Multiple rounds of thunderstorms and showers produced rain amounts of 3 to 5 inches across north Alabama. The heaviest rains were in northwest Alabama around the Quad Cities/Shoals area, and south of the Tennessee River, mainly along and east of the I-65 corridor.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS HUN wrote it up.
Multiple rounds of thunderstorms and showers produced rain amounts of 3 to 5 inches across north Alabama. The heaviest rains were in northwest Alabama around the Quad Cities/Shoals area, and south of the Tennessee River, mainly along and east of the I-65 corridor. This resulted in numerous reports of flash flooding, particularly in the Shoals of northwest Alabama and Cullman County. The flooding prompted the closure of many roads and schools affected by the flooding. The thunderstorms came in multiple waves, one during early morning, another around Midday, with two final waves during the evening hours. Although the majority of severe weather this day occurred south of north Alabama, one EF-1 tornado tracked across northeast Cullman County during the evening hours.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Huntsville, AL wrote its last area forecast discussion before the first event at Mar 17, 2:48 PM CST, 45 minutes earlier.
Area Forecast Discussion National Weather Service Huntsville AL 348 PM CDT Wed Mar 17 2021 .NEAR TERM...(Tonight) Issued at 348 PM CDT Wed Mar 17 2021 A very active/volatile wx pattern continues to unfold across much of NE/east cntrl MS into west cntrl AL this Wed afternoon. Much of the tstm activity is being driven by an active SW flow regime in place over much of the region, ahead of a potent upper low/trough axis rotating ewd thru the mid/srn Plains. A lot of this convection is also occurring along/ahead of a cold front making its way ewd into the Lower MS Valley. The attendant sfc low is also moving east into north AR or the Mid South region, with the associated warm front located from extreme NW MS into NW/cntrl AL. The location of the warm front and how much farther to the north it tracks will be a key factor in the development of strong/severe tstms late this afternoon into this evening. The latest model suites remain fairly consistent with moving the sfc low into KY later tonight, thereby pushing the cold front into the cntrl TN Valley area. This scenario would also lift the warm front into mid/ern TN and allow low-level instability to spread into the area. With Bufr soundings/shear profiles continuing to indicate 0-3km SRH values in excess of 400 m2/s2 and Bulk Shear values near 60kt, a slight increase in SBCAPE values around 500-1000 J/kg would easily favor the development of severe tstms into the evening hrs, with the main threats being damaging winds, large hail and tornadoes. In fact, supercellular structures late this afternoon into this evening could produce a few long track/violent tornadoes, before tstms begin to merge into more of a QLCS line right along the passage of the front. Again, much of the extent/strength of any strong/severe tstms will be heavily influenced by the magnitude of the warm sector into the mid TN Valley area. Considering some of the intense rainfall rates, some localized/minor flooding may also be a threat later this evening in locations which receive multiple rounds of showers/tstms. Lingering showers/tstms should then begin to taper off to the east by early Thu morning following the passage of the front, with lows falling mainly into the lower/mid 50s. .SHORT TERM...(Thursday through Friday) Issued at 348 PM CDT Wed Mar 17 2021 The overall wx pattern is then expected to turn more quiet/seasonal heading towards the end of the work week, as a large area of high pressure out of the nrn Plains builds into the Midwest/OH Valley states. Afternoon highs Thu/Fri look to range from the mid 50/near 60F, while lows Thu night trend in the lower/mid 40s. .LONG TERM...(Friday night through Tuesday) Issued at 348 PM CDT Wed Mar 17 2021 The quiet pattern continues into the weekend period, as the sfc high moves into the mid/NE Atlantic states. This should allow for a gradual warming trend into next week, as highs climb more into the 60s. Optimal radiational cooling may also allow overnight lows to trend in the mid 30/near 40F thru Mon night. The next chance of rain still looks to develop on Tue, as another cold front approaches from the west. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1242 PM CDT Wed Mar 17 2021 Restricted flying conds will be in place for much of the TAF period, as multiple waves of shra/tsra continue to develop/spread across the area well into the afternoon/evening hrs. IFR conds will be possible in some of the heavier shra/tsra, with sfc winds gusting near 30-35kt at times. All of this will be occurring along/just ahead of a cold front approaching from the west. The front looks to move thru the area by Thu morning, with lingering shra/tsra tapering off to the east. Cigs though may hover near 3-4K ft in the wake of the frontal passage Thu morning, as sfc flow turns to the SW near 10-12kt with higher gusts. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && NEAR TERM...09 SHORT TERM...09 LONG TERM...09 AVIATION...09 For more information please visit our website at weather.gov/huntsville.
Hazardous Weather Outlook National Weather Service Huntsville AL 546 AM CDT Wed Mar 17 2021 ALZ001>010-016-TNZ076-096-097-180200- Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan- Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN- 546 AM CDT Wed Mar 17 2021 This Hazardous Weather Outlook is for north Alabama and portions of southern middle Tennessee. .DAY ONE...Today and Tonight... Thunderstorms are increasing across the area as a warm front lifts northward. A few strong to severe storms will be possible early this morning through around 10 AM. The main threats with these morning storms will damaging winds, marginally severe sized hail, and a tornado or two. The main threat area will be along and south of a Waterloo to Moulton line. Scattered supercell thunderstorms are expected again this afternoon, as the atmosphere will become progressively unstable in the wake of the northward- moving warm front. Although storm coverage will be scattered, damaging winds, large hail and tornadoes will be possible. The main threat area will be for strong to severe storms will be for locations to the south and west of Huntsville. A third and more widespread threat for severe thunderstorms will develop ahead of an eastward-moving cold front by late this afternoon, and persist throughout the evening and into early morning hours on Thursday. Strong, long-track tornadoes, significant damaging winds and large hail will all be possible, until the front clears the region shortly before sunrise on Thursday morning. In addition to the threat for severe thunderstorms, multiple rounds of locally heavy rainfall will lead to an enhanced risk for flash flooding today and tonight, as well as river flooding that may persist through the end of the week. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday... No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Activation of storm spotters and emergency management personnel is possible beginning early Wednesday morning. However, activation is likely today through early Thursday morning. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
253 PM CDT WED MAR 17 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0238 PM FLOOD 2 N SCOTTSBORO 34.68N 86.04W
03/17/2021 JACKSON AL FIRE DEPT/RESCUE
ONE FOOT OF WATER FLOWING OVER CEDAR HILL
ROAD AT E. WILLOW STREET IN SCOTTSBORO.
&&
12The Birmingham radar (KBMX), 116 km away, was scanning. The volume nearest the first event began at 21:35 UTC.
16 flash flood, 2 thunderstorm wind, 1 tornado, 1 flood. Local standard time, as filed.
Highway 278 at CR866 closed due to water over the road. Depth of water unknown at this time.
CR1141 at West Point School closed due to water over the road. Depth unknown at this time.
CR 1218 impassable due to water over the roadway between Hwy 157 and CR1216.
Intersection of CR1114 and 1141 closed due to water over the road. Depth of water unknown at this time.
Intersection of CR81 and CR112 closed in Oakland. Depth of water unknown at this time.
Brooklyn Road flooded near Mud Creek north of Holly Pond. Depth of water unknown.
Water over the bridge on CR1755 near Hwy 67. Depth of water unknown.
Rescue squad responding to a swift water rescue on Wilhite Road in Lacon.
Home flooded on Almon Avenue in Tuscumbia. Depth of water unknown.
A large amount of roofing was torn off of a barn on CR 1518 at Bentley Road.
A large tree was uprooted along CR 1488 between CR 1521 and CR 1528.
A tornado began north of CR1605, between CR 1609 and CR 1610. Initially, branches were broken, but the tornado began snapping tree trunks as it crossed CR 747 and CR 1630. The tornado continued northeast and crossed CR 1635, uprooting multiple trees, pulling some roofing material from a site-built home, and damaging or destroying several sheds. From there, the tornado tracked along Alabama Highway 69, causing minor roof damage to a shed, snapping and uprooting several trees, and severely damaging a detached garage. The tornado continued north of Fairview along Welcome Drive and CR 1568, snapping trees and causing roof damage to large farm outbuildings. Roof and tree damage was most significant on CR 1568 and 1569 northeast of Fairview. A large portion of roofing was removed from a house, numerous trees were snapped and uprooted, several large agricultural sheds were demolished, and several chicken houses had roofing and siding removed. At this point, the tornado reached its peak width of approximately 50 yards and peak intensity of 100 mph. The final damage of note was observed along CR 1579 where a few more trees were snapped and the roof was peeled back from a large shed. Little additional damage was noted northeast of this location, so the end point is placed east of CR 1579 and south of CR 1570.
High water rescue underway with an SUV in 4 feet of water near a creek on South Green Mountain Road and Old Big Cove Road. Both occupants successfully rescued.
Road impassable due to rushing water at CR63 at Brush Creek. Depth of water unknown.
Ten to twelve residences near Oakwood Blvd in Sheffield have up to 5 feet of water in them. Retention pond overflowed again into neighborhood.
Significant flooding in Cove Subdivision at Jacks Creek Lane and Pale Dawn. Water covers mailboxes and there are waves in the rushing water moving down the street. Report received via Social Media.
Hobbs Island and Hyatt Intersection flooded with furniture floating in the roadway. Depth of water unknown.
Residence in Laceys Spring at River Loop Road has water standing in the home. Depth of water unknown.
Car submerged at Rock Road at Hwy 72. Water was flowing over the roadway, but depth of water unknown at this time.
County Road 1485 partially washed out in Cullman. Report relayed via Social Media.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2021Every state in 2021This day in weather historyThe tornado archive for Alabama, 2021Warnings in Alabama, March 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 948171, 948172, 948173, 948174, 948175, 948176, 948177, 948178, 948179, 949442, 949443, 947542, 948180, 948181, 948182, 948183, 948184, 948185, 948186, 948257.