Alert archive / Pennsylvania / Flash Flood Warnings in 2018
Flash Flood Warning 78, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 21, 2018, 11:08 PM EDT for Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 4 hr. 18 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
- Aug 21, 2018, 11:08 PM EDT (03:08 UTC)
- Expired
- Aug 22, 2018, 3:00 AM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Bucks County, PA, Lehigh County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 112 km from the middle of the area, began a volume at 03:09 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 22, 12:00 AM EDT | HEAVY RAIN 2.24 | Neffs, PA | |
| Aug 22, 12:00 AM EDT | HEAVY RAIN 3.04 | 1 S Coffeetown, PA | |
| Aug 22, 12:00 AM EDT | HEAVY RAIN 3.54 | 2 Nw Upper Milford Twp, PA | |
| Aug 22, 12:25 AM EDT | FLOOD | South Whitehall Twp, PA | NUMEROUS ROAD CLOSURES DUE TO HIGH WATER IN MACUNGIE AND SOUTH WHITEHALL TWPS. SEVERAL CARS STUCK IN HIGH WATER. |
| Aug 22, 12:30 AM EDT | FLOOD | West Rockhill Twp, PA | HEAVY RAIN AND FLOOD WATERS KNOCKED DOWN A TREE ON FINLAND ROAD AND RIDGE VALLEY ROAD BETWEEN RIDGE ROAD AND ALLENTOWN ROAD. ALL LANES CLOSED. TIME ESTIMATED. |
| Aug 22, 12:45 AM EDT | FLOOD | 1 Sw Dublin, PA | HEAVY RAIN AND FLOODING KNOCKED DOWN A TREE ON DUBLIN ROAD AND CALLOWHILL ROAD BETWEEN WELCOME HOUSE ROAD AND BYPASS ROAD. ALL LANES CLOSED. TIME ESTIMATED. |
| Aug 22, 12:45 AM EDT | FLOOD | 2 Sw Lehigh Twp, PA | RIVERVIEW DRIVE IN LEHIGH TWP CLOSED FROM FLOOD WATERS. |
| Aug 22, 12:45 AM EDT | FLOOD | East Allen Twp, PA | STREET FLOODING AND ROAD CLOSURES IN EAST ALLEN TWP. |
| Aug 22, 12:45 AM EDT | FLOOD | Forks, PA | FLOODING ON BUSHKILL DRIVE. |
| Aug 22, 12:55 AM EDT | HEAVY RAIN 2.19 | Allentown-Queen City, PA | |
| Aug 22, 1:28 AM EDT | FLOOD | 3 Ne Ancient Oaks, PA | MINESITE ROAD CLOSED BETWEEN HAMILTON BOULEVARD AND CENTRONIA ROAD DUE TO FLOODING. |
| Aug 22, 1:28 AM EDT | FLOOD | 3 Ne Ancient Oaks, PA | MINESITE ROAD CLOSED BETWEEN HAMILTON BOULEVARD AND CETRONIA ROAD DUE TO FLOODING. |
| Aug 22, 1:30 AM EDT | FLASH FLOOD | 1 Wsw Emmaus, PA | FLOODING ON LEHIGH STREET BETWEEN MILL RACE ROAD AND CEDAR CREST BOULEVARD. ALL LANES CLOSED. TIME BASED ON RADAR AND BASED ON WHEN OTHER REPORTS WERE BEING RECEIVED. |
| Aug 22, 1:30 AM EDT | FLASH FLOOD | Lower Macungie Twp, PA | VEHICLE SWEPT INTO A CORNFIELD FROM SWIFTLY FLOWING FLOOD WATERS ON SAUERKRAUT LANE. TIME ESTIMATED FROM RADAR. |
| Aug 22, 1:30 AM EDT | FLASH FLOOD | North Whitehall Twp, PA | VEHICLE STUCK IN FLOOD WATERS AT THE INTERSECTION OF ROUTE 145 AND CLEARVIEW ROAD. A CAR WAS STUCK IN TWO FEET OF WATER ON THE EASTBOUND RAMP OF INTERSTATE 78 FROM ROUTE 100. TIME ESTIMATED FROM RADAR. |
| Aug 22, 1:51 AM EDT | HEAVY RAIN 2.43 | Lehigh Valley Intl Airp, PA | SIX-HOUR RAINFALL TOTAL. |
| Aug 22, 2:33 AM EDT | FLASH FLOOD | 2 Sse Upper Macungie Tw, PA | CENTRONIA ROAD CLOSED NEAR THE GRANGE ROAD AND TREXLERTOWN ROAD INTERSECTIONS. |
| Aug 22, 2:33 AM EDT | FLASH FLOOD | 2 Sse Upper Macungie Tw, PA | CETRONIA ROAD CLOSED NEAR THE GRANGE ROAD AND TREXLERTOWN ROAD INTERSECTIONS. |
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 00:00Z, 3.1 hours before the alert went out and 209 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
- 4 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 554 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 69 m²/s²
- 0-3 km storm-relative helicity
- 101 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
891
WGUS51 KPHI 220308
FFWPHI
PAC017-077-095-220700-
/O.NEW.KPHI.FF.W.0078.180822T0308Z-180822T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1108 PM EDT TUE AUG 21 2018
The National Weather Service in Mount Holly NJ has issued a
* Flash Flood Warning for...
Lehigh County in eastern Pennsylvania...
Northwestern Bucks County in southeastern Pennsylvania...
Northampton County in eastern Pennsylvania...
* Until 300 AM EDT.
* At 1106 PM EDT, Doppler radar indicated heavy rain across the
warned area. Up to one and a half inches of rain has already
fallen with up to two inches of additional rainfall possible.
Flash flooding is expected to begin shortly in the areas of
heaviest rain.
* Some locations that could experience flooding include...
Allentown, Easton, Bethlehem, Forks, Emmaus, Northampton,
Quakertown, Perkasie, Wilson, Souderton, Bedminster, Hellertown,
Nazareth, Slatington, Chalfont, Wind Gap, Bath, Dublin, Walnutport
and Ferndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.
&&
LAT...LON 4079 7562 4081 7554 4083 7538 4086 7532
4076 7518 4068 7520 4068 7517 4065 7520
4057 7519 4058 7512 4055 7508 4026 7523
4062 7581
$$
CMS3 follow-up statements
587
WGUS71 KPHI 220423
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1223 AM EDT WED AUG 22 2018
PAC017-077-095-220700-
/O.CON.KPHI.FF.W.0078.000000T0000Z-180822T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-Bucks PA-Northampton PA-
1223 AM EDT WED AUG 22 2018
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 300 AM EDT FOR
LEHIGH...NORTHWESTERN BUCKS AND NORTHAMPTON COUNTIES...
At 1222 AM EDT, Doppler radar and automated rain gauges indicated
that heavy rain was falling over the area. Up to three inches of
rain have already fallen, especially near and to the south of
Allentown. Flash flooding is imminent.
Some locations that could experience flooding include...
Allentown, Easton, Bethlehem, Forks, Emmaus, Northampton, Quakertown,
Perkasie, Wilson, Souderton, Bedminster, Hellertown, Nazareth,
Slatington, Chalfont, Wind Gap, Bath, Dublin, Walnutport and
Ferndale.
Additional rainfall amounts of one to two inches are possible in the
warned area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 4079 7562 4081 7554 4083 7538 4086 7532
4076 7518 4068 7520 4068 7517 4065 7520
4057 7519 4058 7512 4055 7508 4026 7523
4062 7581
$$
CMS631
WGUS71 KPHI 220626
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
226 AM EDT WED AUG 22 2018
PAC017-077-095-220700-
/O.CON.KPHI.FF.W.0078.000000T0000Z-180822T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-Bucks PA-Northampton PA-
226 AM EDT WED AUG 22 2018
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 300 AM EDT FOR
LEHIGH...NORTHWESTERN BUCKS AND NORTHAMPTON COUNTIES...
At 225 AM EDT, local law enforcement reported flash flooding in
Upper Macungie and Lower Macungie Townships...with several roads
closed. Additionally, the Perkiomen Creek gauge in Dublin in Bucks
County is approaching flood stage. Up to three inches of rain have
already fallen. Flash flooding is already occurring.
Some locations that could experience flooding include...
Allentown, Easton, Bethlehem, Forks, Emmaus, Northampton, Quakertown,
Perkasie, Wilson, Souderton, Bedminster, Hellertown, Nazareth,
Slatington, Chalfont, Wind Gap, Bath, Dublin, Walnutport and
Ferndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 4079 7562 4081 7554 4083 7538 4086 7532
4076 7518 4068 7520 4068 7517 4065 7520
4057 7519 4058 7512 4055 7508 4026 7523
4062 7581
$$
CMS027
WGUS71 KPHI 220655
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
255 AM EDT WED AUG 22 2018
PAC017-077-095-220704-
/O.EXP.KPHI.FF.W.0078.000000T0000Z-180822T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-Bucks PA-Northampton PA-
255 AM EDT WED AUG 22 2018
...THE FLASH FLOOD WARNING FOR LEHIGH...NORTHWESTERN BUCKS AND
NORTHAMPTON COUNTIES WILL EXPIRE AT 300 AM EDT...
A flood warning is now in effect until 645 am. Flooding continues in
much of the area with several road closures in place. Use extreme
caution traveling in this area.
LAT...LON 4079 7562 4081 7554 4083 7538 4086 7532
4076 7518 4068 7520 4068 7517 4065 7520
4057 7519 4058 7512 4055 7508 4026 7523
4062 7581
$$
CMSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 8:53 PM EDT | Areal Flood Advisory | PHI | Berks, Chester, Montgomery | 5 hr |
| Aug 21, 10:16 PM EDT | Flash Flood Warning | PHI | Berks, Chester, Montgomery | 7 hr |
| Aug 21, 10:46 PM EDT | Areal Flood Advisory | PHI | Bucks, Lehigh, Northampton | 4 hr |
| Aug 21, 11:18 PM EDT | Areal Flood Advisory | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Aug 21, 11:47 PM EDT | Areal Flood Advisory | PHI | Northampton | 4 hr |
| Aug 22, 1:14 AM EDT | Areal Flood Advisory | PHI | Monroe | 4 hr |
| Aug 22, 2:54 AM EDT | Areal Flood Warning | PHI | Bucks, Lehigh, Northampton | 8 hr |
| Aug 22, 4:36 AM EDT | River Flood Warning | PHI | Montgomery | 6 hr |
| Aug 22, 5:14 AM EDT | Areal Flood Warning | PHI | Berks, Chester, Montgomery | 4 hr |
| Aug 22, 10:04 AM EDT | River Flood Warning | PHI | Chester, Montgomery, Philadelphia | 5 hr |
Nearby
Flash Flood Warnings in Pennsylvania, 2018Every flash flood warning in 2018
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.