a gridded plan view / map mode (not a line graph), and either a plot of (1) the flash rate derivative or, in the lightning jump sense, (2) the number of standard deviations (possibly fractional, e.g., 1.5) relative to the running mean. This could be implemented using the WDSSII k-means cell shape colored according to the above trend metrics. 30 min time lapse trend swath would also be helpful.
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