Alert archive / Pennsylvania / Flash Flood Warnings in 2018
Flash Flood Warning 39, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 22, 2018, 9:40 PM EDT for Lehigh County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 22, 2018, 9:40 PM EDT (01:40 UTC)
- Expired
- Jul 23, 2018, 1:09 AM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Lehigh County, PA
The radar
The Philadelphia radar (KDIX), 135 km from the middle of the area, began a volume at 01:42 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
Brookhaven, NY (KOKX), launched 00:00Z, 1.7 hours before the alert went out and 236 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
- 237 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 576 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 187 m²/s²
- 0-3 km storm-relative helicity
- 197 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted.
036
WGUS51 KPHI 230140
FFWPHI
PAC077-230545-
/O.NEW.KPHI.FF.W.0039.180723T0140Z-180723T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
940 PM EDT SUN JUL 22 2018
The National Weather Service in Mount Holly NJ has issued a
* Flash Flood Warning for...
Lehigh County in eastern Pennsylvania...
* Until 145 AM EDT.
* At 938 PM EDT, Doppler radar indicated showers and thunderstorms
producing very heavy rain across the warned area. A quick 1 to 2
inches of rain will result in flash flooding, and this rainfall is
on top of the heavy rain that occurred earlier over this same area.
* Some locations that could experience flooding include...
Allentown, Slatington, Walnutport, Neffs, Wanamakers, Coffeetown,
New Tripoli, Jordan Valley, Ancient Oaks, Emerald, Schnecksville,
Claussville, Macungie and Alburtis.
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 4070 7583 4077 7570 4079 7561 4076 7561
4074 7559 4072 7556 4074 7553 4072 7552
4046 7555 4068 7589
$$
Gorse2 follow-up statements
397
WGUS71 KPHI 230215
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1015 PM EDT SUN JUL 22 2018
PAC077-230545-
/O.CON.KPHI.FF.W.0039.000000T0000Z-180723T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-
1015 PM EDT SUN JUL 22 2018
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 AM EDT FOR
LEHIGH COUNTY...
At 1013 PM EDT, Doppler radar indicated showers and thunderstorms
producing heavy rain continue to move across the warned area,
however the more intense rainfall rates are now shifting north of
the area. A quick 1 to 2 inches of rain will lead to flash flooding
in some areas.
Some locations that could experience flooding include...
Allentown, Slatington, Walnutport, Neffs, Wanamakers, Coffeetown, New
Tripoli, Jordan Valley, Ancient Oaks, Emerald, Schnecksville,
Claussville, Macungie and Alburtis.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 4070 7583 4077 7570 4079 7561 4076 7561
4074 7559 4072 7556 4074 7553 4072 7552
4046 7555 4068 7589
$$
Gorse977
WGUS71 KPHI 230509
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
109 AM EDT MON JUL 23 2018
PAC077-230519-
/O.CAN.KPHI.FF.W.0039.000000T0000Z-180723T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-
109 AM EDT MON JUL 23 2018
...THE FLASH FLOOD WARNING FOR LEHIGH COUNTY IS CANCELLED...
The heavy rain has ended. Only scattered showers are expected the
next few hours. Flooding is no longer expected to pose a threat.
Please continue to heed any remaining road closures.
LAT...LON 4070 7583 4077 7570 4079 7561 4076 7561
4074 7559 4072 7556 4074 7553 4072 7552
4046 7555 4068 7589
$$
POThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 22, 8:18 PM EDT | Areal Flood Warning | PHI | Chester | 117 min |
| Jul 22, 8:43 PM EDT | Flash Flood Warning | PHI | Chester | 4 hr |
| Jul 22, 8:54 PM EDT | Flash Flood Warning | PHI | Berks, Chester | 4 hr |
| Jul 22, 10:21 PM EDT | Special Weather Statement | PHI | Monroe | 54 min |
| Jul 22, 11:18 PM EDT | Areal Flood Advisory | PHI | Carbon, Monroe, Northampton | 3 hr |
| Jul 23, 12:19 AM EDT | River Flood Warning | PHI | Chester | 5 hr |
| Jul 23, 3:45 AM EDT | Flash Flood Watch | PHI | Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more | 68 hr |
| Jul 23, 7:00 AM EDT | River Flood Warning | PHI | Chester, Delaware | 9 hr |
| Jul 23, 12:58 PM EDT | Special Weather Statement | PHI | Chester | 32 min |
| Jul 23, 1:01 PM EDT | Areal Flood Advisory | PHI | Chester | 34 min |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.