For Wednesday, the groups began operations in the Fort Worth and Pueblo CWAs. It quickly became apparent that Pueblo activity would remain marginal, so that group moved to the Springfield CWA. With convection slow to develop in FWD, that group transitioned to the San Angelo CWA.
LAP
- It showed abundant isntability in central Texas. CAPE, LI, and PW were all on par with what we had expected.
- Looking at layer PW in Pueblo, there was an enhanced area of ll moisture in the SE corner of the state, but activity never made it there to tap into it.
CI
- CI values increase quickly before initiation.
- It was helpful in highlighting development along the outflow boundary, and where along the outflow convection would develop.
- Early on, there were low percentages where nothing happened, so did not see any false alarms.
- It hit on storms in the Midland area where we weren't really expecting any development.
- In Springfield, one cell popped up right on the boundary that eventually produced severe hail near St Louis. It had very high regular CI, and 70 severe CI.
- I noticed regular CI hitting on development south of Pueblo CWA.
ProbSevere
- Our one hail-maker in St Louis made it into the 90s. ProbSevere did well on that cell. Otherwise, we didn't see many storms go over 10, which was good since we didn't have any other severe.
- In Texas, I saw my first 100. Mesh was over 2" We issued a tornado warning on that storm.
SRSOR
- I wrote a blog post on the importance for forecasters to back up and look at the wider view, noting important features. As more OTs develop, one can visualize the linear structure across the region. One could see the evolution of boundaries and their interactions with each other. Inflow into storms from the south was apparent via the movement of low level clouds. While the initial outward expansion of teh anvil was in all directions, it backed up on one side due to the opposing mean flow at that level. Lots of waves were apparent. There are a lot of features and processes that you just cannot see with routine data.
- There was a mature storm with large anvil. New storms formed beneath the anvil along the outflow boundary. We could see the storms mature as they rose through the anvil.
- With a cell in Springfield, the updraft looked vigorous but then died quickly. We could see this in the 1-min imagery as it happened. The 1-min imagery has been helpful for rapidly developing storms, allowing you to see what is happening right away.
SRSOR winds
- In Springfield, as cu developed, winds were available at many levels, allowing us to analyze the presence of directional shear (winds were veering with height). South of our CWA, we saw low level convergence, but in our area, flow was uni-directional. That convergence never made it into Springfield, and the lack of low-level support is likely why convection did not develop.
- In San Angelo, convergence was apparent along the outflow via the satellite-derived wind field.
Lightning Jump
- With storms in Texas, a 3-sigma lightning jump helped me make my warning decision.
NUCAPS
- Pueblo is not an upper air site, so it was helpful there. IASI NUCAPS indicated only weak instability, which made sense given only weak convection/showers. Surface dew point and temperature were very accurate, perhaps because the atmosphere was so dry.
- In Texas, we used NUCAPS in our early analysis which proved to be helpful given sparce UA obs.
- NUCAPS had Wet Bulb Zero heights around 9000 ft, and FL around 12000 ft. Wit the kind o updrafts we had, I am not surprised we had such large hail.
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