Begin with the kind of flood information you need
A National Weather Service flood watch means conditions favour flooding; a warning means flooding is imminent or occurring. Neither is a map of every road already under water. A flash flood warning has a different urgency and may apply where rain is not falling at that moment. Check the issuing office, affected area and valid time before treating a colour on a national map as a local instruction.
The National Water Prediction Service supplies river and stream observations and forecasts. A gauge shows conditions at its measurement location. It cannot by itself establish the depth of water on every nearby street. Forecast values describe a possible future condition, while observed values describe measured water level or flow; always read the units, timestamp and flood-category labels separately.
Why the layers may appear to disagree
The PocketWorld flood overview shows provider-labelled global event information, not every US gauge or local warning. An event marker may summarize a large area and may be updated on a different schedule than an NWS warning. A missing marker does not cancel a warning. A marker that remains visible after a warning expires is not necessarily a new flood: inspect the event and retrieval dates before comparing.
River flooding, flash flooding and coastal inundation have different causes and lead times. A quiet gauge cannot rule out fast local flooding away from that stream. Nor does a watch mean flooding has been measured. Keeping these distinctions visible prevents a map screenshot from becoming an accidental safety claim.
A practical US checking sequence
For an address or journey, first open the current NWS forecast and alerts for the locality and read the complete alert text. If the concern is a river, follow the linked gauge in the National Water Prediction Service and compare observation time with forecast time. Then use PocketWorld for broader event context, noting its source and freshness label. Record the place, authority and time zone if you share the result.
Weather products and event records may be revised. If a saved image disagrees with a current authority page, do not silently substitute one for the other. Link the current source and explain which observation or forecast the screenshot captured. For evacuations and road closures, use local emergency and transportation authorities; PocketWorld is an informational map, not an alert or route-safety service. Our methodology explains retained snapshots.
When comparing two river gauges, do not infer that the water level between them is uniform. Tributaries, terrain and the timing of rainfall matter. A gauge can be rising even after rain has stopped locally, so the trend and forecast window belong alongside any single reading.
Data sources
References are linked beside the explanations above. This evergreen guide does not report current incidents.