Mission Summary
20181010H1 Aircraft 42RF
Hurricane Michael (AL14)

Aircraft Crew (42RF)
Aircraft CommanderJustin Kibby
Co-pilotNate Kahn
Co-pilotAdam Abitol
NavigatorBrian Richards
Flight EngineerPaul Darby
flight engineerChris Lalonde
flight engineerMike Sanchez
Flight DirectorIan Sears
Radar TechnicianBobby Peek
Dropsonde OperatorSteven Paul
Dropsonde OperatorTodd Richards

Scientific Crew (42RF)
LPSRob RogersHRD
LPSJon ZawislakHRD
RadarAndy HazeltonHRD
DropsondeKathryn SellwoodHRD
RadarBenjamin Jaimes de la Cruz UMiami/RSMAS

Scientific Crew (Ground)
RadarPaul Reasor HRD

Mission Plan :

Conduct EMC-tasked TDR mission into Hurricane Michael, which is now a Category-4 hurricane approaching the Florida panhandle. There is a pocket of low shear to the southwest of the storm and high shear to the north, based on the CIMSS analysis (Fig. 1). However, this could be related to an inadequate removal of the vortex from the analysis, which results in an erroneous inclusion of the upper-level outflow to the north and consequent overstatement of the shear there. Indeed, the SHIPS analysis for this time indicates shear < 10 kt. There is also an indication of an upper-level trough and associated jet streak to the north of the system (not shown), which may be aiding outflow on the north side. The troposphere is moist in the storm environment, both in the low levels (Fig. 1b) and mid- to upper-levels (Fig. 1c). There is, however, an indication of drier air in the low- and mid-levels well-removed and to the west and south sides of the storm. The storm continues to steadily intensify as the coldest cloud tops and pronounced ice scattering, indicative of deep convection, now encircle the eye (Fig. 2). There is still, however, some indication of outflow being restricted on the southwest side of the storm, likely reflecting some southwesterly shear still impacting the core.

The plan calls for a rotated Figure-4 (Fig. 3), with an IP on the north side and an end on the southeast side, with 105 nm leg lengths at 8000 ft pressure altitude. The legs on the northeast and northwest sides will likely have to be shortened, depending on how close the center is to the coast. Dropsondes are planned at the end- and midpoints, as well as at the radius of maximum winds (RMW) and the center. AXBTs will be dropped in combination with the sondes at all end and midpoints and the first, second, and fourth pass. AXCPs will be dropped outside the RMW on the northeast, northwest, southeast, and southwest passes. An AXCTD will be dropped on the third center pass. If an opportunity arises, fly the offshore intense convection module after completion of the pattern on the southeast side.

Figure 3. Proposed NOAA 42 track

Mission Summary :

Take off Landing
Linder-Lakeland, FL 08:23 UTC Linder-Lakeland, FL 14:43 UTC

The aircraft took off at 0823 UTC from Lakeland. The pattern was flown as planned (Fig. 4). Michael's minimum sea level pressure dropped 7 hPa over the course of the mission, as it tracked just east of due north, rapidly intensifying all the way up until landfall. The sea surface temperatures were warm everywhere in the storm environment, > 28 C. Substantial turbulence was encountered on the outbound leg to the northeast, and the eyewall showed distinct polygonal structures, suggesting the potential presence of mesovortices. The real-time tail Doppler radar analysis (Fig. 5) showed that the precipitation field was symmetrically distributed. The wind field at 2 km altitude was strongest and broadest on the east and northeast sides, similar to the previous day's flight. The strongest updrafts were located at the center, and primarily on the upshear side. One dropsonde, in the northwest eyewall, showed an unusual motion that is indicative of an upward movement (Fig. 6) below 900 hPa. This shows strong upward motion at the top of the boundary layer, just below where the horizontal winds were ~140 kt. This "upsonde" feature could be associated with a mesovortex, as suggested by the radar presentation from the lower fuselage radar. There was no opportunity to fly the offshore intense convection module.

The aircraft landed at Lakeland at 1446 UTC.

Mission Evaluation :

The mission generally was a success. Data was collected for EMC in a storm that was rapidly intensifying right up until landfall, an unusual occurrence for tropical cyclones making landfall in the U.S. The only significant problem was a gap in tail Doppler radar collection during the final pass from the northwest to the southeast. The radar system had to be repowered. It is not certain what caused this issue; it may have been due to the turbulence encountered in the outbound leg to the northeast as mentioned above. This outage lasted for ~70 minutes, impacting the data collected and transmitted to the ground as well as the associated radar analyses (e.g., see gap on northwest and southeast sides in Fig. 5).

A total of 26 GPS dropsondes, 19 AXBTs, 4 AXCPs, and 1 AXCTD were released.

Problems :

The only problem was with the ~70 minute tail Doppler radar outage during the NW-SE pass.

Rob Rogers and Jon Zawislak
Oct. 29, 2018

Mission Data :

Flight track with winds

Timeseries wind, SFMR wind, rain rate, altitude and pressure plots

Flight track

Temperature and Moisture

Wind and Atlitude

Flight Director's log | Flight Director's manifest | NetCDF data | serial data
One second data

Lead Scientist's log | Radar log | Dropsonde log | AVAPS log | Air_Sea scientist's log

Page last updated May 23, 2019
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