SKY SCOOP

The Great Flood Of 1997

During the first 10 days of March, portions of southern Ohio and Northern Kentucky received the worst river floodingin the past 33 years. For people living along the Licking river especially in Falmouth and Butler Kentucky as well asthe Ohio Brush Creek in West Union Ohio, the river levels rose above or near the flood of record. The Ohio BrushCreek at West Union crested at approximately 31 feet which is only 2 feet below the flood of record. For the Lickingriver at Falmouth however, the estimated crest was between 50 and 51 feet. The previous flood of record for thislocation was 47.1 feet, over 3 feet below the 1997 crest.

The flash flooding began around 8 AM on Saturday March 1st. By that evening though, virtually all of Falmouthand Butler KY had been evacuated. Unfortunately by the end of the event, nearly 80 percent of the homes andbusinesses in Falmouth were destroyed or had sustained major damage. Also, 5 people were killed in the Falmoutharea, all because they attempted to return to their home after being evacuated. A total of 13 deaths occurred inWilmington's county warning area due to flooding and flash flooding.

You, as spotters, performed excellently in reporting rainfall and flooding information to Wilmington throughoutthe event. As many people probably already know, an estimated amount of over 10 inches of rain fell across 7 countiesin both Ohio and Kentucky during a 36 hour period. This excessive amount of rainfall is a very rare occurrence;consequently, your rainfall reports were especially helpful in trying to calibrate the radar precipitation estimates. Withoutyour reports to verify the radar estimates, it may have been difficult for us to believe the severity of the event. Onespotter in particular, Brenda Booher informed us that 5.2 inches of rain had fallen in Falmouth between 11 PM February28th and noon on March 1st. Another spotter in Brown county Ohio also assisted greatly by informing us that 5 inchesof rain had fallen near Ripley by noon on March 1st.

The information we received about the flooding was also quite helpful in the issuance of the flash flood and floodwarnings. Spotters from Robertson, Pendleton, and Grant Counties in Kentucky as well as in Brown and AdamsCounties in Ohio all indicated that extensive flooding occurred along creeks and streams throughout the day onSaturday, March 1st. The spotters in Adams and Grant Counties also informed us of the numerous evacuations in theirareas. With this information, we were better able to describe the extent of the flooding in the warnings and floodstatements.

Without your dedication and assistance during the flood of '97, the devastation and destruction would have beenmuch more extensive and deadly.

Wilmington Ohio Pager System

For the past two years, the Wilmington office has offered to Emergency Management Officials as well as members offire and police departments a weather pager service. However, we are now able to expand this service to the membersof the Skywarn organization.

The purpose of this system is to be a secondary means of receiving warning or watch information. Presently,we are able to offer these services through Pagenet and USA Mobile. Both Pagenet and USA Mobile have agreed tooffer the pager packages at special rates for those who desire to join. Also, depending upon the company, other servicesor packages are available with the pagers.

The advantage to this system is that if you are away from any other method of receiving weather information, youcan receive warning and watch information via a pager when threatening weather is moving into the region.

Currently, Wilmington's 56 counties are divided into nine different groups. Each group has been assigned a codenumber so when a warning is sent out for any county in that group, the information will go to the pagers which are codedwith that specific number. The pages are issued at anytime for the following products: severe thunderstorm and tornadowatches, severe thunderstorm, tornado, and flash/flood warnings, winter storm, ice storm, blizzard, heavy snow, andsnow squall warnings, as well as a high wind warning. Also, pages are issued between the hours of 8 AM to 10 PMfor the following products: river flood warning, winter storm watch, high wind warning, flood/flash flood watch, winterweather, snow, and freezing advisories, wind and wind chill advisories, fog advisory, heat advisory, and flood potentialoutlook.

If you are interested in obtaining this service please refer to the enclosed information sheets from both Pagenet andUSA Mobile. Note that this special service is only for Emergency Management Officals and spotters; thus, please donot give the information on these sheets to your friends and family. Once you decide on a company, you will need toeither obtain a pager or have the service added to your pager agreement. In order for the pager to be encoded, you willneed to first show the representative your Skywarn ID card so that he/she can verify that you a member of the Skywarnorganization. You will also need to tell the representative the county for which you desire to receive information. Alsoon the back of the USA Mobile sheet is information which you will need when obtaining the pager. This sheet contains information about the specific pager styles and codes for the county groups for USA Mobile only.

Even though the pager system is convenient, as stated before, this system should only be considered as asecondary means of receiving warning and watch information. Unfortunately, since we are unable to control the timespan it takes to transfer information from the pager company to the pager, we cannot guarantee that you will receive theinformation minutes after the warning is issued. Thus, we recommend that you you still use some other mechanism suchas a NOAA weather radio as your primary avenue for weather information.

By the end of the event, nearly 80 percent of the homes and businesses in Falmouth weredestroyed or had sustained major damage.

Letter From the Editor

As this year's spotter training season comes to a close, I would like to thank everyone who attended a seminar thisyear. For those of you who did not attend, the talk was changed somewhat. We added a new film as well as triedto focus the slide presentation more toward the types of storms which you, as spotters, will likely see. For examplewe added more detail on the characteristics of a squall line rather than spending as much time on a classic supercellthunderstorm.

If you were unable to attend a talk, you will find enclosed a questionnaire. If you could complete the formand return it in the self-addressed stamped envelope, I will then be able to update and verify your information in thespotter database. Each person is entered individually, so if only one person from your residence attended a talk, theremaining skywarn member(s) needs to complete the form(s). As always, if you have any questions, feel free to callat (937) 383-0031 or e-mail me at Diane.Innes@noaa.gov.

One last note, if you were unable to attend a meeting this spring, I strongly urge that you attend one nextyear. We would like all of our spotters to attend a meeting once every two to three years for a refresher on severeweather warning signs. If you are unable to attend one within this time frame, and do not contact us to let us knowthat you are still interested , your name will be dropped from the database. This is necessary to keep the spotterinformation up to date.

New Emergency Alert System

The new automated EAS system should improve the time which it takes for warnings to be aired.

On January 1, 1997, the new Emergency Alert System (EAS) replaced the old Emergency Broadcast System (EBS)for radio and television stations. Cable systems must convert to the new EAS system by around July 1, 1997.

The new EAS system is an automated system while the old EBS system was a manual system. TheNational Weather Service uses the NOAA Weather Radio (NWR) as its interface with the EAS system. Newtechnology added to the NWR called the Specific Area Message Encoder (SAME) allows us to use digital databursts to send coded information for specific severe weather events. This data includes information on the type ofwarning, the county the warning is valid for, the issue time, as well as the length of valid time. Radio stations,television stations, or local county officials who have decoders receive the NWR EAS transmission. Thesedecoders can automatically record the voice transmission of the warning. Radio and television stations in the EASnetwork can broadcast and relay the warning.

Local county officials may also have the capability to encode messages that can be broadcast on the EASnetwork. For example, local counties may wish to put information about hazardous material spills on the EASnetwork.

The new automated EAS system should improve the time which it takes for warnings to be aired. It alsoprovides a way for warnings to be broadcast over radio or television stations that are unattended at night.

The technology that allows NWR to interface with the EAS system will also allow for programmable NWRreceives. These programmable NWR receivers will allow you to decide which watches or warnings you want to bealerted for and for which county(s) you would like these alerts. This would mean that you could set your receiver toonly alert for watches and warnings for your county if you wish. We hope to see these programmable NWRreceivers on the consumer market by the end of this year.

By Mary Jo Parker, WCM

The Devastating Flood of '97: A Meteorologist's Perspective

The presence of this abundant moisture along with a nearly stationary boundary combined to cause very heavy rainfall for greater than a 24 hour period.

Just preceding the Great Flood of '97, ironically much of the weather attention was focused on West Central Ohio. Rainfall had been abundant in this area, and flooding was occurring on the Blanchard, Maumee, Auglaize, and St. Marysrivers. Meanwhile, nearly all the other river levels were low across Southeast Indiana, Southern Ohio, and NorthernKentucky. The computer forecast maps Thursday morning, February 27th showed that conditions were favorable forheavy rains over the upcoming weekend. The big question was exactly how much rain would occur? By late Friday,the computer guidance suggested between 1.5 and 2.5 inches of rainfall would occur near and south of the Ohio River. The computer maps were on the right track, but the heaviest rainfall amounts were grossly underestimated. BetweenFriday night and Sunday, a record amount of rain fell. Actual rainfall amounts ranged between 8 and 12 inches acrossNorthern Kentucky and far South Central Ohio.

The next question to ask was what happened meteorologically to bring such a deluge to the Ohio Valley? The mostimportant feature was a strong and persistent southwesterly flow aloft that transported moisture rich air rapidly into theOhio Valley. At 4000-5000 Feet above the ground, winds were howling at 50 to 70 MPH! These strong winds carrieddeep moisture into the Ohio River Valley in less time than driving the approximately 700 miles from the Gulf Coast,assuming that you stopped for lunch. In the Ohio Valley, if you were to take a small column of air that extended throughmuch of the atmosphere and compared it to a typical column of air for early March, you would have found that duringthe Great Flood the air column contained nearly four times the normal amount of moisture. The presence of thisabundant moisture along with a nearly stationary boundary combined to cause very heavy rainfall for greater than a 24hour period.

The computer guidance did not do a good job in forecasting a low pressure center that developed near Arkansasearly Saturday, March 1st, that later tracked into the Ohio Valley. This low further enhanced the precipitationdevelopment over the flood ravaged areas. The atmosphere continued to destabilize and thunderstorms developedcreating even more boundaries. These boundaries combined with the nearly stationary front, and caused the rain tomove over the same areas for a long period of time. Also since the computer forecasts erroneously moved the frontnorthward, the maximum rainfall generated by the computer guidance was too low. However, the timing of the rainfalland where the heavier rain would occur was handled better by the computers.

The northern edge of the excessive rainfall had a sharp cuttoff. Thus, if the warm front had moved a little farthernorth, the heavy rain would have occurred over a larger area. Flooding would still have occurred, but maybe not thecomplete devastation that struck towns near the Ohio and Licking rivers. Another hard hit area was along the OhioBrush Creek in South Central Ohio. Flash flooding occurred there where the river rose 16 feet above its flood stage! In the town of West Union in Adams county Ohio, 9.42 inches of rain was recorded during the weekend.

The Great Flood of '97 is the worst flooding that the Ohio Valley has seen in the past 33 years. As NationalWeather Service meteorologists , our mission is to issue warnings that save lives and help protect property. Although,rainfall as high as 1 foot was not expected, there were many timely flash flood and river flood warnings issued by ouroffice that met our mission goals.

By Ryan Sandler, ILN Meteorologist

Welcome To New Spotters

This spring's spotter talks were extremely productive. Not only did older members come to refresh their memoryon the warning signs of severe weather but we had many new faces attend as well. We added approximately 700new members to the spotter program this year.

For those of you who are new members, this article will explain the Spotter ID's as well as yourresponsibility as a weather spotter. Some of the following information may have been stated at the seminars;however, I just wanted to take the opportunity to reiterate a few points.

To begin with, what is a spotter ID? Your spotter ID is a number which has been geographically assigneddepending upon the location of your residence within the county. The first letter indicates the state while the secondtwo letters represent a county code for the county in which you live. The remaining digits represents a spotternumber. If by some chance when you receive your ID and you cannot read it or you believe that your residence hasbeen placed in the wrong county, please contact me immediately at the number listed at the end of this article.

For people who are a part of the amateur radio organization, do not use your spotter ID when relaying areport over the radio network. Only use your ID when actually phoning in a report. Also for anyone who calls in areport please always give your spotter ID. This is helpful to us in pinpointing the damage or location of the storm.However, if you have spotted the severe weather from somewhere other than your residence, please also detailwhere the severe weather occurred.

Also indicated on the ID card is a listing of severe weather, both winter and summer, which we would likeyou to report. When relaying this information either by phone or radio, please try to be as concise as possible on thetype of damage, hail, and etc. as well as the time which the event occurred.

Finally, remember the toll free severe weather spotter line should only be used to report severe weatherinformation. If you have any questions or are just interested in obtaining weather information, please use the publicline (937) 383-0031 rather than the toll free line in those situations.

New Information On the Internet

As many of you have probably realized by now, Wilmington's internet address has changed since the last newsletter. The new address is www.nws.noaa.gov/er/iln. We are sorry for any inconvenience and confusion that this change mayhave caused.

If you have never visited the web site or have been unable to find it for awhile, you may want to visit it soon. Manynew and exciting sections have been added within the past few months.

A few interesting additions include a trivia page, a picture gallery, new links to other web sites, as well as a pageof current severe weather information.

The page of current severe weather information includes products such as Storm Predication Center Day 1 and Day2 severe weather outlooks, information about severe weather which occurred the previous day across the nation, as wellas any current watches, warnings or statements. This is a good reference section to discover if severe weather isexpected across the area that day or which locations are currently receiving severe weather .

The most exciting new addition, in my mind though, is the Skywarn page. One can find a sundry of informationsuch as the spotter guides, spotter safety, an on-line edition of the Newsletter, as well as the Skywarn training schedule. If there is anything else that you would like to see added to the web page, let me know. My e-mail address isDiane.Innes@noaa.gov. You could also just call with the suggestions at (937) 383-0031 or write at 1901 South SR 134Wilmington OH 45177, Attn: Diane Innes.

Naming Of The Newsletter

As evident by the title of the newsletter, we have a winner in the contest. Joan Pitula from Cincinnati sent in theentry of Sky Scoop. I hope that everyone approves the new name.

Thank-you to everyone who took the time and effort to send in their entries. I, along with the rest of theselection committee, was amazed by all of the creative names which you entered. It was not an easy selection butthe committee jointly agreed that Sky Scoop was both a catchy and appropriate name for the newsletter.

As promised the trophy of the contest was a National Weather Service mug which was recently mailed to Ms. Pitula.

Severe Weather Definition And Safety Tips

With the return of the warm temperatures and mild breezes also returns the threat for severe thunderstorms. Therefore,the following is just a reminder of a few definitions and safety tips.

The official definition of a severe thunderstorm is a thunderstorm which produces winds 58 MPH or higher and/orhail 3/4 of an inch or larger in diameter. A severe thunderstorm watch means conditions are favorable for severethunderstorms to develop, where as a severe thunderstorm warning means that a severe thunderstorm is occurring oris imminent.

A tornado is a violently rotating column of air which is extended from the cloud base to the ground. When atornado watch is issued this means that tornadoes may develop in and near the watch area. A tornado warning indicatesthat a tornado has either been sighted or is indicated by the radar.

A flash flood is a flood which occurs within six hours of a heavy rain event. If a flash flood watch is issued, thismeans that flash flooding or flooding is possible in the watch area. A flash flood warning means that flash flooding hasbeen reported or is imminent. An urban and small stream flood warning means flooding of small streams, streets, andlow-lying areas such as railroad underpasses and urban storm drains is occurring or likely to occur.

The following are a few safety tips if caught in a severe thunderstorm, tornado, or flash flooding situation. In theevent of a Severe Thunderstorm: 1) Take shelter in a sturdy shelter and stay away from windows or take shelter insidea hard top car and keep the windows rolled up. 2) Get out of a boat and stay away from water, 3) If caught in theoutdoors do not take shelter in small sheds or under isolated trees. Instead crouch in a low spot away from trees, fencesor poles, 4) Do not take a bath or shower, and 5) Do not use the phone or other electrical devices. In the event of aTornado: 1) Go to an interior room or hallway of the lowest floor or basement of a home or building. 2) stay away fromwindows, 3) If caught outside or in a vehicle, lie flat in a ditch or depression, 4) Abandon a mobile home for a sturdierstructure. Finally, during Flash Flooding: 1) evacuate immediately to higher ground if a flood warning is issued orflooding is observed, 2) never drive through a flooded roadway since most flood related deaths occur when peopleattempt to drive through flood waters., 3) if water is flowing above your ankles, take another route, and 4) never allowchildren to play around high water, storm drains, or ditches.

First Tornado of the Season

On May 14, 1997 at approximately 500 PM, a mini supercell thunderstorm developed in northern Butler CountyOhio. This storm developed along a warm front which was appended to a low in Indiana. Before becomingsupercellular, this storm produced large quarter to ping pong size hail (1 inch to 1 1/4 inches in diameter) in Warrenand Greene Counties. However, by the time the storm reached north central Clinton county, it had become asupercell and had developed a wall cloud.

In northeastern Clinton County the storm spawned a tornado(s) which initially touched down near Sabinajust after 600 PM EDT. The mini supercell thunderstorm continued its treck east across Fayette County, just southof Washington Court House, and along the Pickaway and Ross County borders. The storm finally diminished innorthwestern Hocking County approximately 45 miles east and an hour and a half to two hours after the initialtornado touchdown. According to eyewitness reports, the tornado(s) width was about 1/2 mile as it moved fromSabina and into Fayette county. However, as the tornado(s) moved across Ross and Pickaway County, the widthdecreased to around a 1/4 of a mile.

A team from the Wilmington office conducted both an areal and ground survey on the 15th. After theinvestigation of the tornado path, the survey team concluded that the tornado(s) touched down and lifted off theground several times during the one and a half to two hour period.

Some of the more extensive damage caused by the storm included a roof blown off a barn near route 23 innorthern Ross county. Damage of this magnitude indicates that the tornado(s) had an intensity of F1 on the FujitaScale at that time. Estimated wind speeds with an F1 tornado, which is classified as a weak tornado, range between73 to 112 MPH.