Mission 12 28 Sept 2001 P3 - ITCZ - Carlos Lopez flight scientist C130 - ITCZ - Darrel Baumgardner flight scientist, Dave Raymond mission scientist IP will be 94 W, 9 N. 1426 - P3 has 30 min delay -- we will launch on schedule. 1432 - C130 launches. Weather Huatulco -- mid-level overcast. 1436 - Weather offshore -- clear below, no whitecaps. Convection and stratiform to south. 1438 - P3 is realigning inertial systems. 1443 - Wards system (pilot radar recording) is not working -- disk failure. 1445 - Reach ferry altitude of 13000 ft. Under stratiform layer, suppressed cu below. 1451 - In cloud. 1454 - Out of cloud, clear below, no whitecaps, stratiform ahead. 1501 - Under stratiform -- whitecaps below. 1504 - Lots of whitecaps, looks like surface wind from N -- light winds now at flight level. 1525 - Doing calibration mans. Dropsonde showed surface winds 12 m/s from NE. Gap winds! Flight level winds strong from SW. 1532 - Doing reverse track. Through some cloud. The whitecaps are gone here. 1537 - Lots of layer cloud around today. 1542 - P3 launched at 1510. 1557 - We are entering a region of growing convection. Deep/stratiform to E. 1602 - We will penetrate EW line with deep tops, younger E, more mature W. 1605 - Max vertical velocity 8 m/s. 1607 - Heading into clouds with tops just above our level. 1619 - Doing S turns for Ophir check. In clear patch. 1624 - We have a patch of convection, some going deep at about 95 W, 9 N. 1631 - Level 18000 ft, passing to L of tops about at our level -- we will study this patch. 1636 - S of system, Dropsonde. 1647 - Tops are well above us now! 1649 - Radar shows no red. We will penetrate. Note: No trade cu anywhere today. 1653 - Penetrating -- lots of ice crystals. Smaller updrafts (we missed core). 1701 - We have abandoned the deep system and are heading at 13000 ft for a small growing tower with top near our level. 1703 - Going through skinny tower. 1705 - We will penetrate very top of skinny, but more vigorous tower. No whitecaps. 1712 - We went thru another marginal top, heading for a more substantial one on the flank of the old deep cell. This was pretty insubstantial as well. 1720 - Descending to 8000 ft. 1724 - P3 shut down an engine and is heading home. 95.5 W, 10 N possible target from P3 radar. 1734 - We are working just above a stratus layer with cells poking through. Heading for cell with tops a few thousand feet above us. 1748 - At 3000 ft heading into shower line we have been studying. Update on target from P3: 95 W, 10.9 N. 1754 - Let's abandon figure-4 and just do back and forth for 1000 ft and 100 ft legs. 1757 - Heading NE at 1000 ft. In clear region. Some whitecaps from SW. 1801 - Heading into rainband. 1804 - In clear, do 90/270 and make final pass at 100 ft. 1812 - Finish 100 ft, ascend to 13000 ft enroute to 95 W, 10.9 N. 1814 - General conditions -- stratus-topped marine layer, lots of convection and rainshowers. 1830 - Talking to Ron Brown (Walt Peterson). Band 70 km N of Ron Brown, EW orientation. Coordinates of line: #1 - 95.2 W, 10.5 N; 95 W, 10.56 N; 94.79 W, 10.72 N. 1837 - Heading NE to find growing part of line. In stratiform rain. Heading NE end of line. 1847 - Climbing to 18000 ft. 1851 - We have EW line N near 12 N, clear E, going to mature W end, but also growing on S side. 1855 - 18000 ft, approaching growing cells S side of deep convection. 1911 - We are working an MCR near 94.3 W, 12 N. Cells are going deep. 1912 - 13000 ft. 1918 - Another penetration of growing cell at 13000 ft. 1930 - 260X appears to be non-functional. 1941 - Extending box E to include non-developing trade cu. 1946 - We are at 3000 ft over trade cu. We will head W to region of growing cu. 1954 - Back into more active region. 1957 - Punch trade cu. 2003 - Descending to 1000 ft, 90/270. Cloud base about 1400 ft (they were near 1000 ft near 8-9 N). 2007 - In BL under non-precipitating trade cu. Tops not much above 3000 ft. 2015 - Getting into shower/recovery region for original MCR, which is now long gone. The deep convection to the west has gone stratiform. Things are evolving rapidly today. 2020 - 100 ft in clear region, heading for trade cu patch. 2024 - Enter region of trade cu -- can see on SABL. 2026 - Some Cbs forming to E of us (?). When we reach E end of track, we will 90/270 and make a sounding on same track. 2036 - Some tops up to 4000 ft. 2038 - Do a 90/270 to keep sounding over trade cu area. 2045 - Finish sounding, head for Huatulco. Dropsonde. 2059 - Into stratiform area -- rain. 2103 - Going thru cell -- out N side. Dropsonde. 2118 - At 14 N lots of whitecaps still. Clouds are very layered, with not much convection. 2142 - Layer clouds below us, Cbs ahead over land. 2201 - Recover Huatulco. Summary: First MCR was south and produced some deep convection and lots of rain. It evolved rapidly during the study, but continued to present us with fresh cells to study. The second MCR was small and decayed during the study. However, the program evolved into the study of a neighboring region of trade cu, which was judged to be a success. The trade cu showed signs of evolution during the study, tending to grow. Overall this classes as a disturbed day, with lots of rapidly evolving convection.