In the animation below, LPW 0.9-0.7 rapidly increases, from near 0.39 in the area near 1630Z, to as high as 0.6 by 2000Z, then quickly to 0.65-0.71 only 30 minutes later. Initiation was very near 2000Z.
Before 2030Z, the area of maximum LPW had relatively thin cirrus moving over. After 2030Z, thick anvil quickly moved over the area of maximum depicted moisture.
ENI lightning is overlaid. Lightning first appears at 1958Z.
On a side note, I initially launched LPW stand-alone. The loop had some blank frames. On closer inspection, updates happened usually every approx 30 mins, but occasionally, a frame would update only one minute after the last, causing the blank frame.
The increasing moisture aloft was paralleled by increasing convective parameters as seen in the derived products.
K-Index, a parameter sensitive to mid-level moisture rose from the low-mid 20s before 16Z, to a more convective friendly 30+ by near 1830Z, to remarkably high values near to above 40 by 2000-2030Z. Changes to derived CAPE and LI were much more modest. In the 4-panel below, clockwise from top-left is: derived CAPE, Layer Cloud Type, LI, K-Index(bottom left).
The K-index was also diagnosed as increasing quickly on RAP, but overall values in the model were lower. As seen on the SPC RAP MesoAnalysis, the initial development happened along the moisture gradient at 925mb.
This lends hope that these products will be useful over areas that RAP analysis does not cover, such as oceanic areas.
As a last note, CI didn't show a strong signal beforehand in the area of initiation. There were some transient values above what seemed to be widespread unfocused nominal values 0-20%, but it didn't clearly key in on the cells that went on to develop rapidly. As mentioned earlier, there was some cirrus in the area leading up to development, but it did not seem very opaque.
-Forrest
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