Alert archive / Pennsylvania / Flash Flood Warnings in 2019

Flash Flood Warning 20, NWS Philadelphia/Mount Holly

June 18, 2019Hunterdon County, Warren County, New Jersey; Bucks County, Lehigh County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 18, 2019, 3:57 PM EDT for Hunterdon County, Warren County, New Jersey; Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 4 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 18, 2019, 3:57 PM EDT (19:57 UTC)
Expired
Jun 18, 2019, 8:00 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Warren County, NJ, Bucks County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 98 km from the middle of the area, began a volume at 19:57 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.

What was reported inside it

TimeReportWhereRemark
Jun 18, 4:34 PM EDTFLOOD2 Nnw Hampton, NJSTREET FLOODING REPORTED ON RYMON ROAD IN WASHINGTON TWP.
Jun 18, 6:08 PM EDTHEAVY RAIN 2.29Stewartsville, NJSINCE MIDNIGHT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.0 hours before the alert went out and 192 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.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2019-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 78 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2019-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
78 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
453 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

082 
WGUS51 KPHI 181957
FFWPHI
NJC019-041-PAC017-077-095-190000-
/O.NEW.KPHI.FF.W.0020.190618T1957Z-190619T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
357 PM EDT Tue Jun 18 2019

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northwestern Hunterdon County in northwestern New Jersey...
  Southwestern Warren County in northwestern New Jersey...
  East central Lehigh County in eastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  Southeastern Northampton County in eastern Pennsylvania...

* Until 800 PM EDT.

* At 355 PM EDT, Doppler radar indicated heavy rain across the 
  warned area. Up to two inches of rain fell with earlier storms. 
  Flash flooding is expected to begin shortly in the areas of 
  heaviest rain.

* Some locations that could experience flooding include...
  Allentown, Easton, Bethlehem, Wilson, Hellertown, Clinton, Alpha,
  Glen Gardner, Ferndale, Hampton, West Easton, Milford, Bloomsbury,
  Riegelsville, Glendon, Pleasant Valley, Springtown, Old Orchard,
  Lehigh University and Phillipsburg.

Additional rainfall amounts of up to one inch are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4076 7493 4058 7492 4049 7540 4063 7544

$$

SFJ
3 follow-up statements
015 
WGUS71 KPHI 182104
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
504 PM EDT Tue Jun 18 2019

NJC019-041-PAC017-077-095-190000-
/O.CON.KPHI.FF.W.0020.000000T0000Z-190619T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Lehigh PA-Bucks PA-Northampton PA-
504 PM EDT Tue Jun 18 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM EDT FOR
NORTHWESTERN HUNTERDON...SOUTHWESTERN WARREN...EAST CENTRAL LEHIGH...
NORTHWESTERN BUCKS AND SOUTHEASTERN NORTHAMPTON COUNTIES...

At 503 PM EDT, Doppler radar indicated another round of 
thunderstorms producing heavy rain crossing the warned area.  Flash 
flooding is expected to begin shortly.

Some locations that could experience flooding include...
Allentown, Easton, Bethlehem, Wilson, Hellertown, Clinton, Alpha,
Glen Gardner, Ferndale, Hampton, West Easton, Milford, Bloomsbury,
Riegelsville, Glendon, Pleasant Valley, Springtown, Old Orchard,
Lehigh University and Phillipsburg.

Additional rainfall amounts of one to two inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4076 7493 4058 7492 4049 7540 4063 7544

$$

SFJ
043 
WGUS71 KPHI 182217
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
617 PM EDT Tue Jun 18 2019

NJC019-041-PAC017-077-095-190000-
/O.CON.KPHI.FF.W.0020.000000T0000Z-190619T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Lehigh PA-Bucks PA-Northampton PA-
617 PM EDT Tue Jun 18 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM EDT FOR
NORTHWESTERN HUNTERDON...SOUTHWESTERN WARREN...EAST CENTRAL LEHIGH...
NORTHWESTERN BUCKS AND SOUTHEASTERN NORTHAMPTON COUNTIES...

At 616 PM EDT, Doppler radar indicated the heavy rain had left the 
warned area. However, it will take time for water to recede. 
Therefore the threat for flash flooding continues. Up to three 
inches of rain have already fallen.

Some locations that could experience flooding include...
Allentown, Easton, Bethlehem, Wilson, Hellertown, Clinton, Alpha,
Glen Gardner, Ferndale, Hampton, West Easton, Milford, Bloomsbury,
Riegelsville, Glendon, Pleasant Valley, Springtown, Old Orchard,
Lehigh University and Phillipsburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4076 7493 4058 7492 4049 7540 4063 7544

$$

SFJ
137 
WGUS71 KPHI 182351
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
751 PM EDT Tue Jun 18 2019

NJC019-041-PAC017-077-095-190000-
/O.EXP.KPHI.FF.W.0020.000000T0000Z-190619T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Lehigh PA-Bucks PA-Northampton PA-
751 PM EDT Tue Jun 18 2019

...THE FLASH FLOOD WARNING FOR NORTHWESTERN HUNTERDON...SOUTHWESTERN
WARREN...EAST CENTRAL LEHIGH...NORTHWESTERN BUCKS AND SOUTHEASTERN
NORTHAMPTON COUNTIES WILL EXPIRE AT 800 PM EDT...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 4076 7493 4058 7492 4049 7540 4063 7544

$$

SFJ

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 17, 10:28 PM EDTSpecial Marine WarningPHI32 min
Jun 18, 11:07 AM EDTAreal Flood AdvisoryPHIHunterdon, Morris, Somerset, Sussex, Warren4 hr
Jun 18, 12:38 PM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Middlesex, Morris, Somerset7 hr
Jun 18, 1:51 PM EDTFlash Flood WarningPHIMercer, Middlesex, Somerset4 hr
Jun 18, 2:06 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Monmouth, Somerset54 min
Jun 18, 2:11 PM EDTAreal Flood AdvisoryPHIMercer, Middlesex, Monmouth, Ocean4 hr
Jun 18, 2:35 PM EDTSpecial Marine WarningPHI70 min
Jun 18, 2:36 PM EDTFlash Flood WarningPHIMiddlesex, Monmouth3 hr
Jun 18, 3:26 PM EDTFlash Flood WarningPHIHunterdon, Mercer, Somerset4 hr
Jun 18, 3:41 PM EDTAreal Flood AdvisoryPHIHunterdon, Morris, Somerset, Sussex, Warren4 hr
Jun 18, 4:25 PM EDTSpecial Weather StatementPHIMercer35 min
Jun 18, 5:00 PM EDTAreal Flood AdvisoryPHIBurlington, Mercer, Monmouth, Ocean67 min
Jun 18, 6:39 PM EDTAreal Flood WarningPHIHunterdon, Somerset4 hr
Jun 18, 7:24 PM EDTAreal Flood WarningPHIHunterdon, Mercer, Somerset4 hr
Jun 18, 5:09 PM EDTFlash Flood WarningPHIBerks, Lehigh, Northampton3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2019Flash Flood Warnings in New Jersey, 2019Every flash flood warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.