HatchWatch
Klekkeprognoser for fluefiske
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
When does the hatch start where you fish? HatchWatch estimates mayfly hatch dates for Norwegian waters and tells you when it is getting close.
HatchWatch estimates when mayflies hatch in Norwegian lakes and rivers, so you can plan your fishing around the insects instead of the calendar.
The model is built on heat sums from air temperature, water temperature, ice-out and snow, from MET Norway and NVE. It updates daily. Early in the season the uncertainty is biggest, and it shrinks as real measurements replace the long-range forecast. Think of it as a weather forecast for hatches.
WHAT YOU GET
• A map of Norway showing where the hatch is under way, where it starts soon, and where it is coming up
• A timeline you can drag to watch the hatch wave move north through the season
• An estimated hatch start for every water, with the uncertainty stated in days
• Season list: all waters sorted by how close the hatch is
• History for every water, so you can see how this season compares with earlier years
• Spinner fall outlook for the evening, from wind, temperature and cloud
• My waters: save your favourites
• Find the nearest water with one tap
NOTIFICATIONS
Pick a water and what you want to know about, and the app tells you:
• when the hatch start is getting close
• when the estimate moves two days or more
• when the evening looks good for a spinner fall
• when the season opens
HONEST ABOUT UNCERTAINTY
HatchWatch shows how well each water is calibrated. In some places the model has been tested against several years of observations and typically lands within a few days. In others the estimate is rougher, and it says so. A model is a tool, not an answer key. Local conditions and the weather on the day decide in the end.
CONTRIBUTE
The model gets better with real observations. Seen a hatch? Report it from the app and it is used to improve the estimates for everyone.
Free, no ads, no account. Made by a fly fisher, for fly fishers. Available in English and Norwegian.
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
HatchWatch now speaks English. The app follows your phone's language, and you can switch between English and Norwegian in the menu at any time.
The developer, Stian Midtdal, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Contact Info
- User Content
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Location
- Identifiers
- Usage Data
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Stian Midtdal
- Size
- 1.9 MB
- Category
- Sports
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
- iPhone
- Languages
- Norwegian Bokmål
- Age Rating
4+
- 4+
- Copyright
- © 2026 Stian Midtdal