Alert archive / Kentucky / Frost Advisories in 2021

Frost Advisory 6, NWS Louisville, KY

May 7, 20218 counties in Kentucky; Jefferson County, Indiana

NWS Louisville, KY issued this frost advisory at May 7, 2021, 2:41 PM EDT for 8 counties in Kentucky; Jefferson County, Indiana. It took effect at May 8, 2021, 3:00 AM EDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
May 7, 2021, 2:41 PM EDT (18:41 UTC)
In effect from
May 8, 2021, 3:00 AM EDT
Expired
May 8, 2021, 8:00 AM EDT
In force
5 hr
Issued by
NWS Louisville, KY

Counties Jefferson County, IN, Bourbon County, KY, Clark County, KY, Franklin County, KY, Harrison County, KY, Henry County, KY, Nicholas County, KY, Scott County, KY, Trimble County, KY

The radar

The Louisville radar (KLVX), 119 km from the middle of the area, began a volume at 18:46 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 6.7 hours before the alert went out and 140 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, Cncnati-Daytn, OH at 12:00Z on 2021-05-07Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 12:00Z on 2021-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -44 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
744 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-44 m²/s²
0-3 km storm-relative helicity
-39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

171 
WWUS73 KLMK 071841
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
241 PM EDT Fri May 7 2021

INZ079-KYZ032-033-035>037-042-043-049-080900-
/O.NEW.KLMK.FR.Y.0006.210508T0700Z-210508T1400Z/
Jefferson-Trimble-Henry-Franklin-Scott-Harrison-Bourbon-Nicholas-
Clark-
Including the cities of Madison, Bedford, Milton, New Castle, 
Frankfort, Georgetown, Cynthiana, Paris, Carlisle, and Winchester
241 PM EDT Fri May 7 2021

...FROST ADVISORY IN EFFECT FROM 3 AM TO 10 AM EDT SATURDAY...

The National Weather Service in Louisville has issued a Frost
Advisory, which is in effect from 3 AM to 10 AM EDT Saturday. 

* TEMPERATURE...lows will briefly dip into the mid and upper 30s
  for a few hours around sunrise.

* IMPACTS...Vegetation sensitive to frost may be damaged or 
  killed if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Frost Advisory means that widespread frost is expected.

&&

$$

13
2 follow-up statements
837 
WWUS73 KLMK 080624
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
224 AM EDT Sat May 8 2021

INZ079-KYZ032-033-035>037-042-043-049-081200-
/O.EXT.KLMK.FR.Y.0006.210508T0700Z-210508T1200Z/
Jefferson-Trimble-Henry-Franklin-Scott-Harrison-Bourbon-Nicholas-
Clark-
Including the cities of Madison, Bedford, Milton, New Castle, 
Frankfort, Georgetown, Cynthiana, Paris, Carlisle, and Winchester
224 AM EDT Sat May 8 2021

...FROST ADVISORY NOW IN EFFECT UNTIL 8 AM EDT THIS MORNING...

* TEMPERATURE...Lows will briefly dip into the upper 30s for a 
  few hours around sunrise. 

* IMPACTS...Vegetation sensitive to frost may be damaged or 
  killed if left uncovered. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Sensitive outdoor plants may be killed if left uncovered.

&&

$$
498 
WWUS73 KLMK 081217
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
817 AM EDT Sat May 8 2021


INZ079-KYZ032-033-035>037-042-043-049-081330-
/O.EXP.KLMK.FR.Y.0006.000000T0000Z-210508T1200Z/
Jefferson-Trimble-Henry-Franklin-Scott-Harrison-Bourbon-Nicholas-
Clark-
Including the cities of Madison, Bedford, Milton, New Castle, 
Frankfort, Georgetown, Cynthiana, Paris, Carlisle, and Winchester
817 AM EDT Sat May 8 2021

...FROST ADVISORY HAS EXPIRED...

Temperatures in the advisory area are warming into the 40s, and
the potential for frost has ended.

$$

RAS

Nearby

Frost Advisories in Kentucky, 2021Frost Advisories in Indiana, 2021Every frost advisory in 2021

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.