Alert archive / Indiana / Frost Advisories in 2021

Frost Advisory 7, NWS Louisville, KY

May 11, 20214 counties in Indiana

NWS Louisville, KY issued this frost advisory at May 11, 2021, 9:11 PM EDT for 4 counties in Indiana. It took effect at May 12, 2021, 3:00 AM EDT. It was in force for 118 min.

The area

The counties it named.

The facts

Issued
May 11, 2021, 9:11 PM EDT (01:11 UTC)
In effect from
May 12, 2021, 3:00 AM EDT
Expired
May 12, 2021, 4:58 AM EDT
In force
118 min
Issued by
NWS Louisville, KY

Counties Jefferson County, IN, Orange County, IN, Scott County, IN, Washington County, IN

The radar

The Louisville radar (KLVX), 75 km from the middle of the area, began a volume at 01:10 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 1.2 hours before the alert went out and 205 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 00:00Z on 2021-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2021-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 square meters per square second.1939587897117136156Sfc1 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
3 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
1769 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
-33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

597 
WWUS73 KLMK 120111
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
911 PM EDT Tue May 11 2021

...Frost Possible Toward Dawn On Wednesday...

The combination of clearing skies, slackening winds, and cool
low temperatures dipping into the 30s will allow for potential
frost formation in some areas toward dawn.

INZ076>079-120900-
/O.NEW.KLMK.FR.Y.0007.210512T0700Z-210512T1300Z/
Orange-Washington-Scott-Jefferson-
Including the cities of Paoli, Salem, Scottsburg, and Madison
911 PM EDT Tue May 11 2021

...FROST ADVISORY IN EFFECT FROM 3 AM TO 9 AM EDT WEDNESDAY...

The National Weather Service in Louisville has issued a Frost
Advisory, which is in effect from 3 AM to 9 AM EDT Wednesday. 

* TEMPERATURE...Upper 30s, with a few localized areas in the mid 
30s.

* IMPACTS...Frost could damage or kill sensitive outdoor
  vegetation if left unprotected.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Frost Advisory means that frost is expected. Sensitive outdoor 
plants may be killed if left uncovered.

&&

$$

BJS
2 follow-up statements
022 
WWUS73 KLMK 120428
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
1228 AM EDT Wed May 12 2021

INZ076>079-121300-
/O.CON.KLMK.FR.Y.0007.210512T0700Z-210512T1300Z/
Orange-Washington-Scott-Jefferson-
Including the cities of Paoli, Salem, Scottsburg, and Madison
1228 AM EDT Wed May 12 2021

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM EDT THIS MORNING...

* TEMPERATURE...Upper 30s, with a few localized areas in the mid 
  30s.

* IMPACTS...Frost could damage or kill sensitive outdoor 
  vegetation if left unprotected. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Sensitive outdoor plants may be killed if left uncovered.

&&

$$
944 
WWUS73 KLMK 120858
NPWLMK

URGENT - WEATHER MESSAGE
National Weather Service Louisville KY
458 AM EDT Wed May 12 2021

INZ076>079-121000-
/O.CAN.KLMK.FR.Y.0007.000000T0000Z-210512T1300Z/
Orange-Washington-Scott-Jefferson-
Including the cities of Paoli, Salem, Scottsburg, and Madison
458 AM EDT Wed May 12 2021

...FROST ADVISORY IS CANCELLED...

The National Weather Service in Louisville has cancelled the
Frost Advisory. 

Light northeasterly winds and temperatures falling into the low 
40s should prevent frost from developing this morning. As a 
result, the frost advisory has been cancelled early. 

$$

Nearby

Frost 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.