Mission Summary
20160923I2 Aircraft 43RF
Tropical Storm Karl

Aircraft Crew (43RF)
Aircraft CommanderScott Price
Co-pilotDanny Rees
Co-pilotNate Kahn
NavigatorPete Siegel
Flight EngineerKen Heystek
Flight DirectorBrian Belson
Flight DirectorIan Sears
Data TechnicianDana Naeher
Dropsonde OperatorBobby Peek
Dropsonde OperatorJeff Hartberger
Scientific Crew (43RF)
RadarBrad KlotzHRD
DropsHui ChristophersenHRD
Ocean WindsJoe SappNESDIS

Scientific Crew (Ground)
RadarJohn GamacheHRD

Mission Plan :

15Z Steering current

15Z Shear analysis

The mission is to conduct a RAPX experiment into Tropical Storm Karl. The storm is at 50kts traveling N at 10-15kts about 750 miles away from St. Croix (Figure 1). Convection is centered over the low level center with a band stretching out to the east. Shear is analyzed at SE 15-25 knots (Figure 2). Track guidance show Karl continuing north before turning NE to the North Atlantic (Figure 3) possibly strengthen to a category 1 hurricane before becoming fully extratropical (Figure 4).

12Z Track forecasts

12Z Intensity forecasts
The plan calls for a butterfly pattern with flight altitude of 7000 feet radar, regular drops at the midpoint s, and IR sonde/AXBT combo drops at the end points (Figure 5a). A possible Ocean Winds module may also be conducted in the region of highest winds during this flight with additional drops. The high incidence SFMR module may also be conducted if there is sufficient time. Upon completion of the mission, the plane will return to St. Croix.

Prepared by the Hurricane Research Division
File: current1.ftk
September 21, 2016
Aircraft: N43RF
Proposed takeoff: 23/1800Z
deg min deg min n mi/deg hr:min
1S27 0365 06 105/1801:44
2S30 3365 06 105/0002:40
3S29 4166 50 105/3003:08
4S27 5663 23 105/1204:03
5S29 4163 22 105/0604:31
6S27 5666 49 105/2405:26
Mission Summary :

Take off Landing
St. Croix, USVI 18:00 UTC St. Croix, USVI 02:00 UTC

Proposed and Actual flight tracks

The butterfly pattern was completed as planned (Figure 5b). Karl continued to travel north at about 10 knots. IR satellite imagery shows a convective burst in the NW quadrant where the radar indicated the strongest winds were located (Figure 6). Shear appears to still be keeping the south and east drier as indicated by dropsodes. The radar analysis shows the strongest winds were on the SE side of Karl (Figure 7). Peak flight level winds were 70 knots and SFMR reached 58 knots in the south. The strongest surface winds from a dropsonde were found on drop 7 with 56 knots. The SFMR high incidence module was performed on the west side out of precipitation. Three banked turns were completed for each angle: 15, 30, and 45 degrees.

IR satellite loop

Radar analyses

A total of 8 regular sondes, 5 IR sondes/AXBTs combos were dropped, 1 lone AXBT and 3 radar analyses were completed.

Mission Evaluation:

This RAPX mission was completed as planned. Three radar analysis were completed and the P3 maintained good radar coverage of TS Karl. While the high incidence module was performed, it may have been in too weak winds. Need to contact Heather Holbach to confirm whether the data was usedful.

Problems :

An externally mounted AXBT malfunctioned and was launched shortly after takeoff. It was replaced with an internally launched AXBT. Some of the AXBT data initially came in spotty.

Mission Data :

Final flight track

Plot of raw High Density Obs

Plot of raw Flight Level winds

Plot of raw SFMR winds

LPS's log | Radar Scientist's log | Dropsonde Scientist's log

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

Page last updated Feb. 1, 2017
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