Scattered showers and pulse thunderstorms developed in a very warm and humid airmass over central Pennsylvania. Anomalously high PWATs resulted in very heavy rainfall in some storms, and a few reports of wind damage were received.
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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.
Scattered showers and pulse thunderstorms developed in a very warm and humid airmass over central Pennsylvania. Anomalously high PWATs resulted in very heavy rainfall in some storms, and a few reports of wind damage were received.
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 Jul 4, 10:28 AM EST, 1 hour 2 minutes earlier.
Area Forecast Discussion National Weather Service State College PA 1128 AM EDT Wed Jul 4 2018 .SYNOPSIS... Heat and humidity will continue through at least Friday morning before a cold front pushes Souheast through the region late Thursday into early Friday. Scattered to numerous thunderstorms with locally heavy downpours are possible this afternoon and again Thursday before the cold front generates widespread storms Thursday night. Cooler and less humid air moving in behind the cold front will last all weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A wavy, quasi-stnry low-level frontal boundary over the northern tier of PA late this morning has fired and maintained rather deep updrafts (and slow, very heavy rain producing TSRA) during the otherwise convective min period of the day. Recently issued a FLash Flood Watch for 5 of our Northern Tier Counties through 03Z Thu, and WPC followed up by upgrading their Day 1 ERO to a Slight Risk for approx the NE third of PA. Localized radar estimates of around 3 inches within a 90 minute period have occurred across portions of Potter and Mckean Counties over the past few hours and have been covered with Flood Advisories so far, as the new convective development has been sagging slowly to SSE along the still relatively tight outflow boundaries. The best cape begins to focus across Central PA and the Laurel Highlands this afternoon and some near term high res models show a distinct, elongated cold pool just south of I-80 at 21Z today in response to the deep convection initiated along the slowly drifting front/outflow boundary from the present late morning convection up north. PWATs off the 04/14Z RAP are at, or slightly above 2 inches across the entire CWA, so any locations that sees training TSRA could pick up a quick 1-2.5 inches of rain within an hour and experience at least minor flooding concerns. May need to extend the FlasH Flood Watch further south based on upcoming CAMs runs. Temps and apparent temps will tickle heat Advisory Criteria once again across our SE zones. However, more in the way of clouds than recent days with scattered-areas of more widespread convection will trim max temps in most places to the mid-upper 80s across the southern valleys, and low-mid 80s elsewhere. Therefore, we will stay away from a heat advy at this point. But, further collaboration and thought could change this course. Main point for an advy is that a great percentage of people will be outdoors at some point today, and should be aware of the dangers of the heat and humidity. An advy might keep it in their mind to take precautions to protect against heat-related illness. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... As the preponderance of guidance has seemed to indicate over the last few days, we should see lots of the convection die down in the early evening. This would bode well for many fireworks displays. However, some storms will linger like this evening. Again, overall coverage will make it very difficult to tell anyone that it will not rain on their specific display at 9 PM. But, will drop PoPs from likely (60) to low chance (30) percentages at 8 PM (00Z). NAM and GFS both push the last of the convection out to the fringes of the CWA during the early evening. But, the CAMs keep some in the middle of the CWA then. Will keep with the operational guidance and consistency on this matter. The rest of the night seems dry. A mention of fog is not a bad idea, either. Persistence is a friend in stretches like this. The sfc wind becomes more SWrly in the west for the day on Thursday and should help to focus some increase in moisture there. A lake breeze in the NW and the terrain elsewhere along the Alleghenies could provide focal points for convection. Upper heights slowly lower a few decameters thru the day and Thursday night as a weak pre-frontal trough moves in from the NW. So, it should be easier to get more convection going. Day2 outlook from SPC does indicate that slightly stronger winds aloft on Thurs PM could support isolated wind damage. Thursday night looks very disorganized, but could be the time to put the highest PoPs in for the NW half of the area. The front nears the NW around 12Z Fri, and moves through with some alacrity on Friday morning. All guidance pushes the front thru all but the far SE by the middle of the afternoon. Therefore, it would be tough to see strong convection without the benefit of daytime/peak heating for all but the SE on Friday. But, the PoPs should be OK at categorical for the morning and early aftn for the central and srn zones. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... *Cooler and less humid air will arrive this weekend The cold front should be well to our south at 00Z Sat. Drier and There is some question as to how much upper ridging can rebound into early next week. Relief from the relentlessly hot/humid weather will arrive this weekend as cooler and less humid air sweeps southeast from Canada. Showers may drop in from the Great Lakes in mid-week, but Sat- Mon look dry with seasonable temps. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... A few showers and storms across the far north since 6 AM. Mention Thunder in the BFD TAF. 12Z TAFS sent. Earlier discussion below. Any early morning fog will mix out by late morning. Focus will then shift toward scattered afternoon and evening thunderstorms, which could produce a brief vis reduction in spots. .Outlook... Thu...Patchy AM fog possible. Isolated PM thunderstorm impacts possible, mainly northwest Pa. Fri...Shower or thunderstorm impacts possible, mainly in the morning. Sat-Sun...No sig wx expected. && .CTP WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through this evening for PAZ005-006-037-041- 042. && SYNOPSIS...Lambert NEAR TERM...Lambert SHORT TERM...Dangelo LONG TERM...Gartner/Steinbugl AVIATION...Martin
Hazardous Weather Outlook National Weather Service State College PA 1003 AM EDT Wed Jul 4 2018 PAZ004-010>012-017>019-024>028-033>036-045-046-049>053-056>059- 063>066-051415- Warren-Elk-Cameron-Northern Clinton-Clearfield-Northern Centre- Southern Centre-Cambria-Blair-Huntingdon-Mifflin-Juniata-Somerset- Bedford-Fulton-Franklin-Southern Clinton-Southern Lycoming-Union- Snyder-Montour-Northumberland-Columbia-Perry-Dauphin-Schuylkill- Lebanon-Cumberland-Adams-York-Lancaster- 1003 AM EDT Wed Jul 4 2018 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and Tonight. Isolated, strong and slow moving thunderstorms could produce locally very heavy rainfall amounts of over an inch in just 30 to 60 minutes this afternoon and evening. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Scattered strong to possibly severe thunderstorms will precede and accompany the passage of a cold front Thursday afternoon into early Thursday night. Locally very heavy rainfall is also possible in areas receiving a few thunderstorms over a short time period. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ005-006-037-041-042-051415- McKean-Potter-Tioga-Northern Lycoming-Sullivan- 1003 AM EDT Wed Jul 4 2018 ...FLASH FLOOD WATCH IN EFFECT THROUGH 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. Flash Flood Watch. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Scattered strong to possibly severe thunderstorms will precede and accompany the passage of a cold front Thursday afternoon and evening. Locally very heavy rainfall is also possible in areas receiving a few thunderstorms over a short time period. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. Lambert
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1159 AM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1153 AM HEAVY RAIN ULYSSES 41.90N 77.76W
07/04/2018 E2.50 INCH POTTER PA 911 CALL CENTER
WATER OVER PUSHERSIDING ROAD CLOSED ROAD TEMPORARILY.
&&
EVENT NUMBER CTP1801951
PAHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1205 PM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1106 AM HEAVY RAIN ANDREWS SETTLEMENT 41.90N 77.90W
07/04/2018 E2.50 INCH POTTER PA 911 CALL CENTER
WATER OVER PEET BROOK ROAD
&&
EVENT NUMBER CTP1801952
PAHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1208 PM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1117 AM HEAVY RAIN 3 W GALETON 41.73N 77.70W
07/04/2018 E2.50 INCH POTTER PA 911 CALL CENTER
WATER FLOWING OVER RTE 6
&&
EVENT NUMBER CTP1801953
PAHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1215 PM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1121 AM HEAVY RAIN HEBRON 41.84N 78.07W
07/04/2018 E3.00 INCH POTTER PA 911 CALL CENTER
OSWAYO CREEK FLOWING OVER RTE 44
&&
EVENT NUMBER CTP1801954
PAHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1220 PM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1119 AM HEAVY RAIN 1 E OSWAYO 41.92N 78.00W
07/04/2018 E2.50 INCH POTTER PA 911 CALL CENTER
OSWAYO CREEK FLOWING OVER RTE 244
&&
EVENT NUMBER CTP1801955
PAHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1224 PM EDT WED JUL 04 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1200 PM HEAVY RAIN GALETON 41.74N 77.65W
07/04/2018 M4.73 INCH POTTER PA CO-OP OBSERVER
HEAVIEST 3 HOUR RAINFALL IN 50 YEARS OF OBSERVING
&&
EVENT NUMBER CTP1801956
PAHThe State College radar (KCCX), 115 km away, was scanning. The volume nearest the first event began at 16:29 UTC.
5 thunderstorm wind, 1 flash flood, 1 heavy rain. Local standard time, as filed.
Flash flooding reported across the county with Pushersiding Road closed near Ulysses, Peet Brook Road flooded near Andrews Settlement, Route 6 flooded west of Galeton, and Oswayo Creek flowing over Route 44 near Hebron. West Pike reported 6.10 inches and 4.73 inches in Galeton.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires across Hecla Road near Mingoville.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires onto SR 1025 near the communications tower.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees and wires onto Briar Creek Road.
Delete.
A severe thunderstorm producing winds estimated near 60 mph knocked down multiple trees and produced quarter-sized hail near Confluence.
A severe thunderstorm producing winds estimated near 60 mph knocked down trees near the intersection of Orrstown Road near Sandy Mountain Road.
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, July 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: 764811, 762871, 762873, 762874, 776983, 762875, 762876.