Alert archive / Pennsylvania / Flash Flood Watches in 2018

Flash Flood Watch 7, NWS State College, PA

July 4, 201820 counties in Pennsylvania

NWS State College, PA issued this flash flood watch at Jul 4, 2018, 9:54 AM EDT for 20 counties in Pennsylvania. It was in force for 10 hr.

The area

The counties it named.

The facts

Issued: Jul 4, 2018, 9:54 AM EDT (13:54 UTC)
Expired: Jul 4, 2018, 8:05 PM EDT
In force: 10 hr
Issued by: NWS State College, PA
Flood severity: None

Counties Blair County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Elk County, PA, Huntingdon County, PA, Lycoming County, PA, McKean County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Potter County, PA, Snyder County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA, Warren County, PA

The radar

The State College radar (KCCX), 35 km from the middle of the area, began a volume at 13:54 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

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 1.9 hours before the alert went out and 217 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: 466 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 1219 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 8 m²/s²
0-3 km storm-relative helicity: 26 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 flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before this flash flood watch went out at Jul 4, 7:37 AM EDT, 2 hours 17 minutes earlier.

Area forecast discussion, Jul 4, 7:37 AM EDT, 2 hours 17 minutes before

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Hazardous weather outlook, Jul 4, 3:15 AM EDT, 6 hours 39 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 3, 8:12 PM EDT	Special Weather Statement	CTP	Lancaster	33 min
Jul 3, 8:58 PM EDT	Special Weather Statement	CTP	Lancaster	17 min
Jul 3, 9:05 PM EDT	Areal Flood Advisory	CTP	Lancaster, York	3 hr
Jul 3, 11:17 PM EDT	Special Weather Statement	CTP	Elk	13 min
Jul 4, 7:35 AM EDT	Areal Flood Advisory	CTP	Sullivan	3 hr
Jul 4, 9:03 AM EDT	Areal Flood Advisory	CTP	Potter, Tioga	117 min
Jul 4, 10:18 AM EDT	Areal Flood Advisory	CTP	McKean	117 min
Jul 4, 10:29 AM EDT	Areal Flood Advisory	CTP	Potter, Tioga	2 hr
Jul 4, 11:53 AM EDT	Special Weather Statement	CTP	Sullivan	52 min
Jul 4, 12:21 PM EDT	Flash Flood Warning	CTP	Potter, Tioga	3 hr
Jul 4, 12:31 PM EDT	Flash Flood Warning	CTP	Sullivan	3 hr
Jul 4, 12:51 PM EDT	Special Weather Statement	CTP	Cameron	24 min
Jul 4, 1:08 PM EDT	Areal Flood Advisory	CTP	Columbia	112 min
Jul 4, 1:23 PM EDT	Areal Flood Advisory	CTP	Centre, Clearfield	3 hr
Jul 4, 1:28 PM EDT	Flash Flood Warning	CTP	Columbia	3 hr
Jul 4, 1:58 PM EDT	Special Weather Statement	CTP	Union	32 min
Jul 4, 2:00 PM EDT	Special Weather Statement	CTP	Mifflin	45 min
Jul 4, 2:19 PM EDT	Heat Advisory	CTP	Adams, Cumberland, Dauphin, Lancaster, Lebanon, Perry and 2 more	4 hr
Jul 4, 2:30 PM EDT	Special Weather Statement	CTP	Montour	30 min
Jul 4, 2:35 PM EDT	Special Weather Statement	CTP	Mifflin	40 min
Jul 4, 2:51 PM EDT	Special Weather Statement	CTP	Franklin	24 min
Jul 4, 2:53 PM EDT	Special Weather Statement	CTP	Cambria	37 min
Jul 4, 3:10 PM EDT	Severe Thunderstorm Warning	CTP	Franklin	39 min
Jul 4, 3:27 PM EDT	Special Weather Statement	CTP	Fulton	33 min
Jul 4, 3:31 PM EDT	Flash Flood Warning	CTP	Sullivan	3 hr
Jul 4, 3:59 PM EDT	Areal Flood Advisory	CTP	Cambria	2 hr
Jul 4, 4:05 PM EDT	Special Weather Statement	CTP	Adams	25 min
Jul 4, 4:09 PM EDT	Special Weather Statement	CTP	Lebanon	36 min
Jul 4, 4:16 PM EDT	Areal Flood Advisory	CTP	Adams	3 hr
Jul 4, 4:40 PM EDT	Areal Flood Advisory	CTP	Adams, Cumberland, Dauphin, Lancaster, Lebanon, Perry and 2 more	3 hr
Jul 4, 7:50 PM EDT	Areal Flood Advisory	CTP	Adams, Cumberland, Dauphin, Lancaster, Lebanon, Perry and 2 more	3 hr

Nearby

Flash Flood Watches in Pennsylvania, 2018 Every flash flood watch in 2018

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.