u/Trailhead_Tom

Good news today: every tracked Minnesota region is Moderate. There are no High or Severe weather-pressure zones.

Sunshine, low rainfall and afternoon wind should give most outdoor growers favorable drying and harvest conditions through Sunday. Existing damage from earlier wet weather can still appear inside dense flowers, but the current pattern is helping—not hurting.

Region	Pressure	Outlook
Brainerd / Crow Wing	45 — Moderate	Only 0.06” of rain over the past week. Sunny, breezy and dry through Sunday.
Bemidji / Northwest	48 — Moderate	Sunshine and gusts near 25 mph provide strong drying. Rain may return Sunday night or Monday.
Duluth / Northeast	46 — Moderate	About 0.33” last week. Sun and gusty west winds should dry exposed flowers effectively.
St. Cloud / Central	44 — Moderate	About 0.21” last week. Dry, sunny conditions continue through the weekend.
Twin Cities	49 — Moderate	Only 0.03” last week. Warm, breezy weekend weather should support continued drying.
Marshall / Southwest	42 — Moderate	Nearly rain-free. A stray Friday storm is possible, but extended wetness looks unlikely.
Mankato / South-central	47 — Moderate	Warm, windy and predominantly dry through Sunday.
Rochester–Winona / Southeast	49 — Moderate	Roughly 0.13–0.14” last week. Several sunny drying days are ahead.

Frost: No widespread frost or freeze danger is expected through the weekend. Preliminary forecasts approach 32°F near Bemidji and the mid-30s around Brainerd and St. Cloud Tuesday morning, so northern growers should monitor updates—but a damaging freeze is not yet established.

Best opportunity: Saturday currently looks like the strongest statewide drying and harvest day. Warm temperatures and wind should help remove surface moisture, although unsupported branches may need protection from stronger gusts.

Next concern: Showers could return Monday into midweek. NOAA also favors wetter-than-normal conditions around Oct. 12–16, but this does not currently resemble another prolonged saturation event.

MNtrees Outdoor Harvest Signal

No new firsthand bud-rot or crop-loss report was found in the past 24 hours, and discussion has eased since Monday.

Recent reports remain localized:

• Oct. 5 Bud Rot Watch — Eden Prairie and Minneapolis growers reported isolated rot, while nearby plants or remaining colas stayed clean. Firsthand claims without new photos.
• My 2026 grow season — Crow Wing County grower documented cultivar-dependent rot and harvesting one to two weeks early. Firsthand report with photos.
• Sept. 30 Bud Rot Watch — Updates from Hibbing, Golden Valley and South Minneapolis ranged from affected buds to a healthy plant with good airflow. Mixed firsthand reports.

This week’s grower checklist:

• Inspect inside dense colas, especially around browned or dead sugar leaves.
• Keep questionable material separated from clean flower.
• Sanitize tools between affected and healthy plants.
• Use the sunny, windy window if plants are mature and ready.
• Watch Monday’s rain timing and Tuesday’s northern temperatures.

If you’re growing outdoors, share your county or nearest city, whether you’re holding or harvesting, and whether you’re seeing no rot, isolated spots or spreading damage. Photos and honest field reports help everyone build a clearer Minnesota picture.

Weather pressure is not a disease diagnosis or crop-loss estimate. Compiled from representative station data and forecasts by Trailhead Cannabis Company in Brainerd.

Sources: National Weather Service · NOAA Climate Prediction Center · Iowa Environmental Mesonet Minnesota ASOS archive · University of Minnesota Extension gray-mold guidance

Tuesday’s rain was lighter than feared in several regions. However, Minnesota woke up to widespread fog, dew points in the upper 50s to mid-60s and 94–100% humidity.

The next meaningful drying window is later today through Friday. Saturday may briefly rewet plants.

These scores measure weather pressure—not the probability that your plants have rot and not a statewide crop-loss estimate.

Region	Score	What to watch
Brainerd/Crow Wing	76 — High	0.90″ over three rain days during the past week. Fog, 96% RH and a 61°F dew point this morning; sun develops today with better wind Thursday. Saturday showers may interrupt the dry-down. Falling.
Northwest/Bemidji	72 — High	Fog and 100% RH this morning, followed by sun today through Friday. Saturday brings a 50% shower chance. Falling, then possible weekend rewetting.
Northeast/Duluth	68 — High	0.24″ over two measurable rain days, plus traces. Morning fog/94% RH gives way to sun; Thursday wind and Friday sun provide strong drying. Showers likely Saturday. Falling.
Central/St. Cloud	82 — Severe	1.14″ over three rain days, including 0.38″ Tuesday. Dense fog, 96% RH and a 63°F dew point this morning. Thursday–Friday improve; Saturday has a 40% shower chance. Falling slowly.
Twin Cities	87 — Severe	1.19″ over four rain days, including 0.92″ Tuesday at MSP. Fog, 96% RH and limited wind this morning; Thursday stays cloudy before Friday sun. Active, then falling.
Southwest/Marshall	88 — Severe	1.13″ over four consecutive rain days. Fog, 100% RH and calm conditions this morning. Sun develops today, with a better Thursday–Friday dry-down. Beginning to fall.
South-central/Mankato	90 — Severe	At least 1.68″ over four confirmed rain days; incomplete station data means the actual weekly total may be higher. Fog, 100% RH and clouds today–Thursday keep dense flowers vulnerable. Still active.
Southeast/Rochester–Winona	85 — Severe	Rochester recorded only a trace Tuesday, but fog, 100% RH, a 65°F dew point and clouds through Thursday maintain strong leaf-wetness pressure. Another shower is possible tonight. Falling Friday.

Frost and drying outlook

No broad freeze danger is forecast through October 6. Bemidji and Brainerd may fall to roughly 37–39°F on the coldest nights, so isolated low-lying northern spots could see patchy frost. Statewide, moisture remains the larger concern.

Wednesday afternoon through Friday is the main drying opportunity. Saturday showers could cause one more wetting cycle, especially from Brainerd and Bemidji through Duluth and St. Cloud. Sunday–Monday currently look sunny and breezy.

The longer-range signal is favorable: NOAA leans warmer and drier than normal for Minnesota October 5–13, lowering the likelihood of continuous two-week weather pressure.

MNtrees Outdoor Harvest Signal

No material new firsthand crop-loss report was found during the past 24 hours. Recent reports remain localized and mixed:

• Brooklyn Center: An uncovered grower found confirmed internal rot in one cola after a dead leaf pulled out easily, removed the affected section and harvested about 30% of that plant. They estimated approximately 5% of the crop affected. Firsthand claim without a rot photo.
• Rochester: A covered outdoor grower using a constant fan reported no brown sugar leaves or affected buds despite heavy humidity. Firsthand clean report without photos.
• Brooklyn Center: A second grower harvested one mature plant and reported minor powdery mildew beginning on another. Firsthand claim without photos.

Read the Sept. 28 community thread

Reddit reports are anecdotal. Individual comments do not establish regional crop loss, but they help identify where problems are—or are not—appearing.

Today’s field check

Once the fog burns off:

• Open several dense colas rather than inspecting only the surface.
• Check around dead or easily detached sugar leaves.
• Look for brown or gray interior tissue and musty odor.
• Remove questionable material without shaking it over clean flowers.
• Use today’s sun and Thursday’s wind to improve airflow before Saturday.

Please comment with:

• Nearest city or region
• Cultivar
• Uncovered, covered or greenhouse
• Clean, suspected rot or confirmed rot
• Approximate percentage affected
• Holding, harvesting early or already chopped
• Photo included: yes or no

“No rot” reports are just as useful as damage reports.

Weather sources: National Weather Service · Iowa Environmental Mesonet · NOAA Climate Prediction Center

Posted by Trailhead Cannabis in Brainerd to build a clearer Minnesota outdoor-harvest picture from actual grower observations.

Quick follow-up to Tuesday’s statewide outdoor thread. Thanks to everyone reporting what they’re actually seeing.

Community signal so far:

• Central Minnesota: one grower estimates roughly 10–15% rot in an outdoor garden and under 10% in a greenhouse.
• Rochester: a grower removed several rotting buds.
• Southeast Minnesota: one grower found two small rot spots while harvesting.
• Brooklyn Center, the northwest Twin Cities suburbs and north of Rochester: growers reported no visible rot so far.
• Wind exposure and overhead cover appear to be helping some plants, but individual reports cannot establish regional loss.

These are anecdotal firsthand reports—not a statewide crop-loss estimate. Read the earlier reports here:
https://www.reddit.com/r/MNtrees/comments/1wnaqp7/minnesota_outdoor_growers_bud_rot_watch_sept_22/

Sept. 24 weather-pressure watch:

🔴 Highest concern

• Southwest/Marshall: Rain, fog and clouds return Thursday, followed by additional rain chances Friday and Saturday.
• South-central/Mankato: Thursday showers and drizzle may be followed by another wet period Saturday.
• Southeast/Rochester–Winona: Recent saturation plus confirmed isolated rot reports keep this region elevated. Saturday brings another likely rain period.

🟠 High watch

• Brainerd/Crow Wing: Approximately ¼–½ inch Thursday, limited Friday drying and more likely rain Saturday.
• Northwest/Bemidji: Roughly 0.35–0.75 inch possible through Thursday, with another rain period Saturday.
• Northeast/Duluth: Less rainfall, but persistent clouds, cool nights and additional Thursday/Saturday shower chances.
• Central/St. Cloud: Approximately ¼–½ inch Thursday with fog or drizzle, then more rain Saturday.
• Twin Cities: Thursday showers and drizzle, limited Friday sun and likely Saturday rain.

The main concern is not one storm by itself. It is repeated wetting, humid nights and insufficient sun between rain periods. NOAA also favors wetter-than-normal conditions around the Upper Mississippi Valley as September ends.

Please keep the field reports coming. Copy this format:

• County or nearest city:
• Outdoor, covered or greenhouse:
• Visible rot: none / isolated spots / spreading
• Approximate loss, if any:
• Harvested, harvesting early or still finishing:
• Photo included: yes / no
• Anything helping—wind, cover, cultivar or plant spacing:

Please don’t handle visibly affected flowers more than necessary, and don’t treat mold-affected material as usable simply because it could be processed.

We’re tracking weather pressure—not diagnosing anyone’s plants. “No rot” reports are just as useful as loss reports because they help show where crops are holding up.

Today and Wednesday look like Minnesota’s best drying window since last week’s rain—but another wet cycle may begin Wednesday night or Thursday.

Current weather-pressure ratings:

• Brainerd/Crow Wing: Moderate
• Bemidji/Northwest: Moderate
• Duluth/Northeast: Moderate
• St. Cloud/Central: High
• Twin Cities: High
• Marshall/Southwest: Severe
• Mankato/South-central: Severe
• Rochester–Winona/Southeast: Severe

Southern Minnesota remains the biggest concern. Rochester recorded roughly 2.7 inches over the past week, while Marshall received another 0.36 inch Monday. Several southern areas have experienced five or six days of rain, fog, heavy dew or limited drying.

This does not mean those regions have confirmed crop loss. These are weather-pressure ratings based on rainfall, humidity, temperatures and drying opportunities—not observed Botrytis or a prediction that a certain percentage of plants will be lost.

Let’s build a better picture from the ground. If you’re growing outdoors, comment with:

1. Your zone or nearest city
2. Whether your plants are uncovered, covered or in a greenhouse
3. Any visible rot, brown interior tissue or dead sugar leaves
4. Whether you’re holding, harvesting early or already chopping
5. Photos, if you’re comfortable sharing them

Please report what you’re actually seeing—not what you assume is happening elsewhere. We’ll summarize the regional reports without identifying anyone’s exact location.

We’re posting from Trailhead Cannabis in Brainerd and trying to turn this into a useful Minnesota outdoor-harvest watch for the community.