textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 524 PM CST Sun Feb 1 2026

- After the recent cool-down, an average to above-average week ahead, temperature-wise, with another front expected Wednesday but only a glancing blow of cooling through early Friday, mainly at night/morning

- Periodic difficult boating conditions, mainly Monday night into Tuesday ahead of the front and later Wednesday into Thursday behind it. - Overall dryness continues with potential increase in severe drought (level 2 of 4) coverage this week and next week, Any isolated light steamer showers along/near IH-69/US 77 Monday and early Tuesday, and perhaps some sprinkles behind the front Wednesday, will have no impact

- Moderate rip and south-to-north longshore currents through Tuesday, becoming high intensity post-front Wednesday into Thursday. Surf temperatures remaining chilly through the period.

DISCUSSION

Issued at 1259 PM CST Sun Feb 1 2026

After a ten-day period of steeper "roller-coaster" temperatures, a less dramatic day-by-day rise and fall will be the story this week. On the whole, temperatures will run a few ticks above normal from tonight through next Sunday, mainly driven by mild to warm afternoons on most days. In addition, any rain will be very light/sprinkly and favoring the coastal counties, early in the week and perhaps just behind the mid-week cold front. The main reason for this relatively "normal" forecast to begin February? First, flat westerly flow ahead of and behind a mini-500 mb ridge passing through Monday into Tuesday; second, as mentioned Saturday, the region sees only a glancing blow from the next in series of deepening eastern U.S. 500 mb troughs Wednesday into early Thursday before another mini-ridge arrives to close the week - then sets up shop for a few days in the southwestern Gulf.

Tonight through Tuesday Night: The transition from the cool/dry conditions of Friday through Sunday morning has begun, with areas of stratocumulus/altocumulus developing/moving across the region this afternoon and, with light easterly flow, holding temperatures in the 60s while dewpoints gradually rise. That trend completes overnight into early Monday, with overcast conditions for most and low level winds easing to the southeast, which will slow the fall of temperatures with morning lows at or a touch above average Monday (mid to upper 50s, except upper 40s-around 50 ranchlands). Increasing southeast flow Monday brings further rises in temperature and dewpoint, but lowering ceilings will hold maximum temperatures to a shade above average (mid 70s).

Pattern is also set up for low-topped isolated streamer showers along/near the IH-69E/US 77 corridor, but other than a brief ground- wetting, no impact. The transition to the warm side of the pillow completed overnight Monday with a continued southeast breeze and mostly cloudy conditions allowing temperatures to hold up well into the 60s. The clouds break/dissipate in slightly weaker southerly flow Tuesday, with temperatures shooting up into the 80s for most areas, for a ~10 degree above average day on the whole. The next front should arrive before daybreak across the ranchlands and around daybreak elsewhere, temperatures will drop back toward seasonal averages.

Wednesday through Friday morning: Northerly flow picks up Wednesday and we're likely to see mixed layers of clouds in all areas...with lowest decks near the coast in north-northeast flow. The depth and duration of the low clouds could present some temperature challenges, with some potential for highs to struggle out of the 60s. Farther west, enough sunshine mixing through higher level clouds should be sufficient to push highs toward or just above 70. Dry air clears out the clouds overnight into Thursday morning, with a return to chilly but fresh air and temperatures just a few degrees below average.

Full sunshine returns Thursday with lighter north winds making for a fantastic early February day - still a touch cool, but mitigated by the warming sun (which is also increasing in angle every day). This sets the stage for another refreshingly cool start Friday. With clear calm conditions, wind protected locations could drop back into the 30s...but air mass is not cold enough to imply a freeze/frost, even here.

Friday through Sunday: A perfect "Chamber of Commerce" Friday with a nice warmup under light variable winds and pleasant humidity, before southerly flow returns Saturday with a mix of clouds and sunshine and temperatures returning above normal by afternoon. Further warming arrives Sunday - with a continuation of partly sunny skies and a little be more humidity but still well within comfort as the "Valley Wind Machine" takes temporary hold.

AVIATION

(00Z TAFS) Issued at 524 PM CST Sun Feb 1 2026

East winds between 6 to 14 kts with stratuscumulus/altocumulus ceilings around 5kft prevail across the aerodromes early this evening. Ceilings may lower later tonight/around daybreak as low level moisture continues to increase. Light east winds overnight will increase and become southeasterly mid to late Monday morning. Some gusts around 25 kts will be likely as the pressure gradient strengthens across Deep South Texas. VFR conditions are expected for the next 24 hours.

MARINE

Issued at 1259 PM CST Sun Feb 1 2026

Tonight through Tuesday night: Light winds will become moderate by Monday as gradient picks up...but robust marine layer over the now- cooler nearshore waters should keep speeds down in the 10-15 knot range. This changes with the overnight reversal, especially beyond 20 nm where sea surface temperatures are a bit higher. May need a short-fused Advisory to cover the winds before conditions improve with the marine layer and decreasing gradient Tuesday and Tuesday night.

Wednesday through early Thursday: Gradient over the waters picks up fairly nicely behind the next front, and while temperatures advection (cold) is modest, the pressure gradient is sufficient for another round of low-end Small Craft Advisories for at least the outer leg (where additional overturning possible over ~70 degree SST). Default blends for the waters did not handle well, so matched up with neighboring grids north and south, and raised seas by a foot as well. These conditions begin Wednesday afternoon and prevail through the night.

Later Thursday through Friday Night: The quick movement of the surface ridge quickly settles winds and seas, making for improving conditions Thursday and ideal conditions Friday through Friday night. Boaters/fishers waiting for fantastic wind/wave/weather conditions will not have to wait any longer.

CLIMATE

Issued at 1259 PM CST Sun Feb 1 2026

As mentioned yesterday...January has finished, and the topsy-turvy nature of the final week was enough to pull top five (for most) warmest ranks through the 24th down a few pegs. That said, a several day window of 15-25 degree below average temperatures was not enough to lower rankings below the top 25% (quartile) - and when combined with December to take a look at meteorological (Dec-Feb) winter so far, most locations are in the top-fifteen warmest (top decile, or 10%, for most) - which is right in line with the overall December-February forecast expectations.

Here are select rankings for January 2026, and December 2025-January 2026:

January 2026

Location (since) Avg. Temp (Warmest Rank) Warmest (Year) Brownsville (1878) 64.5 (27th) 69.2 (1890) Harlingen (1912) 61.8 (36th) 70.2 (2023) McAllen (1942) 64.2 (18th) 70.4 (1950) Rio Grande City (1928/full) 58.1 (51st) 69.2 (1950) Raymondville (1913) 62.0 (29th) 68.6 (1952) Weslaco (1915) 61.7 (37th) 71.5 (1950) Port Mansfield (1958) 62.0 (10th) 65.3 (2000)

December 2025-January 2026 (ending year shown in "since"

Location (since) Avg. Temp (Warmest Rank) Warmest (Year) Brownsville (1879) 66.7 (8th) 70.2 (1890) Harlingen (1913) 64.0 (15th) 67.6 (1950) McAllen (1943) 66.5 (5th) 68.3 (1950) Rio Grande City (1929/full) 62.0 (15th) 66.8 (1950) Raymondville (1914) 63.7 (11th) 67.8 (1952) Weslaco (1915) 63.8 (15th) 69.3 (1950) Port Mansfield (1959) 63.6 (4th) 64.0 (1971)

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 55 74 64 78 / 0 10 0 0 HARLINGEN 50 75 59 80 / 0 0 0 0 MCALLEN 55 77 62 84 / 0 0 0 0 RIO GRANDE CITY 52 78 57 83 / 0 0 0 0 SOUTH PADRE ISLAND 59 69 64 72 / 0 10 0 0 BAYVIEW/PORT ISABEL 54 73 61 76 / 0 0 0 0

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.