Alert archive / North Carolina / Freeze Warnings in 2020

Freeze Warning 1, NWS Raleigh, NC

April 10, 202017 counties in North Carolina

NWS Raleigh, NC issued this freeze warning at Apr 10, 2020, 3:13 PM EDT for 17 counties in North Carolina. It took effect at Apr 11, 2020, 3:00 AM EDT. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 10, 2020, 3:13 PM EDT (19:13 UTC)
In effect from: Apr 11, 2020, 3:00 AM EDT
Expired: Apr 11, 2020, 8:18 AM EDT
In force: 5 hr
Issued by: NWS Raleigh, NC

Counties Alamance County, NC, Anson County, NC, Chatham County, NC, Davidson County, NC, Durham County, NC, Forsyth County, NC, Granville County, NC, Guilford County, NC, Lee County, NC, Montgomery County, NC, Moore County, NC, Orange County, NC, Person County, NC, Randolph County, NC, Richmond County, NC, Stanly County, NC, Vance County, NC

The radar

The Raleigh/Durham radar (KRAX), 91 km from the middle of the area, began a volume at 19:10 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 12:00Z, 7.2 hours before the alert went out and 50 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1628 m above ground
0-6 km bulk shear: 121 kt
0-1 km storm-relative helicity: -158 m²/s²
0-3 km storm-relative helicity: -68 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this freeze warning 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 freeze warning went out at Apr 10, 3:10 PM EDT, 3 minutes earlier.

Area forecast discussion, Apr 10, 3:10 PM EDT, 3 minutes before

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Hazardous weather outlook, Apr 10, 10:51 AM EDT, 4 hours 22 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
Apr 10, 10:49 AM EDT	Red Flag Warning	RAH	Alamance, Anson, Chatham, Cumberland, Davidson, Durham and 25 more	7 hr
Apr 10, 3:13 PM EDT	Frost Advisory	RAH	Anson, Chatham, Cumberland, Davidson, Edgecombe, Franklin and 17 more	17 hr

Nearby

Freeze Warnings in North Carolina, 2020 Every freeze warning in 2020

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.