diff --git a/CHANGELOG.md b/CHANGELOG.md
index a79441fa2..9091c9283 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,7 +24,19 @@
   the five borough cores load and `CCTV_NYC_MAX_SOURCES` changes the cap. The catalog-wide ceiling is
   unchanged; extra cameras share it round-robin with the other packs.
 
-- Cancelled catalog queries refuse execution when their signal is already aborted.
+- Street Level counts unique tiles before ranking so overlapping dateline halves
+  in polar views do not waste slots in the 16-tile overview budget.
+
+- Directions no longer shows a truncation notice for a route with exactly 200
+  turns, and a roundabout at the 200th turn keeps its exit distance.
+
+- Weather records keep missing conditions unknown and refuse summaries without a measured temperature.
+
+- Tool string length validation counts Unicode characters correctly, including characters outside the basic multilingual plane.
+
+- Director timeline seeks cross the dateline along the short longitude arc.
+
+- Reject impossible FIRMS acquisition calendar days in the CSV parser before trailing-24-hour filtering.
 
 - Treat explicitly current, complete empty vessel coverage as a successful update,
   clearing obsolete contacts while retaining stale or incomplete snapshots.
diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index bd346b4f5..dbf5e9b05 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -1467,7 +1467,7 @@ accessible name remains "Don't show this again". Control behavior is unchanged.
 
 ## FIRMS source status
 
-FIRMS ingestion and adaptation require explicit finite coordinates within WGS84 ranges; genuine zero coordinates remain valid and admitted detection indices stay sequential.
+The FIRMS CSV parser rejects impossible acquisition calendar dates before the proxy filters records to the trailing 24 hours, while retaining valid UTC acquisition times.
 
 The FIRMS proxy records source success after appending its rows. If aggregation
 throws, that source reports failure without a contradictory success entry.
diff --git a/src/data/firms-calendar-validity.test.mjs b/src/data/firms-calendar-validity.test.mjs
new file mode 100644
index 000000000..1ccaf7435
--- /dev/null
+++ b/src/data/firms-calendar-validity.test.mjs
@@ -0,0 +1,23 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { acquisitionMsUtc } from './firmsCsv.js';
+test('FIRMS acquisition dates cannot roll into a different calendar day', () => {
+  for (const [date, time] of [
+    ['2026-02-30', '1200'],
+    ['2026-04-31', '1200'],
+    ['2026-13-01', '1200'],
+    ['2026-07-16junk', '1200'],
+    ['2026-07-16', '2400'],
+    ['2026-07-16', '1260'],
+    ['2026-07-16', null],
+    ['2026-07-16', ''],
+  ]) {
+    assert.ok(Number.isNaN(acquisitionMsUtc(date, time)), `${date}:${time}`);
+  }
+  for (const [date, time, expected] of [
+    ['2024-02-29', '45', Date.UTC(2024, 1, 29, 0, 45)],
+    ['2026-07-16', '0', Date.UTC(2026, 6, 16)],
+  ]) {
+    assert.equal(acquisitionMsUtc(date, time), expected);
+  }
+});
diff --git a/src/data/firmsCsv.js b/src/data/firmsCsv.js
index aafeac50b..368ef4f73 100644
--- a/src/data/firmsCsv.js
+++ b/src/data/firmsCsv.js
@@ -163,7 +163,13 @@ export function acquisitionMsUtc(acqDate, acqTime) {
     minutes > 59
   )
     return NaN;
-  return Date.UTC(year, month - 1, day, hours, minutes);
+  const ms = Date.UTC(year, month - 1, day, hours, minutes);
+  const parsed = new Date(ms);
+  return parsed.getUTCFullYear() === year &&
+    parsed.getUTCMonth() === month - 1 &&
+    parsed.getUTCDate() === day
+    ? ms
+    : NaN;
 }
 
 /**