textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 127 PM CDT Tue Jun 2 2026

* Intermittent low to moderate rain chances throughout the week, with the best chance being for areas west of I-69C on Friday.

* The Weather Prediction Center has portions of Deep South Texas in a Marginal (level 1 of 4) risk of excessive rainfall for Thursday evening into Friday, but due to low forecasted rain totals, confidence is very low of any isolated flooding. * Low to Moderate Heat Risk will be a concern throughout the week, despite seasonal high temperatures.

DISCUSSION

Issued at 127 PM CDT Tue Jun 2 2026

Surface troughing is expected to strengthen over the area as surface low pressure develops over the North Central Mexican desert and moves southeastward throughout the week. In addition, some mid to upper-level shortwave disturbances are expected to accompany a weak upper level low pressure system moving eastward from Baja. Moisture continues to increase throughout the area as southeasterly flow continues and tropical moisture moves more deeply into the area as well. All of these factors combined will contribute to an overall unsettled weather pattern and continued rain chances throughout the week.

Afternoon showers and perhaps a small thunderstorm or two are possible later this afternoon along the sea breeze, mainly east of I- 69C. Wednesday, low to moderate (20-40%) rain chances expand to most of Deep South Texas. Guidance has trended lower on rain chances for Thursday, but a low to moderate chance (30-50%) overnight into Friday exists for the Western Ranchlands. Friday looks to be the most likely day for precipitation, where chances could be as high as 60% for areas west of I-69C, likely due to Sierra Madre convection. Chances will be lower (20-30%) closer to the coast. Chances will diminish overnight to around 20-40% for most of Deep South Texas and will continue into Saturday, with the best chances east of I-69C.

Presently, the Weather Prediction Center has portions of the Western Ranchlands in a Marginal Risk (level 1 of 4) of excessive rainfall for Thursday evening, and all of Deep South Texas for Friday and Friday evening. Though the risk of isolated flash flooding with any heavier rainfall can't be completely ruled out at this time, confidence remains low, as QPF for the area remain relatively low. Areas that receive rain between Wednesday morning and Saturday morning are most likely to see between 0.5 and 1 inch over all three days. Some areas could see up to 2 inches where heavier rainfall occurs, and some areas may not see any rainfall at all due to the isolated to scattered nature of the convection. The atmosphere is expected to be robustly moist, with anomalous PWATS around 2 inches on Thursday and Friday. This will help to enhance the rain-making efficiency of any showers or thunderstorms that form, despite lower- forecasted QPF.

Heat Risk will be a concern through the weekend into next week, as humidity levels are expected to remain high which will make the temperatures outside feel warmer than they actually are. Though highs should remain mostly seasonal (upper 80s and lower 90s), "feels like" temperatures will be in the low to mid triple digits. This will support a Low (level 1 of 4) to Moderate (Level 2 of 4) Heat Risk throughout the week, with the highest risk over the weekend into early next week.

AVIATION

(18Z TAFS) Issued at 127 PM CDT Tue Jun 2 2026

VFR conditions are expected at all airports with some clouds and light to moderate southeasterly winds. Cloud cover is expected to increase between 00 and 02z, but ceiling are expected to remain VFR overnight.

MARINE

Issued at 127 PM CDT Tue Jun 2 2026

Favorable conditions are expected throughout the next week, with a low possibility of SCEC conditions early next week as winds slightly increase. There is a low (20-30%) chance of showers intermittently throughout the week both along the Bay and offshore. Winds should be east-southeasterly with low wave heights.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 78 90 77 90 / 10 30 10 10 HARLINGEN 75 90 74 90 / 10 30 10 10 MCALLEN 77 92 76 92 / 10 40 10 20 RIO GRANDE CITY 76 94 75 92 / 10 10 20 10 SOUTH PADRE ISLAND 81 85 80 85 / 20 20 10 0 BAYVIEW/PORT ISABEL 78 88 77 88 / 20 20 10 10

BRO WATCHES/WARNINGS/ADVISORIES

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