diff --git a/client/src/components/EventTimeInput24h.tsx b/client/src/components/EventTimeInput24h.tsx
index c6ccafd..505a285 100644
--- a/client/src/components/EventTimeInput24h.tsx
+++ b/client/src/components/EventTimeInput24h.tsx
@@ -10,18 +10,23 @@ interface EventTimeInput24hProps {
   onChange: (value: string) => void
   disabled?: boolean
   'aria-label'?: string
+  fallback?: string
 }
 
 export default function EventTimeInput24h({
   value,
   onChange,
   disabled = false,
-  'aria-label': ariaLabel
+  'aria-label': ariaLabel,
+  fallback
 }: EventTimeInput24hProps) {
   const baseId = useId()
   const useNativePicker = preferNativeCameraPicker()
-  const { hours, minutes } = useMemo(() => splitTimeHHMM(value), [value])
-  const timeValue = useMemo(() => joinTimeHHMM(hours, minutes), [hours, minutes])
+  const { hours, minutes } = useMemo(() => splitTimeHHMM(value, fallback), [value, fallback])
+  const timeValue = useMemo(() => {
+    if (!value.trim()) return ''
+    return joinTimeHHMM(hours, minutes)
+  }, [value, hours, minutes])
 
   if (useNativePicker) {
     return (
@@ -34,7 +39,7 @@ export default function EventTimeInput24h({
           value={timeValue}
           onChange={(e) => {
             const next = e.target.value
-            if (next) onChange(next.slice(0, 5))
+            onChange(next ? next.slice(0, 5) : '')
           }}
           disabled={disabled}
           aria-label={ariaLabel}
diff --git a/client/src/components/LogEntryEditor.tsx b/client/src/components/LogEntryEditor.tsx
index 8914dd5..f787f4a 100644
--- a/client/src/components/LogEntryEditor.tsx
+++ b/client/src/components/LogEntryEditor.tsx
@@ -33,7 +33,7 @@ import {
   hasAnySignature
 } from '../utils/signatures.js'
 import type { SignatureValue } from '../types/signatures.js'
-import { buildLogEntryPayload, readLogEntryTides, sortLogEventsByTime, normalizeLogEvent, hasUnsavedEventDraft, currentLocalTimeHHMM, isValidTimeHHMM, type LogEventPayload } from '../utils/logEntryPayload.js'
+import { buildLogEntryPayload, readLogEntryTides, sortLogEventsByTime, normalizeLogEvent, hasUnsavedEventDraft, currentLocalTimeHHMM, isValidTimeHHMM, type LogEventPayload, type LogEntryTides } from '../utils/logEntryPayload.js'
 import EventTimeInput24h from './EventTimeInput24h.tsx'
 import CourseDialInput from './CourseDialInput.tsx'
 import { parseOwmCurrentWeather } from '../utils/openWeatherMap.js'
@@ -432,7 +432,7 @@ export default function LogEntryEditor({
     }
   }
 
-  const buildPayloadForSigning = useCallback((eventsOverride?: LogEvent[]) => {
+  const buildPayloadForSigning = useCallback((eventsOverride?: LogEvent[], tidesOverride?: LogEntryTides) => {
     return buildLogEntryPayload({
       date,
       dayOfTravel,
@@ -451,7 +451,7 @@ export default function LogEntryEditor({
         consumption: parseAppDecimalOrZero(fuelConsumption)
       },
       greywater: { level: parseAppDecimalOrZero(greywaterLevel) },
-      tides: { highWater: tideHighWater, lowWater: tideLowWater, ...tideLocation },
+      tides: tidesOverride ?? { highWater: tideHighWater, lowWater: tideLowWater, ...tideLocation },
       trackDistanceNm: parseOptionalFormDecimal(trackDistanceNm),
       trackSpeedMaxKn: parseOptionalFormDecimal(trackSpeedMaxKn),
       trackSpeedAvgKn: parseOptionalFormDecimal(trackSpeedAvgKn),
@@ -603,12 +603,14 @@ export default function LogEntryEditor({
       signCrew?: SignatureValue | ''
       aiSummary?: string
       aiSummaryGeneratedAt?: string
+      tidesOverride?: LogEntryTides
     }
   ) => {
     if (readOnly) return
 
     const normalized = Array.isArray(options) ? { eventsOverride: options } : (options ?? {})
     const eventsOverride = normalized.eventsOverride
+    const tidesOverride = normalized.tidesOverride
     const skipperToSave = normalized.signSkipper !== undefined ? normalized.signSkipper : signSkipper
     const crewToSave = normalized.signCrew !== undefined ? normalized.signCrew : signCrew
     let summaryToSave = normalized.aiSummary !== undefined ? normalized.aiSummary : aiSummary
@@ -636,7 +638,7 @@ export default function LogEntryEditor({
     }
 
     const entryData: Record<string, unknown> = {
-      ...buildPayloadForSigning(eventsOverride),
+      ...buildPayloadForSigning(eventsOverride, tidesOverride),
       signSkipper: normalizedSerializedSignature(skipperToSave),
       signCrew: normalizedSerializedSignature(crewToSave)
     }
@@ -1309,14 +1311,27 @@ export default function LogEntryEditor({
     }
   }
 
-  const applyTideFetchResult = (result: {
+  const applyTideFetchResult = async (result: {
     highWater: string
     lowWater: string
     location: TideLocationMeta
   }) => {
-    if (result.highWater) setTideHighWater(result.highWater)
-    if (result.lowWater) setTideLowWater(result.lowWater)
+    const nextTides = {
+      highWater: result.highWater,
+      lowWater: result.lowWater,
+      ...result.location
+    }
+    setTideHighWater(result.highWater)
+    setTideLowWater(result.lowWater)
     setTideLocation(result.location)
+
+    try {
+      await persistEntryToDb({ tidesOverride: nextTides })
+      trackPlausibleEvent(PlausibleEvents.TRAVEL_DAY_SAVED)
+    } catch (err) {
+      console.error('Failed to auto-save after tide fetch:', err)
+      showAlert(t('logs.tide_fetch_failed'), t('logs.tide_fetch_btn'))
+    }
   }
 
   const handleTideStationPick = async (pick: TideFetchNeedsStationPick, station: TideStation) => {
@@ -1330,7 +1345,7 @@ export default function LogEntryEditor({
         queryLng: pick.queryLng,
         analyticsSource: 'entry_editor'
       })
-      applyTideFetchResult(result)
+      await applyTideFetchResult(result)
       setTideStationPicker(null)
     } catch (err) {
       if (err instanceof TidesApiError && err.code === 'NO_DATA_FOR_DATE') {
@@ -1377,7 +1392,7 @@ export default function LogEntryEditor({
         return
       }
 
-      applyTideFetchResult(outcome as TideFetchResult)
+      await applyTideFetchResult(outcome as TideFetchResult)
     } catch (err) {
       if (err instanceof TidesApiError) {
         if (err.code === 'OFFLINE') {
@@ -2288,6 +2303,7 @@ export default function LogEntryEditor({
                     onChange={setTideHighWater}
                     disabled={readOnly || saving || tidesLoading}
                     aria-label={t('logs.tide_high_water')}
+                    fallback="00:00"
                   />
                 </div>
                 <div className="input-group">
@@ -2297,6 +2313,7 @@ export default function LogEntryEditor({
                     onChange={setTideLowWater}
                     disabled={readOnly || saving || tidesLoading}
                     aria-label={t('logs.tide_low_water')}
+                    fallback="00:00"
                   />
                 </div>
               </div>
diff --git a/client/src/utils/logEntryPayload.test.ts b/client/src/utils/logEntryPayload.test.ts
index cca7eba..262f796 100644
--- a/client/src/utils/logEntryPayload.test.ts
+++ b/client/src/utils/logEntryPayload.test.ts
@@ -5,6 +5,7 @@ import {
   isLogEventDraftEmpty,
   localDateString,
   normalizeLogEvent,
+  splitTimeHHMM,
   type LogEventPayload
 } from './logEntryPayload.js'
 
@@ -112,3 +113,25 @@ describe('buildLogEntryPayload tides', () => {
     })
   })
 })
+
+describe('splitTimeHHMM', () => {
+  it('splits valid time HH:MM correctly', () => {
+    const result = splitTimeHHMM('15:45')
+    expect(result).toEqual({ hours: '15', minutes: '45' })
+  })
+
+  it('uses fallback value when time is empty', () => {
+    const result = splitTimeHHMM('', '00:00')
+    expect(result).toEqual({ hours: '00', minutes: '00' })
+  })
+
+  it('falls back to current local time when empty and no fallback is specified', () => {
+    const result = splitTimeHHMM('')
+    const hours = parseInt(result.hours, 10)
+    const minutes = parseInt(result.minutes, 10)
+    expect(hours).toBeGreaterThanOrEqual(0)
+    expect(hours).toBeLessThanOrEqual(23)
+    expect(minutes).toBeGreaterThanOrEqual(0)
+    expect(minutes).toBeLessThanOrEqual(59)
+  })
+})
diff --git a/client/src/utils/logEntryPayload.ts b/client/src/utils/logEntryPayload.ts
index 12dc11e..3a0b489 100644
--- a/client/src/utils/logEntryPayload.ts
+++ b/client/src/utils/logEntryPayload.ts
@@ -72,8 +72,8 @@ export function isValidTimeHHMM(value: string): boolean {
   return parseTimeToHHMM(value) !== null
 }
 
-export function splitTimeHHMM(value: string): { hours: string; minutes: string } {
-  const parsed = parseTimeToHHMM(value) ?? currentLocalTimeHHMM()
+export function splitTimeHHMM(value: string, fallback?: string): { hours: string; minutes: string } {
+  const parsed = parseTimeToHHMM(value) ?? fallback ?? currentLocalTimeHHMM()
   return { hours: parsed.slice(0, 2), minutes: parsed.slice(3, 5) }
 }