February 11, 2018

A tornado touched down in northwest Jackson county and briefly moved into far southern Houston county. Structural damage was minimal with minor roof damage in Graceville in Jackson county. There was no reported structural damage in Houston county as the tornado tracked through a forested area. Trees were also blown down along the track with a dual-pol tornadic debris signature observed on radar in far southern Houston county due to tree debris. This tornado was rated EF0 with max winds estimated at 65 mph based on the observed damage.

For the first time since January 2017, an event including both flooding and tornadoes impacted our area starting on February 11, 2018. Two tornadoes touched down across inland portions of the Florida Panhandle before sunrise, followed by persistent heavy rainfall that resulted in flooding at several river sites. One of the tornadoes clipped far southern Houston county. As an upper level trough dug southward across the western and central U.S., southerly flow drew moisture from the Gulf of Mexico northward into the tri-state area over the weekend. Upper air soundings measured this increased moisture with precipitable water values around 1.5 inches on Sunday, well above the 90th percentile and a record for the 12z February 11 sounding, although the record for that date and time are below the average max for this time of year. With a cold front and upper level trough west of the area, the persistent deep layer moisture helped to create a favorable set-up for high rainfall amounts. This wet pattern resulted in copious amounts of rainfall across the tri-state region. The highest rainfall amounts were across the Florida Panhandle where 8 to 10 inches fell with localized areas receiving more than 10 inches across coastal Walton and Bay counties. The highest observed rainfall total was in Walton County, where a 48-hour rainfall total of 11.45 inches was recorded. Across southeast Alabama and portions of southwest Georgia, widespread 6 to 8 inches of rain fell. While one Flash Flood Warning was issued, the majority of the impacts from this event were from moderate rainfall rates over a prolonged period of time as convection trained across the tri-state area. These high rainfall totals resulted in numerous road closures across the Florida Panhandle from water covered roads and washed out roadways. In addition, a few roads were closed across southeast Alabama.