Alert archive / Pennsylvania / Flood Watches in 2018

Flood Watch 4, NWS State College, PA

February 11, 20184 counties in Pennsylvania

NWS State College, PA issued this flood watch at Feb 11, 2018, 10:14 AM EST for 4 counties in Pennsylvania. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Feb 11, 2018, 10:14 AM EST (15:14 UTC)
Expired
Feb 11, 2018, 2:36 PM EST
In force
4 hr
Issued by
NWS State College, PA
Flood severity
None

Counties Adams County, PA, Lancaster County, PA, Lebanon County, PA, York County, PA

The radar

The Sterling radar (KLWX), 139 km from the middle of the area, began a volume at 15:13 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 3.2 hours before the alert went out and 138 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-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2018-02-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2018-02-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
503 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
87 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 11, 12:01 AM ESTDense Fog AdvisoryCTPAdams, Bedford, Blair, Cambria, Centre, Clearfield and 23 more10 hr
Feb 11, 6:40 PM ESTDense Fog AdvisoryCTPAdams, Columbia, Cumberland, Dauphin, Juniata, Lancaster and 9 more5 hr

Nearby

Flood Watches in Pennsylvania, 2018Every 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.