Grub Detention Reservoir

Valley County, MT

MAYBEConfidence · Low
Best bite window
The highlighted window has passed. This read is still based on the latest cached weather; use the 7-Day forecast below for the next window.
Main reason
dry conditions across the window
Main risk
a front passing through

MAYBE on Grub Detention Reservoir — light winds and rising pressure after a passing system for this window. Watch a front passing through. Weather-only read (no on-water history calibrating this yet).

Next forecast window
MAYBE

Fri · Jul 24, 4 AM → 8 AM (America/Denver)

Full read

The latest cached fishing-weather read for Grub Detention Reservoir in Valley County, MT is MAYBE. Its highlighted window has passed, so use the 7-day forecast below for the next available window. The main factor in its favor was dry conditions across the window, while the main watch-out was a front passing through. Its cached forecast evidence included wind near 3 mph out of the southeast, gusting to 8 mph; surface pressure near 929 hPa on a rising trend; 0.00 inches of rain; and air temperature near 70 °F with overcast dominant. Confidence in this cached read is low; it was generated July 23, 2026, 11:45 AM UTC, and reads refresh on a daily cadence. This is a weather-only read built from forecast weather; it does not yet use on-water reports, and confidence is capped until local water data or feedback exists.

UPDATED July 23, 2026, 11:45 AM UTCBUCKET 2026-07-23ENGINE 0.7.0

Conditions at a glance

Wind
3mph

SE · gust 8

Rain / Weather
0in

Overcast

Temp
70°F

21°C · hum 66%

Pressure
27.43inHg

Rising

7-Day Fishing Forecast

One read per day — the bite call, the window, the weather behind it

  1. Thu · Jul 23
    Window passed
    MAYBE
    A front passing through
    97° / 63°F
    3 mph · SEgust 17
    0.00 in
    ↓ -4.3 hPa
  2. Fri · Jul 24
    4 AM → 8 AM
    MAYBE
    A front passing through
    97° / 75°F
    6 mph · SWgust 34
    0.00 in
    ↓ -2.3 hPa
  3. Sat · Jul 25
    4 AM → 8 AM
    MAYBE
    A front passing through
    108° / 79°F
    4 mph · Wgust 23
    0.00 in
    ↓ -2.3 hPa
  4. Sun · Jul 26
    4 AM → 8 AM
    MAYBE
    A front passing through
    102° / 82°F
    7 mph · NWgust 25
    0.00 in
    ↑ +4.6 hPa
  5. Mon · Jul 27
    4 AM → 8 AM
    MAYBE
    A front passing through
    100° / 73°F
    6 mph · NEgust 22
    0.00 in
    ↓ -3.3 hPa
  6. Tue · Jul 28
    8 AM → 12 PM
    MAYBE
    A front passing through
    100° / 75°F
    7 mph · Ngust 26
    0.00 in
    ↓ +1.9 hPa
  7. Wed · Jul 29
    1 PM → 5 PM
    MAYBE
    A front passing through
    106° / 75°F
    7 mph · Egust 19
    0.00 in
    ↓ +1.3 hPa

Last 3 days

Recent context — what just happened

Pressure
Steady
+1.0 hPa over 72h
Rain
Dry stretch
0.00 in totallast 72h
Wind
Calm wind
8 mph · gust 24 · E
Temperature
Warmer
+5.0°F over 72h88–57°F range

Weather-only read. Confidence is capped until local water data or feedback exists.

Nearby waters

Weather data by Open-Meteo — CC BY 4.0. Fishing Weather derives the fishing read.