Alert archive / North Carolina / Flash Flood Watches in 2018

Flash Flood Watch 5, NWS Raleigh, NC

July 31, 20185 counties in North Carolina

NWS Raleigh, NC issued this flash flood watch at Jul 31, 2018, 3:59 AM EDT for 5 counties in North Carolina. It took effect at Jul 31, 2018, 12:00 PM EDT. It was in force for 16 hr.

The area

The counties it named.

The facts

Issued: Jul 31, 2018, 3:59 AM EDT (07:59 UTC)
In effect from: Jul 31, 2018, 12:00 PM EDT
Expired: Aug 1, 2018, 3:46 AM EDT
In force: 16 hr
Issued by: NWS Raleigh, NC
Flood severity: None

Counties Davidson County, NC, Forsyth County, NC, Guilford County, NC, Randolph County, NC, Stanly County, NC

The radar

The Roanoke radar (KFCX), 137 km from the middle of the area, began a volume at 08:02 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, 8.0 hours before the alert went out and 34 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: 1556 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 825 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: 18 m²/s²
Significant tornado parameter: -0.1
Supercell composite: -1.2

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 Raleigh, NC wrote its last area forecast discussion before this flash flood watch went out at Jul 31, 3:35 AM EDT, 24 minutes earlier.

Area forecast discussion, Jul 31, 3:35 AM EDT, 24 minutes before

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Hazardous weather outlook, Jul 30, 6:44 PM EDT, 9 hours 15 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 2:41 PM EDT	Areal Flood Advisory	RAH	Chatham, Durham, Orange	93 min
Jul 31, 4:11 PM EDT	Special Weather Statement	RAH	Forsyth	34 min
Jul 31, 4:19 PM EDT	Special Weather Statement	RAH	Davidson	41 min
Jul 31, 4:47 PM EDT	Special Weather Statement	RAH	Forsyth	58 min
Jul 31, 5:39 PM EDT	Special Weather Statement	RAH	Forsyth	36 min
Jul 31, 5:58 PM EDT	Areal Flood Advisory	RAH	Halifax	3 hr
Jul 31, 7:06 PM EDT	Areal Flood Advisory	RAH	Edgecombe, Nash, Wilson	6 hr
Jul 31, 7:19 PM EDT	Special Weather Statement	RAH	Harnett	26 min
Jul 31, 7:24 PM EDT	Special Weather Statement	RAH	Edgecombe	66 min
Jul 31, 7:27 PM EDT	Severe Thunderstorm Warning	RAH	Edgecombe, Nash, Wilson	63 min

Nearby

Flash Flood Watches in North Carolina, 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.