San Marcos, Texas Weather Conditions

Severe Weather Alerts

National Weather Service:

Special Statement View All Alerts

Your Weather

To update your location please enter your ZIP code, city, state, airport code or country in the field below. Weather by E-mail: Forecast storm alerts. Weather E-Mail Alert Sign Up »

Current Conditions

  • 75°
  • Overcast
  • Wind: SSE 9 mph
  • Humidity: 78%
  • Visibility: 10.0 miles
  • Dew Point: 68°
  • Pressure: 29.78 in. +

Select a Section

Click a section below for more information.

Next 12 Hours

7  am
10  am
1  pm
4  pm
7  pm
Fog
Fog
Overcast
Overcast
Chance of a Thunderstorm
Chance of T-storms
Chance of a Thunderstorm
Chance of T-storms
Chance of a Thunderstorm
Chance of T-storms
72°
79°
88°
91°
73°
Forecast data from the National Digital Forecast Database.

5 Day Forecast

  • Tuesday
  • Chance of a Thunderstorm
  • High: 91 °
  • Low: 72 °
  • Chance of T-Storms
  • Wednesday
  • Partly Cloudy
  • High: 90 °
  • Low: 70 °
  • Partly Cloudy
  • Thursday
  • Partly Cloudy
  • High: 90 °
  • Low: 68 °
  • Partly Cloudy
  • Friday
  • Mostly Cloudy
  • High: 91 °
  • Low: 66 °
  • Mostly Cloudy
  • Saturday
  • Partly Cloudy
  • High: 95 °
  • Low: 64 °
  • Partly Cloudy

Forecast for San Marcos, Texas

Updated: 4:00 AM CDT on May 21, 2013

  • Tuesday

    Overcast in the morning, then mostly cloudy with a chance of a thunderstorm and a chance of rain. Fog early. High of 91F with a heat index of 97F. Breezy. Winds from the South at 15 to 20 mph. Chance of rain 40%.

  • Tuesday Night

    Mostly cloudy with a chance of a thunderstorm and a chance of rain. Low of 72F. Winds from the SE at 5 to 15 mph. Chance of rain 40%.

  • Wednesday

    Overcast in the morning, then partly cloudy. High of 90F. Winds from the SE at 5 to 10 mph.

  • Wednesday Night

    Clear in the evening, then mostly cloudy. Low of 70F. Winds from the SE at 5 to 15 mph.

  • Thursday

    Overcast in the morning, then partly cloudy. Fog early. High of 90F. Winds from the SSE at 5 to 15 mph.

  • Thursday Night

    Partly cloudy. Fog overnight. Low of 68F. Winds from the SSE at 5 to 15 mph.

  • Friday

    Mostly cloudy in the morning, then overcast. High of 91F. Winds from the SSE at 5 to 15 mph.

  • Friday Night

    Overcast with a chance of a thunderstorm and rain. Fog overnight. Low of 66F. Winds from the SSE at 5 to 10 mph.

  • Saturday

    Mostly cloudy. High of 95F. Winds from the SSE at 5 to 15 mph.

  • Saturday Night

    Partly cloudy. Fog overnight. Low of 64F. Winds from the SSE at 5 to 15 mph.

  • Sunday

    Partly cloudy. High of 93F. Winds from the SSE at 5 to 10 mph.

  • Sunday Night

    Clear. Fog overnight. Low of 59F. Winds from the SSE at 5 to 15 mph.

  • Monday

    Partly cloudy. High of 93F. Winds from the SSE at 5 to 10 mph.

  • Monday Night

    Partly cloudy. Low of 64F. Winds from the SSE at 5 to 15 mph.

  • Tuesday

    Partly cloudy. High of 91F. Winds from the SSE at 5 to 15 mph.

  • Tuesday Night

    Partly cloudy. Low of 70F. Winds from the SSE at 10 to 15 mph.

  • Wednesday

    Partly cloudy. High of 90F. Winds from the SSE at 5 to 15 mph.

  • Wednesday Night

    Mostly cloudy with a chance of rain. Low of 70F. Winds from the SSE at 10 to 15 mph. Chance of rain 40%.

  • Thursday

    Partly cloudy. High of 91F. Winds from the SSE at 5 to 15 mph.

  • Thursday Night

    Partly cloudy. Low of 70F. Winds from the SSE at 10 to 15 mph.

  • Friday

    Partly cloudy. High of 95F. Winds from the SSE at 5 to 10 mph.

  • Friday Night

    Clear. Fog overnight. Low of 70F. Winds from the SSE at 5 to 15 mph.

Severe Weather Alert Descriptions

 Special Statement  Statement as of 4:54 am CDT on May 21, 2013


... Extremely unstable airmass poised to erupt in severe thunderstorms
with large hail and damaging winds by late afternoon through this
evening...

Rich low level Gulf moisture coupled with steep lapse rates aloft
have resulted in an extremely unstable air-mass across south
central Texas early this morning. An upper level trough pushing
east over central Texas will slide a cold front into western
portions of south central Texas this afternoon. Scattered
thunderstorms will develop rapidly by late afternoon... quickly
becoming severe as the front encounters this unstable air mass.
The main threats will be from large hail and damaging thunderstorm
winds... however with the extreme instability present... isolated
tornadoes cannot be ruled out. Much of the eastern half of south
central Texas will be affected from late afternoon until the early
morning hours Wednesday. In addition... rainfall amounts may
average 1 to 3 inches within the heaviest storms producing some
localized flooding.

Heightened concern exists across the northeast corridor this
evening... including the cities of Burnet... Georgetown... Austin and
Giddings. Erosion of the capping inversion coupled with extreme
instability along the front and an increasing low level jet... may
lead to very large hail and isolated tornadoes.

The system should exit the region overnight tonight... early
Wednesday morning... with rains and severe weather ending from the
west.

Listen to NOAA Weather Radio or your local media for later updates
on this severe weather event. Also... go to weather.Gov/Austin for
the latest information... forecasts and warnings.



Personal Weather Stations

Personal Weather Stations [Add your weather station!]

Location: San Marcos - Country Estates, San Marcos, TX

Updated: 5:48 AM CDT

Temperature: 73.5 °F Dew Point: 72 °F Humidity: 95% Wind: ESE at 2.0 mph Pressure: 29.71 in Hourly Precipitation: 0.00 in Heat Index: 70 °F Graphs

Location: Hunter Ridge, San Marcos, TX

Updated: 5:48 AM CDT

Temperature: 73.6 °F Dew Point: 71 °F Humidity: 92% Wind: East at 1.0 mph Pressure: 29.74 in Hourly Precipitation: 0.00 in Heat Index: 71 °F Graphs

Location: Martindale, Martindale, TX

Updated: 5:48 AM CDT

Temperature: 75.4 °F Dew Point: 70 °F Humidity: 82% Wind: SE at 10.7 mph Pressure: 29.99 in Hourly Precipitation: 0.00 in Heat Index: 76 °F Graphs

Location: Williams Ranch, San Marcos, TX

Updated: 5:42 AM CDT

Temperature: 72.5 °F Dew Point: 71 °F Humidity: 94% Wind: SW at 6.0 mph Pressure: 29.36 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: Downtown, Staples, TX

Updated: 5:48 AM CDT

Temperature: 75.1 °F Dew Point: - Humidity: - Wind: SE at 7.0 mph Pressure: 29.76 in Hourly Precipitation: 0.00 in Heat Index: 73 °F Graphs

Location: paradise hills, Wimberley, TX

Updated: 5:48 AM CDT

Temperature: 72.3 °F Dew Point: 72 °F Humidity: 100% Wind: ENE at 4.9 mph Pressure: 28.41 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: ParkPlace4RV's, Canyon Lake, TX

Updated: 5:48 AM CDT

Temperature: 72.3 °F Dew Point: 70 °F Humidity: 94% Wind: SE at 5.0 mph Pressure: 29.71 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: APRSWXNET Wimberley TX US, Wimberley, TX

Updated: 5:15 AM CDT

Temperature: 72 °F Dew Point: 70 °F Humidity: 95% Wind: Calm Pressure: 29.78 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: MesoWest GOODWN TX US UPR, New Braunfels, TX

Updated: 4:10 AM CDT

Temperature: 75 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 73 °F Graphs

Location: Hilltop Ridge - The Summit, New Braunfels, TX

Updated: 5:47 AM CDT

Temperature: 72.7 °F Dew Point: 71 °F Humidity: 93% Wind: ESE at 7.0 mph Pressure: 29.71 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: River Road/Downtown Wimberley, Wimberley, TX

Updated: 5:45 AM CDT

Temperature: 74.7 °F Dew Point: 74 °F Humidity: 98% Wind: South at 5.3 mph Pressure: 29.70 in Hourly Precipitation: - Heat Index: 72 °F Graphs

Location: APRSWXNET Sattler TX US, Canyon Lake, TX

Updated: 5:13 AM CDT

Temperature: 74 °F Dew Point: 70 °F Humidity: 87% Wind: Calm Pressure: 29.67 in Hourly Precipitation: 0.00 in Heat Index: 73 °F Graphs

Location: Gruene Crossing, New Braunfels, TX

Updated: 5:48 AM CDT

Temperature: 72.7 °F Dew Point: 65 °F Humidity: 77% Wind: SE at 4.0 mph Pressure: 29.41 in Hourly Precipitation: 0.00 in Heat Index: 74 °F Graphs

Location: Preiss Heights, New Braunfels, TX

Updated: 5:49 AM CDT

Temperature: 73.4 °F Dew Point: 70 °F Humidity: 90% Wind: Calm Pressure: 29.68 in Hourly Precipitation: 0.00 in Heat Index: 71 °F Graphs

Location: Canyon Falls RV Park, Canyon Lake, TX

Updated: 5:49 AM CDT

Temperature: 74.3 °F Dew Point: 71 °F Humidity: 90% Wind: Calm Pressure: 29.68 in Hourly Precipitation: 0.00 in Heat Index: 73 °F Graphs

Location: Turnersville, Buda, TX

Updated: 5:49 AM CDT

Temperature: 73.5 °F Dew Point: 42 °F Humidity: 32% Wind: SSE at 19.0 mph Pressure: 29.69 in Hourly Precipitation: 0.00 in Heat Index: 77 °F Graphs

Location: Silverleaf, Canyon Park, Canyon Lake, TX

Updated: 5:48 AM CDT

Temperature: 73.5 °F Dew Point: 70 °F Humidity: 88% Wind: SE at 2.0 mph Pressure: 29.66 in Hourly Precipitation: 0.00 in Heat Index: 72 °F Graphs

Location: La Ventana, Driftwood, TX

Updated: 5:42 AM CDT

Temperature: 72.8 °F Dew Point: 70 °F Humidity: 90% Wind: SE at 4.0 mph Pressure: 29.68 in Hourly Precipitation: 0.00 in Heat Index: 70 °F Graphs

Location: Blanco River Estates, Wimberley, TX

Updated: 5:49 AM CDT

Temperature: 73.2 °F Dew Point: 70 °F Humidity: 89% Wind: Calm Pressure: 29.73 in Hourly Precipitation: 0.00 in Heat Index: 71 °F Graphs

Location: MesoWest NEWBRA TX US UPR, New Braunfels, TX

Updated: 3:45 AM CDT

Temperature: 75 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 73 °F Graphs

Location: Turkey Cove, Canyon Lake, TX

Updated: 5:42 AM CDT

Temperature: 73.5 °F Dew Point: 71 °F Humidity: 92% Wind: SSE at 6.0 mph Pressure: 29.71 in Hourly Precipitation: 0.00 in Heat Index: 71 °F Graphs

Location: Lake Dunlap, New Braunfels, TX

Updated: 5:48 AM CDT

Temperature: 74.8 °F Dew Point: 72 °F Humidity: 90% Wind: SE at 1.0 mph Pressure: 29.72 in Hourly Precipitation: 0.00 in Heat Index: 74 °F Graphs

Location: Goldenwood West, Austin, TX

Updated: 5:49 AM CDT

Temperature: 73.1 °F Dew Point: 69 °F Humidity: 86% Wind: SSE at 6.5 mph Pressure: 29.78 in Hourly Precipitation: 0.00 in Heat Index: 72 °F Graphs

Location: Vineyard Ridge, Driftwood, TX

Updated: 5:48 AM CDT

Temperature: 73.0 °F Dew Point: 26 °F Humidity: 17% Wind: South at 7.0 mph Pressure: 29.70 in Hourly Precipitation: 0.00 in Heat Index: 75 °F Graphs

Location: County Line Road Area, New Braunfels, TX

Updated: 5:49 AM CDT

Temperature: 73.5 °F Dew Point: 71 °F Humidity: 92% Wind: East at 4.6 mph Pressure: 29.74 in Hourly Precipitation: 0.00 in Heat Index: 71 °F Graphs

Location: Klein Rd Area, New Braunfels, TX

Updated: 5:45 AM CDT

Temperature: 72.9 °F Dew Point: 70 °F Humidity: 92% Wind: Calm Pressure: 29.54 in Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: Lazy B- Arroyo Doble Estates, Manchaca, TX

Updated: 5:43 AM CDT

Temperature: 74.1 °F Dew Point: 70 °F Humidity: 88% Wind: South at 1.7 mph Pressure: 29.67 in Hourly Precipitation: - Heat Index: 73 °F Graphs

Location: MesoWest KNBRYW TX US UPR, Seguin, TX

Updated: 4:40 AM CDT

Temperature: 74 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 72 °F Graphs

Location: Las Brisas, Seguin, TX

Updated: 5:49 AM CDT

Temperature: 73.4 °F Dew Point: 70 °F Humidity: 88% Wind: Calm Pressure: 29.75 in Hourly Precipitation: 0.00 in Heat Index: 72 °F Graphs

MSN Maps of:

Temp: Dew Point: Humidity Wind Pressure Hr Precip -

NWS Forecaster Discussion




Area forecast discussion 
National Weather Service Austin/San Antonio Texas 
316 am CDT Tuesday may 21 2013 


Short term (today through wednesday)... 
deep vortex over the Pacific northwest will dig southward and eject 
the downstream trough pushing over northwest Texas today. Extremely 
unstable air-mass in place over south central Texas with widespread 
3000-4000 j/kg MLCAPES expected this afternoon into tonight. The 
upper trough will push into central Texas this afternoon with an 
attendant cold front sliding into far western portions by early 
afternoon and slowly into The Hill Country by early evening. 
Initially...a strong cap may inhibit storms from forming along the 
front over far western portions this afternoon however as the upper 
trough digs a little further south across The Hill Country and 
northeast corridor towards evening...storms will be expected to 
back-build across central Texas into our area. An increasing low 
level jet over the eastern half of the region impinging the front 
will only worsen the severity. The main threats will be from large 
hail (and in some cases very large hail) and damaging thunderstorm 
winds from late afternoon to the early morning hours Wednesday. 


The main threat area per Storm Prediction Center will be generally across the eastern 
half of the region...but our analysis would give heightened 
concern from the eastern Hill Country through the northeast 
corridor...including the cities of Burnet...Georgetown...Austin 
and Giddings. This is because of the upper level cap...which 
according to sounding forecasts this evening...will have sufficiently 
eroded by the slight dig of the upper trough by the time of 
frontal passage. With the extreme amount of instability present... 
isolated tornadoes cannot be ruled out from developing super-cells 
across the eastern Hill Country through the northeast corridor 
late this afternoon through this evening. Rainfall of 1 to 3 
inches is possible as well across eastern portions of south 
central Texas this evening where the low level jet meets the 
front. 


Today though...morning clouds will decrease to partly cloudy this 
afternoon with a slight chance of showers and isolated thunderstorms 
Hill Country to the northeast corridor in a capped atmosphere. Highs 
today ranging from the upper 80s hills to the upper 90s Rio Grande 
plains. Tonight...as mentioned earlier...severe storms will 
back-build or develop across The Hill Country and spread 
southeastward over the remainder of south central Texas late this 
afternoon and during the evening...exiting the area during the early 
morning hours. Lows tonight low to middle 60s hills to middle 70s southern 
and eastern portions. On Wednesday west northwest flow aloft will 
bring in drier air while a subtropical ridge begins developing 
north over the area. Decreasing cloudiness becoming partly cloudy 
Wednesday afternoon with highs near 90 or low 90s over much of the 
region except middle to upper 90s over south central portions and the 
Rio Grande plains. 


&& 


Long term (wednesday night through monday)... 
the subtropical ridge will continue building across south and 
central Texas Wednesday night and Thursday but with a continued 
southeast flow off the Gulf...morning clouds are expected becoming 
partly cloudy by Thursday afternoon. This will likely remain the 
overall weather pattern Friday through the early part of next week 
as the subtropical ridge remains dominant. As the ridge builds 
aloft...weaker southeast winds may allow for temperatures to cool 
more overnight (to near seasonal) while highs will remain a few 
degrees above normal each day Friday through Monday. A few weak 
waves on the backside of the ridge may help develop Burro Mountain 
development over northern Mexico Friday through Sunday but 
uncertainties whether or not they will reach our area will result 
in silent 10 probability of precipitation each day. 


&& 


Preliminary point temps/pops... 
Austin Camp Mabry 92 70 92 71 94 / 20 40 - - - 
Austin Bergstrom international Airport 91 69 91 69 92 / 20 40 - - - 
New Braunfels Muni Airport 92 70 92 69 93 / 10 40 - - - 
Burnet Muni Airport 88 66 90 68 91 / 20 30 0 - - 
del Rio International Airport 99 72 98 75 98 / 10 20 - - - 
Georgetown Muni Airport 88 68 88 69 91 / 20 40 - - - 
Hondo Muni Airport 95 70 95 71 96 / 10 30 - - - 
San Marcos Muni Airport 90 71 90 70 91 / 20 40 - - - 
La Grange - Fayette regional 91 75 92 73 92 / 10 40 10 - - 
San Antonio International Airport 92 71 93 72 93 / 10 30 - - - 
Stinson Muni Airport 92 71 92 71 93 / 10 30 - - - 


&& 


Ewx watches/warnings/advisories...none. 
&& 


$$ 


Mesoscale/aviation...13 
synoptic/grids...02 










National Weather Service Glossary of Abbreviations

Non-Expanded Version (with abbreviations)

Powered by the Weather Underground, Inc.