Irene: (14-15 October 1999)

On Thursday 14 October N43RF was tasked to do a reconnaissance mission into Hurricane Irene while it passed over Cuba with a takeoff from MacDill AFB at 1856 UTC recovering back in Tampa at 0355 UTC. Also made a conscious effort to obtain ocean thermal structure to the north and east of Irene while still fulfilling mission fix requirements.

GPS dropsonde (HSA) data format

Storm/ Date	Aircraft (Duration)	Altitude	Experiment/ Pattern	Comments (expendables)
Floyd
14 October	N49RF (9 h) GPS dropsondes N43RF (9.2 h) mission summary (144 Kb) GPS dropsondes AXBT data One minute listing	45 kft 5 kft	N49RF Synoptic Surveillance. N43RF Reconnaissance/Air-Sea interaction. Fixes at 2100, 0000, and 0300 UTC. AXBT dropped ahead of storm in Florida Straits. GPS sondes in and around areas of active convection.	2100 UTC fix few nm SW of Havana. 0000 UTC and 0300 UTC fixes off shore N of Havana. Maximum sonde surface wind was 46 kts in W wind maxima ~20 miles NW of center (SFMR maximum surface winds ~60 kts). Surface pressure 988 mb at 2100 UTC TA and LF radars and SFMR worked well throughout mission. (11 AXBT, 48 GPS sondes)

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On Friday 15 October N43RF scheduled for Windfields at Landfall mission with take off time 1930 UTC. The landfall experiment included an initial "figure 4", a series of coastal legs along the Keys and up the E coast of FL, and traverses across the Everglades. Because tropical storm-force winds were expected at MacDill AFB, N43RF recovered in Gulfport, MS at 0311 UTC.

Storm/ Date	Aircraft (Duration)	Altitude	Experiment/ Pattern	Comments (expendables)
Irene
15 October	N43RF (9.2 h) mission summary (204 Kb) GPS dropsondes One minute listing AXBT data WC-130	8 kft 5 kft	Windfields at Landfall Experiment N43RF Fig 4 with GPS drops at C-MAN sites and buoys in Keys to improve real-time and post-storm surface wind analyses.. Collected more wave and storm-surge data with SRA. Flight legs had radials off KAMX and KBYX. AXBTs were dropped in Gulf Stream . AFRES recon.	Sondes over Everglades will help describe structure of strong tropical storm/weak hurricane as it moves across land. No hurricane-force surface winds in sonde data even though some dropped in regions with >75 kt flight-level winds. Rapid drop-off in winds with altitude in sondes. Thermodynamic data from sondes over Everglades will help specify stability to explain why high winds did not reach surface. Analysis of Doppler data may provide details of 3-D windfield to complement sonde measurements. (7 AXBT, 26 GPS sondes)

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Updated Wednesday, 24 November 1999