As Tropical Storm Irma moved north/northwest across the Florida Panhandle and southwest Georgia, gusty winds developed over the foothills and western Piedmont of North Carolina. While wind gusts rarely exceeded 40 mph in these areas, the combination of prolonged gusty winds and very wet soil from heavy rainfall caused quite a few trees to fall across the area, with trees down on homes in…
Every event with a place to put it; 5 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 GSP wrote it up.
As Tropical Storm Irma moved north/northwest across the Florida Panhandle and southwest Georgia, gusty winds developed over the foothills and western Piedmont of North Carolina. While wind gusts rarely exceeded 40 mph in these areas, the combination of prolonged gusty winds and very wet soil from heavy rainfall caused quite a few trees to fall across the area, with trees down on homes in Gastonia, Morganton, Mooresville, and Rockwell.
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 Greenville-Spartanburg, SC wrote its last area forecast discussion before the first event at Sep 11, 4:17 PM EST, 1 hour 43 minutes earlier.
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
517 PM EDT Mon Sep 11 2017
.SYNOPSIS...
Irma will accelerate northwestward through the southeast through
Wednesday. Wind and rain will increase across our region tonight and
then gradually taper off on Tuesday. The remnants of Irma will shift
back east over the mountains aided by an incoming cold front by
Thursday.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 515 PM EDT Monday: The effects of Irma have arrived into
northeast GA and the western Carolinas as multiple reports of
trees and power lines down have filtered into the office over
the last 20-30 mins. Currently per obs, the highest winds are
generally along/west of the I26 corridor, mainly focused over the
Lakelands and Upper Savannah River valley regions where gusts in
excess of 45-50mph have been reported, with a 51mph gust observed
at KAND recently. Further east the winds look to be picking us as
well were a few isolated reports of trees and power lines being
down have also been reported. Gusts closer to the I77 corridor
are less, however still potent at around 35-40mph. Am expecting
winds to gradually increase regionwide into the evening hours as
the center of Irma's circulation slides across GA. Overall think
that the tor threat is minimal this afternoon/evening as the warm
front remains to the south, likely not to move into the region
until near/after midnight, which by that time instability will be
at premium. That said, IF any spin ups did occur, it would be most
likely along/south of I85, and along/east of I77. As for precip,
dry air that was in place ahead of Irma really seems to be cutting
down on rates/accums as much time has been spent to moisten the
low lvls. With that, really not seeing any significant accums
across the area, with rates at generally around 1-2 tenths of an
inch per hour. As for the fcst, made adjustments to winds/t/td
and pops to align with recent coverage.
As of 230 PM EDT Monday: At the 2p update, the center of TS Irma was
about 50 mi SSE of Albany GA, moving NNW at 17mph. Strong 1027mb
surface high pressure centered over the Great Lakes continues
to wedge down the Eastern Seaboard in a classic CAD scenario.
Temperatures have been really really slow to increase, and have been
playing catchup all day to decrease them and decrease them again.
Ended up with a non-diurnal trend with temperatures remaining
fairly steady through the afternoon, slowly warming this evening as
this frontal feature moves north and the damming begins to erode.
Temperatures at sunrise are expected several degrees warmer than
they are right now, with a continued warming trend into tomorrow.
Winds can be kind of breezy in damming anyway, but add to it the
pressure gradient squeezed between the high and Irma, and the
winds are starting to rock a little out there. Our peak wind here
at GSP was 37kt (43mph), just as I've been typing this, and we've
seen several reports between 35-40kt across the Upstate (and in
the mountains, currently gusting 56mph at Mt. Mitchell). Increasing
reports of trees down across the area, and this will continue as the
winds pick up. Concerning part is that winds in Atlanta and areas
south have been trending a little higher than forecast, and just
in the past hour Anderson reported a 48mph wind gusts, also higher
than the forecast. Across most of the Upstate (including here at
the WFO), the forecast is actually doing pretty well. Expect winds
to continue to ramp up over the next few hours, peaking somewhere
between 21-00z across most of the area, but remaining strong through
the early part of the overnight hours as the gradient remains
fairly unchanged until after 06z. Expect a fairly rapid decrease
after 12z as the remnants of Irma move into N AL. With all this,
plan no changes to the High Wind Warning or Wind Advisories (that
is, in addition to the update from this morning). Of course, might
still see some changes in a couple of hours with the 5pm TCM update.
Next up...rainfall. Storm total amounts so far have been pretty
light, as the low level atmosphere has been slow to saturate after
days of a cool dry airmass in place. Radar/gauge biases this
morning have ranged from 0.5-0.6, indicating that the radar is
overestimating (we basically multiply the accumulation by the bias
to get the bias-adjusted amount). Still expect rain to continue
to pick up through the evening/night and moisture should continue
to pool up against the Blue Ridge, so current Flash Flood Watch
looks okay for right now. PW values hovering just below 2" for
much of our Piedmont areas this evening and then slowly decreasing
thereafter. Biggest problem would be with any training cells,
but with the low- level stable air, it's gonna be hard to get
enhanced cells. Overall, for 36-hr period starting 00z tonight,
looking like ~1.5" for most of the area, creeping up to 2" in
the foothills and 2.5-3" in the mountains especially along the
escarpment (note this does NOT include what has fallen already and
will fall between now and 00z). Wording in the Flash Flood Watch
still looks good. Should see some lingering light precip across
the area, especially in the mountains through the day tomorrow.
We've already discussed the low-level stable air, with a pretty
good inversion at about 850mb. This inversion is just awesome
because the winds aloft are really screaming up there; 925mb winds
of 50-60kt and 850mb easily 70kt. Winds are interesting enough
but without that inversion in place we could be looking at some
serious issues. Above that inversion, however, some MUCAPE should
be realized, and there is the chance that some SBCAPE could creep
up into the region tonight, spreading north from about 03z in
southern zones, approaching the SC/NC state line around 09z, and
continuing north through early Tuesday. Shear is really phenomenal
with 40-60kt 0-6km shear early on, decreasing to 40kt as the warm
frontal feature/wedge front lifts N. Chances of TC tors remains
fairly low still, but certainly non-zero, and will have to be
watched through the night.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 200 PM EDT Monday: The remnants of Irma should be a tropical
depression over western TN/northern MS by 00Z Wednesday. While
moisture will not be entirely absent from the area, a slot of drier
air will be in the process of squeezing into our area from the south
as the last of Irma's influence departs to the west. A few showers
may linger through the early evening hours before a brief drying
period commences. The pressure gradient (and associated gradient
winds) will lessen significantly by this time. Irma will become a
remnant low on Wednesday as it is absorbed into the upper mean flow
and transported quickly eastward.
Though Irma's remnants will have lost the deep tropical moisture
source by this point, southerly flow and height falls associated
with Irma's remnants will provide moisture and forcing for some
light rain across our area. Showers will spread from west to east on
Wednesday and will linger into Thursday, so chance pops are
maintained through the end of the short term period Thursday
evening. Instability looks to be minimal at this time, and thunder
mention is almost nonexistent. Because of the lack of a substantial
deep tropical moisture source, QPF will remain generally low, with
issues not expected at this time.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 200 PM EDT Monday: By 00Z Friday, the lingering remnants of
the upper low formerly known as Irma will be moving rapidly
northeastward out of our area, with slight chance pops lingering
overnight and into early Friday morning. Heights will progressively
rise at this point, increasing temperatures and beginning a slight
drying trend. A weak remnant boundary associated with higher
moisture will remain over the southeast Friday, allowing chances for
diurnal convection to return each afternoon through the weekend.
With upper height rises forecast through the period, temperatures
will moderate back to normal through the end of the medium range.
There is a large amount of uncertainty with the track of Jose at the
moment, and whether or not it may get close enough to our area for
the outer circulation to increase moisture in our area early next
week. Models have shown extremely poor agreement and extremely poor
run-to-run consistency, so judgment on the influence of Jose
anywhere in the southeast next week will be reserved at this time.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
At KCLT and Elsewhere: Conditions continue to deteriorate across the
area with MVFR cigs spreading up from the S but haven't reached the
NC TAFs yet. Expect widespread MVFR this evening dropping to IFR
during the late overnight period. Should see slow improvement from S
to N Tuesday morning, but current TAFs keep all sites MVFR through
the end of the period. VSBY will be in and out, dropping to IFR or
lower in heavier rainbands and +SHRA, with possibly VFR with the
lighter -SHRA. As for winds, strong NE winds will continue, slowly
veering around to ESE through the end of the period. Strong gradient
between Irma's remnants and surface high to the NE will allow gusts
easily 30-40kt through the evening (peak looks to be around 00z) but
still gusty through the night, subsiding somewhat around 12z. Very
strong winds aloft will lead to intermittent LLWS issues and have
kept them through about 12z at all TAF sites. Isolated TSRA not out
of the question but best chance looks at KCLT early Tue AM.
Outlook: Conditions slowly improve Tuesday but a chance of
convection remains especially across the mountains. Scattered
generally diurnal convection chances continue through the week.
Morning mountain valley fog/stratus also possible.
Confidence Table...
21-03z 03-09Z 09-15Z 15-18Z
KCLT High 88% High 91% High 88% High 92%
KGSP High 100% High 95% High 86% High 100%
KAVL Med 74% High 90% Med 60% High 96%
KHKY Med 67% High 85% High 87% Med 76%
KGMU High 100% High 86% High 90% High 100%
KAND High 98% High 100% High 88% High 94%
The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:
www.weather.gov/gsp/aviation
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...High Wind Warning until 2 AM EDT Tuesday for GAZ010-017-018-
026-028-029.
Flash Flood Watch through Tuesday morning for GAZ010-017-018-
026-028-029.
Wind Advisory from 2 AM to 4 AM EDT Tuesday for GAZ010-017-018-
026-028-029.
NC...Wind Advisory until 4 AM EDT Tuesday for NCZ033-035>037-
048>053-056>058-069>072-082-501>506.
High Wind Warning until 2 AM EDT Tuesday for NCZ059-062>065-
068-507>510.
Flash Flood Watch through Tuesday morning for NCZ063>065-505-
507-509.
Wind Advisory from 2 AM to 4 AM EDT Tuesday for NCZ059-062>065-
068-507>510.
SC...Wind Advisory until 4 AM EDT Tuesday for SCZ009-014.
High Wind Warning until 2 AM EDT Tuesday for SCZ001>008-
010>013-019.
Flash Flood Watch through Tuesday morning for SCZ001.
Wind Advisory from 2 AM to 4 AM EDT Tuesday for SCZ001>008-
010>013-019.
&&
SYNOPSIS...Carroll
NEAR TERM...CDG/TDP
SHORT TERM...Carroll
LONG TERM...Carroll
AVIATION...TDPHazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 434 AM EDT Mon Sep 11 2017 NCZ059-062-068-508-510-SCZ002>008-010>013-019-120845- Northern Jackson-Macon-Cleveland-Greater Rutherford-Eastern Polk- Pickens Mountains-Greenville Mountains-Greater Oconee- Greater Pickens-Greater Greenville-Spartanburg-Cherokee-Anderson- Abbeville-Laurens-Union-Greenwood- 434 AM EDT Mon Sep 11 2017 ...HIGH WIND WARNING IN EFFECT UNTIL 2 AM EDT TUESDAY... This Hazardous Weather Outlook is for Northeast Georgia, western upstate South Carolina, and adjoining counties in North Carolina. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. In addition to the wind hazards, locally excessive rainfall and isolated tornadoes will be possible, especially this evening. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. ..Tuesday...Tropical Storm hazards possible. Irma will move away from our area and further weaken over the course of the day, but flash flood and wind threats still will exist in our area through mid-morning. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. ..Friday...No hazardous weather is expected at this time. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. NCZ033-035>037-048>053-056>058-069>072-082-501>504-506-SCZ009-014- 120845- Avery-Alexander-Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood- Buncombe-Catawba-Rowan-Graham-Lincoln-Gaston-Mecklenburg-Cabarrus- Union-Caldwell Mountains-Greater Caldwell-Burke Mountains- Greater Burke-Eastern McDowell-York-Chester- 434 AM EDT Mon Sep 11 2017 ...WIND ADVISORY IN EFFECT UNTIL 4 AM EDT TUESDAY... This Hazardous Weather Outlook is for the mountains and Interstate 40 corridor of Western North Carolina, and the greater Charlotte area of both North and South Carolina. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Wind Advisory. In addition to the wind hazards, locally excessive rainfall and isolated tornadoes will be possible, especially this evening. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. ..Tuesday...Tropical Storm hazards possible. Irma will move away from our area and further weaken over the course of the day, but flash flood and wind threats still will exist in our area through mid-morning. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. ..Friday...No hazardous weather is expected at this time. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. GAZ010-017-018-026-028-029-NCZ063>065-507-509-SCZ001-120845- Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Southern Jackson- Transylvania-Henderson-Rutherford Mountains-Polk Mountains- Oconee Mountains- 434 AM EDT Mon Sep 11 2017 ...HIGH WIND WARNING IN EFFECT UNTIL 2 AM EDT TUESDAY... ...FLASH FLOOD WATCH IN EFFECT THROUGH TUESDAY MORNING... This Hazardous Weather Outlook is for Northeast Georgia, the mountainous portion of Oconee County South Carolina, and the Blue Ridge section of southwest North Carolina. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. High Wind Warning. Flash Flood Watch. In addition to these hazards, isolated tornadoes will be possible, especially this evening. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. ..Tuesday...Tropical Storm hazards possible. Irma will move away from our area and further weaken over the course of the day, but flash flood and wind threats still will exist in our area through mid-morning. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. ..Friday...No hazardous weather is expected at this time. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. NCZ505-120845- McDowell Mountains- 434 AM EDT Mon Sep 11 2017 ...WIND ADVISORY IN EFFECT UNTIL 4 AM EDT TUESDAY... ...FLASH FLOOD WATCH IN EFFECT THROUGH TUESDAY MORNING... This Hazardous Weather Outlook is for the mountainous portion of McDowell County North Carolina. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov on the Internet for more information about the following hazards. Flash Flood Watch. Wind Advisory. In addition to these hazards, isolated tornadoes will be possible, especially this evening. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. ..Tuesday...Tropical Storm hazards possible. Irma will move away from our area and further weaken over the course of the day, but flash flood and wind threats still will exist in our area through mid-morning. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. ..Friday...No hazardous weather is expected at this time. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. Wimberley
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
454 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0451 PM TROPICAL STORM 2 N SIMPSONVILLE 34.76N 82.26W
09/11/2017 GREENVILLE SC TRAINED SPOTTER
TREE DOWN
&&
SWILKINSPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
457 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0457 PM TROPICAL STORM 2 NE SHELBY 35.31N 81.52W
09/11/2017 CLEVELAND NC LAW ENFORCEMENT
A TREE AND POWER LINE DOWN.
&&
SWILKINSPRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
459 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0457 PM TROPICAL STORM 2 NE SHELBY 35.31N 81.52W
09/11/2017 CLEVELAND NC BROADCAST MEDIA
A TREE AND POWER LINE DOWN.
&&
SWILKINSPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
502 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0454 PM TROPICAL STORM FORT MILL 35.01N 80.94W
09/11/2017 YORK SC LAW ENFORCEMENT
2 TREES DOWN ON ROADS IN TOWN.
&&
SWILKINSPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
528 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0527 PM TROPICAL STORM 2 N SIMPSONVILLE 34.76N 82.26W
09/11/2017 GREENVILLE SC SOCIAL MEDIA
LARGE TREE DOWN.
&&
BMARTINPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
607 PM EDT MON SEP 11 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0527 PM TROPICAL STORM ELLENBORO 35.33N 81.76W
09/11/2017 RUTHERFORD NC BROADCAST MEDIA
DOWNED TREE
0550 PM TROPICAL STORM GROVER 35.17N 81.45W
09/11/2017 CLEVELAND NC BROADCAST MEDIA
TREE DOWN.
&&
BMARTINThe national radar mosaic for the moment the first event began.
5 strong wind. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Carolina in 2017Every state in 2017This day in weather historyWarnings in North Carolina, September 2017
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: 722078, 722079, 722080, 722081, 722082.