Alert archive / Pennsylvania / Areal Flood Advisories in 2021

Areal Flood Advisory 178, NWS Philadelphia/Mount Holly

September 13, 2021Carbon County, Monroe County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood advisory at Sep 13, 2021, 8:51 PM EDT for Carbon County, Monroe County, Pennsylvania. It was in force for 108 min.

The area

The outline as issued.

The facts

Issued
Sep 13, 2021, 8:51 PM EDT (00:51 UTC)
Expired
Sep 13, 2021, 10:39 PM EDT
In force
108 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Carbon County, PA, Monroe County, PA

The radar

The Binghamton radar (KBGM), 129 km from the middle of the area, began a volume at 00:54 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, 0.9 hours before the alert went out and 231 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 00:00Z on 2021-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 90 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 00:00Z on 2021-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 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
90 J/kg
Mixed-layer CIN
-236 J/kg
Mixed-layer LCL
1411 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

412 
WGUS81 KPHI 140051
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
851 PM EDT Mon Sep 13 2021

PAC025-089-140400-
/O.NEW.KPHI.FA.Y.0178.210914T0051Z-210914T0400Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon PA-Monroe PA-
851 PM EDT Mon Sep 13 2021

The National Weather Service in Mount Holly has issued a

* Flood Advisory for...
  Carbon County in northeastern Pennsylvania...
  Monroe County in northeastern Pennsylvania...

* Until midnight EDT.

* At 851 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Up to an inch of rain has fallen. Minor flooding is 
  ongoing or expected to begin shortly in the advisory area.

* Some locations that may experience flooding include...
  Lehighton, Mount Pocono, East Stroudsburg, Tobyhanna, Palmerton, 
  Jim Thorpe, Nesquehoning, Weatherly, Delaware Water Gap, Jonas, 
  Meckesville, and Sun Valley.

This includes the following highways...
	Interstate 80 in Pennsylvania between mile markers 277 and 313.
	Interstate 380 in Pennsylvania between mile markers 0 and 13.
	Northeast Extension between mile markers 72 and 98.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4074 7575 4092 7598 4101 7573 4103 7574
      4103 7576 4105 7577 4109 7577 4113 7569
      4113 7567 4112 7566 4112 7563 4116 7560
      4117 7556 4122 7554 4122 7552 4123 7551
      4124 7537 4106 7501 4104 7503

$$

MPS
2 follow-up statements
727 
WGUS81 KPHI 140207
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
1007 PM EDT Mon Sep 13 2021

PAC025-089-140400-
/O.CON.KPHI.FA.Y.0178.000000T0000Z-210914T0400Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon PA-Monroe PA-
1007 PM EDT Mon Sep 13 2021

...FLOOD ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT EDT TONIGHT FOR 
CARBON AND MONROE COUNTIES...

At 1007 PM EDT, Although the heavy rain and thunderstorms has moved 
out of the advisory area, as much as 1 to 1.5 inches of rain fell. 
Minor flooding is ongoing or expected to begin shortly in the 
advisory area.

Some locations that may experience flooding include...
  Lehighton, Mount Pocono, East Stroudsburg, Tobyhanna, Palmerton, 
  Jim Thorpe, Nesquehoning, Weatherly, Delaware Water Gap, Jonas, 
  Meckesville, and Sun Valley.

This includes the following highways...
	Interstate 80 in Pennsylvania between mile markers 277 and 314.
	Interstate 380 in Pennsylvania between mile markers 0 and 13.
	Northeast Extension between mile markers 72 and 97.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4074 7575 4092 7598 4101 7573 4103 7574
      4103 7576 4105 7577 4109 7577 4113 7569
      4113 7567 4112 7566 4112 7563 4116 7560
      4117 7556 4122 7554 4122 7552 4123 7551
      4124 7537 4106 7501 4104 7503

$$

MPS
475 
WGUS81 KPHI 140239
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
1039 PM EDT Mon Sep 13 2021

PAC025-089-140249-
/O.CAN.KPHI.FA.Y.0178.000000T0000Z-210914T0400Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon PA-Monroe PA-
1039 PM EDT Mon Sep 13 2021

...FLOOD ADVISORY IS CANCELLED FOR CARBON AND MONROE COUNTIES...

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

LAT...LON 4074 7575 4092 7598 4101 7573 4103 7574
      4103 7576 4105 7577 4109 7577 4113 7569
      4113 7567 4112 7566 4112 7563 4116 7560
      4117 7556 4122 7554 4122 7552 4123 7551
      4124 7537 4106 7501 4104 7503

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 8:16 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe44 min
Sep 13, 8:41 PM EDTSevere Thunderstorm WarningPHICarbon, Lehigh, Monroe, Northampton49 min
Sep 13, 9:03 PM EDTAreal Flood AdvisoryPHIMonroe, Northampton109 min
Sep 13, 9:12 PM EDTFlash Flood WarningPHINorthampton114 min
Sep 13, 9:21 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton38 min

Nearby

Areal Flood Advisories in Pennsylvania, 2021Every areal flood advisory in 2021

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.