Tornado outbreak of April 1977
![]() F5 damage to homes in the Smithfield neighborhood | |
Tornado outbreak | |
---|---|
Tornadoes | 22 |
Maximum rating | F5 tornado |
Duration | April 4–5, 1977 |
Overall effects | |
Fatalities | 24 (+72 non-tornadic) |
Injuries | 158 (+22 non-tornadic injuries) |
Damage | $32,723,500 ($164,530,000 in 2024 USD) |
Areas affected | Southeastern United States, particularly Alabama and Georgia |
Part of the tornadoes and tornado outbreaks of 1977 |
A violent severe weather outbreak struck the Southeast on April 4–5, 1977. A total of 22 tornadoes touched down with the strongest ones occurring in Mississippi, Alabama, and Georgia. The strongest was a catastrophic F5 tornado that struck the northern Birmingham, Alabama, suburbs during the afternoon of Monday, April 4. In addition to this tornado, several other tornadoes were reported from the same system in the Midwest, Alabama, Georgia, Mississippi and North Carolina. One tornado in Floyd County, Georgia, killed one person, and another fatality was reported east of Birmingham in St. Clair County. In the end, the entire outbreak directly caused 24 deaths and 158 injuries. The storm system also caused the crash of Southern Airways Flight 242, which killed 72 and injured 22.[nb 1]
Outbreak statistics
[edit]Date[nb 2] | Total | F-scale rating[nb 3] | Deaths | Injuries | Damage[nb 4] | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|
FU | F0 | F1 | F2 | F3 | F4 | F5 | |||||
April 4 | 19 | 1 | 1 | 5 | 9 | 2 | 0 | 1 | 24 | 157 | $29,948,500 |
April 5 | 3 | 0 | 0 | 2 | 1 | 0 | 0 | 0 | 0 | 1 | $2,775,000 |
Total | 22 | 1 | 1 | 7 | 10 | 2 | 0 | 1 | 24 | 158 | $32,723,500 |
State | Total | County | County total |
---|---|---|---|
Alabama | 23 | Jefferson | 22 |
St. Clair | 1 | ||
Georgia | 1 | Floyd | 1 |
Totals | 24 | ||
All deaths were tornado-related |
Confirmed tornadoes
[edit]FU | F0 | F1 | F2 | F3 | F4 | F5 | Total |
---|---|---|---|---|---|---|---|
1 | 1 | 7 | 10 | 2 | 0 | 1 | 22 |
Prior to 1990, there is a likely undercount of tornadoes, particularly E/F0–1, with reports of weaker tornadoes becoming more common as population increased. A sharp increase in the annual average E/F0–1 count by approximately 200 tornadoes was noted upon the implementation of NEXRAD Doppler weather radar in 1990–1991.[9][nb 5] 1974 marked the first year where significant tornado (E/F2+) counts became homogenous with contemporary values, attributed to the consistent implementation of Fujita scale assessments.[13][nb 3] Numerous discrepancies on the details of tornadoes in this outbreak exist between sources. The total count of tornadoes and ratings differs from various agencies accordingly. The list below documents information from the most contemporary official sources alongside assessments from tornado historian Thomas P. Grazulis.
Color / symbol | Description |
---|---|
† | Data from Grazulis 1990/1993/2001b |
¶ | Data from a local National Weather Service office |
※ | Data from the 1977 Storm Data publication |
‡ | Data from the NCEI database |
♯ | Maximum width of tornado |
± | Tornado was rated below F2 intensity by Grazulis but a specific rating is unavailable. |
F# | Location | County / Parish | State | Start Coord.[nb 6] | Date[nb 2] | Time (UTC) | Path length | Width[nb 7] | Damage |
---|---|---|---|---|---|---|---|---|---|
F1 | S of Florence※ | Rankin | Mississippi | 32°08′N 90°09′W / 32.13°N 90.15°W | April 4 | 12:00–? | 0.1 mi (0.16 km) | 50 yd (46 m) | <$1,000※ |
This tornado touched down along MS 469. A barn lost its tin roof and another incurred negligible damage.[17][18] | |||||||||
F2† | WNW of Center to NW of Preston※ | Neshoba, Kemper | Mississippi | 32°49′N 89°00′W / 32.82°N 89.00°W | April 4 | 14:00–? | 10 mi (16 km)※ | 100 yd (91 m) | $85,000※ |
This tornado dissipated a short distance north of MS 21. A few businesses, a pair of homes, and two trailers were wrecked, while outbuildings, barns, and an additional home were damaged.[19][20][21][22] | |||||||||
F2† | S of Macon to W of Prairie Point | Calhoun | Mississippi | 33°03′N 88°33′W / 33.05°N 88.55°W | April 4 | 15:00–? | 10 mi (16 km)※ | 500 yd (460 m)† | $25,000 |
This tornado struck the Elon settlement. A silo, a trailer, and a frame-built home were wrecked. Outbuildings on farms were damaged as well, and one person was injured slightly.[19][20][23] | |||||||||
F0 | Hannibal※ | Marion | Missouri | 39°40′N 91°20′W / 39.67°N 91.33°W | April 4 | 15:30–? | 0.2 mi (0.32 km) | 10 yd (9.1 m) | $2,500 |
A brief tornado partly unroofed a home and an adjacent carport. Nearby houses suffered minor damage, and several trees were downed.[24][20][25] | |||||||||
F2 | Near Hanceville to Center Hill※ | Cullman | Alabama | 34°04′N 86°46′W / 34.07°N 86.77°W | April 4 | 17:12–? | 5.9 mi (9.5 km)‡ | 200 yd (180 m) | $25,000 |
A pair of homes were badly damaged and a few trailers were destroyed. Numerous trees were splintered and prostrated as well. A trio of injuries occurred.[19][26][27] | |||||||||
F2 | S of Section to N of Dutton | Jackson | Alabama | 34°33′N 85°59′W / 34.55°N 85.98°W | April 4 | 18:20–? | 5 mi (8.0 km)† | 100 yd (91 m) | $250,000 |
A strong tornado impacted 20 agricultural outbuildings and homes. One person was injured.[19][26][28] | |||||||||
F2 | Southern Ragland | St. Clair | Alabama | 33°44′N 86°09′W / 33.73°N 86.15°W | April 4 | 18:30–? | 0.5 mi (0.80 km) | 20 yd (18 m) | $60,000† |
Five homes were severely damaged or destroyed.[19][26][29] | |||||||||
F1 | Elkton※ | Todd | Kentucky | 36°49′N 87°09′W / 36.82°N 87.15°W | April 4 | 19:30–?‡ | 0.8 mi (1.3 km)‡ | 200 yd (180 m) | $250,000 |
A farmhouse, four barns, and four trailers were destroyed. Airborne glass injured a small child.[30][31] | |||||||||
F2 | Eastern Springville | St. Clair | Alabama | 33°46′N 86°28′W / 33.77°N 86.47°W | April 4 | 20:00–? | 3.3 mi (5.3 km)‡ | 80 yd (73 m) | $85,000† |
21 barns and homes were destroyed or damaged.[19][26][32] | |||||||||
F2 | W of Markton to E of Southside | Etowah | Alabama | 33°53′N 86°01′W / 33.88°N 86.02°W | April 4 | 20:30–? | 5 mi (8.0 km)※ | 150 yd (140 m) | $250,000 |
A dozen homes were destroyed or severely damaged. Half a dozen trailers and 17 outbuildings were wrecked or otherwise damaged as well. Four people were injured.[19][26][33] | |||||||||
F2† | N of Ashville† to SE of Steele‡ | St. Clair | Alabama | 33°50′N 86°15′W / 33.83°N 86.25°W | April 4 | 20:30–? | 7.3 mi (11.7 km)‡ | 150 yd (140 m) | $140,000† |
1 death – Three trailers, seven barns, a house, and a small business were destroyed. A total of 16 other homes were damaged as well, a few of them severely. A woman was killed by a falling tree while refuging in an above-ground storm cellar.[19][26][34] | |||||||||
F5 | ESE of Forestdale to ESE of Pinson¶ | Jefferson | Alabama | 33°31′N 86°56′W / 33.52°N 86.93°W | April 4 | 21:00–? | 15 mi (24 km)※ | 1,320 yd (1,210 m)♯※ | $25,000,000¶ |
22 deaths – See section on this tornado | |||||||||
F3 | E of Cave Spring to ESE of Six Mile‡ to Lindale※ | Floyd | Georgia | 34°10′N 85°12′W / 34.17°N 85.20°W | April 4 | 21:15–? | 20 mi (32 km)※ | 400 yd (370 m) | $2,500,000 |
1 death – Major damage occurred in Lindale. A dozen trailers were destroyed and nine others were extensively damaged. 24 frame homes were badly damaged or wrecked. Three dairy farms sustained major damage, and four others sustained lesser damage. There were 15 injuries.[19][35][36] | |||||||||
F3† | Adairsville to Folsom | Bartow | Georgia | 34°22′N 84°56′W / 34.37°N 84.93°W | April 4 | 21:30–? | 6 mi (9.7 km)※ | 100 yd (91 m) | $250,000 |
Eight chicken coops, seven service buildings, three trailers, and three houses were destroyed. Multiple other structures were damaged.[19][35][37] | |||||||||
F1 | Ramhurst | Murray | Georgia | 34°42′N 84°44′W / 34.70°N 84.73°W | April 4 | 21:45–? | 2 mi (3.2 km) | 100 yd (91 m) | $250,000 |
10 service buildings, two chicken coops, two mobile homes, and a grist mill were destroyed. A few other houses were damaged.[35][38] | |||||||||
FU※ | S of Cincinnati | Boone, Kenton | Kentucky | Unknown | April 4 | 22:00–? | 12 mi (19 km) | 750 yd (690 m) | $250,000 |
This tornado produced scattered damage, occurring at four different spots. A few mobile homes, a pair of garages, nine homes, and 14 barns were destroyed or damaged.[30] | |||||||||
F1 | Edgewood | Madison | Indiana | 40°06′N 85°44′W / 40.10°N 85.73°W | April 4 | 23:00–? | 0.5 mi (0.80 km) | 20 yd (18 m) | $25,000 |
A house was unroofed and a shed and a garage wrecked.[30][39] | |||||||||
F2† | Mill Creek area※ | Lumpkin | Georgia | 34°30′N 83°57′W / 34.50°N 83.95°W | April 4 | 01:00–? | 5.2 mi (8.4 km)‡ | 400 yd (370 m) | $250,000 |
This tornado generated low-end F2 damage. 20 chicken coops were destroyed or damaged. Four homes received damage, and major tree damage occurred as well, with losses to the latter totaling $200,000. An injury was reported.[19][35][40] | |||||||||
F1 | S of Traphill to E of Thurmond※ | Wilkes | North Carolina | 36°19′N 81°01′W / 36.32°N 81.02°W | April 4 | 02:30–? | 10 mi (16 km)※ | 100 yd (91 m) | $250,000 |
The tornado skipped along its path. Trees, mobile homes, and chicken coops were damaged.[41][42] | |||||||||
F1 | Eastern Sparks to WNW of Chaserville | Cook | Georgia | 31°10′N 83°26′W / 31.17°N 83.43°W | April 5 | 07:45–? | 5.4 mi (8.7 km)‡ | 100 yd (91 m)※ | $25,000 |
A mobile home was destroyed and a few homes slightly damaged. There was also damage to agricultural implements, pecan trees, and outbuildings.[35][43] | |||||||||
F1 | Onancock※ | Accomack | Virginia | 37°43′N 75°45′W / 37.72°N 75.75°W | April 5 | 14:03–?※ | 2 mi (3.2 km) | 50 yd (46 m) | $250,000 |
Two chicken houses, a garage, and several small storage buildings were completely destroyed. A house lost its metal roof and a church lost its bell tower. Most other structural damage was limited to shingles or inflicted by fallen trees. About 15 trees were uprooted and more than 50 sustained minor damage.[44][45] | |||||||||
F2 | Swatara Township | Dauphin | Pennsylvania | 40°15′N 76°50′W / 40.25°N 76.83°W | April 5 | 21:50–22:15※ | 2 mi (3.2 km) | 67 yd (61 m) | $2,500,000 |
35 homes were destroyed or damaged. Debris from the homes clung to trees. A woman was injured when her trailer was overturned.[19][46][47] |
Birmingham–Smithfield, Alabama
[edit]F5 tornado | |
---|---|
on the Fujita scale | |
Overall effects | |
Fatalities | 22 |
Injuries | 130 |
Damage | $25 million ($125,700,000 in 2024 USD) |
Developing 4 mi (6.4 km) northwest of Birmingham, near US 78, this extremely violent tornado proceeded northeastward through northern Jefferson County. Near the point of touchdown, Daniel Payne College suffered extensive damage, forcing it to permanently close due to the extent of the destruction. Rapidly intensifying, it generated F5 damage in the neighborhood of Hayes Highland, particularly along and near a lane and drive each named Smithfield, from which the tornado derived its moniker. In this area, abutting the intersection of I-65 and US 31, hundreds of homes were completely destroyed, many of which were completely swept away, despite being well-built. Some of the homes built into hillsides even had their cinder-block basement walls swept away, and at least one home was reportedly annihilated, with even its foundation said to be missing. Many trees in the area were snapped and debarked and vehicles were thrown and destroyed. A pair of dump-trucks were thrown through the air as well. Ted Fujita followed the tornado and supercell from an airplane and while surveying damage; he rated the Smithfield tornado F5, but initially considered assigning a rating of F6. (He once rated the 1970 Lubbock and 1974 Xenia tornadoes as such, but his preliminary estimates were subsequently revised to the official ratings of F5.) The NCEI incorrectly list the path as extending from west of Birmingham to east-northeast of Tarrant.[48]
Non-tornadic impacts
[edit]The storms that brought the tornadoes on April 4 also brought a large squall line across Alabama. This proved disastrous when Southern Airways Flight 242 attempted to fly around the storm and instead flew straight into it. Massive amounts of very large hail and very heavy rain battered the plane and destroyed its engines. With no way to keep flying, it attempted a landing on a stretch of highway in New Hope, Georgia. The road section used for the forced landing, formerly called Georgia State Route 92 Spur, is now called Dallas–Acworth Highway (formerly Georgia State Route 381). The DC-9 actually landed successfully, but then crashed into a gas station, grocery store, and other structures and vehicles during the rollout. The plane was destroyed, killing the flight crew, 60 passengers, and nine people on the ground.[49]
Aftermath, recovery, and records
[edit]The F5 tornado touched down near the end of the path of three other violent tornadoes that struck the Birmingham region in 1956, 1998, and 2011. The 1956 tornado was an F4 that struck McDonald Chapel and continued through Edgewater, northern Birmingham, Fultondale, and Tarrant before dissipating, killing 25. In 1998, an F5 tornado touched town in a rural area near Tuscaloosa before impacting Rock Creek, Sylvan Springs, Edgewater and McDonald Chapel, killing 32. The 2011 tornado was an EF4 that devastated Tuscaloosa and then struck Concord, Pleasant Grove, McDonald Chapel, northern Birmingham, and Fultondale before lifting, killing 64.[50]
See also
[edit]- List of F5 and EF5 tornadoes
- April 1998 Birmingham tornado
- List of North American tornadoes and tornado outbreaks
- Southern Airways Flight 242
Notes
[edit]- ^ An outbreak is generally defined as a group of at least six tornadoes (the number sometimes varies slightly according to local climatology) with no more than a six-hour gap between individual tornadoes. An outbreak sequence, prior to (after) the start of modern records in 1950, is defined as a period of no more than two (one) consecutive days without at least one significant (F2 or stronger) tornado.[1]
- ^ a b All dates are based on the local time zone where the tornado touched down; however, all times are in Coordinated Universal Time and dates are split at midnight CST/CDT for consistency.
- ^ a b The Fujita scale was devised under the aegis of scientist T. Theodore Fujita in the early 1970s. Prior to the advent of the scale in 1971, tornadoes in the United States were officially unrated.[2][3] Tornado ratings were retroactively applied to events prior to the formal adoption of the F-scale by the National Weather Service.[4] While the Fujita scale has been superseded by the Enhanced Fujita scale in the U.S. since February 1, 2007,[5] Canada used the old scale until April 1, 2013;[6] nations elsewhere, like the United Kingdom, apply other classifications such as the TORRO scale.[7]
- ^ The National Oceanic and Atmospheric Administration's Storm Data publication does not list exact damage totals for every event, instead giving damage categories. As such, damage for individual tornadoes is not comprehensive.
- ^ Historically, the number of tornadoes globally and in the United States was and is likely underrepresented: research by Grazulis on annual tornado activity suggests that, as of 2001, only 53% of yearly U.S. tornadoes were officially recorded. Documentation of tornadoes outside the United States was historically less exhaustive, owing to the lack of monitors in many nations and, in some cases, to internal political controls on public information.[10] Most countries only recorded tornadoes that produced severe damage or loss of life.[11] Significant low biases in U.S. tornado counts likely occurred through the early 1990s, when advanced NEXRAD was first installed and the National Weather Service began comprehensively verifying tornado occurrences.[12]
- ^ All starting coordinates are based on the NCEI database and may not reflect contemporary analyses
- ^ The listed width values are primarily the average/mean width of the tornadoes, with those having known maximum widths denoted by ♯. From 1952 to 1994, reports largely list mean width whereas contemporary years list maximum width.[14] Values provided by Grazulis are the average width, with estimates being rounded down (i.e. 0.5 mi (0.80 km) is rounded down from 880 yards to 800 yards.[15][16]
References
[edit]- ^ Schneider, Russell S.; Brooks, Harold E.; Schaefer, Joseph T. (2004). Tornado Outbreak Day Sequences: Historic Events and Climatology (1875–2003) (PDF). 22nd Conf. Severe Local Storms. Hyannis, Massachusetts: American Meteorological Society. Retrieved September 17, 2019.
- ^ Grazulis 1993, p. 141.
- ^ Grazulis 2001a, p. 131.
- ^ Edwards et al. 2013, p. 641–642.
- ^ Edwards, Roger (March 5, 2015). "Enhanced F Scale for Tornado Damage". The Online Tornado FAQ (by Roger Edwards, SPC). Storm Prediction Center. Retrieved February 25, 2016.
- ^ "Enhanced Fujita Scale (EF-Scale)". Environment and Climate Change Canada. Environment and Climate Change Canada. June 6, 2013. Archived from the original on March 3, 2016. Retrieved February 25, 2016.
- ^ "The International Tornado Intensity Scale". Tornado and Storm Research Organisation. Tornado and Storm Research Organisation. 2016. Archived from the original on March 5, 2016. Retrieved February 25, 2016.
- ^ Tornado reported between 04/04/1977 and 04/05/1977 (2 days). Storm Events Database (Report). NOAA. Retrieved 4 December 2023 – via National Centers for Environmental Information.
- ^ Agee and Childs 2014, p. 1496.
- ^ Grazulis 2001a, pp. 251–4.
- ^ Edwards, Roger (March 5, 2015). "The Online Tornado FAQ (by Roger Edwards, SPC)". Storm Prediction Center: Frequently Asked Questions about Tornadoes. Storm Prediction Center. Retrieved February 25, 2016.
- ^ Cook & Schaefer 2008, p. 3135.
- ^ Agee and Childs 2014, pp. 1497, 1503.
- ^ Agee and Childs 2014, p. 1494.
- ^ Brooks 2004, p. 310.
- ^ Grazulis 1990, p. ix.
- ^ Storm Data 1977, p. 5.
- ^ Storm Data Publication 1977, #10050008
- ^ a b c d e f g h i j k l Grazulis 1993, p. 1192.
- ^ a b c Storm Data 1977, p. 6.
- ^ Storm Data Publication 1977, #10050009
- ^ Storm Data Publication 1977, #10050010
- ^ Storm Data Publication 1977, #10050011
- ^ "Severe Weather Database Files (1950-2021)". Storm Prediction Center Maps, Graphics, and Data Page. Norman, Oklahoma: Storm Prediction Center. July 11, 2021. Retrieved 24 February 2022.
- ^ Storm Data Publication 1977, #10059535
- ^ a b c d e f Storm Data 1977, p. 2.
- ^ Storm Data Publication 1977, #9976465
- ^ Storm Data Publication 1977, #9976467
- ^ Storm Data Publication 1977, #9976468
- ^ a b c Storm Data 1977, p. 4.
- ^ Storm Data Publication 1977, #10033923
- ^ Storm Data Publication 1977, #9976470
- ^ Storm Data Publication 1977, #9976471
- ^ Storm Data Publication 1977, #9976472
- ^ a b c d e Storm Data 1977, p. 3.
- ^ Storm Data Publication 1977, #9995222
- ^ Storm Data Publication 1977, #9995224
- ^ Storm Data Publication 1977, #9995225
- ^ Storm Data Publication 1977, #10016135
- ^ Storm Data Publication 1977, #9995229
- ^ Storm Data 1977, p. 7.
- ^ Storm Data Publication 1977, #10091000
- ^ Storm Data Publication 1977, #9995230
- ^ Storm Data 1977, p. 12.
- ^ Storm Data Publication 1977, #10151506
- ^ Storm Data 1977, p. 8.
- ^ Storm Data Publication 1977, #10117988
- ^ Multiple sources:
- Edwards, Roger, ed. (March 19, 2021). "F5 and EF5 Tornadoes of the United States, 1950-present". The Online Tornado FAQ: Frequently Asked Questions about Tornadoes. Norman, Oklahoma: Storm Prediction Center. Retrieved 3 February 2022.
- Grazulis 1984, p. A-92
- Grazulis 1993, p. 1192
- Grazulis 2001b, p. 28
- Grazulis, Thomas P.; Grazulis, Doris, eds. (1998). "Other Disastrous Birmingham Area Tornadoes". St. Johnsbury, Vermont: The Tornado Project of Environmental Films. Archived from the original on 3 June 2011. Retrieved 4 December 2023.
- "Smithfield Tornado 4/4/1977". NWS Birmingham, Alabama Weather Forecast Office. Calera, Alabama: National Weather Service. Retrieved 4 December 2023.
- Storm Data 1977, p. 2
- Storm Data Publication 1977, #9976475
- ^ Ayres, Jr., B. Drummond (April 6, 1977). "Hail in Engines Is Blamed in Georgia Crash Killing 68". The New York Times. p. 20.
- ^ Grazulis, Thomas P.; Grazulis, Doris, eds. (1998). "Other Disastrous Birmingham Area Tornadoes". St. Johnsbury, Vermont: The Tornado Project of Environmental Films. Archived from the original on 3 June 2011. Retrieved 4 December 2023.
Sources
[edit]- Agee, Ernest M.; Childs, Samuel (June 1, 2014). "Adjustments in Tornado Counts, F-Scale Intensity, and Path Width for Assessing Significant Tornado Destruction". Journal of Applied Meteorology and Climatology. 53 (6). American Meteorological Society: 1494–1505. doi:10.1175/JAMC-D-13-0235.1.
- Brooks, Harold E. (April 2004). "On the Relationship of Tornado Path Length and Width to Intensity". Weather and Forecasting. 19 (2): 310–19. Bibcode:2004WtFor..19..310B. doi:10.1175/1520-0434(2004)019<0310:OTROTP>2.0.CO;2.
- Cook, A. R.; Schaefer, J. T. (August 2008). "The Relation of El Niño–Southern Oscillation (ENSO) to Winter Tornado Outbreaks". Monthly Weather Review. 136 (8): 3121–3137. Bibcode:2008MWRv..136.3121C. doi:10.1175/2007MWR2171.1.
- Edwards, Roger; LaDue, James G.; Ferree, John T.; Scharfenberg, Kevin; Maier, Chris; Coulbourne, William L. (May 1, 2013). "Tornado Intensity Estimation: Past, Present, and Future". Bulletin of the American Meteorological Society. 94 (5). American Meteorological Society: 641–653. doi:10.1175/BAMS-D-11-00006.1.
- Grazulis, Thomas P. (May 1984). Violent Tornado Climatography, 1880–1982. OSTI (Technical report). NUREG. Washington, D.C.: Nuclear Regulatory Commission. OSTI 7099491. CR-3670.
- — (November 1990). Significant Tornadoes 1880–1989. Vol. 2. St. Johnsbury, Vermont: The Tornado Project of Environmental Films. ISBN 1-879362-02-3.
- — (July 1993). Significant Tornadoes 1680–1991: A Chronology and Analysis of Events. St. Johnsbury, Vermont: The Tornado Project of Environmental Films. ISBN 1-879362-03-1.
- — (2001a). The Tornado: Nature's Ultimate Windstorm. Norman: University of Oklahoma Press. ISBN 978-0-8061-3538-0.
- — (2001b). F5-F6 Tornadoes. St. Johnsbury, Vermont: The Tornado Project of Environmental Films.
- National Weather Service (April 1977). "Storm Data and Unusual Weather Phenomena". Storm Data. 19 (4). Asheville, North Carolina: National Climatic Data Center.
- National Weather Service (April 1977). Storm Data Publication (Report). National Centers for Environmental Information – via Storm Events Database.