Alert archive / Pennsylvania / Flash Flood Watches in 2018

Flash Flood Watch 3, NWS State College, PA

May 27, 20188 counties in Pennsylvania

NWS State College, PA issued this flash flood watch at May 27, 2018, 1:14 PM EDT for 8 counties in Pennsylvania. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
May 27, 2018, 1:14 PM EDT (17:14 UTC)
Expired
May 27, 2018, 8:40 PM EDT
In force
7 hr
Issued by
NWS State College, PA
Flood severity
None

Counties Adams County, PA, Bedford County, PA, Cumberland County, PA, Franklin County, PA, Fulton County, PA, Lancaster County, PA, Somerset County, PA, York County, PA

The radar

The State College radar (KCCX), 110 km from the middle of the area, began a volume at 17:13 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, 5.2 hours before the alert went out and 116 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 2018-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 51 joules per kilogram.LCLLFCEL10008507005003002001001 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 2018-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -25 square meters per square second.1939Sfc1 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
51 J/kg
Mixed-layer CIN
-95 J/kg
Mixed-layer LCL
925 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.4

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 2:11 PM EDTAreal Flood AdvisoryCTPBedford3 hr
May 27, 2:43 PM EDTSpecial Weather StatementCTPAdams32 min
May 27, 2:52 PM EDTSpecial Weather StatementCTPYork23 min
May 27, 3:19 PM EDTSpecial Weather StatementCTPYork41 min

Nearby

Flash Flood Watches in Pennsylvania, 2018Every 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.