Scientific crew | |
Chief Scientist | J. Gamache |
Doppler Scientist | P. Dodge |
Cloud Physics Scientist | J. Roles (AOC) J. Barr (AOC) |
Dropwindsondes (listening) | R. Burpee |
Visiting Scientist | J. Lawrence (UHouston) |
This document is divided into 3 sections (Each section is written by the Chief Scientist):
We reached the IP (16.6 N, 117.9W), and proceeded S toward the eye. At 16.2N, 117.9W, the first AXBT was dropped, and was good. The winds on the N side of the eye had an approximately 100-kt maximum. The minimum extrapolated surface pressure was 954 m b, and the storm center was found near 15.7N, 117.9W. As we proceeded toward the southern eyewall, we saw an unbroken region of ~45 dBZ or more; however, the flight through the wall was not rough.
A wind maximum of ~110 kt was seen. At 1953 (15.2N, 118.0W), a second AXBT was dropped. We reached the southernmost point of leg 1 at 1957 and proceeded ENE to point 3. At 2005 (15.2N, 117.3W) we reached point 3 and turned NW. On the SE side of the st orm we found maximum winds of 120 kt, and then located the storm center near 15.9N, 118.0W. We reached the point farthest NW (point 4) at 2030 (16.5N, 118.8W), turned, and tracked 220 deg. to point 5, which we reached at 2040 (15.9N, 119.0W). During th is downwind leg the radar computer system was down from 2032-2035. Contrary to Murphy's law, this down time was during a downwind leg and was simultaneous with the down time on N43RF, and thus no data were lost during the radial legs. N42RF tracked E, an d found the center at 15.9N, 118.1W, with an extrapolated minimum surface pressure of 949 mb. Winds speeds of 130 kt were on the E side of the eye. We continued eastward, dropping an AXBT at 2059 (15.9N, 117.5W) that provided only a few data before fail ing, and reaching the eastmost point of the third leg at 2103 (15.9N, 117.2W). After travelling NNE to point 7 (16.4N, 117.4W at 2110), we dropped an AXBT that was good. We travelled SW, dropping another AXBT at 2119 (16.1N, 118.0N) that was bad. A win d maximum of 115 kt was found in the NE eyewall, while a 105-kt wind was found in the SW eyewall. We reached point 8 (15.4N, 118.8W) on the SE side at 2134 and point 9 (15.0N, 118.2W) on the S side at 2142. N42RF executed a 20 deg.-bank purl while coord inating, and turned directly N toward the center. The center was found on this leg at 16.0N, 118.3W, with an extrapolated minimum surface pressure of 947.5 mb. A 115-kt wind maximum was found in the N eyewall, and we arrived at point 1 (or the IP transl ated by the amount of motion of the storm) at 2209 (16.7N, 118.2W). We decided that we had time for two more passes through the storm, so we did a 90-270 turn and headed S again, finding a 117-kt wind maximum, and an extrapolated minimum pressure of 948. 5 mb at the center. We reached the S point (15.3N, 118.3W) at 2235 UTC, and turned around again to head N. During this last pass we found a 108-kt wind maximum in the S eyewall, a 119-kt wind maximum in the N eyewall, and a 948 mb center at ~16.2N, 118. 3W. The pattern ended at 2302 at 17.1N, 118.3W.
A number of HRD researchers are interested in the data, including at least Hugh Willoughby, Peter Black, Jimmy Franklin, as well as Frank Marks and me. Improved description of structure and intensity change should result from the analyses of these data, and new and old ideas regarding eye dynamics and inner-core evolution should be evaluated.
The listening to the signals of ODW's dropped from N43RF was successful. This suggests that one aircraft will be able to back-up the recording of the other aircraft's ODW data during future VME's.