Operational Pouch-Tracking, Model Performance, Kinematics and Thermodynamics of Observed Tropical Systems during NASA HS3 (2011-2013)

During NASA's Hurricane and Severe Storm Sentinel (HS3) dry run (2011) and two field experiment seasons (2012-2013), the NPS team provided operational forecasts of embryonic tropical systems in the Atlantic. We analyzed wind and moisture forecasts in the comoving framework of each wave/pouch as forecast by the dynamical models ECMWF, GFS, UKMET, NOGAPS/NAVGEM, and HRD's experimental HWRF-Genesis, the latter of which we added to our suite in 2011. During the 2011-2013 seasons, we provided daily (and sometimes twice a day) forecasts for 137 pouches (41, 43, and 53 pouches, respectively), including 37 pouches that developed into systems of at least tropical depression intensity. Although a TD:pouch ratio of 37:137 hints at a high false alarm rate, a summary of diagnostics shows that the models performed well by frequently indicating that non-developing pouches would not intensify. Wind and moisture forecast fields are used to assess the performance of the five dynamical models. In real-time, the model diagnostics helped identify the location, structure, and intensity of potential targets of research flights for the Global Hawk aircraft. Dropsonde data were collected during five flights into long-lasting Nadine in 2012 and during seven flights in five different systems (Erin, P24L, Gabrielle, Humberto, and P37L) in 2013. Analyses of circulation, vertical shear, and vertical alignment suggest an explanation for the long duration of Nadine. Over the course of six days from 14-20 September 2012 during which the storm's inner core winds (intensity) decreased by 20 knots, its size and overall circulation values actually increased. Nadine was tracked by NHC for another thirteen days. Similar analyses of non-developing P24L near Africa and P37L in the Gulf of Mexico are excellent comparisons with developing P25L that became TS Gabrielle. These analyses are also compared with those of developing and non-developing systems from the PREDICT (2010) field experiment.