A weak surface front moved across the state of Pennsylvania on Saturday and generated showers and thunderstorms. As these storms moved east, they interacted with an unstable environment.
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 BGM wrote it up.
A weak surface front moved across the state of Pennsylvania on Saturday and generated showers and thunderstorms. As these storms moved east, they interacted with an unstable environment. Some of these storms became severe and caused damaging winds.
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 Binghamton, NY wrote its last area forecast discussion before the first event at Aug 19, 2:02 PM EST, 4 hours 3 minutes earlier.
Area Forecast Discussion National Weather Service Binghamton NY 302 PM EDT Sat Aug 19 2017 .SYNOPSIS... An upper level disturbance will move across NY and PA this afternoon and evening bringing scattered showers and isolated thunderstorms to our area. After this disturbance passes by, high pressure will build into our region for Sunday and Monday with fair weather and seasonable temperatures. The next chance for precipitation will come Tuesday as a cold front approaches the region. && .NEAR TERM /THROUGH SUNDAY/... Scattered showers are developing across western NY and northwest Pennsylvania as weak capping indicated on the 12z Buffalo sounding begins to break down. Strongest storms are beginning to develop over eastern Ohio and these will track east-southeast across western Pa during the next few hours remaining well to our south and west. Latest HRRR and RAP forecasts continue to indicate only marginal levels of instability in our area with MLCAPE values maxing out near or just above 500 J/kg and the best chances for organized convection remaining to our south and west. We are expecting scattered showers with isolated thunder to move across our area during the mid afternoon through early evening followed by clearing overnight, then patchy low clouds and fog around daybreak Sunday. Sunday looks like a mostly sunny and seasonably warm day with highs in the mid 70s to lower 80s as high pressure builds across the area. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... 300 PM EDT Update... Minor changes were made to the previous forecast. Zonal flows will prevail over the region from Sunday night through Tuesday morning, combined with ridging at mid-lvls and surface high pressure. This combination will result in mostly sunny skies, above normal temperatures with no chance for precip. Temps Monday night will range in the mid 50s/low 60s. Temps Tues afternoon will rise into the mid/upper 80s and fall into the 60s Tues night. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... 300 PM EDT Update... Updated with new WPC guidance... Surface high pressure will slide off to the east early Tuesday morning as the next storm system approaches the region from the west. There continues to be fairly decent model agreement on the timing of the next system with showers moving into western NY as a sfc low moves NE into Quebec Tuesday night and a fropa moves across Ny/PA Tues night. Showers and thunderstorms are likely across the region late Tuesday evening into Tuesday night. This could be our next shot for a widespread rainfall event. The upper level shortwave that will force the sfc low/fropa across the region will be slow to move east, thus showers and and a possible rumble of thunder will be possible through Thursday. High pressure is expected to build back into the area Thurs evening. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... Scattered showers with isolated thunder will develop across the area this afternoon into this evening. A shower is possible at any of the TAF sites between 19z and 01z today and have included a tempo group at BGM/ELM/AVP for a showers where we believe the best chance for a shower will be. After 01z skies will become clear to partly cloudy with patches of low cloud and fog after 06z. Skies will become mostly sunny on Sunday with just scattered cu. Winds will be west at 10 to 15 kts with a few higher gusts this afternoon, northwest at less than 10 kts tonight and west at around 10 kts on Sunday. Outlook... Sunday through Monday...VFR. Possible IFR in valley fog early. Tuesday...Restrictions possible in thunderstorms. Wednesday...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && SYNOPSIS...DJN NEAR TERM...DJN/MSE SHORT TERM...KAH LONG TERM...KAH AVIATION...DJN/MSE
Hazardous Weather Outlook National Weather Service Binghamton NY 223 PM EDT Sat Aug 19 2017 NYZ009-015>018-022>025-036-037-044>046-055>057-062-PAZ038>040-043- 044-047-048-072-201830- Northern Oneida-Yates-Seneca-Southern Cayuga-Onondaga-Steuben- Schuyler-Chemung-Tompkins-Madison-Southern Oneida-Cortland-Chenango- Otsego-Tioga-Broome-Delaware-Sullivan-Bradford-Susquehanna- Northern Wayne-Wyoming-Lackawanna-Luzerne-Pike-Southern Wayne- 223 PM EDT Sat Aug 19 2017 This Hazardous Weather Outlook is for central New York and northeast Pennsylvania. .DAY ONE...This Afternoon and Tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Sunday through Friday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. MSE
Special Weather Statement
National Weather Service Binghamton NY
534 PM EDT SAT AUG 19 2017
NYZ055-056-192215-
Tioga NY-Broome NY-
534 PM EDT SAT AUG 19 2017
...STRONG THUNDERSTORM WILL AFFECT...SOUTHWESTERN BROOME AND TIOGA
COUNTIES UNTIL 615 PM EDT...
At 534 PM EDT, Doppler radar was tracking a strong thunderstorm near
Lockwood, or 8 miles north of Waverly, moving east at 25 mph.
Half inch hail and winds in excess of 40 mph will be possible with
this storm.
Locations impacted include...
Vestal, Johnson City, Endicott, Barton, Maine, Waverly, Owego, Newark
Valley, Candor and Spencer.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Heavy rainfall is also occurring with this storm, and may lead to
minor 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.
&&
LAT...LON 4215 7655 4216 7653 4222 7654 4224 7653
4227 7591 4201 7603 4203 7655 4205 7654
4207 7655 4213 7656
TIME...MOT...LOC 2134Z 278DEG 22KT 4213 7650
BJTSpecial Weather Statement National Weather Service Binghamton NY 540 PM EDT SAT AUG 19 2017 NYZ044-045-055-056-192245- Chenango NY-Cortland NY-Tioga NY-Broome NY- 540 PM EDT SAT AUG 19 2017 ...A LINE OF STRONG THUNDERSTORMS WILL AFFECT...NORTHWESTERN BROOME...SOUTHEASTERN CORTLAND...NORTHEASTERN TIOGA AND CENTRAL CHENANGO COUNTIES UNTIL 645 PM EDT... At 540 PM EDT, Doppler radar was tracking strong thunderstorms along a line extending from near East Freetown to Berkshire. Movement was east at 30 mph. Half inch hail and winds in excess of 40 mph will be possible with these storms. Locations impacted include... Norwich, Guilford, Nanticoke, Coventry, Greene, Oxford, Berkshire, Cincinnatus, Preston and Willet. PRECAUTIONARY/PREPAREDNESS ACTIONS... Heavy rainfall is also occurring with these storms, and may lead to minor flooding. Do not drive your vehicle through flooded roadways. 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. && LAT...LON 4256 7538 4219 7559 4229 7625 4258 7595 TIME...MOT...LOC 2140Z 276DEG 26KT 4252 7594 4231 7618 BJT
Special Weather Statement National Weather Service Binghamton NY 615 PM EDT SAT AUG 19 2017 NYZ055-056-192300- Tioga NY-Broome NY- 615 PM EDT SAT AUG 19 2017 ...STRONG THUNDERSTORM WILL AFFECT...SOUTHWESTERN BROOME AND SOUTHEASTERN TIOGA COUNTIES UNTIL 700 PM EDT... At 615 PM EDT, Doppler radar was tracking a strong thunderstorm over West Corners, or over Endicott, moving east at 30 mph. Half inch hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Binghamton, Vestal, Johnson City, Endicott, Kirkwood, Conklin, Maine, Port Dickinson, Nws Binghamton and Apalachin. PRECAUTIONARY/PREPAREDNESS ACTIONS... Heavy rainfall is also occurring with this storm, and may lead to minor flooding. Do not drive your vehicle through flooded roadways. && LAT...LON 4202 7622 4221 7609 4220 7564 4200 7566 TIME...MOT...LOC 2215Z 274DEG 25KT 4211 7611 BJT
Special Weather Statement
National Weather Service Binghamton NY
631 PM EDT SAT AUG 19 2017
PAZ038-192315-
Bradford PA-
631 PM EDT SAT AUG 19 2017
...STRONG THUNDERSTORM WILL AFFECT...NORTHWESTERN BRADFORD COUNTY
UNTIL 715 PM EDT...
At 631 PM EDT, Doppler radar was tracking a strong thunderstorm near
Sylvania, or near Troy, moving east at 35 mph.
Half inch hail and winds in excess of 40 mph will be possible with
this storm.
Locations impacted include...
Sayre, Athens, Towanda, Ridgebury, Troy, Sheshequin, Ulster,
Litchfield, North Towanda and West Burlington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Heavy rainfall is also occurring with this storm, and may lead to
minor flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4199 7637 4169 7643 4173 7689 4174 7690
4196 7692
TIME...MOT...LOC 2231Z 272DEG 32KT 4186 7687
BJTSpecial Weather Statement
National Weather Service Binghamton NY
643 PM EDT SAT AUG 19 2017
NYZ046-057-192330-
Otsego NY-Delaware NY-
643 PM EDT SAT AUG 19 2017
...STRONG THUNDERSTORM WILL AFFECT...SOUTHERN OTSEGO AND NORTHWESTERN
DELAWARE COUNTIES UNTIL 730 PM EDT...
At 643 PM EDT, Doppler radar was tracking a strong thunderstorm over
Gilbertsville, or 11 miles west of Oneonta, moving east at 40 mph.
Half inch hail and winds in excess of 40 mph will be possible with
this storm.
Locations impacted include...
Oneonta, Davenport, Maryland, Westville, Kortright, New Lisbon,
Otego, Morris, Milford and Gilbertsville.
LAT...LON 4237 7534 4253 7538 4255 7537 4257 7533
4267 7486 4235 7473
TIME...MOT...LOC 2243Z 265DEG 34KT 4248 7529
BJTSpecial Weather Statement National Weather Service Binghamton NY 656 PM EDT SAT AUG 19 2017 NYZ045-056-057-200000- Chenango NY-Broome NY-Delaware NY- 656 PM EDT SAT AUG 19 2017 ...STRONG THUNDERSTORM WILL AFFECT...SOUTHEASTERN BROOME... SOUTHWESTERN DELAWARE AND SOUTH CENTRAL CHENANGO COUNTIES UNTIL 800 PM EDT... At 656 PM EDT, Doppler radar was tracking a strong thunderstorm over Windsor, or 12 miles east of Binghamton, moving east at 35 mph. Half inch hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Walton, Sanford, Colchester, Deposit, Hamden, Windsor, Afton, Harvard, Harpursville and Nineveh. PRECAUTIONARY/PREPAREDNESS ACTIONS... Heavy rainfall is also occurring with this storm, and may lead to minor flooding. Do not drive your vehicle through flooded roadways. && LAT...LON 4198 7502 4201 7575 4223 7568 4224 7497 TIME...MOT...LOC 2256Z 272DEG 29KT 4210 7567 BJT
The Binghamton radar (KBGM), 80 km away, was scanning. The volume nearest the first event began at 23:04 UTC.
2 thunderstorm wind. Local standard time, as filed.
A thunderstorm moved across the region and became severe. This thunderstorm produced severe winds and knocked over multiple trees near the town of Troy and Ridgebury township.
A thunderstorm moved across the region and became severe. This thunderstorm produced severe winds and knocked over multiple trees in Harford and Ararat, PA.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2017Every state in 2017This day in weather historyWarnings in Pennsylvania, August 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: 712296, 712297.