Cold and Frost and Freeze in Texas, February 19 to 22, 2025

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
527 PM CST Wed Feb 19 2025

...New AVIATION...

.SHORT TERM...
(Tonight through Thursday night)
Issued at 346 PM CST Wed Feb 19 2025

Key Messages:

* Cold Weather Settling in through Thursday Night with sub-
  freezing feels like temperatures through mid morning Thursday

* Ranchlands freeze early Friday with some issues for the RGV
  growing areas due to cold air and lower humidity

* Continued difficult to dangerous boating conditions on the Gulf
  and Laguna Madre tonight...and on the Gulf through Thursday
  night

The big picture of the inherited forecast is right on track...so
minimal changes were made for this update. The modified arctic air
indeed arrived as expected and the colder model solutions won the
day...no surprise given the source region of the air mass from
northwest Canada north of the Arctic Circle. With that in mind,
the main modifications to the forecast were made for locations
toward the coast, where northwest flow drives the shallow cold air
to and even just beyond the shoreline, and given the density of
the air and lack of future forcing to erode it, have maintained
these trends into early Friday.

So...given the fact that the cold air...upper 30s ambient
temperatures...reached the coast this afternoon while
north/northwest winds continue at 20+ mph...have extended in
area/time the Cold Weather Advisory for wind chills at or below 30
along the lower Texas coast and flirting with 25 along Padre
Island National Seashore (PINS) in Kenedy to begin this afternoon
and continue into the original advisory that begins at midnight.
That advisory is well in hand, as actual temperatures will dip
into the 30s in all areas around or just after midnight while
winds persist in the 10-15 mph range over inland areas.

The freeze warning area looks right in line as well, with just a
nudge down a degree to match model blends and some thinning of
clouds...as well as the gradual drop in dewpoints (now into the
mid 20s as we write) into the upper teens or so overnight. Did
nudge temperatures to the freezing point in
Hidalgo/Willacy/northern Starr/northwest Cameron. No warning based
on temperature criteria. However...and this is important...the
expectation of wet bulb temperatures (which help determine
saturation temperature) into the mid to upper 20s may well be an
issue for the rapid early-season blooms on citrus and other spring
crops (mainly vegetables) courtesy of the record February 1-12
warmth and humidity. We'll continue to message this aspect as a
concern.

For Thursday, the slate-gray sky across the lower/mid Valley will
block out insolation, and temperatures will rebound but only into
the lower 40s. Mid to upper 40s are more likely across the Rio
Grande Plains/upper Valley where higher ceilings are more likely.
The coast? Model blends far overcooked with recovery of
temperatures and with northwest flow continuing, expect only a
rise into the low/mid 40s there as well.

The developing coastal trough (well offshore in the temperature
gradient) Thursday night will signal the onset of sprinkles, then
areas of drizzle, nosing from east to west with perhaps some
light wetting rain close to the coast. Ceilings will lower but
northwest winds continue, and temperatures will drop toward their
wet bulb values which means 30s for most by early Friday. No
freeze at this point but may be close across the Brush Country.

The persistence of the cold over Laguna Madre Bay will create
another minor sea turtle stun event, to begin as early as midday
Thursday and peak on Friday, and perhaps into Saturday as well.

Those cold surf temperatures will be more reason for people to
stay out of the surf which will be filled with high waves and
dangerous rip/northerly longshore currents.

&&

.LONG TERM...
(Friday through next Wednesday)
Issued at 346 PM CST Wed Feb 19 2025

Key Messages:

* Continued raw with miserable rain Friday into at least early
  Saturday, with sea turtle stunning likely along the coast

* Welcome but gradual warmup begins Sunday and peaks Tuesday and
  Wednesday

Isentropic upglide over the shallow Arctic airmass, with moisture
advection brought about by surface troughing along the lower to
middle Texas coast will continue chances of rain early in the long
term. Rain chances are greatest Friday morning, with a moderate to
high chance (50-80%) east of I-69C, and 30-50% for the remainder of
the CWA. PoPs gradually decrease through Saturday, decreasing from
west to east.

Northwesterly flow, along with precipitation and increased cloud
cover will keep temperatures suppressed to below normal. Below
average temperatures (highs and lows) are expected through Sunday
night, although gradually increasing closer to normal through the
weekend.

By Sunday, a 500hPa trough will swing through Texas, eroding the
Arctic airmass settled over east-central CONUS. This will evacuate
moisture being advected in from the coastal troughing, decreasing
PoPs to near zero and allowing sunlight to peek through for early
next week. How fast this moisture is advected out, and how early
clouds lift will greatly influence high temperatures on Sunday. More
dry air advection earlier in the day can allow for greater solar
insolation and subsequently an increase in temperatures. Western
counties (Zapata, Starr) are most likely to experience warming on
Sunday. By Monday, the dry airmass in place and southerly flow will
gradually increase temperatures and by Tuesday, high temperatures
are expected to return to above-normal.

&&

.AVIATION...
(00Z TAFS)
Issued at 525 PM CST Wed Feb 19 2025

Through 00z Friday....A BKN-OVC deck of low VFR to MVFR cigs will by
and large remain in place through the 00z TAF period, following the
passage of the Arctic cold front.

Breezy northerly winds will remain in place through the period.
North winds 10-20 kts gusting up to 25 kts or so will subside
slightly this evening. However, gusts will still remain elevated
in the 15-20 kt range through the remainder of the forecast
period.

&&

.MARINE...
Issued at 346 PM CST Wed Feb 19 2025

3 PM Wednesday through Thursday Night:
Gale conditions have fallen off as expected across all waters, but
still some periodic gusts to near 30 knots with seas over 11 feet
making for nearly impossible conditions for small craft and
difficulty for shippers as well this afternoon. No rest for the
weary into Thursday or even Thursday night...though Laguna
conditions will improve a bit but still a stiff northwest breeze
and choppy conditions much of the time.

Friday through Monday Night...Marine conditions will remain
generally unfavorable through Sunday. Moderate seas with a
moderate to fresh breeze will likely require Small Craft to
Exercise Caution, and Small Craft Advisory conditions possible in
the offshore (20-60 nm) waters. There is a 50-80% chance of rain
from Friday morning through Saturday night, with chances
decreasing through Sunday. On Sunday, winds shift northerly before
veering south by Tuesday morning. Marine conditions improve to
favorable by early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             35  44  38  51 /  10   0  30  60
HARLINGEN               32  43  36  50 /   0   0  30  80
MCALLEN                 35  45  36  47 /   0   0  20  70
RIO GRANDE CITY         32  47  35  46 /   0   0  10  50
SOUTH PADRE ISLAND      38  46  41  53 /  10  10  40  70
BAYVIEW/PORT ISABEL     34  43  38  52 /  10  10  40  70

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Cold Weather Advisory from midnight tonight to 9 AM CST Thursday
     for TXZ248>255-353.

     Freeze Warning from 3 AM to 9 AM CST Thursday for TXZ248>251-351.

     Cold Weather Advisory until 9 AM CST Thursday for TXZ351-354-355-
     451-454-455.

     High Rip Current Risk through Thursday afternoon for TXZ451-454-
     455.

     High Surf Advisory until 6 PM CST Thursday for TXZ451-454-455.

GM...Small Craft Advisory until noon CST Thursday for GMZ130-132-135-
     150-155-170-175.

&&

SHORT TERM...52-Goldsmith
LONG TERM....69-HK
AVIATION...23-Evbuoma