1900hurricane wrote:While looking back at some satellite imagery from Maria '17, I noticed an interesting feature around the time of peak intensity. Just before 00Z September 20th, there was a large and cold convective burst near the edge of the CDO (still image below, loop here). I'm not sure this phenomenon has a proper name, so for now, I'm going to call it lobing.
https://www.nrlmry.navy.mil/tcdat/tc2017/AL/AL152017/png/Infrared/201709192330_AL152017_abi_Infrared_80.0_covg100p0_res1km.png
Based on recon data, it appears like it might have coincided with a halt in intensification since the previously falling pressure evened out at 909 mb at the 2219Z pass and only varied by a millibar up and down from that number for the next six hours before rising. This lobing phenomenon could possibly be associated with structural changes. Lobing isn't exclusive to Maria '17 either. It appears it has occurred with a number of intense tropical cyclones across multiple basins. Some of the more clear examples are Nepartak '16, Patricia '15, Usagi '13, and Gilbert '88. Patricia '15 and Gilbert '88 each had recon near the time of lobing (near 18Z October 23rd for Patricia and 00Z September 14th for Gilbert), and both cases were similar to the Maria '17 data which showed no appreciable deepening from that time on. Patricia '15 actually began to weaken rapidly, although land interaction may have played a part in that case. Regardless, it may be a good sign to indicate whether an intense tropical cyclone has peaked.
I have noticed thunderstorms near the central dense overcast (CDO) and surprised there is no term for it. I tend to notice those thunderstorms east of CDO when they are past their peak. I have seen that with Katrina before it made landfall.