Alert archive / Pennsylvania / Flood Watches in 2008
Flood Watch 8, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flood watch at May 11, 2008, 3:37 AM EDT for Cecil County, Maryland; New Castle County, Delaware; Delaware County, Philadelphia County, Pennsylvania. It took effect at May 12, 2008, 12:00 AM EDT. It was in force for 10 hr.
The area
The counties it named.
The facts
- Issued
- May 11, 2008, 3:37 AM EDT (07:37 UTC)
- In effect from
- May 12, 2008, 12:00 AM EDT
- Expired
- May 12, 2008, 9:31 AM EDT
- In force
- 10 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Flood severity
- None
Counties New Castle County, DE, Cecil County, MD, Delaware County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 98 km from the middle of the area, began a volume at 07:36 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 7.6 hours before the alert went out and 185 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1556 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WGUS61 KPHI 110737 FFAPHI URGENT - IMMEDIATE BROADCAST REQUESTED FLOOD WATCH NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 337 AM EDT SUN MAY 11 2008 DEZ001-MDZ008-PAZ067-070-071-112100- /O.NEW.KPHI.FA.A.0008.080512T0600Z-080512T2200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NEW CASTLE-CECIL-CHESTER-DELAWARE-PHILADELPHIA- INCLUDING THE CITIES OF...WILMINGTON...ELKTON...WEST CHESTER... MEDIA 337 AM EDT SUN MAY 11 2008 ...FLOOD WATCH IN EFFECT FROM LATE TONIGHT THROUGH MONDAY AFTERNOON... THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A * FLOOD WATCH FOR PORTIONS OF NORTHERN DELAWARE...NORTHEAST MARYLAND AND SOUTHEAST PENNSYLVANIA...INCLUDING THE FOLLOWING AREAS...IN NORTHERN DELAWARE...NEW CASTLE. IN NORTHEAST MARYLAND...CECIL. IN SOUTHEAST PENNSYLVANIA...CHESTER... DELAWARE AND PHILADELPHIA. * FROM LATE TONIGHT THROUGH MONDAY AFTERNOON COMPLEX LOW PRESSURE WILL MOVE TOWARD THE AREA TODAY...ACROSS THE AREA TONIGHT AND OUT TO SEA SLOWLY ON MONDAY. THE SYSTEM WILL PULL A GOOD DEAL OF MOISTURE OFF THE ATLANTIC...AND CARRY WITH IT SOME INSTABILITY ABOVE THE SURFACE THAT COULD RESULT IN SOME THUNDERSTORMS. RAIN WILL BEGIN IN THE WATCH AREA LATE THIS AFTERNOON OR THIS EVENING. BEFORE THE BULK OF THE RAIN ENDS LATE MONDAY...ONE TO TWO INCHES OF RAIN IS FORECAST. IF ANY THUNDERSTORMS DO DEVELOP...MAINLY OVERNIGHT TONIGHT...THEN LOCALLY HIGHER RAINFALL AMOUNTS ARE POSSIBLE. BECAUSE OF THE RECENT RAINFALL OVER THE AREA...SOME OF THE MORE VULNERABLE STREAMS IN THE WATCH AREA WOULD BEGIN TO FLOOD IF IN EXCESS OF ONE AND ONE-HALF INCHES OF RAIN FELL. POOR DRAINAGE FLOODING ALSO IS POSSIBLE IF THUNDERSTORMS DEVELOP. A FLOOD WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR HEAVY RAIN ACROSS THE WATCH AREA...WHICH MAY LEAD TO FLOODING ALONG STREAMS AND CREEKS. IF YOU ARE IN THE WATCH AREA...CHECK YOUR PREPAREDNESS REQUIREMENTS. KEEP INFORMED...AND BE READY FOR ACTION IF FLOODING IS OBSERVED OR IF A FLOOD WARNING IS ISSUED. ONE WAY TO KEEP ABREAST OF EXISTING AND FORECASTED WATER CONDITIONS ON WATERWAYS THROUGHOUT THE REGION IS TO MONITOR THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ AVAILABLE ON OUR HOMEPAGE AT WWW.WEATHER.GOV/PHI. JUST CLICK THE AHPS ICON ON THE LEFT HAND MENU. $$ MPD
4 follow-up statements
000 WGUS61 KPHI 111918 FFAPHI URGENT - IMMEDIATE BROADCAST REQUESTED FLOOD WATCH NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 318 PM EDT SUN MAY 11 2008 ...HEAVY RAIN OVERNIGHT AND MONDAY COULD PRODUCE SOME AREAS OF FLOODING... .AN INTENSE LOW PRESSURE SYSTEM IN THE NORTHERN OHIO VALLEY WILL MOVE EASTWARD TONIGHT AND WEAKEN. MEANWHILE, ANOTHER LOW PRESSURE SYSTEM WILL DEVELOP TONIGHT IN THE VICINITY OF SOUTHEASTERN VIRGINA. THIS SECOND STORM WILL BECOME THE MAIN ONE OVERNIGHT AND MONDAY AS IT MOVES NORTHEASTWARD. THIS WILL BRING RAIN TO THE REGION, WHICH WILL BECOME HEAVY AT TIMES LATER TONIGHT AND MONDAY. DEZ001-MDZ008-PAZ067-070-071-120400- /O.EXT.KPHI.FA.A.0008.080512T0400Z-080512T2200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NEW CASTLE-CECIL-CHESTER-DELAWARE-PHILADELPHIA- INCLUDING THE CITIES OF...WILMINGTON...ELKTON...WEST CHESTER... MEDIA 318 PM EDT SUN MAY 11 2008 ...FLOOD WATCH NOW IN EFFECT FROM MIDNIGHT EDT TONIGHT THROUGH MONDAY AFTERNOON... THE FLOOD WATCH IS NOW IN EFFECT FOR * PORTIONS OF NORTHERN DELAWARE, NORTHEAST MARYLAND AND SOUTHEAST PENNSYLVANIA, INCLUDING THE FOLLOWING AREAS, IN NORTHERN DELAWARE, NEW CASTLE. IN NORTHEAST MARYLAND, CECIL. IN SOUTHEAST PENNSYLVANIA, CHESTER, DELAWARE AND PHILADELPHIA. * FROM MIDNIGHT EDT TONIGHT THROUGH MONDAY AFTERNOON. * RAIN BECOMING HEAVY AT TIMES TONIGHT WILL CONTINUE THROUGH ABOUT MIDDAY MONDAY, THEN BEGIN TO TAPER OFF LATE IN THE AFTERNOON. A TOTAL OF 1.0 TO 2.0 INCHES OF RAIN IS EXPECTED WITH THE POTENTIAL FOR LOCALLY HIGHER AMOUNTS. AN FEW ISOLATED THUNDERSTORMS CANNOT BE RULED OUT TONIGHT, WHICH COULD LOCALLY ENHANCE THE RAINFALL. DUE TO THE RECENT RAINFALL OVER THE AREA LATE LAST WEEK, SOME OF THE MORE VULNERABLE STREAMS AND CREEKS IN THE WATCH AREA WOULD BEGIN TO FLOOD IF AN EXCESS OF 1.5 INCHES OF RAIN FALLS. IN ADDITION, FLOODING OF POOR DRAINAGE AREAS AND SOME ROADWAYS IS POSSIBLE. A FLOOD WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR HEAVY RAIN ACROSS THE WATCH AREA, WHICH MAY LEAD TO FLOODING ALONG STREAMS AND CREEKS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP OR IF A FLOOD WARNING IS ISSUED. ONE WAY TO KEEP ABREAST OF EXISTING AND FORECASTED WATER CONDITIONS ON WATERWAYS THROUGHOUT THE REGION IS TO MONITOR THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ AVAILABLE ON OUR HOMEPAGE AT WWW.WEATHER.GOV/PHI. JUST CLICK THE AHPS ICON ON THE LEFT HAND MENU. $$ GORSE
000 WGUS61 KPHI 120138 FFAPHI FLOOD WATCH NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 938 PM EDT SUN MAY 11 2008 ...HEAVY RAIN OVERNIGHT AND MONDAY COULD PRODUCE SOME AREAS OF FLOODING... .A LOW PRESSURE SYSTEM IN OHIO WILL MOVE EASTWARD OVERNIGHT AND WEAKEN. MEANWHILE, ANOTHER LOW PRESSURE SYSTEM CONTINUES TO ORGANIZE IN THE VICINITY OF SOUTHEASTERN VIRGINA. THIS SECOND STORM WILL BECOME THE MAIN ONE OVERNIGHT AND MONDAY AS IT MOVES NORTHEASTWARD. THIS WILL BRING RAIN TO THE REGION OVERNIGHT AND MONDAY, WHICH WILL BE HEAVY AT TIMES. DEZ001-MDZ008-PAZ067-070-071-121000- /O.CON.KPHI.FA.A.0008.080512T0400Z-080512T2200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NEW CASTLE-CECIL-CHESTER-DELAWARE-PHILADELPHIA- INCLUDING THE CITIES OF...WILMINGTON...ELKTON...WEST CHESTER... MEDIA 938 PM EDT SUN MAY 11 2008 ...FLOOD WATCH REMAINS IN EFFECT THROUGH MONDAY AFTERNOON... THE FLOOD WATCH CONTINUES FOR * PORTIONS OF NORTHERN DELAWARE, NORTHEAST MARYLAND AND SOUTHEAST PENNSYLVANIA, INCLUDING THE FOLLOWING AREAS, IN NORTHERN DELAWARE, NEW CASTLE. IN NORTHEAST MARYLAND, CECIL. IN SOUTHEAST PENNSYLVANIA, CHESTER, DELAWARE AND PHILADELPHIA. * THROUGH MONDAY AFTERNOON. * RAIN OVERNIGHT WILL BE HEAVY AT TIMES AND CONTINUE THROUGH ABOUT MIDDAY MONDAY, THEN BEGIN TO TAPER OFF LATE IN THE AFTERNOON. A TOTAL OF 1.0 TO 2.0 INCHES OF RAIN IS EXPECTED WITH THE POTENTIAL FOR LOCALLY HIGHER AMOUNTS. AN ISOLATED THUNDERSTORM OR TWO CANNOT BE RULED OUT OVERNIGHT, WHICH COULD LOCALLY ENHANCE THE RAINFALL. DUE TO THE RAINFALL OVER THE AREA LATE LAST WEEK, SOME OF THE MORE VULNERABLE STREAMS AND CREEKS IN THE WATCH AREA WOULD BEGIN TO FLOOD IF AN EXCESS OF 1.5 INCHES OF RAIN FALLS. IN ADDITION, FLOODING OF POOR DRAINAGE AREAS AND SOME ROADWAYS IS POSSIBLE. A FLOOD WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR HEAVY RAIN ACROSS THE WATCH AREA, WHICH MAY LEAD TO FLOODING ALONG STREAMS AND CREEKS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP OR IF A FLOOD WARNING IS ISSUED. ONE WAY TO KEEP ABREAST OF EXISTING AND FORECASTED WATER CONDITIONS ON WATERWAYS THROUGHOUT THE REGION IS TO MONITOR THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ AVAILABLE ON OUR HOMEPAGE AT WWW.WEATHER.GOV/PHI. JUST CLICK THE AHPS ICON ON THE LEFT HAND MENU. $$ GORSE
000 WGUS61 KPHI 120740 FFAPHI FLOOD WATCH NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 340 AM EDT MON MAY 12 2008 ...POSSIBLE HEAVY RAIN THROUGH THE MORNING COULD PRODUCE SOME AREAS OF FLOODING... .A DEEP LOW PRESSURE SYSTEM WAS REORGANIZING OVER THE CENTRAL CHESAPEAKE BAY EARLY THIS MORNING. THAT LOW WILL STRENGTHEN A BIT MORE AND THEN LIFT NORTHEAST. HEAVY RAINS HAD FALLEN OVER THE MARYLAND WESTERN SHORE DURING THE OVERNIGHT HOURS...SO HEAVY RAIN IN THE WATCH AREA REMAINS POSSIBLE. DEZ001-MDZ008-PAZ067-070-071-122200- /O.CON.KPHI.FA.A.0008.000000T0000Z-080512T2200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NEW CASTLE-CECIL-CHESTER-DELAWARE-PHILADELPHIA- INCLUDING THE CITIES OF...WILMINGTON...ELKTON...WEST CHESTER... MEDIA 340 AM EDT MON MAY 12 2008 ...FLOOD WATCH REMAINS IN EFFECT THROUGH THIS AFTERNOON... THE FLOOD WATCH CONTINUES FOR * PORTIONS OF NORTHERN DELAWARE...NORTHEAST MARYLAND AND SOUTHEAST PENNSYLVANIA...INCLUDING THE FOLLOWING AREAS...IN NORTHERN DELAWARE...NEW CASTLE. IN NORTHEAST MARYLAND...CECIL. IN SOUTHEAST PENNSYLVANIA...CHESTER...DELAWARE AND PHILADELPHIA. * THROUGH THIS AFTERNOON * RAINFALL AMOUNTS THROUGH 200 AM EDT RANGED FROM ONLY AROUND A TENTH OF AN INCH OVER PORTIONS OF PHILADELPHIA...DELAWARE AND CHESTER COUNTIES IN SOUTHEASTERN PENNSYLVANIA TO AROUND AN INCH OVER PORTIONS OF CECIL COUNTY IN NORTHEAST MARYLAND AND NEW CASTLE COUNTY IN NORTHERN DELAWARE. HOWEVER...THERE WERE REPORTS OF RAINFALL AMOUNTS IN EXCESS OF TWO INCHES ON THE WESTERN SIDE OF THE CHESAPEAKE BAY. RADAR EARLY THIS MORNING INDICATED THAT SOME WEAK CONVECTIVE CELLS WERE DEVELOPING UPSTREAM OF THE WATCH AREA...AND SURFACE ANALYSIS SHOWED DEEP LOW PRESSURE WAS ORGANIZING OVER THE CENTRAL CHESAPEAKE BAY. THE POTENTIAL STILL EXISTS FOR SUFFICIENT RAINFALL TO TRIGGER FLOODING OF THE FLASHIER CREEKS AND STREAMS IN OUR AREA. THEREFORE...THE WATCH IS MAINTAINED. A FLOOD WATCH MEANS THAT FLOODING ALONG STREAMS AND CREEKS IS POSSIBLE...BUT NOT IMMINENT. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP OR IF A FLOOD WARNING IS ISSUED. ONE WAY TO KEEP ABREAST OF EXISTING AND FORECASTED WATER CONDITIONS ON WATERWAYS THROUGHOUT THE REGION IS TO MONITOR THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ AVAILABLE ON OUR HOMEPAGE AT WWW.WEATHER.GOV/PHI. JUST CLICK THE AHPS ICON ON THE LEFT HAND MENU. $$ MPD
000 WGUS61 KPHI 121331 FFAPHI FLOOD WATCH NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 931 AM EDT MON MAY 12 2008 DEZ001-MDZ008-PAZ067-070-071-121430- /O.CAN.KPHI.FA.A.0008.000000T0000Z-080512T2200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NEW CASTLE-CECIL-CHESTER-DELAWARE-PHILADELPHIA- INCLUDING THE CITIES OF...WILMINGTON...ELKTON...WEST CHESTER... MEDIA 930 AM EDT MON MAY 12 2008 ...FLOOD WATCH IS CANCELLED... THE FLOOD WATCH FOR PORTIONS OF NORTHERN DELAWARE...NORTHEAST MARYLAND AND SOUTHEAST PENNSYLVANIA HAS BEEN CANCELLED. HEAVY FLOODING RAINS ARE NO LONGER EXPECTED IN THE WATCH AREA. $$ TFG
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 3:34 PM EDT | Coastal Flood Advisory | PHI | Caroline, Cecil, Kent, Queen Anne's, Talbot | 25 hr |
| May 10, 9:05 PM EDT | Coastal Flood Statement | PHI | Sussex | 6 hr |
| May 11, 5:15 AM EDT | Coastal Flood Watch | PHI | Sussex | 10 hr |
| May 11, 5:15 AM EDT | Coastal Flood Advisory | PHI | Sussex | 10 hr |
| May 11, 3:34 PM EDT | Coastal Flood Warning | PHI | Kent, New Castle, Sussex | 40 hr |
Nearby
Flood Watches in Pennsylvania, 2008Flood Watches in Maryland, 2008Flood Watches in Delaware, 2008Every flood watch in 2008
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.