Alert archive / Pennsylvania / Areal Flood Advisories in 2021

Areal Flood Advisory 149, NWS Philadelphia/Mount Holly

August 27, 2021Carbon County, Monroe County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood advisory at Aug 27, 2021, 1:20 PM EDT for Carbon County, Monroe County, Pennsylvania. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Aug 27, 2021, 1:20 PM EDT (17:20 UTC)
Expired: Aug 27, 2021, 3:22 PM EDT
In force: 2 hr
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 17:20 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 12:00Z, 5.3 hours before the alert went out and 229 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1159 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 1043 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 22 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

273 
WGUS81 KPHI 271720
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
120 PM EDT Fri Aug 27 2021

PAC025-089-272030-
/O.NEW.KPHI.FA.Y.0149.210827T1720Z-210827T2030Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon PA-Monroe PA-
120 PM EDT Fri Aug 27 2021

The National Weather Service in Mount Holly has issued a

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

* Until 430 PM EDT.

* At 120 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Minor flooding is ongoing or expected to begin 
  shortly in the advisory area. Between 1 and 2 inches of rain have 
  fallen. Additional rainfall is expected.

* Some locations that may experience flooding include...
  Mount Pocono, Tobyhanna, Jim Thorpe, Nesquehoning, Weatherly, 
  Pocono Raceway, Meckesville, Lake Harmony, Blakeslee, 
  Albrightsville, Long Pond, and Jonas.

This includes the following highways...
	Interstate 80 in Pennsylvania between mile markers 277 and 302.
	Interstate 380 in Pennsylvania between mile markers 0 and 13.
	Northeast Extension between mile markers 81 and 98.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 4112 7563 4122 7554 4125 7513 4115 7516
      4114 7509 4080 7584 4091 7600 4101 7573
      4105 7577 4109 7577 4113 7569

$$

Kruzdlo

1 follow-up statement

263 
WGUS81 KPHI 271922
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
322 PM EDT Fri Aug 27 2021

PAC025-089-271932-
/O.CAN.KPHI.FA.Y.0149.000000T0000Z-210827T2030Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon PA-Monroe PA-
322 PM EDT Fri Aug 27 2021

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

Although showers still persist across portions of the advisory area, 
the heaviest rain has ended. At this time, flooding is no longer
expected to pose a threat.

LAT...LON 4112 7563 4122 7554 4125 7513 4115 7516
      4114 7509 4080 7584 4091 7600 4101 7573
      4105 7577 4109 7577 4113 7569

$$

Kruzdlo

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 1:33 PM EDT	Areal Flood Advisory	PHI	Bucks, Delaware, Philadelphia	83 min
Aug 27, 1:36 PM EDT	Special Weather Statement	PHI	Monroe	24 min
Aug 27, 1:52 PM EDT	Severe Thunderstorm Warning	PHI	Chester	53 min
Aug 27, 2:12 PM EDT	Special Weather Statement	PHI	Northampton	33 min
Aug 27, 2:18 PM EDT	Areal Flood Advisory	PHI	Chester	93 min
Aug 27, 2:32 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe, Northampton	28 min
Aug 27, 2:33 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe, Northampton	109 min
Aug 27, 2:42 PM EDT	Severe Thunderstorm Warning	PHI	Chester	14 min
Aug 27, 3:07 PM EDT	Severe Thunderstorm Warning	PHI	Northampton	24 min
Aug 27, 3:44 PM EDT	Special Weather Statement	PHI	Delaware	31 min
Aug 27, 5:29 PM EDT	Areal Flood Advisory	PHI	Bucks, Montgomery	3 hr
Aug 27, 6:29 PM EDT	Areal Flood Advisory	PHI	Berks	3 hr
Aug 27, 6:41 PM EDT	Special Weather Statement	PHI	Berks	34 min
Aug 27, 7:17 PM EDT	Flash Flood Warning	PHI	Berks	3 hr

Nearby

Areal Flood Advisories in Pennsylvania, 2021 Every 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.