Emily (2017)

A small tropical cyclone formed from a decaying frontal zone in the northeastern Gulf of Mexico late on 30 July 2017. A surface low became a tropical depression at 1800 UTC about 145 nautical miles west‑northwest of St. Petersburg, Florida, and strengthened into Tropical Storm Emily around 0000 UTC 31 July. Steered east‑southeast to east by a mid‑level trough, Emily moved toward Florida, made landfall late that morning, crossed central Florida as it weakened, emerged over the Atlantic on 1 August, lost tropical characteristics by 0000 UTC 2 August, and dissipated shortly thereafter off the southeast U.S. coast.

Emily made a single U.S. landfall near Longboat Key, Florida, around 1445 UTC (10:45 a.m. EDT) on 31 July 2017. At landfall the system’s peak analyzed intensity was 50 kt (about 58 mph) with a minimum central pressure estimated at 1001 mb; it weakened to a depression over central Florida by 0000 UTC 1 August and produced only sporadic convection after moving offshore.

The maximum sustained wind at peak intensity was 50 kt (about 58 mph), making Emily a moderate tropical storm at its strongest. Radar velocity data prior to landfall indicated winds aloft of 55–62 kt, and surface reports included a highest sustained wind of 43 kt (about 49 mph) at the Skyway Fishing Pier near the mouth of Tampa Bay. The best‑estimate minimum pressure was 1001 mb based on an observation at Bradenton.

Coastal tide gauges and station reports recorded storm surge and rainfall across west‑central Florida. Measured storm surge/storm tide values included about 1.75 ft surge and 2.12 ft storm tide at Naples, 1.41 ft surge and 1.55 ft tide at Fort Myers, and 1.14 ft surge and 1.68 ft tide at St. Petersburg (Tampa Bay). Estimated inundation near Tampa Bay locations ranged from about 0.6 to 0.9 ft at several sites. Rainfall totals were locally heavy across the region; the NHC rainfall map shows several locations in west‑central Florida receiving multiple inches, with notable flooding in Polk and Pinellas Counties.

There were no reported fatalities tied to Emily. Impacts included widespread flooding that closed roads and prompted some evacuations in Polk and Pinellas Counties, coastal flooding and road closures in Hillsborough, Manatee, and Sarasota Counties, and an EF‑0 tornado near Cortez in Manatee County that destroyed two barns and several greenhouses. Total damage was estimated near $10 million.

Emily’s formation was relatively unexpected — the system was first given a low chance of development only about 6 hours before it became a depression — and watches and warnings were issued only a few hours before landfall (the Tropical Storm Warning for the west coast of Florida was issued about 4.75 hours before landfall). Official NHC track and intensity forecasts for Emily performed at or better than recent averages, though the sample of forecasts is small.