Pewa — 2013

Pewa formed as a tropical disturbance in the central North Pacific and became a tropical depression on 16 August 2013 near 9.2°N, 172.0°W. It strengthened to a tropical storm later that day and tracked generally west-northwest across the central Pacific, crossing the International Date Line on 18 August. Pewa reached its strongest intensity on 19 August and then turned more northwestward before weakening under increasing wind shear and losing tropical characteristics; the system dissipated by 25 August over the far western North Pacific. Pewa did not make any landfalls. It remained well over open ocean for its entire life and no surface reports of tropical-storm-force winds from land stations were recorded. The storm’s maximum sustained winds reached 65 knots (75 mph) with a minimum central pressure of 987 mb at 0600 UTC on 19 August 2013, equivalent to a Category 1 hurricane/typhoon at peak intensity. There were no reports of storm surge or notable rainfall impacts to populated areas in the NHC report. No specific surge heights or rainfall totals at cities or counties were documented because Pewa stayed over the open ocean and did not affect land with measured coastal surge or heavy inland rainfall. There were no confirmed deaths or damage attributed to Pewa. The Central Pacific Hurricane Center recorded no reports of casualties or property damage associated with the cyclone. Noteworthy points include that Pewa was the first tropical cyclone to form in the central Pacific basin in 2013 and the first to originate there since December 2010. Its genesis was not well anticipated early on—the system was given low development probabilities in initial outlooks before rapid increases in those probabilities shortly before formation—and forecast track and intensity skill varied with relatively larger track errors at longer lead times as Pewa moved more poleward than some forecasts expected.