Alert archive / New Jersey / Areal Flood Advisories in 2020

Areal Flood Advisory 209, NWS Philadelphia/Mount Holly

December 25, 2020Mercer County, Middlesex County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood advisory at Dec 25, 2020, 5:43 AM EST for Mercer County, Middlesex County, Somerset County, New Jersey. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Dec 25, 2020, 5:43 AM EST (10:43 UTC)
Expired: Dec 25, 2020, 8:35 AM EST
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Mercer County, NJ, Middlesex County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 55 km from the middle of the area, began a volume at 10:42 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, 10.7 hours before the alert went out and 152 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 784 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 682 m²/s²
0-3 km storm-relative helicity: 727 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this areal flood advisory went out at Dec 25, 5:04 AM EST, 39 minutes earlier.

Area forecast discussion, Dec 25, 5:04 AM EST, 39 minutes before

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Hazardous weather outlook, Dec 25, 4:58 AM EST, 45 minutes before

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In the hours before

Local storm report, Dec 25, 4:32 AM EST, 1 hour 11 minutes before

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Local storm report, Dec 25, 4:37 AM EST, 1 hour 6 minutes before

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Local storm report, Dec 25, 4:38 AM EST, 1 hour 5 minutes before

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Local storm report, Dec 25, 4:43 AM EST, 1 hour before

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Local storm report, Dec 25, 4:44 AM EST, 59 minutes before

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Local storm report, Dec 25, 4:46 AM EST, 57 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 24, 8:39 PM EST	Areal Flood Advisory	PHI	Cumberland, Gloucester, Salem	6 hr
Dec 24, 9:08 PM EST	Coastal Flood Advisory	PHI	Burlington, Camden	14 hr
Dec 24, 9:16 PM EST	Areal Flood Advisory	PHI	Hunterdon, Warren	3 hr
Dec 24, 9:38 PM EST	Areal Flood Warning	PHI	Camden	14 hr
Dec 24, 11:10 PM EST	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Salem	4 hr
Dec 24, 11:48 PM EST	Areal Flood Warning	PHI	Hunterdon, Mercer, Morris, Somerset, Warren	15 hr
Dec 25, 12:00 AM EST	Areal Flood Warning	PHI	Middlesex, Somerset	6 hr
Dec 25, 12:03 AM EST	Coastal Flood Statement	PHI	Ocean	12 hr
Dec 25, 1:37 AM EST	Areal Flood Advisory	PHI	Morris, Sussex, Warren	10 hr
Dec 25, 1:56 AM EST	Areal Flood Warning	PHI	Burlington, Camden	7 hr
Dec 25, 2:05 AM EST	River Flood Warning	PHI	Hunterdon, Somerset	4 hr
Dec 25, 3:22 AM EST	Gale Warning	PHI		6 hr
Dec 25, 3:22 AM EST	Small Craft Advisory	PHI		51 hr
Dec 25, 7:25 AM EST	River Flood Warning	PHI	Morris, Passaic	37 hr
Dec 25, 11:27 AM EST	Areal Flood Warning	PHI	Sussex, Warren	16 hr
Dec 25, 12:17 PM EST	River Flood Warning	PHI	Middlesex, Somerset	9 hr
Dec 25, 12:53 PM EST	Coastal Flood Statement	PHI	Burlington, Ocean	4 hr
Dec 25, 2:11 PM EST	River Flood Warning	PHI	Middlesex, Somerset	7 hr
Dec 25, 2:12 PM EST	River Flood Warning	PHI	Somerset	20 hr
Dec 25, 2:26 PM EST	River Flood Warning	PHI	Hunterdon, Somerset	3 hr
Dec 25, 6:25 PM EST	River Flood Warning	PHI	Morris	21 hr
Dec 24, 8:47 PM EST	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery, Philadelphia	6 hr
Dec 24, 10:09 PM EST	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	6 hr
Dec 24, 10:21 PM EST	Areal Flood Warning	PHI	Bucks	14 hr
Dec 24, 10:30 PM EST	River Flood Warning	PHI	Delaware	10 hr
Dec 24, 11:26 PM EST	River Flood Warning	PHI	Chester	13 hr
Dec 24, 11:54 PM EST	Areal Flood Warning	PHI	Lehigh, Monroe, Northampton	12 hr
Dec 25, 12:36 AM EST	River Flood Warning	PHI	Montgomery	13 hr
Dec 25, 12:53 AM EST	Areal Flood Warning	PHI	Chester	6 hr
Dec 25, 12:59 AM EST	River Flood Warning	PHI	Chester, Montgomery, Philadelphia	21 hr
Dec 25, 2:28 AM EST	River Flood Warning	PHI	Bucks	15 hr
Dec 25, 3:29 AM EST	Areal Flood Warning	PHI	Berks	6 hr
Dec 25, 3:33 AM EST	River Flood Warning	PHI	Chester, Delaware	17 hr
Dec 25, 4:00 AM EST	River Flood Warning	PHI	Lehigh, Northampton	16 hr
Dec 25, 4:31 AM EST	Areal Flood Warning	PHI	Carbon, Lehigh, Monroe, Northampton	7 hr
Dec 25, 4:53 AM EST	River Flood Warning	PHI	Berks, Montgomery	9 hr
Dec 25, 6:32 AM EST	River Flood Warning	PHI	Montgomery, Philadelphia	7 hr
Dec 25, 7:28 AM EST	River Flood Warning	PHI	Monroe	10 hr
Dec 25, 12:13 PM EST	Areal Flood Warning	PHI	Carbon, Monroe	9 hr
Dec 24, 10:52 PM EST	River Flood Warning	PHI	New Castle	7 hr
Dec 25, 12:08 AM EST	River Flood Warning	PHI	New Castle	7 hr
Dec 25, 1:28 AM EST	River Flood Warning	PHI	New Castle	8 hr

Nearby

Areal Flood Advisories in New Jersey, 2020 Every areal flood advisory in 2020

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.