Mission #1
P-3
D. J. Raymond flight scientist
ITCZ pattern
Note -- With minor exception, we neither sought or avoided convection,
but just flew through what was in our path.

All times GMT

1458 - Taxi.
1506 - Launch.
1527 - Trade cu, isolated deeper cu.  Operating at 6000 ft.
153928 - Cloud penetration -- rain.
154030 - Out of rain.
1547 - Cbs ahead.

Doppler is set up with pulse width = 0.500 microsec, dual PRF =
1600/1200, max range 77 km, Nyquist vel 36 m/s.

1600 - As we go south, T decreases, T_d increases.
1609 - Cbs to left and right.
1612 - Penetrating weak point in line.
161255 - Rain.
1617 - Understratus.  No rain.
1620 - We weren't in FAST mode on the radar to this point.  We
are now.
1620 - 93 W, 12 N.
1631 - Convection to west.
1636 - Suppressed to E - trade cu ahead.
163738 - Punch top of decaying small cu.
1644 - Fairly suppressed, small cu.
1646 - Suppressed to E, deep conv. to W.
1656 - Cb visible to SE.
1709 - Rainshowers to SW.
171000 - Punch small cu -- nearly soldi line of deep convection
visible to S.
1715 - 93 W, 8 N.
1719 - Heading into region of deep convection.
172134 - Going W along S edge of deep convection.
1727 - Lots of deep conv -- depth about 13 km on radar.
1730 - In rain.
173125 - 94.3 W, 8 N.
1732 - Pilots avoiding 50 dBZ.
1741 - Still a lot of convection to right.  Temps are lower and dewpts
are higher in deep conv areas even out of rain.
1749 - Lower theta-e's in areas of convection in this region.
175029 - In rain.
1808 - Still deep conv. around, but decreasing.  No low clouds.
1825 - Area of mainly low clouds with isolated deep convection.
1827 - 94.3 W, 12 N.
183552 - 95 W, 12 N.  Clear but with a few Cb to N -- more to S.
1840 - In a region of growing cu.
1844 - 95.7 W, 12 N.
1917 - Going thru region of growing cu.
1921 - Looks like MCS  to SSE of us.  Radar makes it lool like a squall
line moving W with trailing stratiform.
1931 - Squall line visually obvious to S and E -- layered cloudiness
above us.  The system is not particularly deep on the radar -- 10 km.
Environment has gotten more moist.
193754 - Rain.
193831 - 95.7 W, 8 N.
1942 - Broken clouds below us, not attached to surface BL.  Deeper
convection to N.  (Tops to 4 km?)
1946 - Big Cbs far to S.  Layered clouds near our elevation.
1957 - 97 W, 8 N.
2001 - Some stratiform above us.
2007 - Still stratiform in marine layer.  Cb directly N of us.  Growing
mass of clouds to W of us.
2009 - Still lots of layered clouds.
2018 - Out of layered cloud area, heading into deep convective region.
2022 - Going along E side of conv. region -- rain to W.  Under
stratiform cloud.  system to W about 15 km deep.  The theta-e is
low -- we must be in the mesoscale downdraft outflow of this system.
202807 - In rain.  Heading for high reflectivity.
203020 - Heavier rain and bumps.
203140 - Good bumps.
203207 - Into clear -- heading through towering cu.
2034 - Region of towering, growing cu.
2045 - Transiting clear region -- another EW rainband ahead.
205416 - Rain.
205525 - 97 W, 12 N.  Out of rain.  Heading for Huatulco.  Low
clouds with strong easterly shear to NW.  Will remain at 6000'
all the way to Huatulco.
2057 - A few isolated deep rainshowers to NE.  Just low clouds to NW.
2150 - On approach to Huatulco.