A powerful southerly low level jet was in place across the Appalachian Mountains. The strong winds aloft were brought down to the surface in the lee of the mountain range generating significant damage across extreme Northeast Tennessee.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 MRX wrote it up.
A powerful southerly low level jet was in place across the Appalachian Mountains. The strong winds aloft were brought down to the surface in the lee of the mountain range generating significant damage across extreme Northeast Tennessee.
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 Morristown, TN wrote its last area forecast discussion before the first event at Mar 9, 3:30 AM EST, 1 hour earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
330 AM EST WED MAR 9 2011
.SHORT TERM (TODAY AND TONIGHT)...STRONG STORM SYSTEM ALREADY MAKING
AN IMPACT ON THE SOUTHERN APPALACHIAN REGION WITH STRENGTHENING
WINDS ALOFT AS LOW LEVEL JET PRESSES EAST ACROSS THE MID SOUTH.
STAYED WITH THE WIND ADVISORY THROUGH THIS EVENING AS FRONTAL PUSH
SHOULD BE ABLE TO MIX STRONG FLOW ALOFT TO THE SURFACE AS IT
ADVANCES TOWARD THE MOUNTAINS. THE OTHER MAIN FEATURE IN ASSOCIATION
WITH THIS SYSTEM WILL BE THE PROLONGED PERIOD OF HEAVY RAIN AS VERY
HIGH PRECIPITABLE WATER STREAMS NORTH INTO THE REGION. THE MOISTURE
WILL BE EFFICIENTLY LIFTED IN A SCENARIO WHICH INCLUDES A LENGTHY
PERIOD OF CONVERGENCE AHEAD OF A SLOW MOVING UPPER LEVEL TROUGH WITH
STRONG DIVERGENCE ALOFT IN THE ENTRANCE REGION OF 120 KT JET. STAYED
WITH A CHANCE FOR CONVECTION ACROSS MUCH OF THE FORECAST AREA WHILE
SHIFTING TO CATEGORICAL CONVECTIVE POPS FOR SOUTHEAST TENNESSEE AND
SOUTHWEST NORTH CAROLINA LATER IN THE DAY AS NARROW INSTABILITY AXIS
BUILDS EAST AHEAD OF SYSTEM COLD FRONT. AREAL PRECIP TOTALS WILL BE
IN THE 1-2 INCH RANGE WITH LOCALIZED AMOUNTS CLOSE TO 3 INCHES
ACROSS SOUTHEAST TENNESSEE AND SOUTHWEST NORTH CAROLINA WHERE THE
BEST COMBINATION OF MOISTURE AND LIFT WILL BE LOCATED. A FLOOD WATCH
WILL REMAIN IN EFFECT UNTIL LATE EVENING DUE TO TIMING OF HEAVY RAIN
IN PROXIMITY TO THE RECENT TWO WEEK PERIOD OF EXCESSIVE RAINFALL THE
REGION HAS EXPERIENCED. MAX TEMPERATURE FORECAST COULD BE
CHALLENGING AS USUAL WITH STRONG SOUTHERLY DOWNSLOPE FLOW POSSIBLY
ALLOWING THE NORTHERN GREAT VALLEY TO BECOME A LITTLE WARMER THAN
SOUTHEAST TENNESSEE. USED A GUIDANCE BLEND FOR MAX TEMPS.
.LONG TERM (THURSDAY THROUGH TUESDAY)...UPPER TROUGH WILL BECOME
NEGATIVELY TILTED AND TRANSITION INTO A CLOSED LOW AS IT CROSSES THE
APPALACHIANS ON THURSDAY. COLD ADVECTION BEHIND THE 850 MB TROUGH ON
THURSDAY WILL RESULT IN TEMPS NEARLY STEADY OR SLOWLY FALLING
THROUGH THE DAY. FALLING MIDLEVEL TEMPS WILL CREATE INSTABILITY FOR
SHOWERS. BY THURDAY EVENING PRECIP WILL TRANSITION TO SNOW
SHOWERS...WHICH WILL CONTINUE INTO FRIDAY MORNING. THE NAM PRODUCES
WARNING-CRITERIA SNOW AMOUNTS IN THE MOUNTAINS...BUT THIS APPEARS
OVERDONE AS THE GFS AND SREF SHOW MUCH LESS. A 25 KT NW FLOW WILL
ENHANCE SNOW AMOUNTS IN HIGHER ELEVATIONS...BUT THE LACK OF SYNOPTIC
LIFT AND SMALL WINDOW OF ADEQUATE MOISTURE DEPTH SHOULD HELP LIMIT
AMOUNTS TO ADVISORY LEVELS OR LOWER. TEMPS NEAR TO JUST ABOVE
FREEZING WILL PREVENT MUCH ACCUMULATION IN VALLEY LOCATIONS.
THE REST OF THE LONG TERM WILL REMAIN RELATIVELY UNCHANGED. A SERIES
OF FAST-MOVING SHORTWAVE TROUGHS WILL KEEP TEMPERATURES BELOW
NORMAL...BUT WITH MOISTURE LACKING WE SHOULD STAY DRY THROUGH THE
WEEKEND. THE GFS AND ECMWF ARE QUITE DIFFERENT FOR DAYS 6 AND 7...SO
WILL LEAVE THE CURRENT SLIGHT CHANCE POPS GOING.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 61 44 49 34 54 / 100 50 40 20 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 58 43 48 32 49 / 100 60 50 40 0
OAK RIDGE, TN 58 43 46 32 51 / 100 60 50 40 0
TRI CITIES AIRPORT, TN 57 46 52 30 45 / 100 80 70 70 20
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
CHEROKEE...CLAY.
WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR THE FOLLOWING
ZONES: CHEROKEE...CLAY.
TN...FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
ANDERSON...BLEDSOE...BLOUNT SMOKY MOUNTAINS...BRADLEY...
CAMPBELL...COCKE SMOKY MOUNTAINS...EAST POLK...HAMILTON...
KNOX...LOUDON...MARION...MCMINN...MEIGS...MORGAN...NW
BLOUNT...NORTH SEVIER...NORTHWEST MONROE...RHEA...ROANE...
SCOTT TN...SEQUATCHIE...SEVIER SMOKY MOUNTAINS...SOUTHEAST
MONROE...UNION...WEST POLK.
WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR THE FOLLOWING
ZONES: BLOUNT SMOKY MOUNTAINS...COCKE SMOKY MOUNTAINS...
EAST POLK...JOHNSON...NW BLOUNT...NORTH SEVIER...NORTHWEST
CARTER...NORTHWEST COCKE...NORTHWEST GREENE...SEVIER SMOKY
MOUNTAINS...SOUTHEAST CARTER...SOUTHEAST GREENE...SOUTHEAST
MONROE...UNICOI...WASHINGTON TN.
FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES:
CLAIBORNE...GRAINGER...HAMBLEN...HANCOCK...HAWKINS...
JEFFERSON...JOHNSON...NORTHWEST CARTER...NORTHWEST COCKE...
NORTHWEST GREENE...SOUTHEAST CARTER...SOUTHEAST GREENE...
SULLIVAN...UNICOI...WASHINGTON TN.
VA...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR THE FOLLOWING
ZONES: RUSSELL...WISE.
FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES: LEE...
RUSSELL...SCOTT...WASHINGTON...WISE.
&&
20/DGSHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MORRISTOWN TN 402 AM EST WED MAR 9 2011 NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002- 005-006-008-100915- CHEROKEE-CLAY-SCOTT TN-CAMPBELL-CLAIBORNE-HANCOCK-HAWKINS- SULLIVAN-JOHNSON-MORGAN-ANDERSON-UNION-GRAINGER-HAMBLEN- NORTHWEST COCKE-COCKE SMOKY MOUNTAINS-NORTHWEST GREENE- SOUTHEAST GREENE-WASHINGTON TN-UNICOI-NORTHWEST CARTER- SOUTHEAST CARTER-ROANE-LOUDON-KNOX-JEFFERSON-NW BLOUNT- BLOUNT SMOKY MOUNTAINS-NORTH SEVIER-SEVIER SMOKY MOUNTAINS- SEQUATCHIE-BLEDSOE-RHEA-MEIGS-MCMINN-NORTHWEST MONROE- SOUTHEAST MONROE-MARION-HAMILTON-BRADLEY-WEST POLK-EAST POLK-LEE- WISE-SCOTT-RUSSELL-WASHINGTON- 402 AM EST WED MAR 9 2011 /302 AM CST WED MAR 9 2011/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST NORTH CAROLINA...EAST TENNESSEE AND SOUTHWEST VIRGINIA. .DAY ONE...TODAY AND TONIGHT A LOW PRESSURE SYSTEM WILL SHIFT EAST INTO THE REGION TODAY. STRONG SOUTHERLY WINDS IN ASSOCIATION WITH THIS SYSTEM WILL CONTINUE ACROSS THE AREA TODAY WHILE WEAKENING LATER THIS EVENING. SUSTAINED WINDS OF 20 TO 35 MPH WITH GUSTS UP TO 50 MPH ARE EXPECTED OVER THE MOUNTAINS AND ADJACENT FOOTHILLS. A WIND ADVISORY IS IN EFFECT FOR THIS AREA. HEAVY RAINFALL WILL MOVE INTO THE AREA THIS MORNING AND WILL CONTINUE THROUGH THIS EVENING. DUE TO MOIST SOIL CONDITIONS AND ELEVATED RIVER LEVELS ALREADY IN PLACE...FLOODING IS EXPECTED. A FLOOD WATCH IS IN EFFECT FOR THE ENTIRE AREA. BE PREPARED TO MOVE TO HIGHER GROUND IF FLOODING DEVELOPS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY MUCH COLDER AIR WILL FLOW INTO THE REGION BY THURSDAY AFTERNOON AND EVENING...AND WILL PRODUCE SCATTERED SNOW SHOWERS INTO THURSDAY NIGHT. A DUSTING UP TO 2 INCHES OF SNOW COULD ACCUMULATE BY FRIDAY MORNING...MAINLY IN THE HIGHER ELEVATIONS OF SOUTHWESTERN VIRGINIA AND NORTHEAST TENNESSEE. SOME LOCALLY HEAVIER AMOUNTS OF 3 INCHES OR MORE COULD FALL ABOVE 5000 FEET IN THE SMOKIES. STAY TUNED FOR MORE DETAILS AND UPDATES. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED TODAY AND TONIGHT DUE TO THE POTENTIAL FOR FLOODING.
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Strong south winds descending from the adjacent Appalachian Mountains damaged the roof at Camp Creek Elementary School.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Tennessee in 2011Every state in 2011This day in weather historyWarnings in Tennessee, March 2011
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: 282033.