Heavy rain caused localized flooding in York County.
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.
Heavy rain caused localized flooding in York County.
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 Apr 20, 2:01 PM EST, 3 hours 59 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 301 PM EDT SUN APR 20 2008 .SYNOPSIS... A MOIST SOUTHEASTERLY FLOW OF AIR WILL PREVAIL OVER CENTRAL PENNSYLVANIA OVER THE NEXT FEW DAYS AS UPPER LOW PRESSURE DRIFTS SLOWLY SOUTHEAST ACROSS THE CENTRAL APPALACHIANS. WIDESPREAD SHOWERS AND EMBEDDED NARROW BANDS OF THUNDERSTORMS...MAINLY ACROSS SOUTHERN PENNSYLVANIA TONIGHT...WILL DIMINISH DURING THE DAY MONDAY WITH JUST LINGERING SHOWERS OR PATCHY DRIZZLE INTO MONDAY NIGHT. MANY LOCATIONS ACROSS SOUTH CENTRAL PENNSYLVANIA AND THE LAUREL HIGHLANDS WILL SEE ONE TO TWO INCHES OF RAINFALL OVER THE NEXT 36 HOURS...WITH LOCALLY HEAVIER AMOUNTS POSSIBLE. CONDITIONS WILL IMPROVE WITH TEMPERATURES MODERATING DURING THE PERIOD TUESDAY THROUGH FRIDAY AS A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT BUILDS OVER THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 12KM NAM...925-850 HPA THETA-E CONVERGENCE AND LOW LEVEL BASED INSTABILITY FIELDS HAVE WORKED LIKE A CHARM SO FAR TODAY...AND NAILED THE LOCATION...BANDED STRUCTURE...AND SLOW EASTWARD DRIFT TO THE LEADING EDGE OF THE TRAINING HEAVY SHOWERS AND EMBEDDED TSRA ACROSS SCENT PENN AND THE LOWER AND WEST BRANCH SUSQ VALLEY. LOCALIZED RAINFALL REPORTS AND MPE VALUES IN EXCESS OF ONE INCH WERE NOTED...WITH PEA TO DIME SIZE HAIL CONTAMINATION LEADING TO HIGH END VALUES AROUND 2 INCHES ALONG THE YORK CTY BORDER WITH MARYLAND. THE EASTERN EDGE OF THE SHOWERS/TSRA SHOULD COME TO A HALT LATE TODAY...THEN GRADUALLY DRIFT BACK TO THE SOUTHWEST OVERNIGHT WITH RAINFALL RATES GRADUALLY DIMINISHING FROM LATE EVENING ON. STILL...THE LONG DURATION AMOUNTS OF LOCALLY 2 TO 3 INCHES (NEARING THE 12+ HOUR HEADWATER GUIDANCE FOR MINOR FLOODING TO BEGIN) WILL LEAD TO THE POTENTIAL OF SOME SMALL STREAM AND POOR DRAINAGE FLOODING ACROSS SCENT PENN...AND WILL CONTINUE THE CURRENT FLOOD WATCH THROUGH MONDAY. SREF SFC BASED CAPE OF UP TO 500 J/KG ACROSS OUR SE ZONES AT 21Z...DIPS BACK TO JUST 100-200 J/KG BETWEEN 00Z AND 03Z MONDAY...AND BECOMES CONFINED TO A FAIRLY NARROW NNW/SSE BAND FROM NEAR KHGR TO KUNV. THIS WILL CONTINUE TO SUPPORT PERIODS OF HEAVY SHRA AND TSRA THROUGH EARLY TONIGHT. && .SHORT TERM /MONDAY/... CURRENT PROJECTIONS OF THE VERY SLOW EASTWARD MOVEMENT OF THE UPPER LOW IS ON TRACK TO REACH THE NORTH CAROLINA/VA BORDER BY EARLY MONDAY MORNING. THE PERSISTENT...ANOMALOUS (-2 TO -3 STANDARD DEVIATION) 925 TO 850 SERLY FLOW WILL CONTINUE TO BRING WIDESPREAD LOW CLOUDS AND MUCH COOLER MAX TEMPS THAN RECENT DAYS (OR IN THE L60S ACROSS THE CENTRAL AND SOUTH...WITH UPPER 60S ACROSS THE NW MTNS WHERE BREAKS OF SUNSHINE WILL DEVELOP). SHOWERS WILL BE MOST NUMEROUS NEAR...AND TO THE SOUTH OF THE PA TURNPIKE MONDAY WITH AREAS OF DRIZZLE POSSIBLE ACROSS THE HIGHER TERRAIN OF CENTRAL AND SRN PENN IN THE MOIST UPSLOPE FLOW. LITTLE OR NO RAIN WILL FALL ACROSS THE REGION NORTH OF INTERSTATE 80. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... UPPER LVL VORT FINALLY SLIDES FAR ENOUGH SE PULLING MOST OF THE MOISTURE WITH IT. EXPECT SECOND HALF OF TUE TO BE SOMEWHAT DRY WITH THE EXCEPTION OF MASON-DIXON LINE...BASED ON ENSEMBLED DATA. MID-LVL RIDGE TRIES TO LINGER ON BACKSIDE OF UPPER LVL VORT TUE NGT INTO WED...WHICH MAY ALLOW FOR A PERIOD OF DRY WX THRU WED MORNING. UPPER LVL POLAR VORT TRIES TO SLIDE INTO ALBERTA TUE NGT...AND WILL SWING A VORT LOBE SE INTO THE GRT LKS WED. WEAK THERMAL RIDGE POKES INTO MID-ATLANTIC WED AFTN PRIOR TO APPROACH OF FRONTAL BNDRY SWEEPING IN FROM THE WEST...WITH TEMPS NEARING 70 DEGREES IN NUMEROUS LOCATIONS. GRT LKS VORT WILL SLIDE NE INTO CENTRAL ONTARIO WED AFTN...WITH A FRONTAL BNDRY EXTENDING SE THRU OHIO RIVER VALLEY INTO EASTERN KY. MOISTURE WILL BE MARGINAL WITH MID-WEEK SYSTEM...HOWEVER EXPECT LAPSE RATES TO STEEPEN ENOUGH WED AFTN AHEAD OF BNDRY THAT WE MAY SEE SHOWERS AND ISO THUNDERSTORM. THE WILD CARD WILL BE IF VORT PASSES TOO FAR NORTH...MOISTURE WILL FOLLOW SUIT. RESULTING IN A WASHED OUT BNDRY AND A WEAK WIND SHIFT. YET ANOTHER SFC RIDGE PROMPTLY SLIDES IN FOR THUR/FRI AND WILL QUICKLY DRY OUT BNDRY LYR. 850MB TEMPS FALL BACK INTO THE +6 TO +10 BOTH DAYS...SO AFTN TEMPS WILL BE AROUND 70. IF WED ENDS UP BEING DRY THEN WE MIGHT BUMP THOSE TEMPS UP A TAD GIVEN DECREASED HEAT CAPACITY FROM A DRY BNDRY LYR. ENSEMBLES PROG YET ANOTHER SHORTWAVE TO MOVE INTO THE MID-WEST AND BECOME WRAPPED UP. THIS WILL MOST LIKELY SWING A SECONDARY VORT EAST LATE FRI/SAT TOWARDS THE MID-ATLANTIC. SO HAVE CHC SHOWERS FOR THE UPCOMING WEEKEND. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... WIDESPREAD MVFR CIGS AND VSBYS COVERING THE SUSQ VALLEY AND POINT WEST LATE TODAY WILL DETERIORATE TO MAINLY IFR CIGS WITH MVFR TO IFR VSBYS OVERNIGHT THROUGH 14Z MONDAY...CONDITIONS WILL SLOWLY IMPROVE FROM NORTH TO SOUTH MONDAY AFTERNOON AND NIGHT. 10 KT EAST/SE WINDS WILL BE TOPPED BY AT LEAST SEVERAL HOURS OF 30-35 KT SE WINDS AT 1.3 TO 2KFT AGL TONIGHT...LEADING TO MARGINAL LOW LEVEL WIND SHEAR AT ALL TAF SITES. MAINLY VFR FLYING CONDITIONS WILL OCCUR BY MONDAY AFTERNOON ACROSS NORTHERN PENN AND BY MIDNIGHT ACROSS CENTRAL PENN. LOW CLOUDS (MVFR TO IFR CIGS) AND MVFR VSBYS MAY LINGER INTO TUESDAY MORNING ACROSS SOUTHERN PENN...TAF SITES KJST...KAOO AND KMDT. HIGH PRESSURE WILL BUILD SOUTH ACROSS THE REGION FOR THE TUESDAY AFTERNOON THROUGH FRIDAY PERIOD...PROVIDING MAINLY VFR CONDITIONS. JUST A SEVERAL HOUR PERIOD OF MVFR CIGS AND VSBYS ARE POSSIBLE DURING THE AFTERNOON HOURS WEDNESDAY AS A WEAK COLD FRONT MOVES SE ACROSS PENN. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH MONDAY EVENING FOR PAZ024>028-033>036-056- 063>065. && SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...BEACHLER AVIATION...LAMBERT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 944 AM EDT SUN APR 20 2008 PAZ004>006-010>012-017>019-037-041-042-045-046-049>053-057>059-066- 211345- WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD- NORTHERN CENTRE-SOUTHERN CENTRE-TIOGA-NORTHERN LYCOMING-SULLIVAN- SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-DAUPHIN-SCHUYLKILL-LEBANON-LANCASTER- 944 AM EDT SUN APR 20 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ024>028-033>036-056-063>065-211345- CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-BEDFORD-FULTON- FRANKLIN-PERRY-CUMBERLAND-ADAMS-YORK- 944 AM EDT SUN APR 20 2008 ...FLOOD WATCH IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH MONDAY 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. FLOOD WATCH. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. PERSISTENT BANDS OF MODERATE TO HEAVY RAIN WITH EMBEDDED THUNDERSTORMS WILL GRADUALLY DIMINISH DURING THE DAY MONDAY. STORM TOTAL RAINFALL OF 1 TO 2 INCHES WILL OCCUR ACROSS MUCH OF THE REGION...WITH UP TO 3 OR 4 INCHES POSSIBLE. .SPOTTER INFORMATION STATEMENT... SPOTTERS...PLEASE RELAY REPORTS OF HEAVY RAINFALL...EXCEEDING ONE INCH...TO THE NATIONAL WEATHER SERVICE OFFICE IN STATE COLLEGE. LAMBERT
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE STATE COLLEGE PA 144 PM EDT SUN APR 20 2008 PAZ065-201830- YORK- 144 PM EDT SUN APR 20 2008 ...A STRONG THUNDERSTORM WILL AFFECT EASTERN YORK COUNTY THROUGH 230 PM EDT... AT 136 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 12 MILES SOUTHEAST OF RED LION...MOVING TO THE NORTH NORTHWEST AT 22 MPH. WIND GUSTS TO 30 MPH AND HAIL BETWEEN PEA AND DIME SIZE ARE POSSIBLE WITH THIS STORM. EXPECT OCCASIONAL...DANGEROUS CLOUD TO GROUND LIGHTNING FROM THIS STORM. DO NOT SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. THIS STORM WILL BE NEAR FELTON...BROGUE AROUND 200 PM...HALLAM AND STONYBROOK AROUND 215 PM. FORECASTER: LAMBERT/EVANEGO
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE STATE COLLEGE PA 243 PM EDT SUN APR 20 2008 PAZ065-066-201930- LANCASTER-YORK- 243 PM EDT SUN APR 20 2008 ...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN LANCASTER COUNTY AND SOUTHEASTERN YORK COUNTY THROUGH 330 PM EDT... AT 240 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 11 MILES NORTH OF BEL AIR...MOVING NORTH NORTHWEST AT 22 MPH. WIND GUSTS TO 40 MPH AND HAIL BETWEEN PEA...AND DIME SIZE ARE POSSIBLE WITH THIS STORM. A 15 TO 30 MINUTE PERIOD OF VERY HEAVY RAIN WILL ALSO FALL FROM THIS STORM...AND WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SOME SMALL STREAMS. EXPECT FREQUENT...DANGEROUS CLOUD TO GROUND LIGHTNING FROM THIS STORM. DO NOT SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. THIS STORM WILL BE NEAR SUNNYBURN...HOLTWOOD AROUND 300 PM... BROGUE...SHENKS FERRY AROUND 315 PM AND WINDSOR AROUND 330 PM. FORECASTER: LAMBERT
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE STATE COLLEGE PA 402 PM EDT SUN APR 20 2008 PAZ036-063-064-202030- ADAMS-CUMBERLAND-FRANKLIN- 402 PM EDT SUN APR 20 2008 ...STRONG THUNDERSTORMS WILL AFFECT ADAMS...EASTERN FRANKLIN AND SOUTHWESTERN CUMBERLAND COUNTIES... AT 357 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STRONG THUNDERSTORMS FROM 9 MILES NORTHWEST OF WESTMINSTER TO 3 MILES NORTH OF THURMONT...MOVING NORTH AT 38 MPH. WIND GUSTS TO 40 MPH AND HAIL UP TO DIME SIZE ARE POSSIBLE WITH THESE STORMS. VERY HEAVY RAIN WILL WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. THESE STORMS WILL BE NEAR GERMANTOWN AROUND 410 PM...BONNEAUVILLE AROUND 415 PM...SEVEN STARS AROUND 420 PM...FAYETTEVILLE AROUND 425 PM AND BENDERSVILLE AROUND 430 PM. THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES... I-81 BETWEEN MILE MARKERS 20 AND 31. FORECASTER: LA CORTE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE STATE COLLEGE PA 435 PM EDT SUN APR 20 2008 PAZ026-036-056-063-064-202100- ADAMS-CUMBERLAND-FRANKLIN-HUNTINGDON-PERRY- 435 PM EDT SUN APR 20 2008 ...STRONG THUNDERSTORMS WILL AFFECT EAST CENTRAL HUNTINGDON... NORTHEASTERN FRANKLIN...NORTHERN ADAMS...SOUTHWESTERN PERRY AND WESTERN CUMBERLAND COUNTIES... AT 431 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STRONG THUNDERSTORMS FROM 9 MILES NORTHEAST OF GETTYSBURG TO 7 MILES SOUTH OF SHIPPENSBURG...MOVING NORTHWEST AT 40 MPH. WIND GUSTS TO 40 MPH AND HAIL UP TO DIME SIZE ARE POSSIBLE WITH THESE STORMS. VERY HEAVY RAIN WILL WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. THESE STORMS WILL BE NEAR SHIPPENSBURG AROUND 445 PM...MOUNT HOLLY SPRINGS AROUND 450 PM...NEWBURG AROUND 455 PM AND DOYLESBURG AROUND 500 PM. THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...THE PENNSYLVANIA TURNPIKE BETWEEN MILE MARKERS 193 AND 222...I-81 BETWEEN MILE MARKERS 17 AND 45. FORECASTER: LA CORTE
The national radar mosaic for the moment the first event began.
1 flood. Local standard time, as filed.
Heavy rain from a number of thunderstorms crossing the region during the afternoon and early evening caused flooding over Southwest York County. Several roads were flooded and closed. A mudslide was reported in Hanover, along with the development of a sinkhole.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2008Every state in 2008This day in weather historyWarnings in Pennsylvania, April 2008
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: 84641.