A cold front dropped southward into a hot and humid airmass over central Pennsylvania, generating scattered showers and thunderstorms in a high CAPE, low shear environment. Wind damage was reported with a single storm cell that developed well ahead of the front in the vicinity of Danville.
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 CTP wrote it up.
A cold front dropped southward into a hot and humid airmass over central Pennsylvania, generating scattered showers and thunderstorms in a high CAPE, low shear environment. Wind damage was reported with a single storm cell that developed well ahead of the front in the vicinity of Danville.
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 State College, PA wrote its last area forecast discussion before the first event at Jun 18, 11:06 AM EST, 1 hour 54 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 1206 PM EDT Mon Jun 18 2018 .SYNOPSIS... Heat and humidity will be broken by a cold front dropping down from the north tonight. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Well-advertised high heat/humidity (for PA) will peak today. Even if the heat index is a deg or two lower than we have been playing up, it will still be uncomfortable, and in some dangerous for age groups most susceptible to the heat. Convective initiation is along the leading edge of the Lake Erie breeze across Erie and NW Warren County attm. We expect this area of showers and TSRA to slowly strengthen as it moves inland into increasing cape this afternoon. Second area of convection based on the latest CAMS guidance will be INVOF a lee trough across the Susq Valley and points just to the west. The instability is quite high due to the low 70 dewpoints and hot temps. Even though this will generate lots of tall clouds, they may get strangled (turkey towers) by the warm temps aloft (8-9C at 700 mb). PWAT will be above 1.5" all day, but the approach of the front tonight and moisture flow/pooling ahead of it will push it above 2" in the north before sunset. Therefore, any TSRA that form could dump some heavy rainfall amounts of up to one inch in just 20-30 minutes. Although an isolated thunderstorm could pop up well ahead of the best forcing arriving with the cold front from the north very late today and tonight, some CIN exists in the low levels and the air is very warm aloft. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... SPC MRGL risk of severe is painted into the northern half of the area for storms this evening and tonight. MU CAPE of 2000-2500J are the mean in the HREF solutions from 00Z. Most likely threat of severe wx will be strong wind gusts. The PWATs mean there could also be heavy rain. The storms should be moving along, though. Best bulk shear will be in the evening N and just after midnight S. The driest air won't get shoved in from the northeast until late tonight, so storms/showers may linger in the SW all night. Since the front won't be moving too far from the SW corner of the state, there will still be some showers/storms on Tuesday in the SW. Temps and dewpoints will be much lower in the NE half to two-thirds of the area, but the SW/SC may be just as muggy as they are today - but likely cooler. Dewpoints back in the m50s on Tues aftn in the N will feel much better. The push of dry air continues and almost everywhere will be below 60 by Midnight Tues night. Most of the showers should be shunted off to our SW for Tuesday night. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... Where the front stalls (or if it bubbles back to the north) will determine our weather for the second half of the work week. By Thu/Fri, building high pressure over the northeastern U.S. should push any lingering showers south of the area. However, as this high pulls off the East Coast next weekend, returning southerly flow will bring moisture and a renewed chance of unsettled weather northward into the area. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... High pressure along the east coast will supply mainly VFR conditions and just a 7-10 kt west to southwest wind for much of the time across central Pa today. Vertical mixing/extension of the boundary layer up to 6-7 kt today will tap winds in the mid to upper teens (kts) and transport much of that momentum down to the surface in gusts into the mid teens through this afternoon. A few...mainly scattered afternoon thunderstorms are possible across northern Pa (and to a lesser extent over the Susquehanna Valley) this afternoon. However, the odds of a brief vis reduction are quite low outside of KBFD. There is a better chance of brief thunderstorms impacts across the northern tier later this evening associated with the arrival of a cold front. .Outlook... Tue...Early AM low cigs possible KBFD/KJST. Wed...Showers/cig reductions possible southern Pa. Thu...No sig wx expected. Fri...PM showers/cig reductions possible central mountains. && .CLIMATE... Record max temperatures for June 18th: Harrisburg: 97 in 1957 Williamsport: 97 in 1994 Altoona: 92 in 1994 Bradford: 87 in 1994 State College: 94 in 1923 && .CTP WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM EDT this evening for PAZ027-028-036- 049>053-056>059-063>066. && SYNOPSIS...Dangelo/Lambert NEAR TERM...Dangelo/Lambert SHORT TERM...Dangelo LONG TERM...Evanego AVIATION...Lambert/Gartner CLIMATE...Lambert
Hazardous Weather Outlook National Weather Service State College PA 412 AM EDT Mon Jun 18 2018 PAZ027-028-036-056-057-059-063>066-190815- Mifflin-Juniata-Franklin-Perry-Dauphin-Lebanon-Cumberland-Adams-York- Lancaster- 412 AM EDT Mon Jun 18 2018 ...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS EVENING... This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov/StateCollege on the internet for more information about the following hazards. Heat Advisory. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ024>026-033>035-190815- Cambria-Blair-Huntingdon-Somerset-Bedford-Fulton- 412 AM EDT Mon Jun 18 2018 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ004>006-010>012-017>019-037-041-042-045-046-190815- Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield- Northern Centre-Southern Centre-Tioga-Northern Lycoming-Sullivan- Southern Clinton-Southern Lycoming- 412 AM EDT Mon Jun 18 2018 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. A few strong to severe thunderstorms with gusty winds are possible tonight. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ049>053-058-190815- Union-Snyder-Montour-Northumberland-Columbia-Schuylkill- 412 AM EDT Mon Jun 18 2018 ...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS EVENING... This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. Please listen to NOAA Weather Radio or go to weather.gov/StateCollege on the internet for more information about the following hazards. Heat Advisory. A few strong to severe thunderstorms with gusty winds are also possible tonight. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather.
Special Weather Statement
National Weather Service State College PA
1143 AM EDT MON JUN 18 2018
PAZ004-181630-
Warren PA-
1143 AM EDT MON JUN 18 2018
...SPECIAL WEATHER STATEMENT...
At 1143 AM EDT, Doppler radar indicated a strong thunderstorm over
Clymer, moving east at 35 mph.
Pea size hail and winds in excess of 30 mph are possible.
Locations impacted include...
Warren, Columbus, Youngsville, Russell, Spring Creek, Scandia,
Lottsville, Sugar Grove, Starbrick and Bear Lake.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
&&
LAT...LON 4200 7892 4185 7892 4183 7961 4199 7961
4200 7950
TIME...MOT...LOC 1543Z 267DEG 29KT 4198 7961
LambertSpecial Weather Statement
National Weather Service State College PA
1236 PM EDT MON JUN 18 2018
PAZ004-005-010-181730-
McKean PA-Warren PA-Elk PA-
1236 PM EDT MON JUN 18 2018
...STRONG THUNDERSTORMS WILL AFFECT PARTS OF ELK...WARREN...AND
MCKEAN COUNTIES UNTIL 130 PM EDT...
At 1227 PM EDT, Doppler radar indicated strong thunderstorms along a
line extending from near Allegany State Park to near Warren to near
Spring Creek to near Enterprise. Movement was east at 45 mph.
Dime size hail and winds in excess of 40 mph are possible.
Strong thunderstorms will be near...
Russell around 1230 PM EDT.
Bradford and Scandia around 1235 PM EDT.
Warren and Chapman State Park around 1245 PM EDT.
Warren South around 1250 PM EDT.
Marshburg and Kinzua Dam around 1255 PM EDT.
Sheffield around 105 PM EDT.
Other locations impacted by these storms include Tidioute, Starbrick,
Sugar Grove, Eldred and Bear Lake.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
Persons in campgrounds should consider seeking sturdy shelter until
these storms pass.
&&
LAT...LON 4200 7821 4182 7821 4181 7833 4148 7871
4151 7896 4162 7896 4163 7961 4200 7961
TIME...MOT...LOC 1627Z 273DEG 39KT 4199 7875 4189 7916 4187 7944 4167
7958
LambertSpecial Weather Statement
National Weather Service State College PA
132 PM EDT MON JUN 18 2018
PAZ051>053-181830-
Columbia PA-Northumberland PA-Montour PA-
132 PM EDT MON JUN 18 2018
...A STRONG THUNDERSTORM WILL AFFECT PARTS OF NORTHUMBERLAND...
MONTOUR...AND COLUMBIA COUNTIES UNTIL 230 PM EDT...
At 132 PM EDT, Doppler radar indicated a strong thunderstorm over
Mooresburg, moving east at 20 mph.
Dime size hail and winds in excess of 40 mph are possible.
Locations impacted include...
Bloomsburg, Berwick, Danville, Elysburg, Riverside, Catawissa,
Mifflinville, Lightstreet, Almedia, Fernville, Mechanicsville,
Buckhorn, Aristes, Numidia, Rupert, Slabtown, Mainville, Mooresburg,
Shumans and Knoebels Grove.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.
&&
LAT...LON 4089 7628 4081 7631 4091 7675 4101 7680
4107 7671 4105 7623 4095 7621
TIME...MOT...LOC 1732Z 276DEG 16KT 4099 7666
LambertThe State College radar (KCCX), 113 km away, was scanning. The volume nearest the first event began at 17:58 UTC.
7 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees onto Route 11 in Point Township.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees along Route 11 in Mahoning Township east of Danville.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires along Route 426 near Garland.
A severe thunderstorm producing winds estimated near 60 mph knocked down a tree onto a home along Route 6 near Youngsville.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires along Route 62.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees onto wires along Cherry Grove Road.
A severe thunderstorm producing winds estimated near 60 mph knocked down a tree across a roadway near Wilcox.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2018Every state in 2018This day in weather historyWarnings in Pennsylvania, June 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: 751906, 751907, 751908, 751909, 751910, 751911, 751912.