A fixed edition with explicit coverage
This edition preserves the source bundle retrieved 2026-09-28T15:53:53.748Z. The lake section covers only the September dates listed below, not a completed calendar month. The tide section looks forward from its own dated prediction window. Neither section is a causal analysis or a safety assessment.
Lake changes over the available dates
| TWDB lake | Available dates | Elevation change | Conservation-full change |
|---|---|---|---|
| Lake Travis | 2026-09-01–2026-09-28 28 of 30 calendar dates | -3.63 ft | -5.9 percentage points |
| Canyon Lake | 2026-09-01–2026-09-28 28 of 30 calendar dates | -1.19 ft | -2.1 percentage points |
| Lake Corpus Christi | 2026-09-01–2026-09-28 28 of 30 calendar dates | -0.91 ft | -6.6 percentage points |
Each change subtracts the first available daily-history reading from the last within September. Percentage points are a difference between two percent-full values, not a relative percentage change. Missing dates are not interpolated. The current headline reading on a lake page may use a different date or time summary.
Lake Travis: the retained daily observations
View the dated readings (elevation in feet)
| Date | Elevation (ft) |
|---|---|
| 2026-09-01 | 678.38 |
| 2026-09-02 | 678.24 |
| 2026-09-03 | 678.08 |
| 2026-09-04 | 677.93 |
| 2026-09-05 | 677.78 |
| 2026-09-06 | 677.63 |
| 2026-09-07 | 677.49 |
| 2026-09-08 | 677.34 |
| 2026-09-09 | 677.21 |
| 2026-09-10 | 677.07 |
| 2026-09-11 | 676.94 |
| 2026-09-12 | 676.80 |
| 2026-09-13 | 676.68 |
| 2026-09-14 | 676.56 |
| 2026-09-15 | 676.43 |
| 2026-09-16 | 676.28 |
| 2026-09-17 | 676.13 |
| 2026-09-18 | 675.99 |
| 2026-09-19 | 675.86 |
| 2026-09-20 | 675.71 |
| 2026-09-21 | 675.57 |
| 2026-09-22 | 675.43 |
| 2026-09-23 | 675.31 |
| 2026-09-24 | 675.18 |
| 2026-09-25 | 675.08 |
| 2026-09-26 | 674.95 |
| 2026-09-27 | 674.83 |
| 2026-09-28 | 674.75 |
Canyon Lake: the retained daily observations
View the dated readings (elevation in feet)
| Date | Elevation (ft) |
|---|---|
| 2026-09-01 | 909.22 |
| 2026-09-02 | 909.19 |
| 2026-09-03 | 909.13 |
| 2026-09-04 | 909.09 |
| 2026-09-05 | 909.05 |
| 2026-09-06 | 909.01 |
| 2026-09-07 | 908.98 |
| 2026-09-08 | 908.93 |
| 2026-09-09 | 908.88 |
| 2026-09-10 | 908.83 |
| 2026-09-11 | 908.79 |
| 2026-09-12 | 908.75 |
| 2026-09-13 | 908.70 |
| 2026-09-14 | 908.65 |
| 2026-09-15 | 908.59 |
| 2026-09-16 | 908.55 |
| 2026-09-17 | 908.49 |
| 2026-09-18 | 908.45 |
| 2026-09-19 | 908.42 |
| 2026-09-20 | 908.37 |
| 2026-09-21 | 908.32 |
| 2026-09-22 | 908.27 |
| 2026-09-23 | 908.22 |
| 2026-09-24 | 908.18 |
| 2026-09-25 | 908.15 |
| 2026-09-26 | 908.10 |
| 2026-09-27 | 908.05 |
| 2026-09-28 | 908.03 |
Lake Corpus Christi: the retained daily observations
View the dated readings (elevation in feet)
| Date | Elevation (ft) |
|---|---|
| 2026-09-01 | 92.57 |
| 2026-09-02 | 92.52 |
| 2026-09-03 | 92.48 |
| 2026-09-04 | 92.45 |
| 2026-09-05 | 92.43 |
| 2026-09-06 | 92.40 |
| 2026-09-07 | 92.37 |
| 2026-09-08 | 92.33 |
| 2026-09-09 | 92.31 |
| 2026-09-10 | 92.27 |
| 2026-09-11 | 92.21 |
| 2026-09-12 | 92.16 |
| 2026-09-13 | 92.14 |
| 2026-09-14 | 92.10 |
| 2026-09-15 | 92.06 |
| 2026-09-16 | 92.04 |
| 2026-09-17 | 92.04 |
| 2026-09-18 | 92.03 |
| 2026-09-19 | 92.01 |
| 2026-09-20 | 91.98 |
| 2026-09-21 | 91.93 |
| 2026-09-22 | 91.87 |
| 2026-09-23 | 91.82 |
| 2026-09-24 | 91.79 |
| 2026-09-25 | 91.75 |
| 2026-09-26 | 91.72 |
| 2026-09-27 | 91.69 |
| 2026-09-28 | 91.66 |
Tides: know the window before comparing heights
These astronomical predictions are an outlook retained with this edition. They are not September observations. The extrema below span each full listed window, rather than a single day’s tidal range.
| Reference station | Local-date window | Predicted extrema, ft MLLW |
|---|---|---|
| North Jetty, Tillamook Bay NOAA 9437585 | 2026-09-28–2026-10-07 39 high/low events | -0.92 to 8.61 NOAA source ↗ |
| Bogue Inlet NOAA TEC2837 | 2026-09-28–2026-10-07 38 high/low events | 0.02 to 3.03 NOAA source ↗ |
| Charleston (Customhouse Wharf) NOAA 8665530 | 2026-09-28–2026-10-07 38 high/low events | 0.15 to 6.58 NOAA source ↗ |
| Oak Island, Yaupon Beach NOAA 8659182 | 2026-09-28–2026-10-07 38 high/low events | -0.02 to 5.97 NOAA source ↗ |
| Galveston Pleasure Pier NOAA 8771510 | 2026-09-28–2026-10-07 26 high/low events | -0.05 to 2.77 NOAA source ↗ |
| San Diego NOAA 9410170 | 2026-09-28–2026-10-07 38 high/low events | -0.14 to 6.50 NOAA source ↗ |
| Bowen Point, Shallotte Inlet NOAA 8659665 | 2026-09-28–2026-10-07 38 high/low events | -0.04 to 5.56 NOAA source ↗ |
MLLW is a station reference. These heights do not rank beach safety, available water depth or storm-surge risk. Use the current planner and NOAA for planning; this archived outlook will not roll forward.
Open the evidence
Download, reproduce and cite
This permanent edition retains the exact normalized records used above. Daily refreshes do not replace it. The lake observations cover a partial month; the tide file contains predictions for its stated outlook window.
Method, file integrity and reuse
Method monthly-v1 subtracts the first retained lake reading from the last; it does not fill missing dates. Tide extrema use the full retained prediction window. These files retain normalized records, not original agency response bytes.
Download the standalone calculation method and snapshot into one folder, then run node method.mjs snapshot.json with Node.js. Its output must match the calculated-results JSON. The SHA-256 manifest records file sizes and checksums; see the bundle readme for instructions and limitations. Checksums detect file changes; they do not certify agency accuracy.
Underlying agency sources retain their applicable terms. Cite Public Atlas for this compilation and derived calculation, and credit the issuing sources listed in the snapshot. Report corrections through our corrections process; corrected editions must preserve the original version.
Suggested citation
Public Atlas Editorial. (2026-09-28). September notebook: lake changes and the next tide window. Edition v1; method monthly-v1. https://www.publicatlasdata.com/notes/2026-09/. Coverage: Partial September observations; upcoming tide predictions. Human editorial review pending.
Edition history and corrections
Download the complete frozen source snapshot (JSON), including retained lake readings and tide predictions. This snapshot stays separate from daily refreshes. Report a concern through our corrections process.
Published 2026-09-28. First edition. Independent human review pending. Next source and editorial review target: 2026-10-28. Future monthly runs prepare data drafts for review; they do not silently publish interpretations.
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