2,274 first-hand accounts of flood events in Pennsylvania, ranked by impact. Each is a NOAA-written narrative of the moment.
A stationary frontal system over northeastern Pennsylvania combined with a weak upper level disturbance to focus heavy rain producing thunderstorms over the area.
Read the full account →A weak frontal system moving through a warm and excessively moist environment triggered thunderstorms with torrential rainfall. These storms were slow moving and produced copious amounts of rain which led to localized flash flooding of roads, small streams and a few residences…
Read the full account →A warm front lifted north into Pennsylvania during the day and became stalled during the early evening across the northeastern part of the Commonwealth.
Read the full account →A warm, moist airmass remained in place through the latter half of the month which allowed for daily shower and thunderstorm chances. Training storms was the primary factor to the resultant flash flooding as cells developed upshear of the initial updrafts in West Virginia, Ohio,…
Read the full account →Deep moisture combined with an approaching cold front and a favorable position of the jet stream triggered numerous heavy rain producing thunderstorms over northeastern Pennsylvania.
Read the full account →A line of thunderstorms developed east of Cleveland from a breeze off of Lake Erie near 17Z. Areas south and east of the line gave way to more storms as outflow boundaries converged. With high PWAT values (near 1.90) flash flooding became an issue with training storms.
Read the full account →A few weak disturbances tracked along the northern periphery of a strong upper ridge, triggering scattered thunderstorms. Many of the storms developed near a frontal boundary that was approaching the New York-Pennsylvania border.
Read the full account →A weak frontal system moving through a warm and excessively moist environment triggered thunderstorms with torrential rainfall. These storms were slow moving and produced copious amounts of rain which led to localized flash flooding of roads, small streams and a few residences…
Read the full account →A series of thunderstorms with torrential downpours caused flash flooding of most of the streams in the southeast part of Berks County. Flooding streams included the Conestoga, Monocacy and Manatawny.
Read the full account →A weak trough and remnant outflows initiated afternoon thunderstorms. Initial single cell development across eastern Ohio ultimately congealed along propagating cold pools and surged southeast.
Read the full account →A weak disturbance in the upper atmosphere slowly moved across the northern tier of Pennsylvania during the afternoon. This feature, along with a stationary frontal boundary at the surface over Northeast Pennsylvania triggered scattered to numerous thunderstorms during the heat…
Read the full account →The remnant low pressure center of Hurricane Ida passed across West Virginia and the Central Appalachian Mountains from late August 31st through September 1st.
Read the full account →A deep plume of tropical moisture had spread over Northeast Pennsylvania ahead of the remnants of Tropical Storm Debby. Prolonged torrential rains blanketed the region during the night and early morning hours before becoming enhanced by the approaching tropical remnants.
Read the full account →Several rounds of thunderstorms trained over portions of Lawrence, Allegheny, Westmoreland Clarion and Beaver counties on June 6th. This was a result of a very moist airmass and a stationary boundary located over northern Ohio and northwestern Pennsylvania.
Read the full account →Several rounds of thunderstorms trained over portions of Lawrence, Allegheny, Westmoreland Clarion and Beaver counties on June 6th. This was a result of a very moist airmass and a stationary boundary located over northern Ohio and northwestern Pennsylvania.
Read the full account →Deep moisture combined with an approaching cold front and a favorable position of the jet stream triggered numerous heavy rain producing thunderstorms over northeastern Pennsylvania.
Read the full account →A weak area of low pressure moved into Northeastern Pennsylvania during the afternoon which provided a focus for heavy rain-producing thunderstorms.
Read the full account →A weak area of low pressure moved into Northeastern Pennsylvania during the afternoon which provided a focus for heavy rain-producing thunderstorms.
Read the full account →Slow moving pulse storms created flash flooding conditions across the region. The storms developed in a very moist, buoyant environment where 2000-3000 J/kg SBCAPE and 1.7-1.9 inch PW values, supported very efficient rainfall rates.
Read the full account →The combination of a deep, slow moving upper-level trough across the West Coast and a cold high pressure over the Midwest created the perfect setup for a Winter Storm/Ice Storm/flooding scenario in portions of the Ohio River Valley.
Read the full account →A passing upper level trough with strong mid-level flow and diurnal heating under a moist low-level airmass helped generate severe storms across the Ohio River Valley. Effective bulk shear was 30-40kts and supported storm organization.
Read the full account →A strong low pressure system moved through the Ohio Valley on Monday, April 13 and extended a cold front across northwestern Pennsylvania on the afternoon of the 13th.
Read the full account →A warm front lifted north into Pennsylvania during the day and became stalled during the early evening across the northeastern part of the Commonwealth.
Read the full account →The risk for severe storms continued May 29th as necessary ingredients stayed in place. An unstable/ buoyant atmosphere, wind shear to sustain updrafts, and large scale |ascension with a crossing shortwave were all present.
Read the full account →