Daytime heating and a weak upper impulse resulted in a few strong thunderstorms.
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 CAE wrote it up.
Daytime heating and a weak upper impulse resulted in a few strong thunderstorms.
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 Columbia, SC wrote its last area forecast discussion before the first event at May 12, 1:52 PM EST, 1 hour 43 minutes earlier.
Area Forecast Discussion National Weather Service Columbia SC 252 PM EDT Sat May 12 2018 .SYNOPSIS... Bermuda high pressure will ridge into the Southeastern States over the weekend, producing mainly dry weather and above normal temperatures. Surface low pressure will develop in the Gulf of Mexico and move into the region early next week, bringing an increased chance for showers and thunderstorms with cooler temperatures. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Upper ridge has become centered over the southern part of the country as surface high pressure remains anchored off the east coast. Temperatures are pushing into the mid 90s early this afternoon and think we there is a reasonable chance at tying or breaking the record high at AGS with a few more hours of heating left. Moderate instability has developed with a few showers starting to appear on radar with the strong solar insolation with low level lapse rates over 8 C/km and Lifted Index values around -4C to -5C. There is some weak shortwave energy over the area that may help offset the broad subsidence from the upper ridge and expect isolated to scattered convection to develop. Although probability of severe weather remains low, it cannot be ruled out, and prominent inverted-V signature on soundings indicate any storms that develop will be capable of gusty outflows. Will continue with 20 pops for now. Sea breeze could be active this afternoon into evening as well given strong surface heating and may affect the eastern Midlands into the evening. Any lingering convection this evening should diminish after sunset with loss of heating. Some lingering debris clouds should also dissipate overnight yielding mostly clear skies by morning. Overnight lows expected to again be mild in the mid 60s. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... Sunday, expect another warm day with near record heat, highs will be in the mid-90s. Increasing upper level clouds to our south may keep temperatures a few degrees cooler across the southern FA. A mid- level capping inversion will hinder convective development and likely prevent any showers or thunderstorms. Lows overnight will be in the mid to upper 60s. Monday, low surface pressure in the Gulf of Mexico will move slowly northward. The ridge over the forecast area will weaken through the day but the subsidence and capping inversion should prevent showers for much of the area until late in the day. There will be a chance of showers and thunderstorms late Monday afternoon but the deepest moisture will remain south of the area. Highs will be cooler, in the low 90s, due to the increasing cloud coverage. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... The long term weather pattern remains unsettled with at least a chance of rain each day. The surface low will continue moving northward, into the Gulf Coast States, bringing deep moisture into the Southeast. The strongest moisture advection and most likely chance for moderate rainfall appears to be Tuesday and Wednesday. Ensemble and deterministic guidance suggests numerous showers and thunderstorms. Warm, moist advection continues across the Southeast through the remainder of the period. There will be at least a chance of showers and thunderstorms through the rest of the long term. High temperatures will be closer to normal for the rest of the long term with cloud cover and precip expected. Low temperatures will be above normal throughout the long term. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... VFR conditions expected through the TAF period. High pressure will remain over the region through the TAF period. Diurnal cumulus has developed and expect scattered convection later this afternoon so have included VCSH at all terminals expect OGB after 19z. Will amend for thunder due to uncertainty in exactly where storms may form. Any convection should diminish this evening with VFR conditions expected. Winds have been light and variable with the surface trough in the area and winds will become light to calm overnight. With little change in the air mass today the potential for fog to develop overnight should be low. .EXTENDED AVIATION OUTLOOK... Restrictions possible Monday afternoon through Wednesday in showers and thunderstorms. && .CLIMATE... Record high temperatures Today/Sun CAE...97/97 AGS...94/97 && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. &&
Hazardous Weather Outlook National Weather Service Columbia SC 337 AM EDT Sat May 12 2018 GAZ040-063>065-077-SCZ015-016-018-020>022-025>031-035>038-041-130745- Lincoln-McDuffie-Columbia-Richmond-Burke-Lancaster-Chesterfield- McCormick-Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington- Richland-Lee-Aiken-Sumter-Barnwell-Orangeburg-Calhoun-Clarendon- Bamberg- 337 AM EDT Sat May 12 2018 This Hazardous Weather Outlook is for the Midlands of South Carolina and the Central Savannah River area of Georgia. .DAY ONE...Today and Tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Sunday through Friday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
Special Weather Statement
National Weather Service Columbia SC
256 PM EDT SAT MAY 12 2018
SCZ037-121945-
Calhoun SC-
256 PM EDT SAT MAY 12 2018
...Strong Thunderstorms Will Impact Portions of central Calhoun
County Until 345 PM EDT....
At 256 PM EDT...National Weather Service doppler radar indicated a
strong thunderstorm 7 miles northwest of St. Matthews, or 15 miles
north of Brookdale, moving southeast at 5 mph.
HAZARD...gusty winds 40 to 50 mph.
IMPACT...expect minor damage to tree limbs and blowing around of
light, unsecured objects.
Some locations in the path of this storm include...
St. Matthews.
This includes Interstate 26 between mile markers 131 and 140.
LAT...LON 3374 8069 3361 8085 3362 8088 3373 8096
3380 8087 3379 8084 3377 8082 3378 8081
3376 8078 3377 8077 3377 8076
TIME...MOT...LOC 1856Z 312DEG 6KT 3373 8087
HCSpecial Weather Statement
National Weather Service Columbia SC
425 PM EDT SAT MAY 12 2018
GAZ064-065-122115-
Richmond GA-Columbia GA-
425 PM EDT SAT MAY 12 2018
...Strong Thunderstorms Will Impact Portions of central Richmond and
southeastern Columbia Counties Until 515 PM EDT....
At 425 PM EDT...National Weather Service doppler radar indicated a
strong thunderstorm near Fort Gordon. This storm was nearly
stationary.
HAZARD...strong winds 45 to 55 mph and pea sized hail.
IMPACT...expect minor damage to tree limbs and blowing around of
light, unsecured objects. Minor hail damage to plants,
trees and crops is possible. Damage to windshields is
unlikely.
Some locations in the path of this storm include...
Grovetown, Evans, Augusta, Martinez and Fort Gordon.
This includes the following highways...
Interstate 20 in Georgia between mile markers 189 and 200.
Interstate 520 in Georgia between mile markers 1 and 13.
LAT...LON 3333 8213 3349 8222 3356 8206 3342 8193
TIME...MOT...LOC 2025Z 089DEG 0KT 3345 8210The Columbia radar (KCAE), 106 km away, was scanning. The volume nearest the first event began at 20:35 UTC.
3 hail. Local standard time, as filed.
Trained SKYWARN spotter reported penny size hail on Wrightsboro Rd at Flowing Wells Rd. Time estimated.
An mPING report of one half inch hail.
An mPING report of pea size hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Georgia in 2018Every state in 2018This day in weather historyWarnings in Georgia, May 2018
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: 759404, 759405, 759406.