A very moist air mass and weak steering currents allowed for diurnal convection to produce localized heavy rainfall.
Every event with a place to put it. 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 very moist air mass and weak steering currents allowed for diurnal convection to produce localized heavy rainfall.
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 Sep 4, 1:35 PM EST, 3 hours 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 235 PM EDT THU SEP 4 2014 .SHORT TERM (TONIGHT AND FRIDAY)... A MOIST AIR MASS AND MIDLEVEL SHEAR ZONE BETWEEN TWO RIDGES WILL REMAIN OVER THE REGION THROUGH FRIDAY. WITH LITTLE PATTERN CHANGE...WILL FOLLOW MAINLY A PERSISTENCE FORECAST. THE NAM SEEMS TO BE PERFORMING PRETTY WELL WITH THE PATTERN...AND THE HRRR HAS BEEN RELIABLE IN DEPICTING AREAS OF AND TIMING OF CONVECTION. IT SHOWS ONGOING PRECIP LINGERING IN NE SECTIONS UNTIL DISSIPATING AROUND MIDNIGHT...AND WILL FOLLOW THAT SOLUTION FOR TONIGHT. AS WE SAW THIS MORNING...PATCHY FOG AND LOW CLOUDS CAN BE EXPECTED TO START THE DAY IN MOST SPOTS. THE ONE DIFFERENCE IN THE NAM TOMORROW APPEARS TO BE THAT THE 700 MB DEFORMATION/SHEAR ZONE SHIFTS SLIGHTLY TO THE SOUTH AND EAST...WHICH MAY LEAD TO SOUTHERN AND EASTERN AREAS BEING A BIT MORE FAVORED FOR AFTERNOON CONVECTION THAN NORTHERN AND WESTERN AREAS. STILL...WILL HAVE CHANCE POPS EVERYWHERE TOMORROW AFTERNOON. GFS MOS HIGH TEMPS APPEAR TOO WARM TOMORROW...AND HAVE VERIFIED TOO WARM THE PAST FEW DAYS...SO WILL UNDERCUT THEM BY SEVERAL DEGREES. .LONG TERM (FRIDAY NIGHT THROUGH THURSDAY)... A COLD FRONT WILL MOVE THROUGH THE AREA SATURDAY EVENING...WITH SHOWERS AND THUNDERSTORMS DEVELOPING THROUGH THE DAY SATURDAY AHEAD OF THIS FRONT. INSTABILITY AND SHEAR ARE UNIMPRESSIVE...SO LOOKING AT MAIN THREAT OF HEAVY RAIN WITH THESE STORMS. NEAR ZONAL FLOW WIL SET UP OVER THE AREA BEHIND THIS FRONT. THE AIRMASS DOES NOT YEILD MUCH CHANGE IN THE WAY OF COOLER TEMPERATURES SUNDAY THROUGH THE END OF THE PERIOD. BUT DOES HAVE DRIER AIR ADVECTED IN THE MIDLEVELS. THIS ALONG WITH THE AFTERNOON HEATING...EXPECTING TO SEE DIURNAL THUNDERSTORMS EACH DAY. UPPER LEVEL MOISTURE WILL CONTINUE TO INCREASE THROUGH THIS PERIOD...SO WILL ONLY SEE PARTLY CLOUDY SKIES FOR A DAY OR TWO AT THE BEGINNING OF THE WORK WEEK. THE NEXT BIG FEATURE MOVING INTO THE AREA IS ANOTHER COLD FRONT SET TO MOVE IN TOWARDS THE END OF NEXT WEEK. MODELS DIFFER ON TIMING AND STRENGTH OF THIS SYSTEM...SO SETTLED FOR CHANCE POPS THURSDAY AND FRIDAY. TEMPERATURES WILL BE A COUPLE OF DEGREES ABOVE NORMAL FOR THIS TIME OF YEAR. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 70 89 69 87 / 20 50 20 50 KNOXVILLE MCGHEE TYSON AIRPORT, TN 69 87 68 86 / 20 40 20 60 OAK RIDGE, TN 68 87 68 86 / 20 40 20 60 TRI CITIES AIRPORT, TN 66 87 64 86 / 40 40 20 60 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && DGS/JW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MORRISTOWN TN 402 AM EDT THU SEP 4 2014 NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002- 005-006-008-050815- 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 EDT THU SEP 4 2014 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST NORTH CAROLINA...EAST TENNESSEE AND SOUTHWEST VIRGINIA. .DAY ONE...TODAY AND TONIGHT... A PLUME OF TROPICAL MOISTURE WILL CONTINUE TO MOVE NORTH ACROSS THE SOUTHERN APPALACHIANS. THE MOIST AND UNSTABLE AIR WILL PRODUCE SCATTERED TO BROKEN AREAS OF SHOWERS AND THUNDERSTORMS...MAINLY FOR THIS AFTERNOON AND EVENING. A FEW STRONG STORMS WILL BE POSSIBLE...WITH THE MAIN THREATS BEING GUSTY WINDS UP TO 40 MPH AND LOCALLY HEAVY RAINFALL DUE TO VERY SLOW MOVEMENT. MINOR FLOODING OF LOW LYING AREAS COULD OCCUR AS THE STORMS REMAIN NEARLY STATIONARY OR DRIFT SLOWLY NORTHEAST. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY... SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP EACH DAY THROUGH THE WEEKEND...ESPECIALLY DURING THE AFTERNOON AND EVENING HOURS. A FEW STORMS COULD POSSIBLY BECOME STRONG TO SEVERE EACH DAY...BRINGING THE POSSIBILITY OF DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED DUE TO THE ISOLATED NATURE OF THE EXPECTED THREATS.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
459 PM EDT THU SEP 04 2014
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0450 PM FLASH FLOOD 5 NE BRISTOL VA 36.66N 82.10W
09/04/2014 WASHINGTON VA EMERGENCY MNGR
STANDING WATER AT THE INTERSECTION OF JONESBOROUGH RD AND
LONE EAGLE RD. ROAD NOT YET CLOSED.
&&
TGSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
524 PM EDT THU SEP 4 2014
TNZ042-044-042215-
WASHINGTON-NORTHWEST GREENE-
524 PM EDT THU SEP 4 2014
...A STRONG THUNDERSTORM WILL AFFECT WASHINGTON AND NORTHWEST
GREENE COUNTIES...
AT 523 PM EDT...A STRONG THUNDERSTORM WAS NEAR GRAY...OR 10 MILES
SOUTH OF KINGSPORT...MOVING EAST AT 10 MPH.
WINDS IN EXCESS OF 30 MPH ARE POSSIBLE WITH THIS STORM.
LOCATIONS IMPACTED INCLUDE...
JOHNSON CITY...OAK GROVE...GRAY...SPURGEON AND FALL BRANCH.
TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY CAUSE
LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.
CLOUD TO GROUND LIGHTNING IS ALSO OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.
LAT...LON 3629 8270 3640 8272 3642 8268 3644 8267
3642 8260 3644 8242 3643 8240 3642 8241
3643 8239 3642 8238 3641 8238 3641 8237
3639 8239 3640 8237 3634 8236
TIME...MOT...LOC 2123Z 256DEG 7KT 3638 8260
AMP.23The Knoxville radar (KMRX), 128 km away, was scanning. The volume nearest the first event began at 21:43 UTC.
1 flash flood. Local standard time, as filed.
Flooding on Bethesda Road. Flowing water causing road closures.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Virginia in 2014Every state in 2014This day in weather historyWarnings in Virginia, September 2014
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: 535767.