Thursday, August17, 2017 L-36.com


Marine Weather and Tides
Sunset Valley, TX

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 6:58AMSunset 8:10PM Thursday August 17, 2017 2:09 PM CDT (19:09 UTC) Moonrise 1:41AMMoonset 3:46PM Illumination 21% Phase: Waning Crescent; Moon at 25 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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7 Day Forecast for Marine Location Near Sunset Valley, TX
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location: 30.21, -97.8     debug


Area Discussion for - Austin/San Antonio, TX
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Fxus64 kewx 171757
afdewx
area forecast discussion
national weather service austin san antonio tx
1257 pm cdt Thu aug 17 2017

Aviation 18z_tafs
ceilings have lifted toVFR at all sites with south or southeast
10-15 knot winds expected this afternoon. A few models are showing
that convection may be possible this afternoon and early evening
north of aus, but decreasing moisture and increasing stability should
prevent this from occurring. Winds will stay up around 10-15 knots
tonight before decreasing to 5-10 knots overnight with MVFR ceilings
developing by 9z at Sat ssf. Confidence in MVFR ceilings is lower at
aus where winds may be more s-sw than the s-se winds Sat ssf should
have, but we included them after 11z at aus for now. Regardless,VFR
conditions should return to the i-35 sites between 14-15z.

Prev discussion issued 1023 am cdt Thu aug 17 2017
update...

low temperatures and overnight dewpoints were higher than expected
which should lead to slightly higher values of moisture this
afternoon. In addition, southwest winds at the surface may lead to
higher high temperatures as well today. Upped high temps and
dewpoints across the eastern counties and this should lead to heat
advisory criteria being exceeded in the far eastern counties. Went
ahead and issued a heat advisory for lee, fayette, lavaca, gonzales,
and dewitt county.

Prev discussion... Issued 617 am cdt Thu aug 17 2017
update...

12z aviation update below.

Aviation...

MVFR ceilings in stratus continues early this morning along the
escarpment edge into portions of the hill country. This includes
sat ssf and at times aus. There is a chance the stratus may develop
into drt around or after 12z but lower confidence in this.VFR
conditions redevelop 15z-17z as stratus mixes out. Generally shras
and tstms should stay north and west of the area and TAF sites today.

Prev discussion... Issued 350 am cdt Thu aug 17 2017
short term (today through Friday)...

high pressure aloft remains dominant over most of south central tx,
with some subtle instability hanging on over parts of the edwards
plateau into NRN mexico early this morning. A tropical moisture axis
and weak mid-level cyclonic shear over this region has allowed for a
few elevated overnight showers generally north of rocksprings and
west of del rio. Satellite imagery loops depicting mid level clouds
and rapid refresh models would suggest some cyclonic shear rooted
over the serranias del burros will extend into swrn parts of val
verde county to allow for continued weak elevated convection into the
daytime.

The mid level ridge axis over central tx will both strengthen and
build northward today and tonight, leading to reduced surface winds
in the late afternoon and evening over the next couple days. While
the trend for very gradual lowering of day-to-day heat indices should
continue through afternoon mixing and lack of rainfall, triple digit
heat index values remain in the picture. Those spending several
hours outdoors in the afternoon and evening along and east of i-35
may not sense the slight improvement due to the lighter winds from
the seabreeze. Will continue show the elevated heat indices in the
sps hwo.

Long term (Friday night through Wednesday)...

the mid-level ridge axis remains entrenched over central tx over the
weekend, with the orientation tilting as heights build nwd over the
srn rockies Saturday. By Monday, a pacific upper low erodes this wrn
build-up again and a tutt low over the gulf pinches off the eastern
edge of the ridge axis. In the center, the upper ridge remains
dominant over tx with only subtle changes in the surface winds
expected early next week versus this weekend.

Some deterministic data anticipates a surge in pwat values to
generate rain chances, but knowing subsidence enhancement precedes
the approach of a tutt from the east, the drier GFS looks most
probable. None of the above mentioned mid upper level pattern shifts
should put a significant dent in the triple digit heat and or heat
indices through at least Tuesday.

Model diverge a bit on the broader mid-level pattern on Wednesday
with the GFS showing an inverted trough over S tx left from the
weakening tutt and the ecm depicting potential instability arriving
from the north after a westward shift of the ridge aloft. Will give
in to a generic isolated rain chance for Wednesday for all areas as
either of these solutions seem plausible.

Preliminary point temps pops
Austin camp mabry 77 100 77 100 76 10 0 0 - 10
austin bergstrom intl airport 76 99 76 100 75 10 0 0 - 10
new braunfels muni airport 75 99 75 100 75 - 0 0 - 10
burnet muni airport 74 98 74 98 74 10 0 0 - -
del rio intl airport 78 99 78 101 78 0 - 0 - 0
georgetown muni airport 76 98 75 98 75 10 0 0 - 10
hondo muni airport 75 100 74 101 74 0 0 0 0 -
san marcos muni airport 76 99 75 100 75 10 0 0 - 10
la grange - fayette regional 77 99 76 100 76 10 - 0 10 10
san antonio intl airport 76 99 76 99 76 0 0 0 0 10
stinson muni airport 76 101 76 101 76 0 0 0 0 10

Ewx watches warnings advisories
Heat advisory until 7 pm cdt this evening for the following
counties: de witt... Fayette... Gonzales... Lavaca... Lee.

Mesoscale aviation... Lh
synoptic grids... Hampshire
public service data collection... 30


Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Austin-Bergstrom International Airport, TX7 mi77 minS 13 G 1810.00 miPartly Cloudy94°F71°F48%1015.5 hPa
Austin City, Austin Camp Mabry, TX8 mi79 minS 7 G 1710.00 miFair96°F70°F43%1015.6 hPa
Austin Executive Airport, TX18 mi75 minS 9 G 1410.00 miFair91°F71°F52%1017.3 hPa
Lago Vista TX, Rusty Allen Airport, TX22 mi75 minS 9 G 1410.00 miFair92°F70°F49%1018.3 hPa
San Marcos, San Marcos Municipal Airport, TX22 mi75 minS 1110.00 miFair93°F71°F50%1030 hPa

Wind History from AUS (wind in knots)
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Last 24hrS15
G20
S16
G19
S11SE11S9S14S14S14
G20
S11S11S9S8S11S10SW6S5S7S8S10S10S10S14
G17
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1 day agoS13
G17
S11
G19
SE13S8S12
G19
SE12S10S11S12S10S10S12S11S12
G18
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G24
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G21
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S8
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2 days agoS11S11
G15
S10S7S9
G18
SE8S9S14S8S14S10S8S7S10S8S6S6S8S11S13
G23
S14S11
G16
S12
G18
S11
G16

Tide / Current Tables for
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Tide / Current Tables for
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Weather Map and Satellite Images
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Weather Map
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IR Satellite Image from GEOS
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GOES Local Image of SouthCentralPlains    EDIT
Geos

Wind Forecast for Austin/San Antonio, TX (15,3,4,5)
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Ground Weather Radar Station Central Texas
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.