Flight Log for P3 on Mission 4 9 September 2001 David J. Raymond 1429 - C130 launches. 1434 - P3 launches. Local weather, stratiform overcast, occasional light rain. Still signifcant active convection just offshore. 1441 - Reach 6000 ft. In region of strong embedded convection, heavy stratiform overcast. 1445 - Tops of local convection to 16 km or higher. Tail and belly radar going. Up to 50 dBZ at our level. 1454 - Broken deep convection out to 200-300 km NE - SE - SW on radar. 1457 - Lots of whitecaps. In and out of cloud, small cu below. Winds WNW 8 m/s. 1500 - We still have convection visible out to 200 km -- possible attenuation beyond. 1506 - Stratiform area, tops to 10 km. Flight level winds 9 m/s from WNW. No low clouds, but there are whitecaps. Nice brightband on radar. 1509 - We can see edge of stratiform region on radar -- 130 km SE. In cloud with light rain. 1513 - In light rain, RH 86%, so dewpointers are not getting wet at this point. 1519 - FSSP does respond to stratiform rain. 1523 - Getting to edge of stratiform -- some convection around. Tops to 12 km. 1527 - Out of rain region, into layered middle and upper clouds, no whitecaps. Some showers around. 1531 - Whitecaps again. 1533 - Tops exceeding 10 km E. 1538 - C130 at 200 m, just a bit ahead of us. Winds 7 m/s from SW on C130. Mid-level, broken layer clouds. Towering cu to E. Still cells to 10 km on radar. 1543 - C130 at 12 N, turning S. 1545 - Over clear area, 12 N, 93 W, turning S. Winds 7 m/s from WNW. Convective line EW about 250 km S on radar. 1554 - Stratiform rain to SSW, deep convection visible to SSE. Still overcast midlevel layer above us. Large clear region below, a few very small cu W in C-130 region. 1559 - Wind WNW 5 m/s. A few whitecaps. 1607 - Cutting airspeed a bit to avoid running away from C130. We are about even with them now. 1609 - EW line about 60 km ahead -- still over clear region entering area of light rain to west. 1611 - C130 winds, light rain to NW, we are getting rain also. Our winds are 6 m/s from NW. Approaching area of layered cloud which hides convection. 1616 - In cloud and rain. Tops here are 8-9 km. Pretty stratiformy. 1618 - Some tops to 15 km. 161850 - Getting some bumps. However, looks liek monsoon rains on radar. 1622 - C130 in rain, surface winds NW 6-7 m/s. We are past convective line and into clear. Region of layered clouds below us with suppressed BL cu, solid overcast above. Heavy stratiform to W. Tops to E to 15 km. Winds SW 7 m/s, variable. 1631 - Heading into shower -- heavy rain. Tail Doppler signal may be noisy. 163235 - Good bumps. 1634 - C130 just passed 9 N, starting sounding. We are in region of short lines of showers with roughly NE-SW orientation. Flight level winds 10 m/s from SW. Heavy rain. Tops to 12 km. 164147 - We have been in bumps for a while -- no rain now. Radar says we are exiting shower region. 164450 - New activity popping up ahead. Winds 8 m/s SW. 1647 - 93 W, 8 N, turning W. 1649 - Tops of cells to 12 km N. 1650 - Convection to N, layer clouds below us, overcast above us. Winds 6 m/s WSW. 1658 - Solid undercast, solid overcast, shallow shower ahead. 1708 - 94.3 W, 8 N, heading N, C130 at 8.18 N at 500 ft. Stratiform layer above us, layers at various altitudes below us. Good cell dead ahead. Wind W at 6 m/s. 171450 - Into rain. 171940 - The FSSP tends not to see very light stratiform rain. 172549 - C130 going thru clouds with tops about 500 m above them. 1729 - Going thru weak convection with tops to 12 km. 1733 - Tail radar off. 1746 - Tail radar on, but Doppler questionable. In large stratiform region, clear below, no whitecaps. Stratiform originates to E. Another convective patch 100-250 km NW. 1756 - Still over clear region, light rain. 1809 - 94.3 W, 12 N, turn W, broken cloud below, stratiform above, heading for active convective area. 1812 - Into rain. Tops to 10 km. Lots of brightband, even though it is still convective. Wind 10 m/s from W. 1826 - Fiddling with radar again. 1830 - Radar running again. Tops to 10 km. 1831 - 95.7 W, 12 N, turning S. In stratiform cloud. Wind WNW 9 m/s. 1836 - In rain. FSSP has a weak response. 1837 - C130 is at 2500 m in stratiform rain. 1845 - Heading for NW-SE line, 30 km distant. 185101 - Heavy rain and bumps. Some radar tops to 12 km. 185337 - Thru small cu, S of main convective activity. 1855 - Blue sky above, suppressed trade cu below, convective mass to NE. Cbs distant SSE, whitecaps. 1906 - Surface wind SW at 7 m/s -- some whitecaps. Broken patches of cu below. We have some developing shower activity ahead. 191149 - C130 will penetrate shower topping 10000 ft. (More like 5 km on radar.) Lots of whitecaps. 1916 - WSW-ENE line 150 km S -- we won't reach it. 1919 - Heading for shower with 5 km tops. C130 penetrated indicated cloud. 1923 - Radar stopped again. 192524 - Thru cloud. Wind WNW 5 m/s. 1931 - 95.7 W, 8 N, turn W. Lots of whitecaps! From SSW. Radar working. Rain to NW. Layer cloud below us. 1940 - Rain here and to S. N edge of convection zone. Flight level winds WNW 2 m/s. 1955 - We turned N at 97 W, 8 N a few minutes ago. 1958 - To W -- a precipitating cloud with base near us. Can see small cu underneath! Some evidence of low-level cloud streets. It is very humid at our level, which may explain multiple cloud bases. 2008 - C130 will penetrate deep system to W of us -- N/S line ideally located for radar. 2011 - Radar tops to 6-7 km. 2014 - Some tops barely reach 10 km. C130 reports max updraft of 9 m/s. Juat a few whitecaps NE of shower. This will make a good radar/cloud physics study. 2025 - Into region of lots of moderate sized cells. Also, increasing high stratiform to N. Also, lots of small cu in BL. 2029 - C130 approaching a cell with tops to 6-7 km. Still some whitecaps. 2031 - Fairly major shower activity 60 km N. 2033 - P3 penetrating convection. Tops about 8 km. Wind 6 m/s W. 2038 - Approaching EW line, bumpy. Some tops to 15 km, about 10 km where C130 is headed. 204148 - Out N side. 2044 - Cell 40 km NW of us -- should be in path of C130. Mostly clear below us, stratiform over us. 2049 - C130 will penetrate cell with tops to 9-10 km. This cloud looks like it will also be an excellent case study. 2051 - 97 W, 12 N, maintain N heading for a few more minutes. 2056 - Done -- heading for Huatulco. Clear below, no whitecaps, heading for stratiform rain area. 2059 - Rather weak, diffuse cells ahead. 2103 - Stratiform rain area. 2107 - Still over vast clear area, under stratiform. 2115 - Still clear below, stratiform above, some whitecaps. Stratiform tops to 11 km. 2119 - Through rain. Winds W at 11 m/s. No whitecaps. Getting into a convective area. E-W line 80 km ahead. 2123 - Coming up on field of trade cu. Still in stratiform rain. 2125 - Will penetrate towering cu. 2129 - EW line ahead. 213119 - Penetrating convection -- tops to 12 km, heavy rain. 2135 - Out of cloud, still stratiform cloud all around. Light rain. Wind 2 m/s W. 2147 - Over airport for approach. Overcast here. 2155 - P3 recovers.