Alert archive / Pennsylvania / Areal Flood Warnings in 2024

Areal Flood Warning 36, NWS Philadelphia/Mount Holly

January 13, 2024Lehigh County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at Jan 13, 2024, 4:08 AM EST for Lehigh County, Montgomery 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 counties it named.

The facts

Issued: Jan 13, 2024, 4:08 AM EST (09:08 UTC)
Expired: Jan 13, 2024, 7:32 AM EST
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Lehigh County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 104 km from the middle of the area, began a volume at 09:11 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 9.1 hours before the alert went out and 276 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: 933 m above ground
0-6 km bulk shear: 81 kt
0-1 km storm-relative helicity: 619 m²/s²
0-3 km storm-relative helicity: 763 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 warning 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 warning went out at Jan 13, 1:35 AM EST, 2 hours 33 minutes earlier.

Area forecast discussion, Jan 13, 1:35 AM EST, 2 hours 33 minutes before

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Hazardous weather outlook, Jan 12, 10:44 PM EST, 5 hours 24 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
Jan 13, 6:45 AM EST	River Flood Warning	PHI	Passaic	15 hr
Jan 13, 7:52 AM EST	Marine Dense Fog Advisory	PHI		4 hr
Jan 13, 5:51 PM EST	Gale Warning	PHI		28 hr
Jan 13, 5:51 PM EST	Small Craft Advisory	PHI		10 hr

Nearby

Areal Flood Warnings in Pennsylvania, 2024 Every areal flood warning in 2024

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.