The storm then made a second landfall 3 h later on the Texas mainland (on the northeast coast of Copano Bay) with maximum sustained winds of 105 kt (54 m s −1) and minimum central pressure of 948 hPa. The eye made landfall on the northern end of San Jose Island, near Rockport, Texas, with maximum sustained winds of 115 kt (59 m s −1) and minimum central pressure of 937 hPa. However, after crossing the Yucatan Peninsula on 24 August 2017, it reformed over the Bay of Campeche and rapidly developed into a category 4 hurricane before making landfall on the middle Texas coast on 0300 UTC 25 August 2017. Harvey started as a weak tropical storm near the Lesser Antilles on 17 August 2017 and then dissipated over the central Caribbean Sea ( Blake and Zelinsky 2018). Hurricane Harvey tied with Hurricane Katrina (2005) as the costliest tropical cyclone on record, inflicting $125 billion in damage, primarily from catastrophic rainfall-triggered flooding in the Houston, Texas, metropolitan area. Blake and Zelinsky (2018) also reported that more than 17 000 people had been rescued and an estimated 30 000 were displaced across the state. At least 103 people died in Harvey-related incidents, 68 of them from direct impacts, including flooding throughout Texas. However, according to Blake and Zelinsky (2018) and others, about 90% of hurricane-related fatalities are caused by coastal and inland floodwaters, and Hurricane Harvey (2017) was no exception. The hazards of hurricanes include strong winds, associated tornadoes, heavy rains, and storm surge. Selecting a value of α = 0.015 and β = 0.600 provided the best overall results, relative to the gauges, but more work needs to be done to develop an automated technique to account for changes in the ambient DSD. We examined the parameter space of two key values in the attenuation retrieval to test the sensitivity of the rain retrieval. No in situ DSD data were available over the study area, so changes in the DSD were interpreted by examining the observed radar data.
All of the retrievals are susceptible to changes in the observed drop size distribution (DSD).
An advantage of using a attenuation-based retrieval is its immunity to partial beam blockage and calibration errors in reflectivity and differential reflectivity. Three different hybrid polarimetric rainfall retrievals were used, along with attenuation-based retrieval that employs the radar-observed differential propagation.
The KHGX precipitation estimates were then compared with the HCFWS gauges.
#Harvey rain totals today full
Rain gauge data from the Harris County Flood Warning System (HCFWS) was used for validation with the full radar dataset to retrieve daily and event-total precipitation estimates for the period 25–29 August 2017. The WSR-88D radar (KHGX) maintained operations for the entirety of the event. Left in its wake was historic flooding, with some locations measuring more than 60 in. Hurricane Harvey hit the Texas Gulf Coast as a major hurricane on 25 August 2017 before exiting the state as a tropical storm on 29 August 2017.
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