A line of heavy showers moved slowly eastward through north Alabama during the late evening of the 22nd and early morning of the 23rd. Along the line, an EF-1 tornado developed near the Trinity community in Morgan County tracking just under 2 1/2 miles.
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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.
A line of heavy showers moved slowly eastward through north Alabama during the late evening of the 22nd and early morning of the 23rd. Along the line, an EF-1 tornado developed near the Trinity community in Morgan County tracking just under 2 1/2 miles.
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 Oct 22, 6:41 PM CST, 2 hours 59 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Huntsville AL 741 PM CDT Sun Oct 22 2017 .NEAR TERM...(Tonight) Issued at 740 PM CDT Sun Oct 22 2017 Regional radar and satellite show two main areas of precipitation. One being the MCS producing very heavy rainfall across south AL into the western panhandle of FL. The MCS was feeding off very moist inflow air (PWs around 2 inches and dew points 70+) and was slowly shifting eastward. The northern stratiform rainfall was spreading northward into central AL, but was encountering drier air limiting its progression. Other separate bands of showers were advancing northeast through eastern MS and western TN along and ahead of a cold front. Thus far, we have not noticed any lightning activity. RAOBS indicate very little CAPE to work with. However, water vapor imagery shows the strong trough from MO through AR and LA which will negatively tilt and eject east-northeast through the region late tonight into early Monday as an upper/mid level jet and dry slot accelerate the trof passage. The resulting divergence aloft will enhance UVVs and should maintain and possibly expand the area of showers while entering the I-65 corridor and points east. Recent runs of HRRR reflectivity show one main band of showers reaching I-65 from 07-08z, and exiting northeast AL/Franklin Co TN by 13-14Z. Thus, prolonged heavy precipitation is not anticipated for our western counties. Have lowered our QPF thru 06z, with resulting totals of around 1/2-3/4 inch west of I-65, and 1-1.5 inches further east. There is a good amount of veering of the wind profile which will also accelerate later tonight in our eastern counties in advance of the system. The 1km SRH value at 00Z from the BMX RAOB was 230 m2/s2. The limited convective instability should prohibit any sustained rotating updrafts in even shallow convection. .SHORT TERM...(Monday through Tuesday night) Issued at 222 PM CDT Sun Oct 22 2017 The axis of the upper trough will move into northwest Alabama Monday morning, with the surface cold front over northeast Alabama. Lingering showers will begin to taper off by the late morning hours, with much of the precip expected to be out of the area by the afternoon. There is still some uncertainty with the timing of the front. Additionally, wrap around moisture associated with the upper low will move through the area during the day, so kept in isolated to scattered light rain into the afternoon hours. Lingering cloud cover, along with the lowering heights will keep temperatures on Monday in the mid to upper 60s. Dry air will quickly filter into the area Monday night, with dewpoints dropping into the low to mid 40s. Skies will also clear through the overnight hours and combine with light winds to create good radiational cooling conditions. Overnight lows will drop into the mid to upper 40s, which is roughly 10 to 15 degrees cooler than those expected tonight. A reinforcing front is also expected to move through late Monday night/early Tuesday morning as a second upper trough digs southward and through the area. This will send even cooler and drier air into the area, with strong cold air advection during the day Tuesday keeping high temps in the upper 50s to lower 60s despite plenty of sunshine. Another good radiational cooling night on Tuesday will send temperatures down into the upper 30s. Will have to watch for the potential frost development across portions of the area early Wednesday morning. .LONG TERM...(Wednesday through Saturday) Issued at 222 PM CDT Sun Oct 22 2017 A rather complicated and potentially messy pattern to persist into the extended period. By mid week, the medium range guidance is in fair agreement with a rather deep trough positioned across the eastern CONUS with generally northerly flow across the Tennessee Valley. This will pull down rather cool and dry air though it's often hard to time/predict cloud cover in that type of flow regime. Either way, expect temperatures will be quite a bit below normal on Wednesday with some recovery expected on Thursday ahead of the next upstream system. The pattern gets quite interesting toward the end of the week as you have a rather potent northern stream system diving southeast across the Midwest and toward the Ohio Valley. This will aid in cyclogenesis across the Great Lakes and help push a cold front toward the area in the Friday/Saturday time frame. The medium range guidance is not exactly on the same page with the GFS pushing the front through on Friday night with the Euro slower with more energy noted in the southern stream. To add to the confusion, the Canadian has similar timing to the GFS but essentially a dry front with the primary energy off the Florida coast. For now have trended with essentially a blend of the GFS/Euro for timing and discounted the dry Canadian solution. Also trended temps down a notch for Saturday/Sunday given the expected cloud cover with the upper trough passage. Have also kept thunder out of the forecast given the rather limited gulf return and overall cool statically stable lower troposphere ahead of the approaching front. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 610 PM CDT Sun Oct 22 2017 Bands of light shower activity will occur this evening before a more solid band arrives after 04Z at KMSL and 06Z at KHSV. This is when VFR ceilings of 040-080 will drop to around 015agl (MVFR). Winds will shift from southeast to southwest or west after this rain band and cold front move through. Low clouds around 015agl will likely last into much of Tuesday, but with the probability of showers dropping through the day. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && NEAR TERM...17 SHORT TERM...73 LONG TERM...15 AVIATION...17 For more information please visit our website at weather.gov/huntsville.
Hazardous Weather Outlook National Weather Service Huntsville AL 841 PM CDT Sun Oct 22 2017 ALZ001>010-016-TNZ076-096-097-231100- Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan- Marshall-Jackson-De Kalb-Cullman-Moore-Lincoln-Franklin TN- 841 PM CDT Sun Oct 22 2017 This Hazardous Weather Outlook is for north Alabama and portions of southern middle Tennessee. .DAY ONE...Tonight... ...The probability for widespread hazardous weather is low... Isolated thunderstorms are expected overnight head of an approaching cold front. Gusty winds will be the primary threat with any stronger storms that develop. .DAYS TWO THROUGH SEVEN...Monday through Saturday... ...The probability for widespread hazardous weather is low... Showers will taper off from west to east on Monday morning. An isolated thunderstorm is possible during the morning, mainly in northeastern Alabama. .SPOTTER CALL TO ACTION STATEMENT... Activation of storm spotters and emergency management personnel is not anticipated at this time.
The Columbus AFB radar (KGWX), 131 km away, was scanning. The volume nearest the first event began at 03:38 UTC.
1 thunderstorm wind, 1 tornado. Local standard time, as filed.
A tree was knocked down onto Natchez Trace Parkway, just south of the Tennessee state line.
The first indications of damage were just east of the Lawrence-Morgan County line along Ghost Hill Road, where several trees were snapped and uprooted. Damage continued to the east-northeast across South Seneca Drive, Mason Drive, Woodland|Avenue, and South Mountain Drive. In this area, numerous softwood and hardwood trees were snapped and uprooted. Several well-built single-family houses were damaged by falling trees; however, all observed structural damage was caused by trees falling on the structures, not by the tornado itself. The tornado weakened considerably after descending the bluffs beyond South Mountain Drive, but still snapped and uprooted a few trees as it moved northeast toward the intersection of Old Highway 24 and Greenway Drive. The most significant structural damage occurred at an RV/boat storage facility near that intersection, where the tornado lifted and displaced one storage shed, and damaged another. The last indication of damage were snapped, partially-rotted trees northwest of the intersection of Tower Street and Owensby|Way.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2017Every state in 2017This day in weather historyThe tornado archive for Alabama, 2017Warnings in Alabama, October 2017
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: 719680, 719679.