Alert archive / North Carolina / Flash Flood Warnings in 2016

Flash Flood Warning 18, NWS Raleigh, NC

July 31, 2016Orange County, North Carolina

NWS Raleigh, NC issued this flash flood warning at Jul 31, 2016, 8:09 PM EDT for Orange County, North Carolina. It was in force for 96 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 31, 2016, 8:09 PM EDT (00:09 UTC)
Expired: Jul 31, 2016, 9:45 PM EDT
In force: 96 min
Issued by: NWS Raleigh, NC
Area: Storm-based polygon
Flood severity: None

County Orange County, NC

The radar

The Raleigh/Durham radar (KRAX), 80 km from the middle of the area, began a volume at 00:12 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

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 0.2 hours before the alert went out and 70 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: 537 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 1704 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 64 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

605 
WGUS52 KRAH 010009
FFWRAH
NCC135-010145-
/O.NEW.KRAH.FF.W.0018.160801T0009Z-160801T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
809 PM EDT SUN JUL 31 2016

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN ORANGE COUNTY IN CENTRAL NORTH CAROLINA...

* UNTIL 945 PM EDT
  
* AT 809 PM EDT...DOPPLER RADAR INDICATED A THUNDERSTORM PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. UP TO THREE INCHES OF RAIN HAVE
  ALREADY FALLEN. FLASH FLOODING IS EXPECTED TO BEGIN SHORTLY.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  HILLSBOROUGH...CARR...SCHLEY AND EFLAND. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXTREMELY DANGEROUS. NUMEROUS ROADS AND LOW LYING
AREAS WILL QUICKLY FLOOD. FLOOD WATERS WILL ALSO THREATEN SOME HOMES
AND BUSINESSES. IF YOU ARE EXPERIENCING FLOODING OR LIVE IN A FLOOD
PRONE AREA...MOVE TO HIGHER GROUND.

&&

LAT...LON 3624 7902 3606 7911 3606 7925 3623 7925

$$

GIH

1 follow-up statement

889 
WGUS72 KRAH 010122
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
922 PM EDT SUN JUL 31 2016

NCC135-010132-
/O.CAN.KRAH.FF.W.0018.000000T0000Z-160801T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ORANGE NC-
922 PM EDT SUN JUL 31 2016

...THE FLASH FLOOD WARNING FOR NORTHWESTERN ORANGE COUNTY IS
CANCELLED...

THE HEAVY RAIN HAS ENDED ACROSS THE WARNED AREA... AND FLOODING IS
NO LONGER EXPECTED TO POSE A THREAT. PLEASE CONTINUE TO HEED ANY
REMAINING ROAD CLOSURES.

LAT...LON 3624 7902 3606 7911 3606 7925 3623 7925

$$

GIH

The office that day

Everything else NWS Raleigh, NC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 31, 8:04 PM EDT	Severe Thunderstorm Warning	RAH	Alamance, Chatham, Durham, Orange	41 min
Jul 31, 8:26 PM EDT	Severe Thunderstorm Warning	RAH	Davidson, Randolph	49 min
Jul 31, 8:43 PM EDT	Areal Flood Advisory	RAH	Davidson, Randolph	2 hr
Jul 31, 8:46 PM EDT	Special Weather Statement	RAH	Chatham, Durham, Wake	74 min
Jul 31, 9:14 PM EDT	Areal Flood Advisory	RAH	Alamance, Chatham, Durham, Orange	2 hr
Jul 31, 9:25 PM EDT	Flash Flood Warning	RAH	Davidson	5 hr
Jul 31, 9:27 PM EDT	Severe Thunderstorm Warning	RAH	Chatham, Durham, Harnett, Johnston, Lee, Wake	36 min
Aug 1, 12:18 AM EDT	Areal Flood Advisory	RAH	Davidson, Guilford, Randolph	3 hr
Aug 1, 2:18 AM EDT	Areal Flood Advisory	RAH	Davidson, Randolph	3 hr
Aug 1, 4:19 PM EDT	Special Weather Statement	RAH	Sampson	41 min
Aug 1, 4:24 PM EDT	Special Weather Statement	RAH	Richmond	36 min
Aug 1, 5:40 PM EDT	Special Weather Statement	RAH	Wayne	65 min

Nearby

Flash Flood Warnings in North Carolina, 2016 Every flash flood warning in 2016

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.