Dane, Wisconsin · Live USGS instrumentation
Lake Mendota ice & water conditions
Open-water season. The freeze model activates when the 2026-27 hardwater season begins in November.
Updated · Species: yellow perch, walleye, northern pike, panfish
Air temperature · KMSN
77.0 F
Smoke · Jul 19, 12:00 PM CDT
Lake elevation · On-lake gage
849.67 ft
Lake Mendota at Madison · Jul 19, 11:30 AM CDT
Gage height · On-lake gage
9.71 ft
Lake Mendota at Madison · Jul 19, 11:30 AM CDT
30-day trend
Lake elevation · On-lake gage
849.71 ft
Lake Mendota at Madison · Jul 19, 11:30 AM CDT
Sun
Rise 5:36 AM · Set 8:33 PM
NOAA solar calculation · 43.11, -89.42
Know this lake's data
Daily stage records reach back to 1916. Mendota also carries one of the world's longest human ice-cover records (kept by the UW Center for Limnology since 1852).
Ice thickness reference (new, clear ice)
State DNR minimum guidance. It takes at least four days of below-freezing temperatures to form ice that supports a person, and white, layered, or refrozen ice is roughly half as strong: the DNR advises doubling these numbers for it.
| Activity | DNR minimum |
|---|---|
| Stay offNew clear ice below 4 inches does not support a person | Under 4 in |
| On foot (walking, ice fishing)New, clear ice minimum per Minnesota DNR | 4 in or more |
| Snowmobile or small ATV | 5 to 7 in |
| Side-by-side or full-size ATV | 7 to 8 in |
| Small car or SUVDriving on ice is never recommended | 9 to 10 in |
| Medium SUV or small truck | 11 to 12 in |
| Medium truck | 13 in or more |
Read this before you go out · draft, pending review (G3)
No ice is ever one hundred percent safe. This page is an educational reference built from public data and state DNR guidance. It is not a measurement of the ice on this lake, and it is not a statement that any ice will hold you.
Ice thickness varies across a single lake and can change overnight. Springs, current, snow load, slush, and refrozen cracks all produce weak ice that no model or nearby sensor can see.
Check the ice yourself, continuously: drill or spud test holes as you go, starting at shore. Carry ice picks, a throw rope, and a flotation aid. Never go out alone, and never drive out early or late season. When in doubt, stay off.
Sportsman Authority provides this reference as-is, without warranty. Decisions on the ice are yours alone.
Data sources
- USGS USGS-05428000 (Lake Mendota at Madison)US Geological Survey
- NWS station KMSN observationsNational Weather Service
- Daily temperatures for the freeze model: KMSN via NOAA Regional Climate CentersNOAA Regional Climate Centers
- Minnesota DNR: Ice safety guidelinesState agency
- Wisconsin DNR: Ice safetyState agency
- UW-Madison Center for Limnology ice recordsState agency
Data retrieved . Readings refresh throughout the day; USGS values may be provisional and subject to revision.
How the model works
Full method, coverage tiers, and every formula on the Ice & Water Report methodology page. Ice guides and gear research live in the ice fishing hub.