Unseasonably cold west-northwest flow over Lake Erie produced 2 to 5 inches of lake-effect snow across portions of the Northwest Mountains in Central Pennsylvania with higher amounts observed over the Snowbelt region of northwest Warren County. In addition, an intense snow band developed over portions of the Central Mountains producing a narrow swath of 2 to as much as 8 inches of snow in a 4-5…
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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.
Unseasonably cold west-northwest flow over Lake Erie produced 2 to 5 inches of lake-effect snow across portions of the Northwest Mountains in Central Pennsylvania with higher amounts observed over the Snowbelt region of northwest Warren County. In addition, an intense snow band developed over portions of the Central Mountains producing a narrow swath of 2 to as much as 8 inches of snow in a 4-5 hour period from around midnight on the 8th through 5am.
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 7, 3:25 AM EST, 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 425 AM EDT SAT APR 7 2007 .SYNOPSIS... A PERSISTENT NORTHWEST FLOW ALOFT WILL CONTINUE TO BRING THE REGION MUCH BELOW NORMAL TEMPS THROUGH EARLY IN THE COMING WEEK...ALONG WITH PLENTY OF CLOUDS AND MAINLY MOUNTAIN SNOW SHOWERS. A SLOW WARM UP IS EXPECTED INTO THE MIDDLE OF THE UPCOMING WEEK...WITH TEMPERATURES PEAKING NEAR NORMAL ON WEDNESDAY. ANOTHER STORM SYSTEM WILL DEVELOP TO OUR SOUTHWEST AND BRING RAIN OR POSSIBLY A WINTRY MIX OF PRECIPITATION WEDNESDAY AFTERNOON INTO THURSDAY FOLLOWED BY A BRIEF COOL DOWN. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MID LEVEL COLD ADVECTION WILL OCCUR THIS MORNING WITH THE MEAN 850-700 HPA THERMAL TROUGH SETTING UP SHOP ACROSS THE REGION THIS AFTERNOON AND TONIGHT. SUBSIDENCE INVERSION BASE LIFTS TO ABOVE 10 KFT AGL THIS AFTERNOON. THIS FACTOR...COMBINED WITH DEEP LLVL MOISTURE VIA A FETCH OFF THE GLAKES AND THE STRONG APRIL SUN WILL PROMOTE INCREASING SNOW SHOWERS AND LOCALLY HEAVY SQUALLS ACROSS THE CENTRAL AND NW LATE THIS MORNING AND THIS AFTERNOON. WEAK LLVL RIDGING TO THE NW OF A DEVELOPING LOW OFF THE MID ATLANTIC COAST WILL LEAD TO MORE SCATTERED SHSN THERE...BUT A POCKET OF STEEP 850-500 HPA LAPSE RATES AND TOTAL TOTALS IN THE U40S WILL BRING A FEW SQUALLS EVEN ALONG THE I-81 CORRIDOR FROM LATE THIS MORNING THROUGH THE AFTERNOON. UPGRADED THE LES ADVISORY TO A WARNING FOR WARREN COUNTY AND EXTENDED IT /ALONG WITH THE LES ADVISORY FOR MCKEAN COUNTY/ UNTIL 04Z SUNDAY. BUFKIT NAM SOUNDINGS INDICATE A PERFECT MARRIAGE OF THE OMEGA FIELD WITH THE FAVORABLE DENDRITIC SNOW GROWTH THERMAL RIBBON TODAY THROUGH EARLY TONIGHT. 925-850 HPA MEAN WIND STAY JUST SHY OF 270 DEG FOR MUCH OF TODAY BEFORE VEERING TO BETWEEN 280 AND 285 DEG LATE THIS AFTERNOON AND THIS EVENING...WHICH MAY LEAD TO THE HEAVIEST LES BANDS FOCUSED ACROSS WARREN AND PARTS OF MCKEAN COUNTIES BETWEEN 22Z AND 04Z. MAX TEMPS TODAY WILL BE AN UNREASONABLE 20F OR SO BELOW THEIR NORMAL HIGHS IN THE 40S NORTHWEST...TO THE LOWER AND MID 50S ELSEWHERE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... FAIRLY WELL ALIGNED...COLD NW LOW/MID LEVEL FLOW WILL CONTINUE TO PRODUCE SNOW SHOWERS AND SCATTERED SQUALLS TONIGHT INTO SUNDAY...THOUGH MORE OF A NORTHWESTERLY FETCH MAY LEAD TO MORE NARROW AND LESS INTENSE SNOW BANDS. STILL...THE POTENTIAL EXISTS FOR UP TO SEVERAL MORE INCHES OF SNOW ACROSS THE NW MTNS...AND PERHAPS A FEW SPOTS ACROSS THE LAUREL HIGHLANDS WEST OF ROUTE 219... WITH ANOTHER COATING TO 2 INCHES POSSIBLE OVER THE REMAINDER OF THE WESTERN AND NRN MTNS. THE NW WIND WILL GUST BETWEEN 25 AND 30 MPH ONCE AGAIN THIS AFTERNOON AND SUNDAY AFTERNOON. MAX TEMPS /COMPARED TO SAT AFTERNOON/ ONLY WARM BY 2-5 DEG SUNDAY DUE MAINLY TO A BIT MORE IN THE WAY OF EXPECTED SUNSHINE...AN A SLIGHT INCREASE IN TEMPS ALOFT. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... UPPER HEIGHTS BUILD SLOWLY MONDAY AND TUESDAY AS A NEARLY N/S RIDGE OF SFC HIGH PRESSURE BUILDS ACROSS THE REGION. INCREASING SUNSHINE WILL ALLOW DAYTIME TEMPS TO APPROACH NORMAL BY WEDNESDAY. OPERATIONAL MODELS AND MEDIUM RANGE ENSEMBLES CONTINUE TO HIGHLIGHT THE POTENTIAL FOR A SIGNIFICANT COLD RAIN...POSSIBLY CHANGING TO A HEAVY WET SNOW EVENT IN SOME LOCATIONS OF NRN PENN WEDNESDAY AFTERNOON INTO THURSDAY. LOW PRESSURE A STRONG SHORT WAVE WILL TRACK EAST ACROSS THE OHIO VALLEY WITH SECONDARY LOW PRESSURE DEVELOPMENT LIKELY ALONG THE MID ATLANTIC COAST BENEATH THE EXPECTED COUPLED JET TRANSVERSE CIRCULATION. A SOLID 4 TO 8 TENTHS OF AN INCH OF QPF IS ANTICIPATED WITH THE MIDWEEK STORM...WITH A LOW PROBABILITY OF OVER AN INCH ACROSS PARTS OF CENTRAL AND ERN PENN. ANOMALOUS...ALBEIT SERLY...850 HPA FLOW FOR AN APPROX 12 HOUR PERIOD WILL SUPPORT THE POTENTIAL OF LOCALLY HEAVY PRECIP. BELOW NORMAL 850 HPA TEMPS SPREAD ACROSS THE REGION AGAIN LATE NEXT WEEK BUT THE COLD OUTBREAK WILL BE TEMPERED COMPARED TO THE CURRENT ONE. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... MOST SITES VFR AT THIS TIME...BUT THIS SHOULD NOT LAST LONG ACROSS THE WRN MTNS AS CELLULAR LAKE EFFECT SNOW SHOWERS AND LOWER CIGS BEGIN TO INVADE FROM NWRN PA PER THE LATEST 88D IMAGERY. LLVL STRATO CU WITH BASES HOVERING BTWN 3-5KFT WILL BE THE RULE ACROSS THE WRN/CENTRAL AIRFIELDS WITH LOWER /MVFR CIGS AND IFR VIS/ PSBL IN -SHSN ACTIVITY...WHICH WILL SOON IMPACT KBFD AND GET INTO KJST AROUND 09Z. A MID LVL CLOUD DECK AROUND 10KFT MORE COMMON FURTHER EAST ASSOC WITH S/W ENERGY EMBEDDED WITHIN THE MEAN CYCLONIC FLOW...PRODUCING AREAS OF -SN ACROSS SRN MD/NRN VA. THIS UPPER LEVEL DISTURBANCE WILL EVENTUALLY INDUCE A SFC LOW INVOF TIDEWATER REGION OF VA PER LATEST 3/6HRLY PRES FALLS AND TRACK NEWD OUT TO SEA WHILE ACTING TO DEEPEN/SHARPEN THE MID/UPPER LVL TROF OVER THE NORTHEAST. WHILE SOME MID LVL RETURNS ARE DEPICTED ON THE 88-D MOSAIC OVER FAR SERN PA...DONT THINK THE -SN WILL MAKE IT THAT FAR NORTH AND HAVE JUST LOWERED CIGS AT KMDT TO AROUND 4KFT BY 10Z. THE CORE OF THE COLDEST AIR ALOFT WILL MOVE OVERHEAD THIS AFTN ALONG WITH RATHER STEEP LAPSE RATES RESULTING IN SUBSTANTIAL LOW- MID LVL INSTABILITY. THIS WILL LEAD TO POCKETS OF MODERATE TO HEAVY -SHSN IN LCL IFR CONDS. GIVEN THAT INVERSION HEIGHTS CLIMB TO AOA 10KFT ACROSS MUCH OF THE WRN/CENT TERMINALS...WOULD NOT BE SURPRISED TO SEE LIFR VIS IN CONVECTIVE -SHSN...ESP AT KBFD AND KJST. A MEAN BLYR WIND AROUND 270 DEGS WILL AID IN OROGRAPHIC ENHANCEMENT ACROSS THE WRN TERMINALS...WHILE LIMITING -SHSN ACROSS THE LWR SUSQ VLY COURTESY OF DOWNSLOPE LLVL FLOW. STRONG MIXING WILL SUPPORT SFC WNDS GUSTS OF 20-30KTS...WHICH MAY CAUSE LLVL MECHANICAL TURBULENCE DURING TAKEOFF AND APPROACH AT TIMES. PDS OF -SHSN CONTINUE INTO SUNDAY AS THE ERN TROF GRADUALLY LIFTS NEWD...GIVING WAY TO IMPROVING CONDS BY EARLY NEXT WEEK. SFC HI PRES BUILDS IN ON TUES. HOWEVER...ANOTHER SYSTEM BEGINS TO TAKE AIM ON THE MID-ATLANTIC REGION BY EARLY WED WITH FLYING CONDS TRENDING DOWNWARD BY THAT TIME. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR PAZ005. LAKE EFFECT SNOW WARNING UNTIL MIDNIGHT EDT TONIGHT FOR PAZ004. && SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/RXR AVIATION...STEINBUGL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 229 PM EDT FRI APR 6 2007 PAZ006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-071830- POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE- SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET- BEDFORD-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING-SULLIVAN- SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND- ADAMS-YORK-LANCASTER- 229 PM EDT FRI APR 6 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY A STORM SYSTEM WILL MOVE TOWARD PENNSYLVANIA AND ARRIVE DURING THE MIDDLE OF THE UPCOMING WEEK. THIS STORM HAS THE POTENTIAL TO PRODUCE EITHER RAIN OR SNOW OVER THE REGION DEPENDING ON THE ACTUAL TRACK. THE AREAS THAT ARE MORE LIKELY TO SEE SNOWFALL WOULD BE THE HIGHER ELEVATIONS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ004-005-071830- WARREN-MCKEAN- 229 PM EDT FRI APR 6 2007 ...LAKE EFFECT SNOW ADVISORY IN EFFECT FROM 8 PM THIS EVENING TO 11 AM EDT SATURDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...THIS AFTERNOON AND TONIGHT PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. LAKE EFFECT SNOW ADVISORY .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. LAKE EFFECT SNOW ADVISORY ALSO...A STORM SYSTEM WILL MOVE TOWARD PENNSYLVANIA AND ARRIVE DURING THE MIDDLE OF THE UPCOMING WEEK. THIS STORM HAS THE POTENTIAL TO PRODUCE EITHER RAIN OR SNOW OVER THE REGION DEPENDING ON THE ACTUAL TRACK. THE AREAS THAT ARE MORE LIKELY TO SEE SNOWFALL WOULD BE THE HIGHER ELEVATIONS. .SPOTTER INFORMATION STATEMENT... SPOTTERS...PLEASE REPORT SNOWFALL. DANGELO
SPECIAL WEATHER STATEMENT...UPDATED NATIONAL WEATHER SERVICE STATE COLLEGE PA 1215 AM EDT SAT APR 7 2007 PAZ017>019-080445- CLEARFIELD-NORTHERN CENTRE-SOUTHERN CENTRE- 1215 AM EDT SAT APR 7 2007 ...INTENSE SNOW SQUALLS AFFECTING PORTIONS OF CLEARFIELD AND CENTRE COUNTIES... AT 1213 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE AN INTENSE...PERSISTENT SNOW BAND LOCATED ALONG OR JUST SOUTH OF A LINE EXTENDING FROM CURWENSVILLE...PHILLIPSBURG TO STATE COLLEGE AND POTTERS MILLS. LOCALLY HEAVY SNOW SQUALLS EMBEDDED WITH THE INTENSE SNOW BAND WILL REMAIN NEARLY STATIONARY THROUGH 1245 AM. THE SNOW WILL RAPIDLY DROP VISIBILITIES IN THE SQUALL TO LESS THAN A HALF OF A MILE. IN ADDITION...A QUICK ONE TO THREE INCHES OF SNOW MAY QUICKLY ACCUMULATE ON UNTREATED ROADS...BRIDGES AND OVERPASSES. THE SNOW WILL FALL ONTO WARM ROAD SURFACES...WHICH WILL CAUSE IT TO QUICKLY MELT AND THEN RE-FREEZE. THIS COULD CREATE VERY ICY CONDITIONS IF THE ROAD SURFACE IS UNTREATED. USE EXTREME CAUTION IF YOU MUST TRAVEL INTO OR THROUGH THIS POTENTIALLY DANGEROUS SNOW SQUALL. CONSIDER DELAYING TRAVEL UNTIL THE SQUALL PASSES YOUR LOCATION. FORECASTER:KF/STEINBUGL
The national radar mosaic for the moment the first event began.
1 lake-effect snow. Local standard time, as filed.
Periods of lake-effect snow showers accumulated to 2 to 4 inches across much of Warren county. Higher amounts were observed over the Snowbelt region with 6 inches of snow measured in Youngsville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2007Every state in 2007This day in weather historyWarnings in Pennsylvania, April 2007
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: 14492.