1998 Comfrey – St. Peter tornado outbreak

Infobox tornado outbreak|name=1998 Comfrey – St. Peter tornado outbreak
date=March 29, 1998
image location=Csptornado2.jpg


duration=4 hours
fujitascale=F4
tornadoes=16
total damages (USD)=$235 million
total fatalities=2
areas affected=southern Minnesota, WisconsinThe 1998 Comfrey – St. Peter tornado outbreak was an unseasonably-strong tornado outbreak which affected southern Minnesota and Wisconsin in the United States on March 29, 1998. A strong area of low pressure combined with a warm front and favorable upper-level dynamics combined to produce 16 tornadoes; 14 in Minnesota and two in Wisconsin. Thirteen of the tornadoes were caused by one parent supercell, which traveled approximately convert|150|mi|km|0 across southern Minnesota during the afternoon hours. Most of the destruction was caused by an F4 tornado that hit the town of Comfrey, Minnesota, an F3 tornado that hit St. Peter, Minnesota, and an F2 tornado that hit Le Center, Minnesota. Over $235 million in damages was recorded, two people were killed, and 36 others were injured. Gustavus Adolphus College in St. Peter was especially hard-hit, with several buildings damaged or destroyed, 2,000 trees lost, and nearly 80% of the windows on the campus shattered. In Comfrey, 75% of the structures in the town were damaged or destroyed, including the school. Seven counties in southern Minnesota were declared federal disaster areas.

The outbreak broke many early-season tornado records for the state of Minnesota. The 14 tornadoes were the most to ever touch down in one day during the month of March, the F4 tornado was the strongest ever recorded in March, and its 67-mile (108 km) path is the longest continuous-track tornado recorded in Minnesota during any month. The following December, the United States Department of Commerce awarded a bronze medal to the Twin Cities office of the National Weather Service for providing excellent service to the public during the event. The outbreak was named the top severe weather event in Minnesota during the 1990s by Metro Skywarn, the Twin Cities branch of the Skywarn weather spotter network.

Meteorological synopsis

s into the middle 60s °F (18 °C). Winds on the surface were from the southeast, which helped to enhance the potential for tornadoes.cite paper | first = Amanda | last = Wood | title = Mesoscale Supercell Dynamics of the Comfrey/St. Peter Tornado Outbreak March 29, 1998 | publisher = University of Wisconsin | year = 2006 | url = http://www.aos.wisc.edu/uwaosjournal/Volume1/AOS453/FCS_Wood.pdf | format = PDF | accessdate = 2008-06-14]

By early afternoon, the low-pressure area had moved east into Nebraska, and the warm front had pushed northward into southern Minnesota. The atmosphere to the south of the warm front was strongly capped, meaning that the best chance of thunderstorm development was in areas along and slightly north of it.cite web | title = The National Weather Service Perspective | work = The Southern Minnesota Tornadoes of March 29, 1998 | publisher = NWS – Twin Cities | date = April 20, 2008 | url = http://www.crh.noaa.gov/mpx/?n=1998mar29nwsstories | accessdate = 2008-05-08] By the time the thunderstorms started developing CAPE values were 2000 J/kg, indicating moderate atmospheric instability.cite web
title = CAPE for INSTABILITY DESCRIPTORS | publisher = Storm Prediction Center | url = http://www.spc.noaa.gov/misc/tables/capetext.htm | accessdate = 2008-08-04] Low-level and deep-layer shear values of convert|44|kn|km/h and convert|87|kn|km/h were present over the same areas. The strong upper-level jet, CAPE and shear values combined to create very favorable conditions for the development of severe thunderstorms and tornadoes.

Forecasts

Weather forecasters first began to notice the severity of impending weather situation after the 6:00 pm CST (0000 UTC) computer model runs on the night of Friday, March 27. On Saturday, March 28 at 11:30 am the Storm Prediction Center issued a Day 2 moderate risk of severe weather for southeast Minnesota, northeast Iowa, northwest Illinois and much of Wisconsin.cite web | title = What National Weather Service Forecasts and Warnings Were Issued? | work = The Southern Minnesota Tornadoes of March 29, 1998 | publisher = NWS – Twin Cities | date = March 6, 2008 | url = http://www.crh.noaa.gov/mpx/?n=1998mar29forecasts | accessdate = 2008-05-08] Later model runs on March 28 only increased forecasters confidence that a major severe weather event would occur the following day.

Early on Sunday March 29, forecasters at the Twin Cities NWS noticed that due to the models prediction of strong wind shear and instability, the tornado risk was quite high for their region. Area forecast discussions during the early-morning hours mentioned the possibility of F3-strength tornadoes later in the day. Also on the morning of March 29, the Storm Prediction Center issued a Day 1 moderate risk of severe weather. This moderate risk area was more narrow than the previous days outlook, encompassing only southwest Wisconsin, northern Iowa and the southern third of Minnesota.

As the day moved on, the Twin Cities, Sioux Falls and La Crosse NWS forecast offices all saw the potential for "strong to violent" tornadoes, and used such verbiage in their forecasts. The Twin Cities NWS noted in their 12:26 pm forecast discussion that "thunderstorms located south of a Redwood Falls to Minneapolis to Rice Lake line could be particularly strong with the potential of tornadic thunderstorms". Just before 12:00 pm, the Storm Prediction Center issued a mesoscale discussion stating that "Given strength of vertical shear profiles, CAPE on the order of 2000 J/kg will support increasing potential for tornadic supercells during the afternoon hours, especially along an axis roughly from Yankton through Sioux Falls into Redwood Falls and Minneapolis/Rochester areas. We will continue to monitor. Present indications are WW (Weather Watch) will be necessary within the next 2 to 3 hours." At 1:35 pm the Storm Prediction Center issued tornado watch #132 with a particularly dangerous situation designation. The watch area encompassed most of southern Minnesota and northern Iowa, along with small parts of northeast Nebraska, southeast South Dakota, southwest Wisconsin, and was made in effect from 2:00 pm – 8:00 pm.

Outbreak description

The thunderstorms that would eventually go on to spawn the tornadoes began forming in southeastern South Dakota around 2:00 pm. The first severe weather report of the outbreak was of convert|3/4|in|mm|0 diameter hail two miles (3 km) south of Brandon, South Dakota.cite web | title = Event Record Details – Brandon hail | publisher = National Climatic Data Center (NCDC) | date = March 29, 1998 | url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~339866 | accessdate = 2008-03-10] Shortly thereafter the thunderstorms moved east across the border into Minnesota. After several more reports of severe hail with the growing thunderstorms, [cite web | title = Event Record Details – Hardwick hail | publisher = NCDC | date = March 29, 1998 | url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325571 | accessdate = 2008-03-29] [cite web | title = Event Record Details – Edgerton hail | publisher = NCDC | date = March 29, 1998 | url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325573 | accessdate = 2008-03-29] the first tornado of the day—rated F2 on the Fujita scale—touched down at 3:23 pm two miles (3 km) north of Lismore.cite web| title = Event Record Details – Lismore tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325578| accessdate = 2008-07-29] It was on the ground for less than a mile (1.6 km) and caused minor damage. Five more tornadoes (all rated F2 or lower) briefly touched down during the next hour in the same general area; none of which inflicted major damage. All of these tornadoes were spawned by the same supercell thunderstorm. During the remainder of the afternoon hours, this supercell would proceed to track east-northeast across southern Minnesota for convert|150|mi|km|0, tracking slightly north of the warm front.cite web | title = Five Year Anniversary of the Comfrey/ St. Peter Tornado Outbreak | publisher = NWS – Twin Cities | date = March 26, 2003 | url = http://climate.umn.edu/doc/journal/comfrey_tornado_five_year.htm | accessdate = 2006-12-22 ]

Comfrey

At 3:50 pm a tornado touched down 7 miles (11 km) east of Avoca, Minnesota in eastern Murray county.cite web| title = Event Record Details – Avaca tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325591| accessdate = 2008-05-15] As the tornado moved through Cottonwood county, it grew to a width of convert|900|yd|m|0 and obtained F3 strength.cite web| title = Event Record Details – Westbrook tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325593| accessdate = 2008-05-15] It destroyed numerous farms, farm equipment, trees, power lines and poles, vehicles, and other structures in its path in Cottonwood County. Twenty people outside a church near Jeffers were able to get inside the church just before the tornado hit, and as a result nobody suffered serious injuries.cite web | title = What Happened? | work = The Southern Minnesota Tornadoes of March 29, 1998 | publisher = NWS – Twin Cities | date = March 6, 2008 | url = http://www.crh.noaa.gov/mpx/?n=1998mar29intro | accessdate = 2008-03-13]

press | year = 2006 | id = ISBN 0–87351–554–4]

As the tornado continued to move through Brown County it achieved F4 strength and grew to convert|1.25|mi|km|0 wide. Approximately 15% of the 1000 farms in Brown County sustained damage from the tornado, [cite news | last = Steil | first = Mark | title = Tornado Anniversary | publisher = Minnesota Public Radio | date = March 29, 1999 | url = http://news.minnesota.publicradio.org/features/199903/29_steilm_tornado-m/ | accessdate = 2008-07-25] and 500 dairy cattle were lost. Northwest of Hanska a man was killed when the tornado caused his house to collapse. The tornado went on to cause additional damage in Blue Earth and Watonwan counties. After traveling across six counties for 1 hour and 25 minutes and causing $75 million in damage, the twister lifted back into the clouds at 5:15 pm four miles (6 km) southeast of Courtland.cite web| title = Event Record Details – Courtland tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325615| accessdate = 2008-05-15] In addition to the one fatality, 19 people were injured by this tornado.

t. Peter

. As the tornado moved to the east, a six year-old boy was killed when the vehicle his family was riding in was overtaken by the tornado. At 5:30 pm the F3 tornado hit St. Peter, a town of about 10,000 people located in eastern Nicollet County, and inflicted severe damage on much of the town. [cite web | title = Twisters kill two in southern Minnesota | publisher = Associated Press | date = March 14, 2000 | url = http://www.usatoday.com/weather/tornado/wtor329.htm | accessdate = 2006-12-22 ] Gustavus Adolphus College, which sits on top of a hill on the west side of St. Peter, sustained heavy damage after taking a direct hit from the twister. Eighty percent of the windows on the campus were shattered, and most of the major buildings on campus sustained damaged.cite web | last = Thomas | first = Matt | title = Gustavus to Commemorate Tenth Anniversary of 1998 Tornado | publisher = Gustavus Media Relations | date = February 29, 2008 | url = http://gustavus.edu/news/3755 | accessdate = 2008-05-15] The chapel spire—a campus landmark—was snapped in half. The admissions office was destroyed, as was Johnson Hall, a small dormitory.cite web | last = Garrison | first = Luke | title = Detestation and Renewal | publisher = The Gustavian Weekly | date = March 14, 2008 | url = http://weekly.blog.gustavus.edu/2008/03/14/devastation-and-renewal/ | accessdate = 2008-05-15] The Lund Center for Physical Education and Health lost part of its roof, as did the tennis center. The football press box was blown from the top of the stadium bleachers, and the the baseball dugouts were damaged. [cite news | last = Meryhew | first = Rochard | coauthors = Anthony Longtree | title = Gustavus Adolphus College loses a landmark; Storm's toppling of steeple strips campus of its `heart and soul' | publisher = Minneapolis Star Tribune | date = March 31, 1998 | accessdate = 2008-08-05] The tornado also uprooted more than 1000 trees, almost completely denuding the campus. Gustavus was on spring break at the time the tornado hit, so the campus was virtually vacant of students and there were no serious injuries or fatalities reported.

As the tornado continued through St. Peter it caused more damage and destruction. St. Peter's Catholic Church and St. Peter Evangelical Lutheran Church were destroyed, as was Arts and Heritage Center.cite news | last = Meryhew | first = Richard | coauthors = Robert Franklin | title = SIX MONTHS AFTER; Tornado-torn towns still trying to pick up the pieces | publisher = Minneapolis Star Tribune | date = September 29, 1998 | accessdate = 2008-08-05] The hospital was severely damaged and the library was hit and lost 25% of their books.cite web| title = Event Record Details – Nicollet tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325616| accessdate = 2008-05-15] Officials estimated 500 homes in St. Peter were destroyed, 1700 more were damaged and over 17,000 trees were lost. Many of the homes and trees that were destroyed in St. Peter were more than a century old. Debris from St. Peter that was sucked into the tornado fell back down to earth as far as Rice Lake, Wisconsin, over convert|130|mi|km|0 away. In addition to the damage in St. Peter, the tornado also damaged or destroyed 60 homes and caused $6.5 million in damage in rural areas. All together this tornado was on the ground for convert|18|mi|km|0 and inflicted $120 million in damage.

Le Center

.

Other tornadoes

Over the next hour the supercell continued to track across southern Minnesota, dropping four more tornadoes in Rice and Dakota counties. One of these tornadoes hit the town of Lonsdale at F2 strength, damaging four homes and six business in the town, and then 20 farms to the east of town. This tornado had a path of five miles (8 km) and caused $20 million in damage.cite web| title = Event Record Details – Lonsdale tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325621| accessdate = 2008-05-15] The last of the 13 tornadoes spawned by this supercell was a brief F0 that touched down five miles (8 km) southwest of Hastings,cite web| title = Event Record Details – Hastings tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325626| accessdate = 2008-05-15] and the supercell dissipated a few minutes later as it moved into Wisconsin.

Four additional tornadoes touched down this day. A tornado that was associated with the main supercell touched down briefly near Fulda, Minnesota at 3:55 pm, while the Comfrey tornado was also on the ground. It was rated as an F1 and caused minor damage. Three other tornadoes that were all unrelated to the main supercell were confirmed as well; one in southeast Minnesota near Wabasha and two in Wisconsin. All three were rated F0 on the Fujita Scale and produced only minor damage.cite web| title = Event Record Details – Wabasha tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~325614| accessdate = 2008-05-15] cite web| title = Event Record Details – Maxville tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~346518| accessdate = 2008-05-15] cite web| title = Event Record Details – Tomahawk tornado| publisher = NCDC| date = March 29, 1998| url = http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~346530| accessdate = 2008-05-15]

Confirmed tornadoes

Aftermath

date = April 1, 1998 | url = http://www.fema.gov/news/eventcounties.fema?id=533 | accessdate = 2008-05-23] The money allotted from the federal government allowed the affected towns to cleanup the damage and begin the rebuilding process. In addition, the state of Minnesota contributed $27.6 million to the cleanup and rebuilding effort, [cite news | author = Associated Press | title = Legislature quick with tornado relief | publisher = Minnesota Daily
date = April 7, 1998 | url = http://www.mndaily.com/daily/1998/04/07/world_nation/wn1.ap/ | accessdate = 2008-07-24] with $1.35 million designated specifically for the preservation of the historical buildings in St. Peter.cite news | last = Mack | first = Linda | title = A positive spin: St. Peter rebounds from '98 tornado; A huge storm brought tragedy - but also opportunity. | publisher = Minneapolis Star Tribune | date = May 7, 2003 | accessdate = 2008-08-05] cite news | last = Millett | first = Larry | title = Restoration of historic buildings 'remarkable' | publisher = St. Paul Pioneer Press | date = March 26, 1999 | url = http://www.hsem.state.mn.us/uploadedfile/recovery_handbook/Chapter13/Toolkit/Restoration.pdf | accessdate = 2008-06-14] Most of St. Peter's buildings that were on the National Historic Register were damaged, but only one—a French Second Empire school building built in 1871—had to be demolished. [cite news | last = Franklin | first = Robert | title = St. Peter Rebuilds: Putting history back together | publisher = Minneapolis Star Tribune | date = March 29, 1999 | accessdate = 2008-08-05] Three years after the tornado, the City of St. Peter reported that its population had grown by 2%, an unusual feat for a town that had so recently endured a natural disaster.cite news | last = Galbally | first = Erin | title = St. Peter Grows Despite Tornado | publisher = Minnesota Public Radio | date = March 29, 2001 | url = http://news.minnesota.publicradio.org/features/200103/28_newsroom_census/stpeter.shtml | accessdate = 2008-03-14]

At Gustavus, damage at the campus was estimated at nearly $60 million. Despite 33 of the 78 of the classrooms not being ready for use, the college re-opened three weeks after the tornado. [cite news | last = Lonetree | first = Anthony | title = A new campus landscape; Classes resume today at Gustavus Adolphus | publisher = Minneapolis Star Tribune | date = April 21, 1998 | accessdate = 2008-08-05] Following the storm, a major concern for the college was that the student base would be eroded. To prevent that from happening, every returning and graduating student was given a $3,000 check by the college. In addition, the school sent out letters and made phone calls to all 2,000 applicants within 10 days of the disaster. The 735 new students who reported to Gustavus the following fall comprised the largest incoming class in the school's history. After a summer of repairs, the symbolic end of the rebuilding occurred on October 22, 1998 when a new 175-foot (53 m) spire was placed atop the chapel.cite news | last = Lonetree | first = Anthony | title = Inspiring recovery; Gustavus Adolphus College today celebrates the return of an important spiritual landmark - the spire atop Christ Chapel. | publisher = Minneapolis Star Tribune | date = October 22, 1998 | accessdate = 2008-08-05]

After the tornado hit Comfrey, residents were forced to temporarily evacuate the town due to several gas leaks,cite news | title = Twisters kill two in southern Minnesota | publisher = Associated Press | date = March 14, 2000 | url = http://www.usatoday.com/weather/tornado/wtor329.htm | accessdate = 2008-05-15] and the Minnesota National Guard was called in to help secure the area. As a result of the K–12 school being destroyed, students resumed classes two weeks later convert|20|mi|km|0 to the north in Sanborn. To help stock their classrooms, the school used equipment and supplies that had been salvaged from the damage as well as items that had been donated. Since many Comfrey residents were displaced to nearby towns, school buses from Comfrey drove to each of these towns to provide transportation to the school in Sanborn.cite news | last = Steil | first = Mark | title = Nearby Schools Welcome Comfrey Students | publisher = Minnesota Public Radio | date = April 13, 1998 | url = http://news.minnesota.publicradio.org/features/199804/13_steilm_students-m/ | accessdate = 2008-03-14] After the tornado in Comfrey there were questions on whether or not the town would survive at all; the future of the town seemed to hinge the rebuilding of the school.cite news | last = Steil | first = Mark | title = Will Comfrey Save Its Tornado-Damaged School? | publisher = Minnesota Public Radio | date = April 3, 1998 | url = http://news.minnesota.publicradio.org/features/199804/03_steilm_school-m/ | accessdate = 2008-07-24] In the week after the tornado it was decided that the school would rebuild, and most of the town's businesses followed suit.cite news | last = Steil | first = Mark | title = Construction Drives Comfrey Comeback
publisher = Minnesota Public Radio | date = November 20, 1998 | url = http://news.minnesota.publicradio.org/features/199811/20_steilm_comfrey-m/ | accessdate = 2008-07-24] Ground was broken on the new school early the next year, and it opened to students on October 4, 1999. [cite news | last = Meryhew | first = Richard | title = New school brings fresh start | publisher = Minneapolis Star Tribune | date = October 3, 1999 | accessdate = 2008-08-05] The population of Comfrey is down to 367 from the 425 it was when the tornado hit.cite news | last = Stachura | first = Sea | title = Ten years after devastating tornadoes, communities thriving | publisher = Minnesota Public Radio | date = March 28, 2008 | url = http://minnesota.publicradio.org/display/web/2008/03/27/tornadoanniv/ | accessdate = 2008-05-15]

In total, the tornadoes officially caused $235 million in damage, [cite web | title = US tornadoes from 1950-2007 | publisher = Tornado History Project | date = March 29, 1998 | url =http://www.tornadohistoryproject.com/tornado.php?yr=1998&mo=3&day=29&st=%25&fu=%25&co=Any&l=auto&submit=Table&ddat=on&dsta=on&dcou=on&ddam=on&format=basic&p=1&s=1 | accessdate = 2008-07-24] although later estimates put damage at over $300 million in St. Peter alone. Additionally, over $800,000 in hail and downburst damage was reported over South Dakota, Minnesota and Wisconsin.

For the 13 tornadoes that touched down from the parent supercell in southern Minnesota, the Twin Cities and Sioux Falls NWS offices issued tornado warnings an average of 15 minutes before the warned areas were hit. Because of above average warning lead time, [cite book | last = Douglas | first = Paul | authorlink =Paul Douglas (meteorologist) | title = Restless Skies | publisher = Barnes & Noble Publishing | year = 2004 | pages = 84 | isbn = 0–7607–6133–2] and for excellence in forecasting the entire event, the United States Department of Commerce issued a bronze medal to the Twin Cities office the following December.

Historical perspective

on March 18, 1968.cite book | last = Lynch | first = Mike | title = Mike Lynch's Minnesota Weather Watch | publisher = Voyageur Press | year = 2007 | pages = 40 | isbn = 13: 978–0–7603–2863–7]

With a path of convert|67|mi|km|0, the Comfrey tornado was the fifth longest track tornado on record in Minnesota history.cite web | title = How Historically Unusual Was This? | work = The Southern Minnesota Tornadoes of March 29, 1998 | publisher = NWS – Twin Cities | date = March 6, 2008 | url = http://www.crh.noaa.gov/mpx/?n=1998mar29historical | accessdate = 2008-05-08] It is however the longest "continuous"-track tornado in Minnesota history, meaning that it was the longest to have been observed to always be in contact with the ground. The Comfrey F4 tornado is also the strongest tornado ever measured in Minnesota during the month of March. The previous strongest were two F3 tornadoes that occurred on March 27, 1905 and March 26, 1921.

Due to the magnitude of this event along with the time of the year that it took place, the Comfrey – St. Peter tornado outbreak was named the top Minnesota severe weather event of the 1990s by Metro Skywarn, an organization that works with the National Weather Service to coordinate Skywarn storm spotters in Minnesota.cite web | last = Johnson | first = Dave | title = Top 10 Minnesota Severe Weather Events 1990-1999 | publisher = Metro Skywarn | date = June 30, 2006 | url = http://www.skywarn.ampr.org/mn_top10.html | accessdate = 2006-12-22 ]

ee also

*Climate of Minnesota
*List of Minnesota weather records
*2006 Dakota–Minnesota tornado outbreak
*List of North American tornadoes and tornado outbreaks

References

External links

* [http://www.crh.noaa.gov/mpx/?n=1998Mar29 The Southern Minnesota Tornadoes of March 29, 1998]
* [http://www.crh.noaa.gov/fsd/science/tor980329/index.php Southwest Minnesota Tornadoes March 29, 1998]
* [http://www.crh.noaa.gov/images/mpx/1998Mar29/kmpx_overview_reflectivity_animation.gifRegional radar animation]
* [http://gustavus.edu/events/tornado/ Photos of Gustavus damage]
* [http://www.aos.wisc.edu/uwaosjournal/Volume1/AOS453/FCS_Wood.pdf Mesoscale Supercell Dynamics]
* [http://cimss.ssec.wisc.edu/goes/misc/980329_spclog.text Severe weather reports - March 29, 1998]