WaterloggedRiver Cruise Watch

The river's logbook for cruise travellers

See the map Daily sailing schedule 14-day weather forecast

Your sailing

River Duchess · Rhine Holiday Markets

Uniworld Boutique River Cruises · departs Wednesday 16 December 2026 · Cologne → Basel · 8 days

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Register for the Daily River Log Watch for this sailing

Latest readings: Wednesday 16 September 2026. Water levels change daily. Check again closer to your departure.

The Daily River Watch

Wednesday 16 September 2026

River levels this morning — not the levels expected on your sailing dates

Rain check: almost no rain is forecast anywhere on your route over the next fourteen days. The forecast reaches 29 September. It does not change any status on this page.

What the statuses mean — each one is measured against the level we estimate this ship needs

  • Far below the line The measured level is under half of Waterlogged's reference line for this ship.
  • Below the line The measured level is below Waterlogged's reference line for this ship. It is not yet under half that level.
  • Above the line The measured level is at or above Waterlogged's reference line for this ship.
  • Lock-controlled Locks hold the level on this stretch, so low water rarely stops a ship here. High water, maintenance, closures, restrictions on the locks and the cruise line's own decision can still affect a day.
  • No line published The reading is real. Nobody publishes a level for this stretch to measure it against.
    No reading yet We include this location on your daily schedule but there is no data available.
  • No gauge on this stretch We watch no gauge on this stretch of river. There is no reading for the day and no line to measure one against. We are not telling you the water is fine, and we are not telling you anything holds it at a working level — those are things we have not established here.
  • In port The ship is in port on this day. Our record holds no river transit for it, so there is no stretch of river to read. That is what we hold, not a claim about where the ship goes.
  • Not sailing The ship does not sail on this day. Your itinerary spends it on land, so there is no river level to read and no low-water question to answer.

A gauge level is not the depth of the navigable channel, not the room under your ship's keel, and not your ship's draft. The rain forecast further down uses one more status of its own, temporarily unavailable, when that feed is missing or out of date.

The official forward outlook

Waterlogged does not provide its own independent future river depth forecast. We show today's gauge reading and compare them with our own reference lines and other historic data. Where Waterlogged has received licenses, it includes river forecasts and clearly identifies the sources where they are from. Waterlogged provides direct links to the gauge forecasts from national providers. BfG has given us permission to show their six week forecasts.

Your daily sailing schedule

Below are the ports you travel to and the depth of the water, as of today's date, and how much water is needed for your ship to sail. A graph shows the median or normal river depth.

Two words will help. A A riverside station that measures the water level in centimetres against a fixed zero point. is a riverside station that measures water level. Your ship's How deep a ship sits in the water. That depth sets how much water it needs underneath. is how deep it sits in the water. This affects how much water it needs below the hull.

Day1–2

Cologne

Wed 16 – Thu 17 December · Germany

In port

The ship is in port on this day. Our record holds no river transit for it, so there is no stretch of river to read.

The ship is in port on this day.

Full details

Our record holds no river transit for this day, so there is no stretch of river being read for it and no water level that applies to it.

Where the ship isin port
River transit on recordnone for this day
Level readingnone applies — no stretch of river is being read

This says what our record holds, not what the ship does. We are not telling you it stays alongside, and we have not worked out whether locks hold any water near this city, so we do not say either. On the days this route is on the river, the readings above and below say so.

Day3

Koblenz

Friday 18 December · Germany

Far below the line

The measured level is under half of Waterlogged's reference line for this ship.

Scale 0–250 cm

65 cm below Waterlogged’s reference line

That is how far today's measured level sits below the line we estimate this ship needs. The level it is measured against is our own estimate, not a figure from the cruise line.

Water level now (16 September) 28 cm
How we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. 93 cm
Normal for 18 December (median for 2015–2026) 191 cm

Rising — the river level rose 1 cm in the last three days.

On the record: For 2015–2025, we checked the eleven days around this date. Kaub’s lowest daily average was 73 cm, in 2016. Today’s reading is 28. That is below every one of the 121 readings in that window.

Water levels are measured at the Kaub gauge – German federal waterways gauge service (PEGELONLINE).

TODAY2000WLSNWLSN1 Sep1 Oct1 Nov1 Dec
  • Current level
  • Past average for this date
  • WLSNHow we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. (93 cm)
  • Measured level below that line
  • BfG’s own 14-day forecast: their low-to-high range and middle line · BfG issued this forecast: 2026-09-15 GMT+1 · Bundesanstalt für Gewässerkunde (BfG)

Current and normal water levels. The solid blue line shows the current measured water level. The dashed grey line is the historic average of the water level from August 8th until December 11th. The bold dashed line labelled WLSN is the water level the ship needs — Waterlogged's reference line for this ship: 93 cm. It is a gauge level, not a depth under the hull. Today's water sits 113 cm below the normal water level for this date. The water level at this location historically keeps rising over the next three months.

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub BfG issued this forecast: 2026-09-15 GMT+1
BfG's 14-day water-level forecast for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-15 GMT+1.

400Wed 16 SepMon 28 Sep
BfG's own daily figures for Kaub, in cm at the gauge.
DayLowerMiddleUpper
Wed 16 Sep313437
Thu 17 Sep273134
Fri 18 Sep192328
Sat 19 Sep131925
Sun 20 Sep142129
Mon 21 Sep152434
Tue 22 Sep152536
Wed 23 Sep132233
Thu 24 Sep102031
Fri 25 Sep71831
Sat 26 Sep41630
Sun 27 Sep21430
Mon 28 Sep01330

BfG publishes a low and a high figure for every day, not one certain number. Read the whole range.

The three columns are BfG's own 10th, 50th and 90th percentiles, in centimetres at the gauge. Nothing between them is filled in by us.

BfG does not publish values above 640 centimetres. Where a figure would be higher, their file says so and this table reads "above 640".

BfG's own file for Kaub (opens in a new tab)

BfG's 6-week outlook for Kaub BfG issued this forecast: 2026-09-14
BfG's 6-week outlook for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-14.

Each line is one whole week, which is how BfG publishes this product. It gives no figure for any single day, and neither do we.

BfG's own weekly figures for Kaub, in cm at the gauge.
WeekLowerMiddleUpper
14–20 September192532
21–27 September22246
28 Sep–4 Oct-142787
5–11 October-1037107
12–18 October-1148140
19–25 October-363162

The three columns are BfG's own 5th, 50th and 95th percentiles from their weather-driven runs, in centimetres at the gauge.

BfG's own file for Kaub (opens in a new tab)

Forecast water levels are from BfG. Waterlogged only reports historical and current data.

Every figure above is a water level at the gauge, in centimetres. It is not the depth of water under a ship and it is not a ship's draft.

Day4

Rüdesheim; Mainz

Saturday 19 December · Switzerland

Far below the line

The measured level is under half of Waterlogged's reference line for this ship.

Scale 0–250 cm

65 cm below Waterlogged’s reference line

That is how far today's measured level sits below the line we estimate this ship needs. The level it is measured against is our own estimate, not a figure from the cruise line.

Water level now (16 September) 28 cm
How we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. 93 cm
Normal for 19 December (median for 2015–2026) 188 cm

Rising — the river level rose 1 cm in the last three days.

On the record: For 2015–2025, we checked the eleven days around this date. Kaub’s lowest daily average was 73 cm, in 2016. Today’s reading is 28. That is below every one of the 121 readings in that window.

Water levels are measured at the Kaub gauge – German federal waterways gauge service (PEGELONLINE).

TODAY2000WLSNWLSN1 Sep1 Oct1 Nov1 Dec
  • Current level
  • Past average for this date
  • WLSNHow we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. (93 cm)
  • Measured level below that line
  • BfG’s own 14-day forecast: their low-to-high range and middle line · BfG issued this forecast: 2026-09-15 GMT+1 · Bundesanstalt für Gewässerkunde (BfG)

Current and normal water levels. The solid blue line shows the current measured water level. The dashed grey line is the historic average of the water level from August 8th until December 11th. The bold dashed line labelled WLSN is the water level the ship needs — Waterlogged's reference line for this ship: 93 cm. It is a gauge level, not a depth under the hull. Today's water sits 113 cm below the normal water level for this date. The water level at this location historically keeps rising over the next three months.

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub BfG issued this forecast: 2026-09-15 GMT+1
BfG's 14-day water-level forecast for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-15 GMT+1.

400Wed 16 SepMon 28 Sep
BfG's own daily figures for Kaub, in cm at the gauge.
DayLowerMiddleUpper
Wed 16 Sep313437
Thu 17 Sep273134
Fri 18 Sep192328
Sat 19 Sep131925
Sun 20 Sep142129
Mon 21 Sep152434
Tue 22 Sep152536
Wed 23 Sep132233
Thu 24 Sep102031
Fri 25 Sep71831
Sat 26 Sep41630
Sun 27 Sep21430
Mon 28 Sep01330

BfG publishes a low and a high figure for every day, not one certain number. Read the whole range.

The three columns are BfG's own 10th, 50th and 90th percentiles, in centimetres at the gauge. Nothing between them is filled in by us.

BfG does not publish values above 640 centimetres. Where a figure would be higher, their file says so and this table reads "above 640".

BfG's own file for Kaub (opens in a new tab)

BfG's 6-week outlook for Kaub BfG issued this forecast: 2026-09-14
BfG's 6-week outlook for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-14.

Each line is one whole week, which is how BfG publishes this product. It gives no figure for any single day, and neither do we.

BfG's own weekly figures for Kaub, in cm at the gauge.
WeekLowerMiddleUpper
14–20 September192532
21–27 September22246
28 Sep–4 Oct-142787
5–11 October-1037107
12–18 October-1148140
19–25 October-363162

The three columns are BfG's own 5th, 50th and 95th percentiles from their weather-driven runs, in centimetres at the gauge.

BfG's own file for Kaub (opens in a new tab)

Forecast water levels are from BfG. Waterlogged only reports historical and current data.

Every figure above is a water level at the gauge, in centimetres. It is not the depth of water under a ship and it is not a ship's draft.

Day5

Germersheim

Sunday 20 December · Switzerland

No line published

This is a real reading. There is nothing published to measure it against.

Scale 0–450 cm

312 cm
measured

Nobody publishes a target level for this stretch, so there is nothing to measure the reading against. We show the reading and the direction, and nothing more.

Water level now (16 September) 312 cm

Falling — the river level fell 8 cm in the last three days.

Water levels are measured at the Maxau gauge – German federal waterways gauge service (PEGELONLINE).
No official data — the reading is official; there is simply nothing published to compare it against.

We do not draw a measured history graph for this gauge. The reading above is current and official; the archive the graph would be drawn from is not ours to republish.

The official forecast for this gauge

BfG publishes no 14-day forecast for this gauge.

BfG's 6-week outlook for Maxau BfG issued this forecast: 2026-09-14
BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-14.

Each line is one whole week, which is how BfG publishes this product. It gives no figure for any single day, and neither do we.

BfG's own weekly figures for Maxau, in cm at the gauge.
WeekLowerMiddleUpper
14–20 September299311322
21–27 September276310347
28 Sep–4 Oct256320396
5–11 October273336410
12–18 October285348423
19–25 October307366439

The three columns are BfG's own 5th, 50th and 95th percentiles from their weather-driven runs, in centimetres at the gauge.

BfG's own file for Maxau (opens in a new tab)

Forecast water levels are from BfG. Waterlogged only reports historical and current data.

Every figure above is a water level at the gauge, in centimetres. It is not the depth of water under a ship and it is not a ship's draft.

Day6

Strasbourg

Monday 21 December · France

No line published

This is a real reading. There is nothing published to measure it against.

Scale 0–450 cm

312 cm
measured

Nobody publishes a target level for this stretch, so there is nothing to measure the reading against. We show the reading and the direction, and nothing more.

Water level now (16 September) 312 cm

Falling — the river level fell 8 cm in the last three days.

Water levels are measured at the Maxau gauge – German federal waterways gauge service (PEGELONLINE).
No official data — the reading is official; there is simply nothing published to compare it against.

We do not draw a measured history graph for this gauge. The reading above is current and official; the archive the graph would be drawn from is not ours to republish.

The official forecast for this gauge

BfG publishes no 14-day forecast for this gauge.

BfG's 6-week outlook for Maxau BfG issued this forecast: 2026-09-14
BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-14.

Each line is one whole week, which is how BfG publishes this product. It gives no figure for any single day, and neither do we.

BfG's own weekly figures for Maxau, in cm at the gauge.
WeekLowerMiddleUpper
14–20 September299311322
21–27 September276310347
28 Sep–4 Oct256320396
5–11 October273336410
12–18 October285348423
19–25 October307366439

The three columns are BfG's own 5th, 50th and 95th percentiles from their weather-driven runs, in centimetres at the gauge.

BfG's own file for Maxau (opens in a new tab)

Forecast water levels are from BfG. Waterlogged only reports historical and current data.

Every figure above is a water level at the gauge, in centimetres. It is not the depth of water under a ship and it is not a ship's draft.

Day7–8

Basel

Tue 22 – Wed 23 December · Switzerland

No line published

This is a real reading. There is nothing published to measure it against.

Scale 0–450 cm

312 cm
measured

Nobody publishes a target level for this stretch, so there is nothing to measure the reading against. We show the reading and the direction, and nothing more.

Water level now (16 September) 312 cm

Falling — the river level fell 8 cm in the last three days.

Water levels are measured at the Maxau gauge – German federal waterways gauge service (PEGELONLINE).
No official data — the reading is official; there is simply nothing published to compare it against.

We do not draw a measured history graph for this gauge. The reading above is current and official; the archive the graph would be drawn from is not ours to republish.

The official forecast for this gauge

BfG publishes no 14-day forecast for this gauge.

BfG's 6-week outlook for Maxau BfG issued this forecast: 2026-09-14
BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-14.

Each line is one whole week, which is how BfG publishes this product. It gives no figure for any single day, and neither do we.

BfG's own weekly figures for Maxau, in cm at the gauge.
WeekLowerMiddleUpper
14–20 September299311322
21–27 September276310347
28 Sep–4 Oct256320396
5–11 October273336410
12–18 October285348423
19–25 October307366439

The three columns are BfG's own 5th, 50th and 95th percentiles from their weather-driven runs, in centimetres at the gauge.

BfG's own file for Maxau (opens in a new tab)

Forecast water levels are from BfG. Waterlogged only reports historical and current data.

Every figure above is a water level at the gauge, in centimetres. It is not the depth of water under a ship and it is not a ship's draft.

Rain on your route — calculated daily

Rain forecast by Open-Meteo (commercial licence) · fetched 16 September 2026 at 05:16 UTC · covering 14 days, 16 September to 29 September.

Rain can raise the water level of a river but there is no fixed rule on how much it does. We only report how much the quantity of rainfall has changed the water level before under similar conditions. It is context, not a prediction of a river level.

Licensed rain forecast + what the water level has actually done before

The detailed weather forecast for your route

All rain forecasts use the same scale, 0–12 mm of rain a day, so you can compare them directly. Each column is one day, with its date at the top, then the sky for that day and the daily high in °C.

Rain forecast by Open-Meteo (commercial licence) · fetched 16 September 2026 at 05:16 UTC · covering 14 days, 16 September to 29 September.

Kaub Rhine · Germany

Far below the line

date, sky and daily high °C

16 September29 September

14 days · mm/day upstream of this gauge

≈ 3 mm expected upstream over 14 days

Rain forecast by Open-Meteo (commercial licence) · fetched 16 September 2026 at 05:16 UTC · covering 14 days, 16 September to 29 September.

Almost no rain is forecast above this gauge over the next fourteen days. In past years a dry fortnight left the water level to keep doing what it was already doing. It never brought the level up to 93.

This is our reading of the rain forecast, based on what rain has actually done to this river in past years. It is not an official river forecast.

The rest of your route

That is why none of these has a rain forecast. What is left is the weather for your day in town.

CologneGermany

date, sky and daily high °C

the same days · 16 September to 29 September · daily highs in °C

Rain forecast by Open-Meteo (commercial licence) · fetched 16 September 2026 at 05:16 UTC · covering 14 days, 16 September to 29 September.

How rain reaches the river — the rules we use the stages, the half-lives and the 2003 warning behind every line above

How rain becomes a water level

A river responds to rain in stages. A nearby shower may matter less than rain far upstream.

  • Rain fallsWhere the rain lands matters as much as the total.
  • Ground takes a shareDry ground can hold most of the first rain.
  • Tributaries bring it downWater arrives from different Side rivers and streams that feed the main river at different times. at different times.
  • The gauge gets a pulseA A short rise that has travelled downstream after rain further up the river. can briefly raise the level at the gauge.
  • Baseflow settles itThe slow supply of stored water that keeps a river running between periods of rain. is the slower supply of stored water. It decides where the level settles.

Why winter rain often does more

Winter ground is usually wetter and cooler. Plants use less water then. Less water also evaporates. More of the same rain can reach the river. In high summer, dry soil and growing plants take more water first. Less water then flows over the land into the river.

What "half-life" means here

The How long half of an unusual water-level difference has historically taken to fade. is based on past records. It is the time for half the extra height above the usual seasonal level to fade. It describes persistence, not how many centimetres a storm will add.

Estimated half-life of unusual levels at eligible route gauges
GaugeWinter-runoff blockSummer-recession block
Pfelling 17.3 daysdrift_params.json → PFELLING.blocks[winter_runoff].half_life_days 15.6 daysdrift_params.json → PFELLING.blocks[summer_recession].half_life_days
Hofkirchen 20.2 daysdrift_params.json → HOFKIRCHEN.blocks[winter_runoff].half_life_days 18.7 daysdrift_params.json → HOFKIRCHEN.blocks[summer_recession].half_life_days
Kaub 32.7 daysdrift_params.json → KAUB.blocks[winter_runoff].half_life_days 55.3 daysdrift_params.json → KAUB.blocks[summer_recession].half_life_days
Cologne 31.1 daysdrift_params.json → KOELN.blocks[winter_runoff].half_life_days 58.0 daysdrift_params.json → KOELN.blocks[summer_recession].half_life_days

Read the difference carefully. A longer summer value at the Rhine gauges does not mean summer rain adds more water. It means an unusual measured level faded more slowly in that set of calendar dates. The block names come from the parameter file; they are not weather seasons or a rain-to-level formula.

Rules of thumb

Use these to read a wet outlook — not to predict a sailing-day level.

  1. After a long dry period, the first roughly 10 mm may mainly soak the soil. Do not expect much change at the gauge before that.

    Source: waterlogged/rain_explainer.py → transfer_function.soil_absorption_first_mm.value_mm = 10; explicitly qualitative, not a fitted gauge coefficient.

  2. Look downstream after about 1 day Basel–Maxau, 1–1½ days Maxau–Kaub and ½–1 day Kaub–Cologne; Austrian Danube events spanned 60–118 hours, so there is no honest fixed Danube clock.

    Sources: docs/council_alignment/lens_hydrology.md gives Rhine flood-wave and falling-water travel times. docs/climate_evidence_wide_signals.md gives the "Travel time & Alpine share" event range and the no-fixed-lag rule.

  3. A routed rain pulse can briefly raise a gauge. Baseflow is the slower supply of stored water. It decides where the level settles.

    Source: waterlogged/rain_explainer.py gives the wording about a rain pulse in each season. The figures in the table above are the fitted half_life_days from drift_params.json.

That is the calculation you have just read. The licence turns this panel from a list of links into a daily reading. It still stops where the evidence stops.

Rainfall forecast is provided by a commercial forecast service. Waterlogged reports on how an amount of rainfall has historically affected the water level. This historical information is provided for illustrative reasons and should not be used for any prediction.

Rain is context, not a prediction of a river level. Nothing on this page turns millimetres of rain into centimetres at a gauge, and no status anywhere on this page moves because rain is forecast.

The official services we link to forecast the water level at a gauge. That is not a promised depth of water under your ship, and none of them publishes one.

Weather data comes from a licensed provider. Weather data by Open-Meteo (commercial licence)

How to read every number on this page

The numbers on this page stay free.

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If you want us to read this sailing every morning and send it to your inbox, the Daily River Log Watch is free for your sailing. Nothing to pay, nothing renews. The last morning is the morning after you leave the ship.

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Every morning until the morning after you leave the ship: the reading on the gauge that governs your stretch, what changed overnight, and the river companion — the story of the water you are sailing on. Free.

Keep my email for this sailing only, so Waterlogged can send me the Daily River Log Watch for it each morning, free, until the morning after the sailing ends. No marketing and no sale of my address. Stop any time by replying stop, or delete my address on request; it is deleted no later than 180 days after the scheduled sailing. Privacy details: /privacy.

Do not see your sailing? We do not report cancelled sailings. Tell us which sailing we are missing and we will add it. You can also email info@rivercruisewatch.com with the cruise line, the ship and the dates.

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Day 3 · Koblenz

Open the official projection.

Your call here is 93 days away — beyond the daily forecast

BfG six-week outlook for Kaub — likely ranges for each week
Published by Bundesanstalt für Gewässerkunde (BfG).

Nothing published today can tell you the level on 18 December. Germany's federal hydrology institute. It publishes the official water-level forecasts and outlooks.'s daily forecast only reaches fourteen days ahead. Your call here is 93 days away. We have picked the product that does reach it, so you do not have to.

That product is BfG's six-week outlook. It is not a daily prediction. It shows likely ranges for each week. Each range is where that week's level is expected to fall, with the odds attached. The ranges come from many past-weather what-if runs, not from a single-line prediction.

The button below opens Kaub's own sheet directly. Find the week beginning 14 December. Then read which band it sits in against the How we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. line on this page.

From 4 December, this port will be fourteen days away. The daily forecast will then reach your date, and this block will switch itself over to it.

How to read it

The official document is in German. Both choices below explain the same product.

BfG's own FAQ on the six-week bands (PDF, German)
English guide (unofficial)

English guide (unofficial) — only the German original is official.

What this document is. BfG runs the river model many times over. Each run uses a different possible weather sequence taken from the historical record. The chart shades in the spread of those runs. It answers "where is this gauge likely to sit", not "what will it read on Thursday".

How the chart is laid out. Time runs left to right in weeks, not days. The upright scale is centimetres at Kaub's own The fixed zero point for a gauge's centimetre scale. It can sit above the riverbed.. This page uses the same scale, so 93 cm means the same thing on both.

What the shaded bands mean. Each band covers a share of those model runs. A wide band means the runs disagree and the week is genuinely open. A narrow band means they agree. The band is the answer — the middle of it is not a prediction.

What to do with it. Find the week beginning 14 December. If the whole band sits below 93 cm, the outlook for your week is uniformly short. If 93 cm falls inside the band, the honest answer is that nobody knows yet. If the whole band sits above 93 cm, the outlook is comfortable — which still is not a promise about your afternoon.

What it cannot do. It cannot tell you a date, it cannot tell you whether your cruise line will sail, and a weekly average can hide days that sit well below it.

Written by Waterlogged in our own words to explain how the official product works. It is not a translation of it, it has no authority, and where the two differ the German original governs.

Open that FAQ in Google Translate ↗ Machine translation (unofficial) — only the German original is official.

We checked the direct links on 3–4 August 2026 (docs/bfg_deep_links.md). Waterlogged never re-dates or re-scores the authority's product. Where BfG has given us permission to show their figures, they are on this page above, under BfG's name and with BfG's own issue stamp; everything else here is a link to the authority's page.

Day 4 · Rüdesheim; Mainz

Open the official projection.

Your call here is 94 days away — beyond the daily forecast

BfG six-week outlook for Kaub — likely ranges for each week
Published by Bundesanstalt für Gewässerkunde (BfG).

Nothing published today can tell you the level on 19 December. Germany's federal hydrology institute. It publishes the official water-level forecasts and outlooks.'s daily forecast only reaches fourteen days ahead. Your call here is 94 days away. We have picked the product that does reach it, so you do not have to.

That product is BfG's six-week outlook. It is not a daily prediction. It shows likely ranges for each week. Each range is where that week's level is expected to fall, with the odds attached. The ranges come from many past-weather what-if runs, not from a single-line prediction.

The button below opens Kaub's own sheet directly. Find the week beginning 14 December. Then read which band it sits in against the How we calculate ship needWaterlogged estimates that a river needs to be 2.05m in depth to be navigable by river cruises. A river cruise ship has a draft of approximately 1.60m and we add an additional 0.45m above this. This number is not from official cruise line reports. Ships with smaller drafts or special permission may be able to sail in less water. The figure on the page beside this note is a gauge level, and a gauge level is the height of the water at one measuring station, read from that station's own zero. It is not the depth of the navigable channel, it is not the room left under a ship's keel, and it is not a ship's draft. Our line is a level we compare today's reading with. It is not a depth anybody has measured under your ship. line on this page.

From 5 December, this port will be fourteen days away. The daily forecast will then reach your date, and this block will switch itself over to it.

How to read it

The official document is in German. Both choices below explain the same product.

BfG's own FAQ on the six-week bands (PDF, German)
English guide (unofficial)

English guide (unofficial) — only the German original is official.

What this document is. BfG runs the river model many times over. Each run uses a different possible weather sequence taken from the historical record. The chart shades in the spread of those runs. It answers "where is this gauge likely to sit", not "what will it read on Thursday".

How the chart is laid out. Time runs left to right in weeks, not days. The upright scale is centimetres at Kaub's own The fixed zero point for a gauge's centimetre scale. It can sit above the riverbed.. This page uses the same scale, so 93 cm means the same thing on both.

What the shaded bands mean. Each band covers a share of those model runs. A wide band means the runs disagree and the week is genuinely open. A narrow band means they agree. The band is the answer — the middle of it is not a prediction.

What to do with it. Find the week beginning 14 December. If the whole band sits below 93 cm, the outlook for your week is uniformly short. If 93 cm falls inside the band, the honest answer is that nobody knows yet. If the whole band sits above 93 cm, the outlook is comfortable — which still is not a promise about your afternoon.

What it cannot do. It cannot tell you a date, it cannot tell you whether your cruise line will sail, and a weekly average can hide days that sit well below it.

Written by Waterlogged in our own words to explain how the official product works. It is not a translation of it, it has no authority, and where the two differ the German original governs.

Open that FAQ in Google Translate ↗ Machine translation (unofficial) — only the German original is official.

We checked the direct links on 3–4 August 2026 (docs/bfg_deep_links.md). Waterlogged never re-dates or re-scores the authority's product. Where BfG has given us permission to show their figures, they are on this page above, under BfG's name and with BfG's own issue stamp; everything else here is a link to the authority's page.

Day 5 · Germersheim

Open the official projection.

Your call here is 95 days away — beyond the daily forecast

BfG six-week outlook for Maxau — likely ranges for each week
Published by Bundesanstalt für Gewässerkunde (BfG).

Nothing published today can tell you the level on 20 December. Germany's federal hydrology institute. It publishes the official water-level forecasts and outlooks.'s daily forecast only reaches fourteen days ahead. Your call here is 95 days away. We have picked the product that does reach it, so you do not have to.

That product is BfG's six-week outlook. It is not a daily prediction. It shows likely ranges for each week. Each range is where that week's level is expected to fall, with the odds attached. The ranges come from many past-weather what-if runs, not from a single-line prediction.

The button below opens Maxau's own sheet directly. Find the week beginning 14 December.

From 6 December, this port will be fourteen days away. The daily forecast will then reach your date, and this block will switch itself over to it.

How to read it

The official document is in German. Both choices below explain the same product.

BfG's own FAQ on the six-week bands (PDF, German)
English guide (unofficial)

English guide (unofficial) — only the German original is official.

What this document is. BfG runs the river model many times over. Each run uses a different possible weather sequence taken from the historical record. The chart shades in the spread of those runs. It answers "where is this gauge likely to sit", not "what will it read on Thursday".

How the chart is laid out. Time runs left to right in weeks, not days. The upright scale is centimetres at Maxau's own The fixed zero point for a gauge's centimetre scale. It can sit above the riverbed..

What the shaded bands mean. Each band covers a share of those model runs. A wide band means the runs disagree and the week is genuinely open. A narrow band means they agree. The band is the answer — the middle of it is not a prediction.

What to do with it. Find the week beginning 14 December and read the whole band rather than the middle of it.

What it cannot do. It cannot tell you a date, it cannot tell you whether your cruise line will sail, and a weekly average can hide days that sit well below it.

Written by Waterlogged in our own words to explain how the official product works. It is not a translation of it, it has no authority, and where the two differ the German original governs.

Open that FAQ in Google Translate ↗ Machine translation (unofficial) — only the German original is official.

We checked the direct links on 3–4 August 2026 (docs/bfg_deep_links.md). Waterlogged never re-dates or re-scores the authority's product. Where BfG has given us permission to show their figures, they are on this page above, under BfG's name and with BfG's own issue stamp; everything else here is a link to the authority's page.

Day 6 · Strasbourg

Open the official projection.

Your call here is 96 days away — beyond the daily forecast

BfG six-week outlook for Maxau — likely ranges for each week
Published by Bundesanstalt für Gewässerkunde (BfG).

Nothing published today can tell you the level on 21 December. Germany's federal hydrology institute. It publishes the official water-level forecasts and outlooks.'s daily forecast only reaches fourteen days ahead. Your call here is 96 days away. We have picked the product that does reach it, so you do not have to.

That product is BfG's six-week outlook. It is not a daily prediction. It shows likely ranges for each week. Each range is where that week's level is expected to fall, with the odds attached. The ranges come from many past-weather what-if runs, not from a single-line prediction.

The button below opens Maxau's own sheet directly. Find the week beginning 21 December.

From 7 December, this port will be fourteen days away. The daily forecast will then reach your date, and this block will switch itself over to it.

How to read it

The official document is in German. Both choices below explain the same product.

BfG's own FAQ on the six-week bands (PDF, German)
English guide (unofficial)

English guide (unofficial) — only the German original is official.

What this document is. BfG runs the river model many times over. Each run uses a different possible weather sequence taken from the historical record. The chart shades in the spread of those runs. It answers "where is this gauge likely to sit", not "what will it read on Thursday".

How the chart is laid out. Time runs left to right in weeks, not days. The upright scale is centimetres at Maxau's own The fixed zero point for a gauge's centimetre scale. It can sit above the riverbed..

What the shaded bands mean. Each band covers a share of those model runs. A wide band means the runs disagree and the week is genuinely open. A narrow band means they agree. The band is the answer — the middle of it is not a prediction.

What to do with it. Find the week beginning 21 December and read the whole band rather than the middle of it.

What it cannot do. It cannot tell you a date, it cannot tell you whether your cruise line will sail, and a weekly average can hide days that sit well below it.

Written by Waterlogged in our own words to explain how the official product works. It is not a translation of it, it has no authority, and where the two differ the German original governs.

Open that FAQ in Google Translate ↗ Machine translation (unofficial) — only the German original is official.

We checked the direct links on 3–4 August 2026 (docs/bfg_deep_links.md). Waterlogged never re-dates or re-scores the authority's product. Where BfG has given us permission to show their figures, they are on this page above, under BfG's name and with BfG's own issue stamp; everything else here is a link to the authority's page.

Day 7–8 · Basel

Open the official projection.

Your call here is 97 days away — beyond the daily forecast

BfG six-week outlook for Maxau — likely ranges for each week
Published by Bundesanstalt für Gewässerkunde (BfG).

Nothing published today can tell you the level on 22 December. Germany's federal hydrology institute. It publishes the official water-level forecasts and outlooks.'s daily forecast only reaches fourteen days ahead. Your call here is 97 days away. We have picked the product that does reach it, so you do not have to.

That product is BfG's six-week outlook. It is not a daily prediction. It shows likely ranges for each week. Each range is where that week's level is expected to fall, with the odds attached. The ranges come from many past-weather what-if runs, not from a single-line prediction.

The button below opens Maxau's own sheet directly. Find the week beginning 21 December.

From 8 December, this port will be fourteen days away. The daily forecast will then reach your date, and this block will switch itself over to it.

How to read it

The official document is in German. Both choices below explain the same product.

BfG's own FAQ on the six-week bands (PDF, German)
English guide (unofficial)

English guide (unofficial) — only the German original is official.

What this document is. BfG runs the river model many times over. Each run uses a different possible weather sequence taken from the historical record. The chart shades in the spread of those runs. It answers "where is this gauge likely to sit", not "what will it read on Thursday".

How the chart is laid out. Time runs left to right in weeks, not days. The upright scale is centimetres at Maxau's own The fixed zero point for a gauge's centimetre scale. It can sit above the riverbed..

What the shaded bands mean. Each band covers a share of those model runs. A wide band means the runs disagree and the week is genuinely open. A narrow band means they agree. The band is the answer — the middle of it is not a prediction.

What to do with it. Find the week beginning 21 December and read the whole band rather than the middle of it.

What it cannot do. It cannot tell you a date, it cannot tell you whether your cruise line will sail, and a weekly average can hide days that sit well below it.

Written by Waterlogged in our own words to explain how the official product works. It is not a translation of it, it has no authority, and where the two differ the German original governs.

Open that FAQ in Google Translate ↗ Machine translation (unofficial) — only the German original is official.

We checked the direct links on 3–4 August 2026 (docs/bfg_deep_links.md). Waterlogged never re-dates or re-scores the authority's product. Where BfG has given us permission to show their figures, they are on this page above, under BfG's name and with BfG's own issue stamp; everything else here is a link to the authority's page.