Alert archive / Tennessee / Special Weather Statements in 2021

Special Weather Statement, NWS Morristown, TN

May 4, 2021Polk County, Tennessee; Cherokee County, North Carolina

NWS Morristown, TN issued this special weather statement at May 4, 2021, 12:06 PM EDT for Polk County, Tennessee; Cherokee County, North Carolina. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 4, 2021, 12:06 PM EDT (16:06 UTC)
Expired
May 4, 2021, 12:30 PM EDT
In force
24 min
Issued by
NWS Morristown, TN

Counties Cherokee County, NC, Polk County, TN

The radar

The Knoxville radar (KMRX), 152 km from the middle of the area, began a volume at 16:06 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 4.1 hours before the alert went out and 188 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Peachtre/Fal Fld, GA at 12:00Z on 2021-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 590 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2021-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
590 J/kg
Mixed-layer CIN
-114 J/kg
Mixed-layer LCL
753 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
213 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, 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 this special weather statement went out at May 4, 11:04 AM EDT, 1 hour 2 minutes earlier.

Area forecast discussion, May 4, 11:04 AM EDT, 1 hour 2 minutes before
AREA FORECAST DISCUSSION
National Weather Service Morristown TN
1104 AM EDT Tue May 4 2021

.UPDATE...
MORNING UPDATE.

&&

.DISCUSSION...

Severe threat remains this morning as a line of showers and
thunderstorms are moving through the area. Surface based
instability continues to wane, however, plenty of elevated
instability continues to support these thunderstorms. Damaging
winds should be the main threat for the remainder of the late
morning and early afternoon. A substantial cold pool behind the
convection will keep conditions quiet this afternoon but much
drier air aloft will promote increased lapse rates and airmass
recovery to the west. How much recovery takes place across the
Tennessee Valley remains in question. CAMs continue to lead to
uncertainty regarding severe potential this afternoon/evening.
Will continue to monitor. Updated grids have been published.

Diegan

&&

.AVIATION...
12Z TAF DISCUSSION.

Showers and thunderstorms are anticipated to be in the general
area for most of the day today. Certainty on the exact timing of
the storms is low due to model variances with the extent of
convection late this morning and in the evening. Expect generally
MVFR to VFR conditions outside of storms, but all airports will
likely be impacted by several rounds of thunderstorms today. Fog
looks likely overnight, but left mention out for now to keep TAF
length down.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             80  62  73  49  72 /  90  80  20   0   0
Knoxville McGhee Tyson Airport, TN  80  61  71  47  67 /  80  60  40   0  10
Oak Ridge, TN                       78  59  70  46  67 /  80  60  40   0  10
Tri Cities Airport, TN              80  60  70  43  65 /  70  60  60   0  10

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
Hazardous weather outlook, May 4, 2:57 AM EDT, 9 hours 9 minutes before
Hazardous Weather Outlook
National Weather Service Morristown TN
257 AM EDT Tue May 4 2021

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-
005-006-008-050700-
Cherokee-Clay-Scott-Campbell-Claiborne-Hancock-Hawkins-Sullivan-
Johnson-Morgan-Anderson-Union-Grainger-Hamblen-Northwest Cocke-
Cocke Smoky Mountains-Northwest Greene-Southeast Greene-
Washington-Unicoi-Northwest Carter-Southeast Carter-Roane-Loudon-
Knox-Jefferson-Northwest 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-Russell-
257 AM EDT Tue May 4 2021 /157 AM CDT Tue May 4 2021/

This Hazardous Weather Outlook is for portions of southwest North
Carolina...east Tennessee and southwest Virginia.

.DAY ONE...Tonight

Strong to severe thunderstorms will be possible this morning and
again this evening. Damaging wind, large hail are the main
threats, but an isolated tornado cannot be ruled out. In
addition, multiple rounds of moderate to heavy rainfall will
further increase the potential for isolated flash flooding today.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to relay reports of severe weather and
flooding to our office today.

In the hours before

Local storm report, May 4, 11:07 AM EDT, 59 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1107 AM EDT TUE MAY 4 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0430 AM     HAIL             OLIVER SPRINGS          36.04N 84.34W
05/04/2021  E0.88 INCH       ANDERSON           TN   PUBLIC

            CORRECTS PREVIOUS HAIL REPORT FROM OLIVER
            SPRINGS. VIA SOCIAL MEDIA POST.

&&
Local storm report, May 4, 11:12 AM EDT, 54 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1112 AM EDT TUE MAY 4 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1010 AM     TSTM WND DMG     3 SSW OAK RIDGE         35.92N 84.33W
05/04/2021                   ROANE              TN   911 CALL CENTER

            COUPLE TREES DOWN.

&&
Local storm report, May 4, 11:14 AM EDT, 52 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MORRISTOWN TN
1114 AM EDT TUE MAY 4 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1010 AM     TSTM WND DMG     3 SSW OAK RIDGE         35.92N 84.33W
05/04/2021                   ROANE              TN   911 CALL CENTER

            COUPLE TREES DOWN.

0955 AM     TSTM WND DMG     PIKEVILLE               35.61N 85.20W
05/04/2021                   BLEDSOE            TN   911 CALL CENTER

            NUMEROUS TREES DOWN AND TRAILER BLOWN OVER
            IN THE PIKEVILLE AREA.

0945 AM     TSTM WND DMG     2 ENE HIGH POINT        36.16N 84.79W
05/04/2021                   MORGAN             TN   911 CALL CENTER

            SEVERAL TREES DOWN ALONG HWY 62 IN THE
            CHESTNUT RIDGE COMMUNITY.

0750 AM     FLASH FLOOD      PIGEON FORGE            35.79N 83.56W
05/04/2021                   SEVIER             TN   911 CALL CENTER

            MULTIPLE ROADS CLOSED IN THE AREAS
            SURROUNDING PIGEON FORGE.

0615 AM     HAIL             2 SSE WALLAND           35.69N 83.80W
05/04/2021  M1.00 INCH       BLOUNT             TN   PUBLIC

0431 AM     HAIL             4 WSW OLIVER SPRINGS    36.00N 84.40W
05/04/2021  U0.50 INCH       ROANE              TN   PUBLIC

            REPORT FROM MPING: HALF-INCH (0.50 IN.).

0430 AM     HAIL             OLIVER SPRINGS          36.04N 84.34W
05/04/2021  E0.88 INCH       ANDERSON           TN   PUBLIC

            CORRECTS PREVIOUS HAIL REPORT FROM OLIVER
            SPRINGS. VIA SOCIAL MEDIA POST.

0912 PM     HAIL             3 SSE TALBOTT           36.12N 83.39W
05/03/2021  E0.50 INCH       JEFFERSON          TN   OFFICIAL NWS OBS

0908 PM     HAIL             1 N TALBOTT             36.17N 83.42W
05/03/2021  U0.50 INCH       HAMBLEN            TN   PUBLIC

            REPORT FROM MPING: HALF-INCH (0.50 IN.).

0858 PM     HAIL             1 S JEFFERSON CITY      36.10N 83.49W
05/03/2021  U0.50 INCH       JEFFERSON          TN   PUBLIC

            REPORT FROM MPING: HALF-INCH (0.50 IN.).

0237 PM     HAIL             GREENEVILLE             36.17N 82.82W
05/03/2021  U0.50 INCH       GREENE             TN   PUBLIC

            REPORT FROM MPING: HALF-INCH (0.50 IN.).

0225 PM     TSTM WND DMG     4 SW GREENEVILLE        36.12N 82.87W
05/03/2021                   GREENE             TN   LAW ENFORCEMENT

            COUPLE TREES DOWN ALONG WARRENSBURG ROAD.

0145 PM     HAIL             2 SW STRAWBERRY PLAINS  36.04N 83.71W
05/03/2021  M0.25 INCH       KNOX               TN   NWS EMPLOYEE

&&
Local storm report, May 4, 11:31 AM EDT, 35 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1131 AM EDT TUE MAY 4 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 AM     TSTM WND DMG     SEVIERVILLE             35.87N 83.57W
05/04/2021                   SEVIER             TN   911 CALL CENTER

            SEVERAL TREES DOWN IN THE SEVIERVILLE AREA.

&&
Special weather statement, May 4, 11:52 AM EDT, 14 minutes before
Special Weather Statement
National Weather Service Morristown TN
1152 AM EDT Tue May 4 2021

TNZ072-087-041630-
Blount Smoky Mountains TN-Southeast Monroe TN-
1152 AM EDT Tue May 4 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN BLOUNT AND
SOUTHEASTERN MONROE COUNTIES UNTIL 1230 PM EDT...

At 1152 AM EDT, Doppler radar was tracking a strong thunderstorm 9
miles west of Town Of Santeetlah, or 12 miles west of Robbinsville,
moving northeast at 40 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Smoky Mountains-Twentymile Creek, Smoky Mountains-Fontana Area,
Citico, Cades Cove and Deals Gap.

A Severe Thunderstorm Watch remains in effect until 200 PM EDT for
southwestern North Carolina...and east Tennessee.

LAT...LON 3535 8421 3565 8386 3566 8379 3557 8368
      3556 8377 3552 8383 3552 8387 3547 8392
      3545 8397 3541 8402 3537 8401 3535 8404
      3533 8403 3531 8404 3530 8402 3526 8408
TIME...MOT...LOC 1552Z 224DEG 34KT 3533 8403

BW
Special weather statement, May 4, 12:06 PM EDT, 0 minutes before
Special Weather Statement
National Weather Service Morristown TN
1206 PM EDT Tue May 4 2021

NCZ060-TNZ101-102-041630-
Cherokee NC-West Polk TN-East Polk TN-
1206 PM EDT Tue May 4 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CHEROKEE AND
SOUTHEASTERN POLK COUNTIES UNTIL 1230 PM EDT...

At 1205 PM EDT, Doppler radar was tracking a strong thunderstorm over
Blue Ridge, moving east at 50 mph.

Pea size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Murphy, Ducktown, William L. Davenport Refuge, Big Frog Mountain, Hot
House, Turtletown, Copperhill, Hiawasse Dam, Archville and Culberson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

A Severe Thunderstorm Watch remains in effect until 200 PM EDT for
southwestern North Carolina...and east Tennessee.

LAT...LON 3499 8463 3516 8464 3517 8402 3499 8400
TIME...MOT...LOC 1605Z 256DEG 46KT 3488 8437

BW

The office that day

Everything else NWS Morristown, TN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 3, 8:29 PM EDTSpecial Weather StatementMRXGreene, Unicoi, Washington46 min
May 3, 8:47 PM EDTSpecial Weather StatementMRXHamblen, Jefferson43 min
May 4, 3:10 AM EDTSevere Thunderstorm WarningMRXMorgan, Roane50 min
May 4, 3:53 AM EDTSevere Thunderstorm WarningMRXAnderson, Morgan, Roane52 min
May 4, 3:56 AM EDTSpecial Weather StatementMRXMorgan49 min
May 4, 4:12 AM EDTSpecial Weather StatementMRXMorgan48 min
May 4, 4:40 AM EDTSevere Thunderstorm WarningMRXAnderson, Knox30 min
May 4, 4:45 AM EDTSpecial Weather StatementMRXBlount45 min
May 4, 4:57 AM EDTAreal Flood AdvisoryMRXAnderson, Morgan, Roane3 hr
May 4, 5:14 AM EDTSpecial Weather StatementMRXKnox46 min
May 4, 5:34 AM EDTSpecial Weather StatementMRXBlount41 min
May 4, 6:05 AM EDTSevere Thunderstorm WarningMRXBlount, Sevier30 min
May 4, 6:11 AM EDTAreal Flood AdvisoryMRXAnderson, Knox3 hr
May 4, 6:16 AM EDTAreal Flood AdvisoryMRXBlount3 hr
May 4, 6:52 AM EDTSpecial Weather StatementMRXSevier53 min
May 4, 7:00 AM EDTFlash Flood WarningMRXBlount, Sevier3 hr
May 4, 7:24 AM EDTAreal Flood AdvisoryMRXScott3 hr
May 4, 7:58 AM EDTSpecial Weather StatementMRXCocke47 min
May 4, 9:05 AM EDTSpecial Weather StatementMRXMorgan, Scott40 min
May 4, 9:18 AM EDTSpecial Weather StatementMRXHamilton27 min
May 4, 9:37 AM EDTSevere Thunderstorm WarningMRXBledsoe, Morgan, Rhea, Roane38 min
May 4, 9:48 AM EDTSevere Thunderstorm WarningMRXBledsoe, Rhea27 min
May 4, 9:50 AM EDTSpecial Weather StatementMRXAnderson, Campbell, Claiborne, Union40 min
May 4, 9:53 AM EDTSpecial Weather StatementMRXHamilton, Marion, Sequatchie67 min
May 4, 10:03 AM EDTSevere Thunderstorm WarningMRXAnderson, Blount, Knox, Loudon, Roane13 min
May 4, 10:18 AM EDTSpecial Weather StatementMRXMcMinn, Meigs57 min
May 4, 10:24 AM EDTSpecial Weather StatementMRXBlount, Knox36 min
May 4, 10:37 AM EDTSpecial Weather StatementMRXHamblen38 min
May 4, 10:41 AM EDTSevere Thunderstorm WarningMRXBlount, Jefferson, Knox, Sevier34 min
May 4, 10:45 AM EDTSevere Thunderstorm WarningMRXBlount, Monroe30 min
May 4, 11:10 AM EDTSevere Thunderstorm WarningMRXCocke, Jefferson, Sevier22 min
May 4, 11:11 AM EDTFlash Flood WarningMRXHamilton, Marion, Sequatchie3 hr
May 4, 11:29 AM EDTAreal Flood WarningMRXBlount, Sevier6 hr
May 4, 11:44 AM EDTAreal Flood AdvisoryMRXBlount, Monroe2 hr
May 4, 11:47 AM EDTAreal Flood AdvisoryMRXBlount, Sevier118 min
May 4, 11:52 AM EDTSpecial Weather StatementMRXGraham38 min
May 4, 12:01 PM EDTFlash Flood WarningMRXCherokee, Clay3 hr

Nearby

Special Weather Statements in Tennessee, 2021Special Weather Statements in North Carolina, 2021Every special weather statement in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.