Viking Herja, Basel → Trier, 12 September — The Daily River Watch

The Daily River Watch

Monday 7 September 2026

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

Rain check: about 16 mm of rain is forecast above Kaub over fourteen days. The forecast reaches 20 September. It does not change any status on this page.

2ports far below the line
0ports below the line
0ports above the line
0ports on lock-controlled reaches
5ports with no line to compare
0ports on stretches we watch no gauge on
0ports with no river transit recorded
3ports where the ship is not sailing

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 The rain forecast further down uses one more status of its own, temporarily unavailable, when that feed is missing or out of date.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 is a riverside station that measures water level. Your ship's is how deep it sits in the water. This affects how much water it needs below the hull.

Day1–2

Zürich

Sat 12 – Sun 13 September

Not sailing

The ship does not sail on this day. Your itinerary spends it on land, so no river level applies to it.

The ship does not sail on this day.

Full details

Your itinerary spends this day on land. The ship is not sailing, so there is no stretch of river under it and no water level that applies to it.

What the ship does	it does not sail on this day
Level reading	none applies — no river is being sailed
Sensitive to low water	not at all, on this day

Waterlogged reads river levels, and this day has none to read. What happens on it is a question for your cruise line's own schedule, not for the water.

Day3

Basel

Monday 14 September · Switzerland

No line published

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

Scale 0–450 cm

321 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 (7 September)	321 cm

Falling — the river level fell 7 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: 2026-09-03

BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	300	310	320
10–16 September	283	326	371
17–23 September	267	354	472
24–30 September	281	360	465
1–7 October	308	373	458
8–14 October	324	385	465

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.

Official forecast: Baden-Württemberg's own forecast for Maxau

Published by Hochwasservorhersagezentrale Baden-Württemberg der LUBW.

BfG does not forecast Maxau. Its daily fourteen-day product covers seven Rhine gauges further downstream, and Maxau is not one of them. The service that does forecast this gauge is Baden-Württemberg's own flood forecast centre, and ELWIS sends you there too.

On that page choose the Vorhersage tab. A solid line runs about two days ahead in centimetres. After that the chart switches to a wider trend estimate with a shaded band around it and a no-rain scenario, reaching roughly a fortnight.

Nothing on that page reaches 14 September yet. The forecast line stops about two days out, and the trend estimate past it is a range, not a date. Come back nearer the day.

Whichever line you read, it is the authority's, not ours. Waterlogged reports measured levels and the record behind them, and publishes no forward level of its own.

https://www.hvz.baden-wuerttemberg.de/pegel.html?id=09016

Day4

Strasbourg

Tuesday 15 September · France

No line published

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

Scale 0–450 cm

321 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 (7 September)	321 cm

Falling — the river level fell 7 cm in the last three days.

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: 2026-09-03

BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	300	310	320
10–16 September	283	326	371
17–23 September	267	354	472
24–30 September	281	360	465
1–7 October	308	373	458
8–14 October	324	385	465

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.

Official forecast: Baden-Württemberg's own forecast for Maxau

Published by Hochwasservorhersagezentrale Baden-Württemberg der LUBW.

Nothing on that page reaches 15 September yet. The forecast line stops about two days out, and the trend estimate past it is a range, not a date. Come back nearer the day.

Whichever line you read, it is the authority's, not ours. Waterlogged reports measured levels and the record behind them, and publishes no forward level of its own.

https://www.hvz.baden-wuerttemberg.de/pegel.html?id=09016

Day5

Speyer

Wednesday 16 September · Germany

No line published

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

Scale 0–450 cm

321 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 (7 September)	321 cm

Falling — the river level fell 7 cm in the last three days.

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: 2026-09-03

BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	300	310	320
10–16 September	283	326	371
17–23 September	267	354	472
24–30 September	281	360	465
1–7 October	308	373	458
8–14 October	324	385	465

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.

Official forecast: Baden-Württemberg's own forecast for Maxau

Published by Hochwasservorhersagezentrale Baden-Württemberg der LUBW.

Nothing on that page reaches 16 September yet. The forecast line stops about two days out, and the trend estimate past it is a range, not a date. Come back nearer the day.

Whichever line you read, it is the authority's, not ours. Waterlogged reports measured levels and the record behind them, and publishes no forward level of its own.

https://www.hvz.baden-wuerttemberg.de/pegel.html?id=09016

Day6

Mainz

Thursday 17 September · Germany

No line published

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

Scale 0–450 cm

321 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 (7 September)	321 cm

Falling — the river level fell 7 cm in the last three days.

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: 2026-09-03

BfG's 6-week outlook for Maxau

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	300	310	320
10–16 September	283	326	371
17–23 September	267	354	472
24–30 September	281	360	465
1–7 October	308	373	458
8–14 October	324	385	465

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.

Official forecast: Baden-Württemberg's own forecast for Maxau

Published by Hochwasservorhersagezentrale Baden-Württemberg der LUBW.

Nothing on that page reaches 17 September yet. The forecast line stops about two days out, and the trend estimate past it is a range, not a date. Come back nearer the day.

Whichever line you read, it is the authority's, not ours. Waterlogged reports measured levels and the record behind them, and publishes no forward level of its own.

https://www.hvz.baden-wuerttemberg.de/pegel.html?id=09016

Day7

Koblenz

Friday 18 September · Germany

Far below the line

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

Scale 0–200 cm

62 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 (7 September)	31 cm
	93 cm
Normal for 18 September (median for 2015–2026)	139 cm

Falling — the river level fell 7 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 61 cm, in 2018. Today’s reading is 31. 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).

Current level
Past average for this date
WLSN — (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: 2026-09-06 GMT+1 · Bundesanstalt für Gewässerkunde (BfG)
BfG’s own 6-week outlook: one block for each whole published week · 3 of 4 published weeks reach beyond the scale of this frame and are not drawn · BfG issued this forecast: 2026-09-03 · Bundesanstalt für Gewässerkunde (BfG)

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub BfG issued this forecast: 2026-09-06 GMT+1

BfG's 14-day water-level forecast for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-06 GMT+1.

BfG's own daily figures for Kaub, in cm at the gauge.
Day	Lower	Middle	Upper
Mon 7 Sep	30	32	35
Tue 8 Sep	29	33	37
Wed 9 Sep	27	32	38
Thu 10 Sep	25	32	39
Fri 11 Sep	27	36	45
Sat 12 Sep	34	46	59
Sun 13 Sep	37	51	67
Mon 14 Sep	37	52	69
Tue 15 Sep	36	50	68
Wed 16 Sep	32	47	64
Thu 17 Sep	27	42	60
Fri 18 Sep	22	38	58
Sat 19 Sep	20	37	59

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: 2026-09-03

BfG's 6-week outlook for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	30	37	44
10–16 September	7	29	55
17–23 September	-6	51	135
24–30 September	-9	57	159
1–7 October	-3	67	173
8–14 October	6	74	170

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.

Official forecast: BfG 14-day forecast for Kaub, via ELWIS

Published by Bundesanstalt für Gewässerkunde (BfG), published through ELWIS.

Your call here is now inside the daily forecast's fourteen-day horizon. So this block has switched itself from the six-week bands to the daily product.

The button below opens Kaub's own forecast page directly. Read across to 18 September. Remember the number .

BfG publishes a range, not a single line — that spread is their own honest uncertainty. Read the whole of it.

https://www.elwis.de/DE/dynamisch/Wasserstaende/Pegelvorhersage:KAUB

Day8

Cochem

Saturday 19 September · Germany

Far below the line

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

Scale 0–200 cm

62 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 (7 September)	31 cm
	93 cm
Normal for 19 September (median for 2015–2026)	139 cm

Falling — the river level fell 7 cm in the last three days.

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

Current level
Past average for this date
WLSN — (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: 2026-09-06 GMT+1 · Bundesanstalt für Gewässerkunde (BfG)
BfG’s own 6-week outlook: one block for each whole published week · 3 of 4 published weeks reach beyond the scale of this frame and are not drawn · BfG issued this forecast: 2026-09-03 · Bundesanstalt für Gewässerkunde (BfG)

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub BfG issued this forecast: 2026-09-06 GMT+1

BfG's 14-day water-level forecast for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-06 GMT+1.

BfG's own daily figures for Kaub, in cm at the gauge.
Day	Lower	Middle	Upper
Mon 7 Sep	30	32	35
Tue 8 Sep	29	33	37
Wed 9 Sep	27	32	38
Thu 10 Sep	25	32	39
Fri 11 Sep	27	36	45
Sat 12 Sep	34	46	59
Sun 13 Sep	37	51	67
Mon 14 Sep	37	52	69
Tue 15 Sep	36	50	68
Wed 16 Sep	32	47	64
Thu 17 Sep	27	42	60
Fri 18 Sep	22	38	58
Sat 19 Sep	20	37	59

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: 2026-09-03

BfG's 6-week outlook for Kaub

Published by Bundesanstalt für Gewässerkunde (BfG). BfG issued this forecast: 2026-09-03.

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.
Week	Lower	Middle	Upper
3–9 September	30	37	44
10–16 September	7	29	55
17–23 September	-6	51	135
24–30 September	-9	57	159
1–7 October	-3	67	173
8–14 October	6	74	170

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.

Official forecast: BfG 14-day forecast for Kaub, via ELWIS

Published by Bundesanstalt für Gewässerkunde (BfG), published through ELWIS.

Your call here is now inside the daily forecast's fourteen-day horizon. So this block has switched itself from the six-week bands to the daily product.

The button below opens Kaub's own forecast page directly. Read across to 19 September. Remember the number .

BfG publishes a range, not a single line — that spread is their own honest uncertainty. Read the whole of it.

https://www.elwis.de/DE/dynamisch/Wasserstaende/Pegelvorhersage:KAUB

Day9

Bernkastel; Trier

Sunday 20 September · France

No line published

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

Scale 0–350 cm

219 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 (7 September)	219 cm
Normal for 20 September (median for 2000–2026)	223 cm

Rising — the river level rose 9 cm in the last three days.

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

Current level
Past average for this date
Measured level below that line

Official forecast: Rhineland-Palatinate flood forecast centre — Cochem

Published by Hochwasservorhersagezentrale Rheinland-Pfalz.

No German federal forecast covers the Moselle. The state flood forecast centre for Rhineland-Palatinate is the one service that forecasts this gauge, and the button below opens Cochem's own page there.

Its own notice says a Cochem forecast is only possible above 241 cm, because weirs hold this water at a working level. Below that the chart shows a flat line rather than a forecast.

The risk this page is built for is high water, not low. For a day on this stretch, the thing to check is the notices — lock works and closures — rather than a level.

https://www.hochwasser.rlp.de/flussgebiet/mosel/cochem

Day10

Reims; Paris

Monday 21 September

Not sailing

The ship does not sail on this day. Your itinerary spends it on land, so no river level applies to it.

The ship does not sail on this day.

Full details

Your itinerary spends this day on land. The ship is not sailing, so there is no stretch of river under it and no water level that applies to it.

What the ship does	it does not sail on this day
Level reading	none applies — no river is being sailed
Sensitive to low water	not at all, on this day

Waterlogged reads river levels, and this day has none to read. What happens on it is a question for your cruise line's own schedule, not for the water.

Day11–12

Paris

Tue 22 – Wed 23 September · France

Not sailing

The ship does not sail on this day. Your itinerary spends it on land, so no river level applies to it.

The ship does not sail on this day.

Full details

Your itinerary spends this day on land. The ship is not sailing, so there is no stretch of river under it and no water level that applies to it.

What the ship does	it does not sail on this day
Level reading	none applies — no river is being sailed
Sensitive to low water	not at all, on this day

Waterlogged reads river levels, and this day has none to read. What happens on it is a question for your cruise line's own schedule, not for the water.

Rain on your route — calculated daily

Rain forecast by Open-Meteo (commercial licence) · fetched 7 September 2026 at 05:16 UTC · covering 14 days, 7 September to 20 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.

The days of your own sailing are shaded: 12 September to 20 September. The forecast stops before your cruise does, so the rest of it is not here yet.

Rain forecast by Open-Meteo (commercial licence) · fetched 7 September 2026 at 05:16 UTC · covering 14 days, 7 September to 20 September.

Kaub Rhine · Germany

Far below the line

date, sky and daily high °C

Mo 7 Sep 31° Tu 8 30° We 9 20° Th 10 20° Fr 11 22° Sa 12 24° Su 13 26° Mo 14 24° Tu 15 26° We 16 18° Th 17 16° Fr 18 21° Sa 19 17° Su 20 21°

7 September20 September

14 days · mm/day upstream of this gauge

≈ 16 mm expected upstream over 14 days

Rain forecast by Open-Meteo (commercial licence) · fetched 7 September 2026 at 05:16 UTC · covering 14 days, 7 September to 20 September.

In past years, rain this light held the water level steady for a week or two. 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.

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 at different times.
The gauge gets a pulseA can briefly raise the level at the gauge.
Baseflow settles it 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 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
Gauge	Winter-runoff block	Summer-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.

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.
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.
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.

How to read every number on this page

"Water level now" is the authority's measured reading at the gauge named on this page. It uses centimetres from that . It is a level, not a depth of water under your ship. It is not the depth of the either, and it is not your ship's .
"Water level the ship needs" — written WLSN at each end of its bold dashed line on the graphs — is Waterlogged's own arithmetic on published reference figures for that stretch and the draft we hold for this ship. It is our line, plainly labelled, and it is not the operator's decision to sail.
The seasonal graph shows two different things. Left of the today line, solid blue shows the levels that were measured. Right of it, the dashed line shows the historical average for each date. It comes from what these gauges recorded on that date in past years. It is not a forecast of this autumn, and we do not draw one. We show it because that average keeps falling through October. That is useful to know before you sail.
Where a line comes from the record — Budapest — the page says so. There is still no maintained-depth model published for the Hungarian Danube, so instead of guessing at one we set our level from what actually happened: in 35 years of readings, every cruise-season day below it fell within a disruption somebody documented at the time.
Where no mark exists — Kienstock — we show the reading and the official marks and stop there.
Where the numbers come from. Measured levels for Kaub, Cologne, Pfelling and Hofkirchen are verified daily averages from . They cover 2015–2026 and are topped up from the live archive. Budapest and Kienstock readings come through and . For those two the solid line on the graph is drawn from our own recording of that live feed, which began in July 2026, so it is short and grows by a day each day; the graph says where it starts. The longer measured archive behind Kienstock is not ours to republish, so we do not draw it and we print no record sentence for it. For Budapest that changed on 17 August 2026: the General Directorate of Water Management gave us written permission to publish its own archive, and the average for each date now stands on 35 years of it. Each "normal for this date" uses a 31-day circular — the middle value, so half of past years were higher and half lower. The averages use 12 years of records on the German gauges, 35 years on Budapest and 25 years on Kienstock, from the projection engine's own doy_median_cm arrays. Record lines use an eleven-day window centred on the port's own date, across each gauge's whole archive. Budapest's levels come from Országos Vízügyi Főigazgatóság (OVF) / General Directorate of Water Management; where we work them into an average, those input data originate from the General Directorate of Water Management.
Nothing here is a forecast. The trend and the graph describe measured moves that have already happened. We do not model your cruise and we do not give you a percentage chance of anything.

The numbers on this page stay free.

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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.

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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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Viking Herja · Paris to the Swiss Alps

The Daily River Watch

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

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

The official forward outlook

Your daily sailing schedule

Zürich

Basel

The official forecast for this gauge

BfG's 6-week outlook for Maxau

Official forecast: Baden-Württemberg's own forecast for Maxau

Strasbourg

The official forecast for this gauge

BfG's 6-week outlook for Maxau

Official forecast: Baden-Württemberg's own forecast for Maxau

Speyer

The official forecast for this gauge

BfG's 6-week outlook for Maxau

Official forecast: Baden-Württemberg's own forecast for Maxau

Mainz

The official forecast for this gauge

BfG's 6-week outlook for Maxau

Official forecast: Baden-Württemberg's own forecast for Maxau

Koblenz

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub

BfG's 6-week outlook for Kaub

Official forecast: BfG 14-day forecast for Kaub, via ELWIS

Cochem

The official forecast for this gauge

BfG's 14-day water-level forecast for Kaub

BfG's 6-week outlook for Kaub

Official forecast: BfG 14-day forecast for Kaub, via ELWIS

Bernkastel; Trier

Official forecast: Rhineland-Palatinate flood forecast centre — Cochem

Reims; Paris

Paris

The detailed weather forecast for your route

Kaub Rhine · Germany

How rain becomes a water level

Why winter rain often does more

What "half-life" means here

Rules of thumb

How to read every number on this page

The Daily River Log Watch — free for this sailing

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