Alert archive / Pennsylvania / Flash Flood Watches in 2018

Flash Flood Watch 17, NWS State College, PA

October 2, 201813 counties in Pennsylvania

NWS State College, PA issued this flash flood watch at Oct 2, 2018, 1:12 PM EDT for 13 counties in Pennsylvania. It took effect at Oct 2, 2018, 2:00 PM EDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued: Oct 2, 2018, 1:12 PM EDT (17:12 UTC)
In effect from: Oct 2, 2018, 2:00 PM EDT
Expired: Oct 2, 2018, 9:45 PM EDT
In force: 8 hr
Issued by: NWS State College, PA
Flood severity: None

Counties Centre County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Lycoming County, PA, McKean County, PA, Montour County, PA, Northumberland County, PA, Potter County, PA, Snyder County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA

The radar

The State College radar (KCCX), 67 km from the middle of the area, began a volume at 17:14 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, 5.2 hours before the alert went out and 221 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: 13 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 476 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 205 m²/s²
0-3 km storm-relative helicity: 232 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 Oct 2, 11:35 AM EDT, 1 hour 37 minutes earlier.

Area forecast discussion, Oct 2, 11:35 AM EDT, 1 hour 37 minutes before

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Hazardous weather outlook, Oct 2, 10:59 AM EDT, 2 hours 13 minutes before

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In the hours before

Special weather statement, Oct 2, 11:07 AM EDT, 2 hours 5 minutes before

Special Weather Statement
National Weather Service State College PA
1107 AM EDT TUE OCT 2 2018

PAZ004-005-021545-
McKean PA-Warren PA-
1107 AM EDT TUE OCT 2 2018

...STRONG THUNDERSTORMS WILL AFFECT PARTS OF WARREN AND MCKEAN
COUNTIES UNTIL 1145 AM EDT...

At 1106 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from near Bradford to near Chapman State Park.
Movement was east at 40 mph.

Winds in excess of 40 mph are possible.

Locations impacted include...
Warren, Bradford, Port Allegany, Sheffield, Smethport, Shinglehouse,
Rew, Coryville, Crosby, Cyclone, Ludlow, Marshburg, Westline, Kinzua
Bridge State Park, Kinzua Dam, Chapman State Park, Warren South,
Mount Jewett, Eldred and Lewis Run.

LAT...LON 4185 7821 4170 7839 4171 7939 4200 7882
      4200 7820
TIME...MOT...LOC 1506Z 269DEG 34KT 4198 7860 4174 7920

RXR

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 2, 11:07 AM EDT	Special Weather Statement	CTP	McKean	38 min
Oct 2, 1:20 PM EDT	Areal Flood Advisory	CTP	Potter	3 hr
Oct 2, 1:59 PM EDT	Special Weather Statement	CTP	Tioga	61 min
Oct 2, 2:48 PM EDT	Special Weather Statement	CTP	Tioga	42 min
Oct 2, 3:03 PM EDT	Severe Thunderstorm Warning	CTP	Tioga	42 min
Oct 2, 3:11 PM EDT	Severe Thunderstorm Warning	CTP	Warren	79 min
Oct 2, 3:24 PM EDT	Severe Thunderstorm Warning	CTP	Potter, Tioga	96 min
Oct 2, 3:27 PM EDT	Special Weather Statement	CTP	Lycoming	33 min
Oct 2, 3:38 PM EDT	Tornado Warning	CTP	Warren	67 min
Oct 2, 3:48 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Lycoming, Montour, Northumberland, Sullivan	57 min
Oct 2, 3:51 PM EDT	Tornado Warning	CTP	Columbia, Lycoming, Montour, Northumberland	54 min
Oct 2, 3:59 PM EDT	Areal Flood Advisory	CTP	Potter, Tioga	3 hr
Oct 2, 4:05 PM EDT	Special Weather Statement	CTP	McKean	55 min
Oct 2, 4:06 PM EDT	Areal Flood Advisory	CTP	Warren	3 hr
Oct 2, 4:15 PM EDT	Tornado Warning	CTP	Potter, Tioga	45 min
Oct 2, 4:19 PM EDT	Severe Thunderstorm Warning	CTP	Franklin, Huntingdon	56 min
Oct 2, 4:26 PM EDT	Severe Thunderstorm Warning	CTP	Cameron, Clearfield, Elk	64 min
Oct 2, 4:26 PM EDT	Severe Thunderstorm Warning	CTP	Elk	49 min
Oct 2, 4:26 PM EDT	Tornado Warning	CTP	Columbia, Lycoming, Montour	49 min
Oct 2, 4:42 PM EDT	Tornado Warning	CTP	Clearfield	63 min
Oct 2, 4:48 PM EDT	Tornado Warning Tornado observed	CTP	Lycoming, Tioga	42 min
Oct 2, 4:49 PM EDT	Special Weather Statement	CTP	Sullivan	26 min
Oct 2, 4:54 PM EDT	Special Weather Statement	CTP	Tioga	36 min
Oct 2, 5:02 PM EDT	Tornado Warning	CTP	Clearfield, Elk	43 min
Oct 2, 5:17 PM EDT	Severe Thunderstorm Warning	CTP	Cumberland	58 min
Oct 2, 5:24 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Tioga	36 min
Oct 2, 5:27 PM EDT	Severe Thunderstorm Warning	CTP	Cameron, Centre, Clearfield, Clinton, Elk, Potter	93 min
Oct 2, 5:28 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan	34 min
Oct 2, 5:32 PM EDT	Tornado Warning	CTP	Clearfield	58 min
Oct 2, 5:33 PM EDT	Tornado Warning	CTP	Lycoming, Tioga	42 min
Oct 2, 5:39 PM EDT	Tornado Warning	CTP	Lycoming, Sullivan	66 min
Oct 2, 5:56 PM EDT	Areal Flood Advisory	CTP	Lycoming, Tioga	3 hr
Oct 2, 6:06 PM EDT	Severe Thunderstorm Warning	CTP	Somerset	32 min
Oct 2, 6:19 PM EDT	Areal Flood Advisory	CTP	Clearfield, Elk	3 hr
Oct 2, 6:25 PM EDT	Areal Flood Advisory	CTP	Lycoming, Sullivan	3 hr
Oct 2, 6:37 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clinton, Union	53 min
Oct 2, 6:39 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Sullivan	21 min
Oct 2, 7:00 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clearfield	90 min
Oct 2, 7:13 PM EDT	Areal Flood Advisory	CTP	Cameron, Centre, Clinton	3 hr
Oct 2, 7:44 PM EDT	Special Weather Statement	CTP	Northumberland	31 min
Oct 2, 7:53 PM EDT	Flash Flood Warning	CTP	Columbia, Lycoming, Sullivan	3 hr
Oct 2, 7:57 PM EDT	Special Weather Statement	CTP	Snyder	33 min
Oct 2, 7:59 PM EDT	Flash Flood Warning	CTP	Centre, Clearfield	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.