One last push of arctic air surged into Deep South Texas on February 19th and 20th as another strong arctic high settled in over the region. Though not as severe or prolonged as the earlier week freeze, this event still saw anomalously cold temperatures return to the region with the overwhelming majority of the area falling below freezing on both mornings of the 19th and 20th.
Unlike the prior events, conditions were drier in the low levels of the atmosphere, with mainly clear and breezy conditions on the 19th.  Winds diminished by sunset that day, setting the stage for a frosty freeze early on the 20th.

Frost/Freeze in BROOKS, TEXAS
From 18-FEB-21 22:30:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing across portions of Brooks County around 10:30 PM on the 18th and did not exceed 32 degrees again until 9:30 AM on the 19th. The Brooks County Airport recorded a low temperature of 25 degrees, while the La Rucia Mesonet site recorded a low of 26 degrees.

Frost/Freeze in COASTAL KENEDY COUNTY, TEXAS
From 19-FEB-21 04:00:00 to 19-FEB-21 09:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Despite sparse observation coverage, based off of observations from Inland Kenedy County and adjacent Kleberg County, it is estimated that temperatures fell below freezing across portions of Coastal Kenedy County around 4:00 AM and did not exceed 32 degrees again until 9:00 AM on the 19th. The nearby SARITA and ARMSTR Union Pacific Mesonet sites both recorded a low of 25 degrees.

Frost/Freeze in ZAPATA, TEXAS
From 20-FEB-21 05:30:00 to 20-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing around 5:30 AM on the 20th and did not rise back above 32 degrees until around 8:30 AM. A low of 27 degrees was recorded at the Zapata Airport.

Frost/Freeze in WILLACY, TEXAS
From 20-FEB-21 01:30:00 to 20-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 1:30 AM on the 20th and did not rise back above 32 degrees until around 8:30 AM. A low temperature of 27 degrees was recorded at the YTURIA Union Pacific Railroad Mesonet site.  Widespread frost joined the cold temperatures for most of the time when temperatures were below freezing.

Frost/Freeze in ZAPATA, TEXAS
From 19-FEB-21 01:30:00 to 19-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing around 1:30 AM on the 19th, and did not rise back above 32 degrees until around 8:30 AM. A low of 25 degrees was recorded at the Zapata Airport.

Frost/Freeze in STARR, TEXAS
From 19-FEB-21 04:00:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 4:00 AM on the 19th, and did not rise back above 32 degrees until around 9:30 AM. A low of 27 degrees was recorded at the Rancho Los Comitas Mesonet site, and a low of 28 degrees was recorded at the Falcon Lake RAWS site.

Frost/Freeze in WILLACY, TEXAS
From 19-FEB-21 03:30:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Due to data outages across the region, it is estimated that temperatures fell below freezing across portions of Willacy County around 3:30 AM on the 19th, and did not rise back above 32 degrees until around 9:30 AM. These times are estimated based off of nearby observations in adjacent portions of Cameron, Hidalgo, and Kenedy Counties. Lows in the lower 30s to upper 20s are estimated.

Frost/Freeze in INLAND KENEDY COUNTY, TEXAS
From 19-FEB-21 23:30:00 to 20-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 11:30 PM on the 19th and did not rise back above 32 degrees until around 9:30 AM on the 20th. A low temperature of 23 degrees was recorded at the SARITA Union Pacific Railroad Mesonet site, and a low of 29 degrees was recorded at the ARMSTR UPR site.  Widespread frost likely joined the freeze for the duration of the event.

Frost/Freeze in CAMERON, TEXAS
From 20-FEB-21 02:30:00 to 20-FEB-21 09:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 2:30 AM on the 20th and did not rise back above 32 degrees until around 9:00 AM. Lows fell into the lower 30s and upper 20s across the county. Widespread frost joined the cold temperatures, forming on roofs and vehicles under the clear skies prior to air temperatures falling below freezing, and as early as midnight; grass frost formed soon after.

Frost/Freeze in COASTAL WILLACY, TEXAS
From 20-FEB-21 02:00:00 to 20-FEB-21 08:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Despite sparse observation coverage in the area and based off of observations from Inland Willacy as well as other adjacent counties, it is estimated that temperatures fell below freezing around 2:00 AM on the 20th and did not rise back above 32 degrees until around 8:00 AM. A low temperature of 27 degrees was recorded at the nearby YTURIA Union Pacific Railroad Mesonet site.  Widespread frost likely joined the cold temperatures for nearly all of this event.

Frost/Freeze in SOUTHERN HIDALGO COUNTY, TEXAS
From 19-FEB-21 05:30:00 to 19-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Temperatures fell below freezing across northern portions of Southern Hidalgo County around 5:30 AM on the 19th, and did not rise back above 32 degrees until around 8:30 AM. A low of 28 degrees was recorded at Edinburg International Airport. The Mission CWOP site recorded a low of 30 degrees, and the Texas AgriScience TWDB site near Edcouch recorded a low of 31.

Frost/Freeze in NORTHERN HIDALGO COUNTY, TEXAS
From 19-FEB-21 05:30:00 to 19-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Temperatures fell below freezing around 5:30 AM on the 19th, and did not rise back above 32 degrees until around 8:30 AM. A low of 28 degrees was recorded at the San Manuel COOP site, and a low of 30 degrees was recorded at the Linn-San Manuel RAWS site.

Frost/Freeze in BROOKS, TEXAS
From 19-FEB-21 23:30:00 to 20-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing around 11:30 PM on the 19th and did not rise back above 32 degrees until around 9:30 AM on the 20th. A low temperature of 23 degrees was recorded at the Brooks County Airport.

Frost/Freeze in JIM HOGG, TEXAS
From 19-FEB-21 00:30:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing across portions of Jim Hogg County around 12:30 AM and did not exceed 32 degrees again until 9:30 AM on the 19th. The Hebbronville Airport recorded a low temperature of 25 degrees.

Frost/Freeze in COASTAL KENEDY COUNTY, TEXAS
From 19-FEB-21 04:00:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Based off of observations from Inland Kenedy and Coastal Kleberg Counties, temperatures fell below freezing across portions of Coastal Kenedy County around 4:00 AM and did not exceed 32 degrees again until 9:30 AM on the 19th. The nearby SARITA and ARMSTR Union Pacific Mesonet sites both recorded a low of 25 degrees, while some observations in Coastal Kleberg fell to 31 degrees.

Frost/Freeze in INLAND KENEDY COUNTY, TEXAS
From 19-FEB-21 03:30:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing across portions of Inland Kenedy County around 3:30 AM and did not exceed 32 degrees again until 9:30 AM on the 19th. The SARITA and ARMSTR Union Pacific Mesonet sites both recorded a low of 25 degrees.

Frost/Freeze in SOUTHERN HIDALGO COUNTY, TEXAS
From 20-FEB-21 03:30:00 to 20-FEB-21 07:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 3:30 AM on the 20th and did not rise back above 32 degrees until around 7:30 AM. Lows fell into the lower 30s and upper 20s across northern portions of Southern Hidalgo County.
Widespread frost joined the freezing temperatures for the entire event, likely beginning as early as midnight on vehicles, roofs, and grass.

Frost/Freeze in COASTAL CAMERON, TEXAS
From 20-FEB-21 03:30:00 to 20-FEB-21 07:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Temperatures fell below freezing across portions of Coastal Cameron County around 3:30 AM on the 20th and did not rise back above 32 degrees until around 7:30 AM. A low of 30 degrees was recorded at the Laguna Atascosa RAWS site.  Widespread frost joined the freezing temperatures, likely beginning as soon as midnight on vehicles and roofs, with grass frost soon after.

Frost/Freeze in STARR, TEXAS
From 19-FEB-21 23:30:00 to 20-FEB-21 07:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing around 11:30 PM on the 19th and did not rise back above 32 degrees until around 7:30 AM on the 20th. A low temperature of 25 degrees was recorded at the Ranco Los Comitas Mesonet site, and a low of 26 degrees was recorded at the Falcon Lake RAWS site.

Frost/Freeze in JIM HOGG, TEXAS
From 20-FEB-21 00:30:00 to 20-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Temperatures fell below freezing around 12:30 AM on the 20th and did not rise back above 32 degrees until around 8:30 AM. A low temperature of 28 degrees was recorded at the Hebbronville Airport.

Frost/Freeze in NORTHERN HIDALGO COUNTY, TEXAS
From 19-FEB-21 23:30:00 to 20-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Temperatures fell below freezing around 11:30 PM on the 19th and did not rise back above 32 degrees until around 8:30 AM on the 20th. A low temperature of 23 degrees was recorded at the Linn-San Manuel RAWS site, and a low of 28 degrees was recorded at the San Manuel COOP site.

Frost/Freeze in COASTAL WILLACY, TEXAS
From 19-FEB-21 04:00:00 to 19-FEB-21 09:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Despite sparse and intermittent observation coverage, it is estimated that temperatures fell below freezing across portions of Coastal Willacy County around 4:00 AM and did not exceed 32 degrees again until 9:30 AM on the 19th. It is estimated that low temperatures fell into the upper 20s and lower 30s across the area. This is estimated from observations in adjacent Kenedy and Cameron Counties, as well as Inland Willacy.

Frost/Freeze in CAMERON, TEXAS
From 19-FEB-21 04:30:00 to 19-FEB-21 09:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Temperatures fell below freezing across Cameron County around 4:30 AM and did not rise back above 32 degrees until around 9:00 AM on the 19th. Lows fell into the upper 20s and lower 30s across the area.

Frost/Freeze in COASTAL CAMERON, TEXAS
From 19-FEB-21 06:30:00 to 19-FEB-21 08:30:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Temperatures fell below freezing across Coastal Cameron County from around 6:30 AM to about 8:30 AM. The Laguna Atascosa RAWS site fell to 31 degrees while the Laguna Vista CWOP site fell to 32 degrees.