Current weather · Sep 27, 4:24 PM CDT

26.0810, -97.8280

98°

Partly SunnyFeels like 106° · Humidity 40%NWS forecast for this hour; no recent station reportForecast by NWS Brownsville/Rio Grande Valley, TX · grid 65,13
High
99°
Low
76°
Rain today
7%
Sunrise
7:22 AM
Sunset
7:22 PM

Hour by hour

NWS forecast grid

Scroll sideways for more hours. Pick an hour for every number.

Every hour as a table48 hours
TimeWeatherTemperatureFeels likeDew pointHumidityChanceAmountSnowDirWindGustSky coverThunderPressureVisibilityCeiling
Sun 4 PM98°106°70°40%6%E9 mph15 mph61%6%——
Sun 5 PM96°104°71°44%7%E12 mph18 mph67%7%——
Sun 6 PM94°102°71°48%4%E13 mph21 mph34%4%——
Sun 7 PM92°99°72°52%1%E13 mph22 mph38%1%——
Sun 8 PM86°93°73°64%0%ESE10 mph20 mph59%——
Sun 9 PM85°91°73°68%0%ESE8 mph17 mph34%——
Sun 10 PM84°90°73°71%0%SE6 mph14 mph28%——
Sun 11 PM82°88°74°74%0%SE5 mph12 mph23%——
Mon 12 AM81°87°73°77%0%SE3 mph10 mph19%——
Mon 1 AM80°85°74°79%0%SSE3 mph9 mph45%——
Mon 2 AM80°84°74°82%0%SE3 mph8 mph28%——
Mon 3 AM78°78°74°86%0%SE3 mph7 mph13%——
Mon 4 AM78°78°74°88%0%ESE2 mph7 mph12%——
Mon 5 AM77°77°74°89%0%ESE2 mph6 mph37%——
Mon 6 AM76°77°74°91%0%E2 mph6 mph30%——
Mon 7 AM76°77°74°91%2%E2 mph6 mph14%2%——
Mon 8 AM77°77°75°92%3%E3 mph6 mph25%2%——
Mon 9 AM82°89°76°84%4%ESE3 mph6 mph33%2%——
Mon 10 AM87°96°76°70%3%SE3 mph7 mph38%3%——
Mon 11 AM91°101°74°56%2%SE5 mph9 mph38%2%——
Mon 12 PM94°102°72°49%3%ESE6 mph10 mph28%3%——
Mon 1 PM96°104°71°44%12%0.02 inESE6 mph12 mph35%12%——
Mon 2 PMSlight chance of light rain showers98°106°70°41%15%0.02 inE8 mph14 mph33%13%——
Mon 3 PMSlight chance of light rain showers97°105°70°42%17%0.02 inE9 mph17 mph42%13%——
Mon 4 PM97°104°71°44%9%0.02 inESE13 mph22 mph35%9%——
Mon 5 PM95°103°71°46%8%0.02 inE14 mph23 mph28%8%——
Mon 6 PM92°100°72°51%4%0.02 inESE15 mph24 mph27%4%——
Mon 7 PM89°97°72°57%1%ESE15 mph24 mph30%1%——
Mon 8 PM86°93°73°67%0%ESE13 mph22 mph31%——
Mon 9 PM84°92°74°71%0%ESE10 mph20 mph26%——
Mon 10 PM84°91°75°74%0%ESE8 mph17 mph21%——
Mon 11 PM83°90°75°77%0%ESE7 mph15 mph18%——
Tue 12 AM82°89°75°78%1%SE6 mph14 mph22%1%——
Tue 1 AM81°88°75°81%8%0.01 inSE6 mph13 mph22%3%——
Tue 2 AM81°87°75°83%7%0.01 inSE6 mph13 mph20%3%——
Tue 3 AM80°84°75°86%0%0.01 inSE6 mph13 mph30%——
Tue 4 AM79°79°75°88%10%0.01 inSE6 mph14 mph37%5%——
Tue 5 AMSlight chance of light rain showers79°79°75°88%15%0.01 inSE6 mph13 mph20%5%——
Tue 6 AMSlight chance of light rain showers78°78°75°93%17%0.01 inSE6 mph13 mph19%5%——
Tue 7 AMSlight chance of light rain showers78°78°75°92%19%SE6 mph13 mph36%4%——
Tue 8 AMSlight chance of light rain showers78°78°76°93%19%SE6 mph13 mph0%4%——
Tue 9 AMSlight chance of light rain showers82°90°77°84%19%SE7 mph15 mph15%4%——
Tue 10 AMSlight chance of light rain showers87°99°77°72%19%SE9 mph17 mph30%9%——
Tue 11 AMSlight chance of light rain showers91°104°76°62%19%SE10 mph20 mph37%9%——
Tue 12 PMSlight chance of light rain showers94°106°75°54%19%SE12 mph22 mph44%9%——
Tue 1 PMSlight chance of thunderstorms and slight chance of light rain showers96°108°74°49%21%SE13 mph24 mph51%21%——
Tue 2 PMSlight chance of thunderstorms and slight chance of light rain showers98°109°73°46%21%SE14 mph26 mph46%21%——
Tue 3 PMSlight chance of thunderstorms and slight chance of light rain showers98°109°73°45%21%SE15 mph28 mph41%21%——

The next 16 days

NWS grid published Sep 27, 4:18 PM CDT to day 8, the National Blend of Models to day 11, the mean of GFS, ECMWF, ECMWF AI to day 16
  1. TodaySep 2799°76°Partly Sunny7%wind 13 mph · gusts 22 mph
  2. MonSep 2899°77°Mostly Sunny then Slight Chance Rain Showers17%0.13 inwind 15 mph · gusts 24 mph
  3. TueSep 2999°79°Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms21%0.07 inwind 17 mph · gusts 29 mph
  4. WedSep 3099°80°Mostly Sunny7%wind 21 mph · gusts 36 mph
  5. ThuOct 198°77°Slight Chance Showers And Thunderstorms66%0.84 inwind 18 mph · gusts 31 mph
  6. FriOct 293°73°Showers And Thunderstorms77%1.22 inwind 10 mph · gusts 22 mph
  7. SatOct 389°72°Rain Showers Likely60%0.77 inwind 12 mph · gusts 23 mph
  8. SunOct 490°73°48%0.45 inwind 12 mph · gusts 23 mph
  9. MonOct 589°72°National Blend44%0.37 inwind 13 mph · gusts 26 mph
  10. TueOct 689°71°National Blend36%0.48 inwind 14 mph · gusts 28 mph
  11. WedOct 790°70°National Blend28%0.56 inwind 13 mph · gusts 24 mph
  12. ThuOct 8~89°75°Model mean0.56 in
  13. FriOct 9~79°70°Model mean0.44 in
  14. SatOct 10~79°66°Model mean0.05 in
  15. SunOct 11~79°67°Model mean
  16. MonOct 12~80°62°Model mean

Right now

NWS grid for this hour · UV from the EPA · air quality from AirNow
  • Feels like106°
  • WindE 9 mphgusts 15 mph
  • Radar over this pointno reading
  • Humidity40%
  • Dew point70°
  • Pressure—
  • UV index—
  • Air quality—
  • Visibility—
  • Sunrise and sunsetSunrise · Sunset
  • Moonrise7:55 PMMoonset 8:14 AM
  • Moon phaseWaning gibbous99% lit

The National Blend of Models

NOAA NBM v5.0 · run of Sep 27, 1:00 PM CDT

NOAA’s weighted blend of every model it runs, to eleven days, with the chances the grid above does not carry. Where the local office’s grid reaches, its figure sits beneath the blend’s; where it does not, the blend stands alone.

  1. TodaySep 27—76°NWS grid 99° / 76°rain 6%thunder 17%wind 13 mph · gusts 22 mph
  2. MonSep 2899°77°NWS grid 99° / 77°rain 28%thunder 17%0.13 inwind 15 mph · gusts 24 mph
  3. TueSep 2999°79°NWS grid 99° / 79°rain 35%thunder 23%0.07 inwind 17 mph · gusts 29 mph
  4. WedSep 3099°80°NWS grid 99° / 80°rain 8%thunder 26%wind 21 mph · gusts 36 mph
  5. ThuOct 198°77°NWS grid 98° / 77°rain 72%thunder 53%0.94 inwind 18 mph · gusts 31 mph
  6. FriOct 293°73°NWS grid 93° / 73°rain 77%thunder 38%1.17 inwind 10 mph · gusts 22 mph
  7. SatOct 389°72°NWS grid 89° / 72°rain 59%thunder 37%0.84 inwind 12 mph · gusts 23 mph
  8. SunOct 490°72°NWS grid 90° / 73°rain 48%thunder 26%0.41 inwind 12 mph · gusts 23 mph
  9. MonOct 589°72°Beyond the NWS gridrain 44%thunder 10%0.37 inwind 13 mph · gusts 26 mph
  10. TueOct 689°71°Beyond the NWS gridrain 36%0.48 inwind 14 mph · gusts 28 mph
  11. WedOct 790°70°Beyond the NWS gridrain 28%0.56 inwind 13 mph · gusts 24 mph
68°86°104°MonTueWedThuFriSatSun

BlendNWS gridChance of rain, hourly

The models, side by side

HRRR Sep 27, 1:00 PM CDT · GFS Sep 27, 7:00 AM CDT · GEFS Sep 27, 7:00 AM CDT · ECMWF Sep 27, 7:00 AM CDT · ECMWF AI Sep 27, 7:00 AM CDT

Each line is one model’s own forecast at its own grid cell: three kilometers for HRRR, a quarter of a degree for the global models, which can sit a few hundred meters above or below the town. Where they agree the forecast is settled; where they part is where it is not.

68°86°104°MonTueWedThuFriSatSun

DayNWS gridHRRRGFSGEFSECMWFECMWF AI
Today Sep 2799° 76°100° 83°98° 80°95° 79°94° 78°0.08 in~95° 77°
Mon Sep 2899° 77°0.13 in99° 78°96° 79°93° 79°0.01 in94° 77°~96° 78°0.02 in
Tue Sep 2999° 79°0.07 in96° 77°95° 81°0.02 in92° 81°0.01 in95° 79°0.05 in~95° 80°0.07 in
Wed Sep 3099° 80°—94° 82°93° 82°0.01 in96° 82°~96° 82°0.07 in
Thu Oct 198° 77°0.84 in—94° 79°0.63 in91° 82°0.25 in95° 80°0.29 in~94° 82°0.30 in
Fri Oct 293° 73°1.22 in—80° 77°0.46 in88° 80°0.45 in90° 74°0.35 in~89° 77°0.37 in
Sat Oct 389° 72°0.77 in—85° 74°0.52 in83° 76°0.23 in~89° 75°0.30 in~88° 77°0.38 in
Sun Oct 490° 73°0.45 in—86° 74°83° 75°0.12 in~89° 74°0.28 in~88° 77°0.41 in
Mon Oct 5——87° 73°83° 75°0.19 in~89° 75°0.26 in~85° 78°0.72 in
Tue Oct 6——89° 72°84° 74°0.31 in~85° 75°0.21 in~85° 77°0.55 in
Wed Oct 7——~88° 73°~75° 73°0.03 in~90° 76°0.06 in~88° 77°0.31 in
Thu Oct 8——~88° 70°—~90° 76°1.39 in~90° 77°0.29 in
Fri Oct 9——~82° 70°0.27 in—~75° 65°~80° 76°1.06 in
Sat Oct 10——~76° 66°—~77° 60°~83° 73°0.15 in
Sun Oct 11——~71° 65°—~81° 67°~85° 70°
Mon Oct 12——~80° 62°—~70° 68°~69° 67°

A ~ marks a high or low read from six-hourly steps, which miss the true extreme by a degree or two.

ECMWF ensemble meteogram

ECMWF ensemble meteogram for this place: box plots of cloud cover, precipitation, wind speed and temperature from the 51 ensemble members for ten days.
Rendered by ECMWF from its 51-member ensemble, in metric units: each box spans the middle half of the members, the whiskers the rest, the line the control run. A forecast, not an observation. © ECMWF, CC BY 4.0.

The next 90 days

NOAA GHCN normals and records at Weslaco (TXW) · Climate Prediction Center outlooks

No forecast has skill day by day past about two weeks, and this page does not print one. Where the models stop, the calendar takes over: the 1991 to 2020 normal for each date, the record high and low ever set on it, and where the Climate Prediction Center leans warm, cool, wet or dry over the coming weeks, the month and the season. A site that shows a high for a date three months out is showing you this normal with a wobble.

The forecast reaches Mon Oct 12, from the NWS grid, then the National Blend, then the mean of the global models. Beyond it the lines are the calendar.

Climate Prediction Center (CPC) temperature lean33%warmer 40% · Oct 2026equal chances · Oct to Dec20°40°60°80°100°TodayOct 1Nov 1Dec 1

Forecast high and lowNormal high and lowRecord high and lowCPC leans warmer than normalCPC leans cooler than normalCPC near normal or equal chances

Week ofNormalWarmest on recordColdest on recordTemperature leanPrecipitation lean
Sep 2789° / 68°101° (2011)48° (1942)no outlookno outlook
Oct 489° / 68°100° (1990)43° (1952)near normal most likely · days 6 to 1050% chance above normal · days 6 to 10
Oct 1190° / 65°98° (1993)40° (1944)40% chance above normal · Oct 202640% chance above normal · Oct 2026
Oct 18—104° (2012)42° (1917)40% chance above normal · Oct 202640% chance above normal · Oct 2026
Oct 2583° / 61°98° (1942)33° (1993)40% chance above normal · Oct 202640% chance above normal · Oct 2026
Nov 178° / 59°99° (1988)32° (1951)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Nov 882° / 60°99° (1989)33° (1916)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Nov 1577° / 56°93° (1938)30° (1940)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Nov 22—94° (1994)30° (1938)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Nov 2974° / 53°94° (2016)28° (1957)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Dec 6—94° (1939)24° (1950)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Dec 1374° / 51°90° (1921)27° (1996)equal chances · Oct to Dec40% chance above normal · Oct to Dec
Dec 20—91° (1945)16° (1989)equal chances · Oct to Dec40% chance above normal · Oct to Dec

Health and activities

Rules of thumb over the next 24 hours of forecast, the warnings in force, the station’s report, air quality and pollen

None of these is a measurement. Each is a rating of the forecast ahead, and of what is happening at the point right now, against what the activity or the ailment is known to mind, and each names the figure that decided it. An ailment or a pest is rated as a risk, low to extreme; an activity, a chore or a journey as a condition, poor to ideal.

Each rating says which span it is for: the rest of today’s daylight, tonight, or the next 24 hours.

Health

  • Arthritisnext 24 hModeratehumid
  • Sinus pressurenext 24 hLowsteady conditions
  • Common coldtodayLowmild
  • FlutodayLowmild
  • Migrainenext 24 hModerateheat
  • Asthmanext 24 hLowclean air
  • Heat stresstodayExtremeheat
  • SunburntodayLowweak sun
  • Frostbitenext 24 hLowmild
  • SleepingtonightFairwarm night

Outdoors

  • RunningtodayFairhot
  • HikingtodayGoodhot
  • BikingtodayVery goodhot
  • GolftodayVery goodhot
  • FishingtodayIdealfine conditions
  • Boating and paddlingtodayGoodwind
  • Beach and pooltodayIdealfine conditions
  • CampingtonightIdealfine conditions
  • StargazingtonightFairbright moon

Travel

  • Air travelnext 24 hIdealclear skies
  • Drivingnext 24 hIdealclear roads

Home and garden

  • Lawn mowingtodayVery goodhot
  • GardeningtodayVery goodhot
  • Outdoor entertainingtodayVery goodhot
  • Drying laundry outsidetodayVery goodlittle sun
  • Painting and outdoor projectstodayVery goodhot
  • FrosttonightLowmild

Pests

  • MosquitoestodayHighwarm
  • TickstodayModeratewarm
  • Indoor pestsnext 24 hLowmild
  • Outdoor peststodayHighwarm

Stargazing

Worked out from the NWS hourly forecast and the sun and moon

Tonight has no dark, clear hour without a bright moon in this forecast. Rated fair.

Night ofRatingDarkClear hoursClear and moonlessMoon litTransparency (est.)DewStrongest wind
SundayFair8:39 PM to 6:06 AM3 of 9None98%Poor1 h8 mph
MondayFair8:37 PM to 6:06 AM3 of 9None93%Fair10 mph
TuesdayPoor8:36 PM to 6:07 AM0 of 9None87%16 mph
WednesdayPoor8:35 PM to 6:07 AM0 of 9None79%20 mph
ThursdayPoor8:34 PM to 6:08 AM0 of 9None70%2 h10 mph
FridayPoor8:33 PM to 6:08 AM0 of 9None60%2 h8 mph
SaturdayPoor8:32 PM to 6:09 AM0 of 9None49%2 h9 mph

Dark is the sun 18 degrees below the horizon; where it never gets that low, 12 degrees, marked nautical. Clear is sky cover of 20% or less. A bright moon is one above the horizon with a quarter or more of its disc lit. Transparency in the table is estimated from surface humidity (70% and 85% mark fair and poor) and visibility, since the forecast carries no haze or high cloud moisture. Seeing and transparency by hour, where shown, are Environment and Climate Change Canada’s astronomy forecast (regional model; seeing from cloud, wind shear, turbulence near the ground and the surface temperature trend; transparency from the moisture through the whole air column), under the Open Government Licence - Canada. Dew is the air within 2 °C of its dew point. Excellent is four or more clear moonless hours with good transparency; good is three; fair is one, or two clear hours.

Golden hour and blue hour

Computed from the sun and moon positions
DayBlue hour, morningGolden hour, morningGolden hour, eveningBlue hour, evening
Sun6:59 AM to 7:08 AM7:08 AM to 7:53 AM6:52 PM to 7:36 PM7:36 PM to 7:45 PM
Mon6:59 AM to 7:08 AM7:08 AM to 7:53 AM6:50 PM to 7:35 PM7:35 PM to 7:44 PM
Tue7:00 AM to 7:09 AM7:09 AM to 7:53 AM6:49 PM to 7:34 PM7:34 PM to 7:43 PM
Wed7:00 AM to 7:09 AM7:09 AM to 7:54 AM6:48 PM to 7:33 PM7:33 PM to 7:42 PM
Thu7:01 AM to 7:10 AM7:10 AM to 7:54 AM6:47 PM to 7:32 PM7:32 PM to 7:41 PM
Fri7:01 AM to 7:10 AM7:10 AM to 7:55 AM6:46 PM to 7:31 PM7:31 PM to 7:40 PM
Sat7:02 AM to 7:10 AM7:10 AM to 7:55 AM6:45 PM to 7:30 PM7:30 PM to 7:39 PM
NESWSRSSMRMS
  • SR Sunrise 7:22 AM, 92° E
  • SS Sunset 7:22 PM, 268° W
  • MR Moonrise 7:55 PM, 76° ENE
  • MS Moonset 8:14 AM, 280° W
  • Waning gibbous, 99% lit

Golden hour is the sun between 6 degrees above the horizon and 4 degrees below it; blue hour is the sun between 4 and 6 degrees below. These are the definitions timeanddate.com and PhotoPills use. Directions are degrees clockwise from true north, where the sun’s upper edge and the moon’s center cross a flat horizon; hills and buildings change both. None means the sun does not reach that height on the day; all day means it stays inside the band.

Drone flying

NWS hourly forecast, SWPC Kp, FAA TFRs and 14 CFR Part 107

This hour: good to fly. Next good stretch: Mon 8 AM to 1 PM, 5 hours.

Today: civil twilight for Part 107 6:52 AM to sunrise 7:22 AM, and sunset 7:22 PM to 7:52 PM. Anti-collision lighting is required in those minutes and at night.

Sun6 PM
Mon12 AM6 AM12 PM6 PM
Tue12 AM6 AM12 PM6 PM

Good Caution No-fly

HourVerdictWind (mph)400 ft est. (mph)Gust (mph)RainVisibilityCloud allowsTempKpWhy
Sun 4 PMGood912186%98°nothing against it
Sun 5 PMCaution1217247%96°gusts near or over your limit
Sun 6 PMNo-fly1318264%94°gusts near or over your limit, wind at 400 ft near or over your limit
Sun 7 PMNo-fly1318281%92°gusts near or over your limit, wind at 400 ft near or over your limit, night: lighting and night training required (107.29)
Sun 8 PMNo-fly1015240%86°gusts near or over your limit, night: lighting and night training required (107.29)
Sun 9 PMNo-fly819290%85°gusts near or over your limit, wind at 400 ft near or over your limit, night: lighting and night training required (107.29)
Sun 10 PMNo-fly623310%84°gusts near or over your limit, wind at 400 ft near or over your limit, night: lighting and night training required (107.29)
Sun 11 PMNo-fly518250%82°gusts near or over your limit, wind at 400 ft near or over your limit, night: lighting and night training required (107.29)
Mon 12 AMCaution314210%81°gusts near or over your limit, night: lighting and night training required (107.29)
Mon 1 AMCaution314190%80°gusts near or over your limit, night: lighting and night training required (107.29)
Mon 2 AMCaution314180%80°gusts near or over your limit, night: lighting and night training required (107.29)
Mon 3 AMCaution314170%78°night: lighting and night training required (107.29)
Mon 4 AMCaution29140%78°night: lighting and night training required (107.29)
Mon 5 AMCaution29130%77°night: lighting and night training required (107.29)
Mon 6 AMCaution29130%76°night: lighting and night training required (107.29)
Mon 7 AMCaution2362%76°civil twilight: lighting required (107.29)
Mon 8 AMGood3463%77°nothing against it
Mon 9 AMGood3464%82°nothing against it
Mon 10 AMGood3483%87°nothing against it
Mon 11 AMGood55102%91°nothing against it
Mon 12 PMGood67113%94°nothing against it
Mon 1 PMCaution671312%96°thunderstorms possible
Mon 2 PMCaution8101515%98°thunderstorms possible
Mon 3 PMCaution9111917%97°gusts near or over your limit, thunderstorms possible

Flight restrictions nearby

Reading the FAA’s temporary flight restrictions.

Flight restrictions on the map. TFRs are not the whole picture: controlled airspace around airports needs LAANC authorization. Check the FAA’s B4UFLY.

Wind at 400 ft is estimated from the 10 m forecast by the power law, with exponents for each Pasquill stability class (Irwin 1979, rural, as in EPA dispersion models; the class from wind, sun height and cloud, after Turner 1970); gusts keep the ground gust’s margin. Caution from three quarters of your limit; the default 24 mph is the wind resistance printed for common sub-250 g drones. 14 CFR 107.51: “The minimum flight visibility, as observed from the location of the control station must be no less than 3 statute miles” and at least “500 feet below the cloud”. 14 CFR 107.29: “No person may operate a small unmanned aircraft system during periods of civil twilight unless the small unmanned aircraft has lighted anti-collision lighting visible for at least 3 statute miles”; civil twilight is the 30 minutes before sunrise and after sunset, in Alaska the Air Almanac’s. Kp: SWPC’s scales say satellite navigation problems may occur at G3 (Kp 7) and navigation is “degraded for hours” at G4 (Kp 8); Kp 5 is the typical app warning. Typical limits, not rules: rain chance 30% caution and 60% no-fly, thunder 10% and 20%, below 0 °C caution and −10 °C no-fly, over 40 °C caution. Your drone’s manual and the airspace come first.

Spraying and field work

Worked out from the NWS hourly forecast

Hours fit for spraying, and the days dry enough for fieldwork and hay, read from this forecast’s wind, gusts, humidity, temperature and rain.

Spraying windows

  • Sun 10 PM to Mon 3 AM 5 hours, every hour within the rules
Sun6 PM
Mon12 AM6 AM12 PM6 PM
Tue12 AM6 AM12 PM6 PM
Wed12 AM6 AM12 PM6 PM

Good Marginal No

Field days

DayDaytimeChance of rainRainLowest humidityStrongest windDry days in a rowHay drying
SundayDry7%0.00 in40%13 mph1 dGood
MondayShowers possible17%0.13 in41%15 mph
TuesdayShowers possible21%0.07 in45%17 mph
WednesdayDry7%0.00 in47%21 mph1 dGood
ThursdayWet66%0.84 in50%16 mph
FridayWet77%1.22 in54%10 mph
SaturdayWet59%0.77 in56%12 mph
SundayWet48%0.45 in55%12 mph

Spraying: sustained wind 3 to 10 mph, the range US extension services and most labels give; gusts no more than 15 mph (this page’s limit); delta T (air minus wet-bulb temperature) 2 to 8 °C preferred and 8 to 10 °C marginal, from GRDC guidance, with the wet bulb by Stull’s formula; no hour at a 30% chance of rain or 0.25 mm forecast during the rain-free time. Follow the product label, which overrides all of this. Field days: dry is no daytime hour at a 30% chance and under 1 mm all day, wet is 6 mm (0.25 in) or more; soil moisture is not in the forecast, so ground still wet from earlier rain is not accounted for. Hay drying marks a dry day with humidity down to 50% and a breeze of 5 mph or more.

Solunar times

Computed from the moon’s position

The best-rated day this week is Sunday, rated best.

DayRatingMajor periodsMinor periodsMoonSunrise, sunset
Sun Best12:44 AM to 2:44 AM1:08 PM to 3:08 PM7:44 AM to 8:44 AM7:25 PM to 8:25 PM 99%7:22 AM, 7:22 PM
Mon Good1:32 AM to 3:32 AM1:58 PM to 3:58 PM8:47 AM to 9:47 AM8:03 PM to 9:03 PM 95%7:22 AM, 7:21 PM
Tue Fair2:24 AM to 4:24 AM2:52 PM to 4:52 PM9:52 AM to 10:52 AM8:47 PM to 9:47 PM 90%7:23 AM, 7:20 PM
Wed Poor3:20 AM to 5:20 AM3:50 PM to 5:50 PM11:00 AM to 12:00 PM9:38 PM to 10:38 PM 82%7:23 AM, 7:19 PM
Thu Fair4:21 AM to 6:21 AM4:52 PM to 6:52 PM12:07 PM to 1:07 PM10:36 PM to 11:36 PM 73%7:24 AM, 7:18 PM
Fri Fair5:23 AM to 7:23 AM5:55 PM to 7:55 PM1:11 PM to 2:11 PM 64%7:24 AM, 7:17 PM
Sat Fair6:26 AM to 8:26 AM6:56 PM to 8:56 PM11:39 PM to 12:39 AM2:09 PM to 3:09 PM 53%7:25 AM, 7:16 PM

Periods in bold fall within an hour of sunrise or sunset. The weather’s side is the fishing index

Major periods are two hours centered on the moon’s passage overhead and underfoot; minor periods are one hour centered on moonrise and moonset: the conventional durations of John Alden Knight’s solunar tables (1936). The rating is this site’s: one point to start, two more within a day and a half of a new or full moon (one more within three and a half days), and one more when a period falls within an hour of sunrise or sunset. The theory has mixed support in fisheries research; the times are exact astronomy.

In words

NWS forecast periods, as issued
  1. This Afternoon99° · 7% · E 12 mph

    Partly sunny, with a high near 99. Heat index values as high as 106. East wind around 12 mph.

  2. Tonight76° · 4% · SE 2–13 mph

    Partly cloudy, with a low around 76. Southeast wind 2 to 13 mph, with gusts as high as 22 mph.

  3. Monday99° · 17% · ESE 2–14 mph

    A slight chance of rain showers between 2pm and 4pm. Mostly sunny. High near 99, with temperatures falling to around 95 in the afternoon. Heat index values as high as 106. East southeast wind 2 to 14 mph, with gusts as high as 23 mph. Chance of precipitation is 20%.

  4. Monday Night77° · 15% · SE 6–15 mph

    A slight chance of rain showers after 5am. Partly cloudy, with a low around 77. Southeast wind 6 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 20%.

  5. Tuesday99° · 21% · SE 6–17 mph

    A slight chance of rain showers before 1pm, then a slight chance of showers and thunderstorms. Mostly sunny, with a high near 99. Southeast wind 6 to 17 mph, with gusts as high as 29 mph. Chance of precipitation is 20%.

  6. Tuesday Night79° · 21% · SE 14–17 mph

    A slight chance of showers and thunderstorms before 7pm. Partly cloudy, with a low around 79. Southeast wind 14 to 17 mph, with gusts as high as 29 mph. Chance of precipitation is 20%.

  7. Wednesday99° · 7% · SSE 14–21 mph

    Mostly sunny, with a high near 99. South southeast wind 14 to 21 mph, with gusts as high as 36 mph.

  8. Wednesday Night80° · 15% · SE 14–20 mph

    A slight chance of rain showers after 1am. Partly cloudy, with a low around 80. Southeast wind 14 to 20 mph, with gusts as high as 33 mph. Chance of precipitation is 20%.

  9. Thursday98° · 66% · SE 16 mph

    A slight chance of rain showers before 7am, then a slight chance of showers and thunderstorms between 7am and 1pm, then showers and thunderstorms likely. Partly sunny, with a high near 98. Southeast wind around 16 mph, with gusts as high as 29 mph. Chance of precipitation is 70%.

  10. Thursday Night77° · 69% · S 5–14 mph

    Showers and thunderstorms likely. Mostly cloudy, with a low around 77. South wind 5 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 70%.

  11. Friday93° · 77% · N 5–10 mph

    Showers and thunderstorms. Mostly cloudy, with a high near 93. North wind 5 to 10 mph, with gusts as high as 22 mph. Chance of precipitation is 80%.

  12. Friday Night73° · 77% · N 5–9 mph

    Showers and thunderstorms. Mostly cloudy, with a low around 73. Chance of precipitation is 80%.

  13. Saturday89° · 60% · NNW 12 mph

    Rain showers likely before 1pm, then showers and thunderstorms likely. Partly sunny, with a high near 89. Chance of precipitation is 60%.

  14. Saturday Night72° · 59% · NNW 6–9 mph

    Showers and thunderstorms likely. Mostly cloudy, with a low around 72.

The forecaster’s discussion

NWS Brownsville/Rio Grande Valley, TX · issued Sep 27, 1:39 PM CDT

Written by the forecaster on duty for their own colleagues and for anyone who wants to know why the forecast says what it says. It is not edited for the public, so it uses the office’s shorthand; it is also the most honest thing any weather service publishes.

KEY Messages

Updated at 125 PM CDT Sun Sep 27 2026

Hot and humid conditions continue through midweek. Heat indices of 110+ degrees on Tuesday and Wednesday afternoons.

A wetter pattern is looking more likely Thursday into the weekend, with widespread 60-80% rain chances.

There is a Marginal to Slight (levels 1 and 2 out of 4) risk of excessive rainfall later this week.

Discussion

125 PM CDT Sun Sep 27 2026

September will close out hot and mostly dry as ridging in the mid- upper levels remains dominant over deep South Texas. An isolated shower or thunderstorm along the sea breeze cannot be ruled out each afternoon into Tuesday. For the latter half of the week into the weekend, things get more interesting.

A trough over the desert southwest will ingest tropical moisture from the Pacific as it digs into West Texas early this week, bringing along with it a cold front. Midweek, the front is anticipated to stall over central Texas, which pulling Gulf moisture into the region. PWAT values in the latter half of the week could range from 2.3-2.6", nearing climatological maximum values for early October. Mid-level weakness will provide instability to support an increased chance of showers and thunderstorms across the region. Model guidance has continued to suggest heavy rainfall in Texas in the latter half of this week. However, being over 3 days out from the onset of any expected impacts over deep S TX, there remains uncertainty on the timing and axis of the heaviest rainfall. Latest guidance suggests this axis of rainfall will be heaviest to the north of deep S TX, but the forecast will continue to be monitored.

For deep S TX, widespread showers could come as early as late Wednesday, but more likely Thursday or Friday, with moderate to high PoPs continuing into the weekend. This will hopefully bring very welcome rain we've been missing, but training or heavy showers/storms can lead to flooding in low lying, poor drainage, and urban areas. The Weather Prediction Center has placed the region in a Marginal Risk (level 1 of 4) Wednesday, and a Slight Risk (2 of 4) Thursday of excessive rainfall leading to flash flooding.

Hot temperatures with heat indices in the triple digits are expected to continue into midweek, increasing as moisture builds ahead of the front. SPSs are possible Tuesday and Wednesday, and apparent temperatures above 111 degF are possible for brief periods. Increased cloud cover will limit temperatures, but it will still be warm and humid with highs later this week in the 90s.

Local beaches remain pleasant early this week, but will degrade as the front approaches. An increased risk of life threatening rip currents is likely, and increased wave heights may lead to concerns for minor coastal flooding.

Aviation

1215 PM CDT Sun Sep 27 2026

(18Z TAFS)

VFR conditions prevail. East-southeasterly winds this afternoon diminish overnight to light and variable, primarily out of the east. There is a low (less than 30%) chance of MVFR ceilings at HRL around sunrise Monday.

Marine

125 PM CDT Sun Sep 27 2026

Gentle to moderate south-southeasterly flow with slight seas prevail through Tuesday morning. An increasing pressure gradient will degrade conditions by midweek, with Small Craft Advisory conditions possible as early as Tuesday night with seas building to 4-7 ft. Low rain chances (20% or less) will continue through Monday, increasing Tuesday onwards. Rain chances increase to low-moderate (30%) through Wednesday, further increasing to moderate-high (60-80%) Thursday through the remainder of the period. Under any thunderstorms, expect locally higher winds and seas.

Preliminary Point Temps / Pops

BROWNSVILLE 79 96 80 97 / 0 30 30 20 HARLINGEN 74 99 76 100 / 0 10 20 30 MCALLEN 78 102 80 102 / 0 10 10 20 RIO GRANDE CITY 77 102 78 103 / 0 0 0 10 SOUTH PADRE ISLAND 81 89 82 90 / 0 20 30 20 BAYVIEW/PORT ISABEL 77 94 79 95 / 0 10 20 20

BRO Watches / Warnings / Advisories

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

The outlooks beyond

SPC, WPC, CPC and the Drought Monitor, read at this point

The national centers each publish a judgment the local grid does not carry. Read here at this exact coordinate.

Severe weather

  1. Day 1 · Sun Sep 27No risk area
  2. Day 2 · Mon Sep 28No risk area
  3. Day 3 · Tue Sep 29General Thunderstorms Risk
  4. Day 4 · Wed Sep 30No risk area
  5. Day 5 · Thu Oct 1No risk area
  6. Day 6 · Fri Oct 2No risk area
  7. Day 7 · Sat Oct 3No risk area
  8. Day 8 · Sun Oct 4No risk area

Rainfall

  1. Day 1 · Sun Sep 270.01 in
  2. Day 2 · Mon Sep 280.01 in
  3. Day 3 · Tue Sep 29Under 0.01 in
  4. Day 4-5 · Sep 30–Oct 11.75 in
  5. Day 6-7 · Oct 2–Oct 31.25 in

The rainfall forecast on the map, days 1 to 7

Flash flood risk

  1. Day 1 · Sun Sep 27Below marginal
  2. Day 2 · Mon Sep 28Below marginal
  3. Day 3 · Tue Sep 29Below marginal
  4. Day 4 · Wed Sep 30Below marginal
  5. Day 5 · Thu Oct 1Slight

Six to fourteen days

  1. Days 6–10 · TemperatureNear normal most likelyOct 3–Oct 7
  2. Days 6–10 · Precipitation50% chance above normalOct 3–Oct 7
  3. Days 8–14 · Temperature33% chance below normalOct 5–Oct 11
  4. Days 8–14 · Precipitation33% chance above normalOct 5–Oct 11

Hazards, 3 to 14 days

  1. Sep 30–Oct 4Severe Drought

Drought

  1. Drought Monitor, map of Sep 22D4 Exceptional drought
  2. Outlook for Sep 2026Drought persists

Drought in this county: the map, the record since 2000 and the outlook

Frost and climate

NOAA 1991-2020 normals, Harlingen

A freeze (32°F or colder) comes in only 31 percent of years here.

Climate of 26.08, -97.83: normals, records and every month

Everything else on the grid

NWS forecast grid · 25 elements

The forecast office edits about sixty fields for every cell of its grid. The common ones are above; these are the rest, as the daily extreme, for anyone who needs the mixing height, the fire danger or the swell.

ElementSunMonTueWedThuFriSatSun
HeatRisk max2 · Moderate3 · Major3 · Major4 · Extreme4 · Extreme4 · Extreme2 · Moderate1 · Minor
Wet bulb globe temperature max90°89°89°90°89°85°83°83°
Heat index max106°106°109°111°109°100°94°95°
Chance of thunder max7%13%21%7%44%32%31%28%
Mixing height max7,900 ft7,000 ft7,300 ft6,800 ft
Transport wind max18 mph21 mph23 mph23 mph22 mph13 mph16 mph14 mph
Twenty-foot wind max12 mph14 mph16 mph18 mph17 mph9 mph10 mph10 mph

Against the record

NOAA GHCN · Weslaco (TXW) · 11 mi away

Each forecast day against the same calendar date at the nearest long-record station: the 1991 to 2020 normal, and the record high and low with the year they were set.

DayForecastNormalRecord highRecord low
Sun Sep 2799° / 76°90° / 69°101° (2011)53° (1940)
Mon Sep 2899° / 77° would tie the record89° / 68°99° (1953)48° (1942)
Tue Sep 2999° / 79° would tie the record89° / 68°99° (1920)51° (1918)
Wed Sep 3099° / 80° would tie the record89° / 68°99° (1938)53° (1918)
Thu Oct 198° / 77°89° / 68°99° (1962)55° (1985)
Fri Oct 293° / 73°91° / 69°98° (1989)56° (1958)
Sat Oct 389° / 72°92° / 69°98° (1998)55° (1936)
Sun Oct 490° / 73°91° / 68°99° (2023)50° (1961)

Sun and moon

DayCivil twilightSunriseSunsetCivil twilightDaylightMoon
Sun6:59 AM7:22 AM7:22 PM7:45 PM12 h 0 min Waning gibbous · 99% lit
Mon6:59 AM7:22 AM7:21 PM7:44 PM11 h 59 min Waning gibbous · 95% lit
Tue7:00 AM7:23 AM7:20 PM7:43 PM11 h 57 min Waning gibbous · 90% lit
Wed7:00 AM7:23 AM7:19 PM7:42 PM11 h 56 min Waning gibbous · 82% lit
Thu7:01 AM7:24 AM7:18 PM7:41 PM11 h 54 min Waning gibbous · 73% lit
Fri7:01 AM7:24 AM7:17 PM7:40 PM11 h 53 min Waning gibbous · 64% lit
Sat7:02 AM7:25 AM7:16 PM7:39 PM11 h 51 min Last quarter · 53% lit
Sun7:02 AM7:25 AM7:14 PM7:37 PM11 h 49 min Last quarter · 43% lit

Forecast from the National Weather Service forecast grid at api.weather.gov, updated by the local office through the day; the written periods and hourly digest are the NWS’s own. Outlooks from the Storm Prediction Center, the Weather Prediction Center and the Climate Prediction Center via NOAA’s map services. Records and normals from NOAA’s Global Historical Climatology Network. Sun and moon computed here. Place names from GeoNames (CC BY 4.0).

What is here

Seven days
The high, the low, the chance and amount of rain and snow, the wind and the forecaster’s words for each day and night, from the National Weather Service grid for the exact cell your town sits in.
Hour by hour
Temperature, what it feels like, dew point, humidity, chance and amount of precipitation, wind and gusts, sky cover, the chance of thunder, pressure, visibility and ceiling, as a chart and as a table, with nights shaded.
Everything else on the grid
The office edits about sixty fields for every cell. The ones the mainstream forecast pages leave out are here as a daily table: HeatRisk, wet bulb globe temperature, lightning activity, mixing height, transport wind, the fire weather indices, and at the coast the waves and swell.
The discussion
The Area Forecast Discussion the forecaster wrote to explain the forecast, in their own words, with the specialist annexes folded away. Also the office’s hazardous weather outlook.
Beyond the week
The Storm Prediction Center’s severe weather category for each of the next eight days, the Weather Prediction Center’s rainfall forecast to day seven and its winter storm severity, and the Climate Prediction Center’s odds for days six to fourteen, all read at your coordinate.
Against the record
Each forecast day beside the same date at the nearest long-record station: the thirty-year normal and the record high and low with their years, so a forecast high that would break a record says so.
The next 90 days
The forecast as far as the grid, the National Blend and the global models reach, and the calendar after that: the normal and the record for every date, with the Climate Prediction Center’s lean for the weeks, the month and the season drawn over them. No made-up highs for a date three months out.

Common questions

Where does this forecast come from?

From the National Weather Service forecast grid published at api.weather.gov, the same grid the local forecast office edits through the day and the source of every forecast on weather.gov. The written periods, the hourly digest and the forecaster’s discussion are the NWS’s own products, shown as issued. Nothing here is a blend a website made.

How far ahead does it go?

The grid runs seven days ahead, hour by hour for the first days and in three to six hour steps after that. The National Blend of Models carries the days to eleven and the global models to sixteen. Beyond that the page carries the national centers’ outlooks, severe weather to day eight, rainfall to day seven, and the Climate Prediction Center’s odds for the coming weeks, month and season, over a ninety-day calendar of the normal and the record for each date. No forecast has skill day by day past about two weeks, and this page does not print one.

Why is this different from the app on my phone?

Most forecast apps show a blend of models chosen by the company that makes the app. This page shows the forecast the local National Weather Service office issues, edited by the forecasters who will also issue the warnings, and it shows all of it rather than the six numbers that fit on a phone. The discussion explains the reasoning, which no app carries.

What is a place’s address here?

Every town has its own page, such as /forecast/us/oklahoma/oklahoma-city/, and every day at a town has one too. A ZIP code typed into the search goes to the town it belongs to. Any coordinate at all can be looked up, and the page names the nearest town.

What the weather actually was · Open the live radar · Where the data comes from