Hopkins Co. Tornado of November 15th, 2005. Photo by Leonard Costanzo.
What do the nation’s strongest tornado in 2005 and the longest track tornado in Kentucky since 1974 have in common? They both happened during autumn severe weather outbreaks.
We all know about spring and severe weather. Spring and violent weather seem to go hand-in-hand for much of the southern and central United States, and southeast Missouri, southern Illinois, southwest Indiana and western Kentucky are often in the weather crosshairs. During this transition from winter to summer, the clash of warm moist air colliding with the cold dry Canadian air nearly always sets the stage for some of the most violent weather that Mother Nature has in her arsenal.
According to the National Weather Service’s Storm Prediction Center (SPC), May and June are the peak months for tornado and other aspects of severe weather development. But there is also the surprising statistic, that late autumn also has a surge of severe weather. This “second season” occurs mainly across the southeast portion of the United States, including our area, with November as the focus of the greatest number of severe weather instances. However, it is important to note that severe weather can happen throughout the winter months.
Here are a few other facts...
Why a resurgence in tornado potential in the autumn months? It all has to do with a combination of fast Jet Stream winds and strong frontal systems which reappear in fall. During the late summer months thunderstorms are common, but winds throughout the atmosphere rarely are strong enough to allow tornadoes to form. During the spring and Fall however, a strong gradient of temperatures across the hemisphere typically drives powerful Jet Stream winds, and creates much stronger frontal systems which help initiate thunderstorm development.
Over the last decade, the Lower Ohio/Middle Mississippi Valley, including much of the four state area, ranks among the nation’s highest frequency of strong and violent tornadoes. Several of these violent and deadly tornadoes have occurred during the fall and winter, a time of year many in our area do not associate with severe weather. Being ready for severe weather is not just for the spring season. Tornadoes and other forms of severe weather can happen year round, day or night.
Keep an eye on the forecast. Be especially vigilant when it is unusually warm or humid, as that often precedes severe weather in our area. Many of the tornadoes that form during the winter form during the night. A NOAA Weather Radio may be your best defense against nighttime tornadoes.
Note that this graph is only 14 years worth of data.
For more information on severe thunderstorms and tornadoes including safety tips and educational sites for children, visit the National Weather Service’s Severe Weather Awareness Page.
Below is a statement issued by the NWS on September 24, 2010.
...BE READY FOR THE FALL SEVERE WEATHER SEASON...
WHILE SPRING IS TYPICALLY THE OVERALL PEAK TIME OF YEAR FOR
SEVERE WEATHER...FALL IS OUR SECONDARY PEAK SEVERE WEATHER SEASON.
SOMETIMES THE FALL MONTHS BRING OUR MOST INTENSE AND DEADLY
TORNADOES. RECENT HISTORY PROVIDES A STRONG TESTAMENT TO THE FALL
SEVERE WEATHER SEASON IN OUR REGION.
2007 - OCTOBER 18 - A MAJOR TORNADO OUTBREAK OCCURS SETTING RECORDS
FOR NUMBER (16) AND INTENSITY (F3 IN DAVIESS COUNTY, KY)
2006 - SEPTEMBER 22 - VIOLENT F4 TORNADO HITS SOUTHEAST MISSOURI
AND SOUTHERN ILLINOIS; ONE OF 10 TORNADOES IN THIS RECORD
2005 - NOVEMBER 6 - AN F3 TORNADO STRIKES THE EVANSVILLE, IN AREA
AT 2 AM...KILLING 25.
NOVEMBER 15 - AN F4, THE NATION`S STRONGEST TORNADO FOR
THE YEAR HITS HOPKINS COUNTY, KY. AN F3 TRAVELS 44.1 MILES
ACROSS WESTERN KY CAUSING DEATH AND MASSIVE DESTRUCTION.
2004 - OCTOBER 18 - THE SECOND WORST TORNADO OUTBREAK OF THE YEAR
IN OUR REGION; SPAWNS 2 F2 TORNADOES CAUSING INJURIES IN
2002 - SEPTEMBER 20 AND NOVEMBER 10 - TORNADOES STRIKE SOUTHERN
IL AND SOUTHWEST IN.
2001 - OCTOBER 24 - A DAMAGING THUNDERSTORM WIND EVENT INJURES AT
AT LEAST 16 AND CAUSES $1.5 MILLION IN LOSSES FROM CAPE
GIRARDEAU, MO TO EVANSVILLE, IN. NOVEMBER 24 - AN F2
TORNADO STRIKES CALLOWAY COUNTY, KY NEAR DAYBREAK CAUSING
IN PREPARATION FOR THE FALL SEVERE WEATHER SEASON...THERE ARE SEVERAL
KEY THINGS YOU NEED TO MAKE SURE YOU HAVE IN PLACE.
FIRST...IT IS CRITICAL...POTENTIALLY A MATTER OF LIFE AND
DEATH...THAT YOU HAVE A WAY TO BE ALERTED OF A WARNING. A WEATHER
RADIO CAN AUDIBLY ALERT YOU ANYTIME A WARNING IS ISSUED FOR YOUR
AREA. A WEATHER RADIO IS EXTREMELY IMPORTANT FOR TORNADOES THAT
OCCUR OVERNIGHT OR DURING OTHER MORE VULNERABLE TIMES. ANOTHER
DEVICE THAT CAN SERVE AS AN INVALUABLE WARNING ALERT TOOL IS A
CELL PHONE. SOME MEDIA AND OTHER SOURCES PROVIDE WARNING ALERTS
VIA CELL PHONE TEXT MESSAGES.
SECOND...IT IS KEY TO YOUR SAFETY THAT YOU HAVE A PLAN IN PLACE AND
KNOW WHAT ACTION TO TAKE ONCE A WARNING IS ISSUED OR SEVERE
WEATHER IS OBSERVED. KNOW WHERE TO GO WHETHER YOU ARE AT HOME...AT
WORK...AT SCHOOL...ON THE ROAD...OR ANYWHERE ELSE.
IF YOU ARE GOING TO BE AT A LARGE GATHERING...SUCH AS AT A
SCHOOL...STADIUM...OR PLACE OF WORSHIP...MAKE SURE THAT SOMEONE
HAS BEEN DESIGNATED TO KEEP UP WITH THE WEATHER.
IF A WARNING IS ISSUED FOR YOUR AREA...
WHEN INDOORS...STAY AWAY FROM OUTSIDE WALLS AND WINDOWS AND GO TO
AN INTERIOR ROOM ON THE LOWEST LEVEL. AVOID USING ELECTRICAL
APPLIANCES WHILE THE STORM IS NEARBY.
IN OPEN COUNTRY...YOU SHOULD SEEK SHELTER AND AVOID TREES WHICH
CAN BE TARGETS FOR LIGHTNING. IF THERE IS NO SHELTER...GO TO A
DITCH OR CULVERT BUT BEWARE OF RISING WATER WHICH CAN CAUSE
IN MOBILE HOMES...WHETHER IT IS TIED DOWN OR NOT...LEAVE AND SEEK
NEARBY SAFE SHELTER.
LARGE BUILDINGS SUCH AS SHOPPING MALLS...HOSPITALS...AS WELL AS
NURSING HOMES...AND SCHOOLS HAVE PRE-ARRANGED SAFETY PLANS AND
DESIGNATED SAFE AREAS. FOLLOW THE INSTRUCTIONS GIVEN INSIDE THESE
AS A REMINDER A TORNADO WATCH MEANS THAT CONDITIONS ARE FAVORABLE
FOR TORNADOES...LARGE HAIL AND DAMAGING THUNDERSTORM WINDS. A
TORNADO WARNING MEANS A TORNADO HAS ACTUALLY BEEN OBSERVED BY A
STORM SPOTTER OR DETECTED BY RADAR. ACTION SHOULD BE TAKEN
IMMEDIATELY WHEN A WARNING IS ISSUED.