Alert archive / Pennsylvania / Flash Flood Watches in 2017

Flash Flood Watch 5, NWS Pittsburgh, PA

June 30, 2017Lawrence County, Mercer County, Venango County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood watch at Jun 30, 2017, 5:33 PM EDT for Lawrence County, Mercer County, Venango County, Pennsylvania. It took effect at Jun 30, 2017, 6:00 PM EDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued: Jun 30, 2017, 5:33 PM EDT (21:33 UTC)
In effect from: Jun 30, 2017, 6:00 PM EDT
Expired: Jul 1, 2017, 3:27 AM EDT
In force: 9 hr
Issued by: NWS Pittsburgh, PA
Flood severity: None

Counties Lawrence County, PA, Mercer County, PA, Venango County, PA

The radar

The Pittsburgh radar (KPBZ), 78 km from the middle of the area, began a volume at 21:32 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

Pittsburgh, PA (KAGC), launched 12:00Z, 9.6 hours before the alert went out and 91 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: 260 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 879 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 152 m²/s²
0-3 km storm-relative helicity: 132 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Pittsburgh, PA wrote its last area forecast discussion before this flash flood watch went out at Jun 30, 1:42 PM EDT, 3 hours 51 minutes earlier.

Area forecast discussion, Jun 30, 1:42 PM EDT, 3 hours 51 minutes before

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Hazardous weather outlook, Jun 30, 3:24 AM EDT, 14 hours 9 minutes before

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In the hours before

Special weather statement, Jun 30, 3:05 PM EDT, 2 hours 28 minutes before

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Special weather statement, Jun 30, 3:17 PM EDT, 2 hours 16 minutes before

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The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 29, 9:16 PM EDT	Severe Thunderstorm Warning	PBZ	Mercer, Venango	44 min
Jun 29, 9:19 PM EDT	Severe Thunderstorm Warning	PBZ	Butler, Lawrence, Mercer	41 min
Jun 29, 9:56 PM EDT	Severe Thunderstorm Warning	PBZ	Butler, Lawrence, Mercer	49 min
Jun 29, 10:01 PM EDT	Severe Thunderstorm Warning	PBZ	Butler, Clarion, Mercer, Venango	44 min
Jun 29, 10:35 PM EDT	Severe Thunderstorm Warning	PBZ	Beaver	40 min
Jun 29, 11:08 PM EDT	Special Weather Statement	PBZ	Allegheny	52 min
Jun 30, 3:05 PM EDT	Special Weather Statement	PBZ	Indiana	25 min
Jun 30, 3:17 PM EDT	Special Weather Statement	PBZ	Allegheny	28 min
Jun 30, 7:34 PM EDT	Special Weather Statement	PBZ	Lawrence	26 min
Jun 29, 9:47 PM EDT	Severe Thunderstorm Warning	PBZ	Carroll, Columbiana	43 min
Jun 29, 10:15 PM EDT	Special Weather Statement	PBZ	Carroll, Coshocton, Tuscarawas	30 min
Jun 29, 10:31 PM EDT	Severe Thunderstorm Warning	PBZ	Carroll, Columbiana, Jefferson, Tuscarawas	44 min
Jun 30, 6:35 PM EDT	Special Weather Statement	PBZ	Carroll	25 min
Jun 30, 7:25 PM EDT	Special Weather Statement	PBZ	Mahoning	35 min
Jun 29, 11:13 PM EDT	Special Weather Statement	PBZ	Hancock	47 min

Nearby

Flash Flood Watches in Pennsylvania, 2017 Every flash flood watch in 2017

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.