Flash Flood — Martin, Florida

2020-10-02 · near Stuart Witham Fld, Martin, Florida

Event narrative

Training bands of heavy showers redeveloped across coastal areas of Martin County during the morning of October 2 and persisted into the early afternoon. Rain totals of 5 to 8 inches fell across the same area impacted by 6 to 10 inches only a day earlier. Many of the same areas which experienced flash flooding were again inundated with rapidly rising water, exceeding 3 feet in some areas. High water resulted in the closing of dozens of roadways. Flood waters approached many homes and intruded into several homes resulting in damage. Drainage canals and creeks overflowed and high water from the Savannas Preserve flowed into surrounding areas. The flood waters were very slow to recede.

Wider weather episode

Unseasonably deep tropical moisture persisted across Martin and St. Lucie counties for nearly four days, just to the north of a stationary front. A secondary front then dropped south and stalled across Martin and St. Lucie counties. Moderate onshore flow within the moist air mass, combined with favorable conditions aloft, and resulted in development of several periods of heavy rain along the coast, with training of shower bands. Multi-hour rain rates of 1-to-3-inches-per-hour occurred during three seperate periods between the early morning hours of October 1 and late afternoon of October 3.

Much of this same area was impacted by flash flooding during the early summer and the local water table remained very shallow, resulting in renewed flooding. Numerous roadways became impassable, drainage culverts were overwhelmed, standing water reached three feet or more in some neighborhoods and water entered several homes.

The most significant (flash) flooding affected portions of Martin County (primarily Hobe Sound, Port Salerno and Sewall's Point) on October 1 and 2. Considerable flooding of roadways, drainage canals and yards affected St. Lucie County (primarily Lakewood Park and the southern portion of Ft. Pierce), mainly on October 3.

View location on OpenStreetMap → (27.1729, -80.2229)

Source: NOAA Storm Events Database, event_id 923626. Narrative written by the NWS forecast office that issued the report.