## 4 Results and Discussion  
### Outflow Boundary Detection  
The method described in the previous sections has been applied to a severe weather system, located along the coastal U.S., in order to demonstrate the utility of the UHR product to identify small scale features along an outflow boundary and how those are related to features captured by the lower resolution ASCAT products. First, the method is applied on the lower resolution products, 25-km and 12.5-km, to provide a more abstract form of the detected outflow boundaries. The wind vectors are analyzed along the boundaries and at the vicinity of precipitation associated with them. Subsequently, the method is applied on the UHR product. The results are evaluated based on the precipitation retrievals from ground-based radars and characteristics of the UHR retrieval. In this context, the outflow boundary features detected by the coarser resolutions are considered as truth in order to evaluate the UHR detections, at least at the vicinity of the precipitating system.  
An MCS was present over Houston (TX) on 28 May 2016 that coincided with the overpasses of the MetOp satellite series and was within the range of the KHGX radar. Ground-based radars are a valuable platform to study and detect features associated with convective systems [33; 56; 57; 58]. The evolution of the MCS is depicted in Figure 1 by the radar reflectivity and single-Doppler radar wind-field retrieved at the lowest elevation angle. The overpasses of ASCAT-A and ASCAT-B at the closest times relative to the radar are also indicated (Figure 1b,e). The reflectivity field indicated that the system was slowly moving toward the southeast with the highest reflectivity magnitude reaching 56 dBZ within the convective core. An extensive stratiform region was visible at 3:35 UTC onwards (Figure 1d-f). During the last time step (Figure 1e,f) the system started to dissipate as the reflectivity magnitude decreased within the stratiform and regions of the main convection, although regionally the highest reflectivity remained the same. This reflectivity structure within the MCS is in line with the detailed analysis of MCS in Houze [59]. A similar case of a squall line was studied in Smull and Houze [60]; however, their case was strictly over land. The authors used reflectivity radar data to show that the system propagated towards the east-southeast and system-relative Doppler horizontal velocity to identify the presence of a rear-inflow jet (RIJ), and a gust front marked by strong low-level convergence. Doppler winds at the lowest scanning elevation angle can be representative of the near surface wind-conditions depending on the distance from the radar. Figure 1 was created to identify the structure and propagation of the MCS, along with the kinematic characteristics of the flow. The range rings during the overpasses (Figure 1b,e) are spaced at 50-km distance, where the retrievals at 100 km and 150 km from the radar location are obtained at a height of 1.5 km and 2.8 km, assuming standard beam-propagation conditions. The analysis revealed the presence of a descending rear-to-front flow that was characterized by a strong northwesterly flow reaching a height of 1.5-km. The descending flow (RIJ) typically forms as a response of the latent heat released by sublimation, melting and evaporation below the trailing-stratiform cloud Houze [59]. The RIJ was present during all time steps, fueling the MCS. The increase in the wind speed over a rear-inflow jet was also observed by [PERSON] and [PERSON] [61], who used observations and simulations to understand the mechanisms responsible for the initiation and maintenance of a convective line.