Michigan Phenology

Saginaw Bay to the AuSableSummer

Friday, September 4, 2026.

AuSable
905 cfs
steady
Water
64 °F
river
Season
13d late
1947 GDD
Moon
42 %
last quarter
Daylight
13:03
-2.9 min/day
Hatching: Trico, White Fly Plant now: Radish and arugula Overhead: Lyra Color: first turning
The read

Saginaw Bay is 78 degrees, 0 mph out of the and 0.3-foot chop. Good water for getting the kayak out along the beach. The Kawkawlin reaches the bay a half mile down the shore, and the Saginaw River up the way is running 1910 cfs, rising. Degree days stand at 1947 against a normal of 2156, so the season is running about 13 days late. Against the long-term normal, accumulated heat is running ahead by 228 growing degree days. Daylight is 13 hours 3 minutes, shortening about 2.9 minutes a day, and the soil at six inches is 76 degrees, warm enough for morels and the warm-season garden. First frost here typically comes in early October, leaving about 31 days of growing season. The Trico is the hatch on the water now. Velvet shedding marks peak summer in the woods and the buck's transition toward rut; the bucks start moving more aggressively. On the bay, 1 notable bird is being reported, including Red-necked Phalarope. Bay County is in abnormally dry on the latest Drought Monitor.

Correlation: First hard frost and Walleye fall feed-up overlap on the calendar right now. Watch whether they track together as the years bank up.

JFMAMJJASOND
Tap any dot for the detail and projection.
Water and iceFishHatchesBirdsBloom and colorGarden, zone 6aWildlife
The season itself
By the heat it has gathered, the year is running about 12 days behind normal.
1947 growing degree days gathered so far against 2156 normal for the date. The hatches, blooms and garden dates below are shifted to match. Bird migration and lake levels are not, since they follow daylight and the basin rather than the heat.

The almanac

Where the year stands, read from the day's numbers and the calendar. Written each morning, kept as a record. Not a field report.

Goldenrod has opened along the Thumb roadsides and aster is coming on behind it, purple and white in the low wet edges, though both are arriving nearly two weeks late by the record. The soil still holds 73 degrees of summer, enough to keep the trico spinners working the AuSable riffles in the early morning, their white wings nearly invisible until the light catches them. Katydids have taken up their nighttime rasp in the woodlots. King salmon are pushing in from the lake, feeling what the shortening days insist upon even when the warmth lingers. Sugar maple and the first hard frost are perhaps three weeks out, perhaps less. Stand at the river's edge before sunrise and watch the spinner fall over any slow flat water.

2026-09-04

Happening now

Goldenrod first bloomnow
Gold along every roadside and field.
Fall warbler migrationnow
Quiet, plumage-puzzle season.
Katydid song beginsnow
The nighttime rasp of late summer.
Trico hatchnow
Tiny morning spinners.
Walleye summer lowsnow
Walleye retreat to deep water and cool zones.
Joe-Pye weed bloomnow
Tall dusky-rose heads in wet ground.
White-tail antlers in velvetnow
New racks growing under velvet.

Next three weeks

White-tail velvet shed5 d
Bucks rubbing off the velvet summer coat.
Salmon run, rivers9 d
Kings push up out of the lake.
Aster bloom9 d
Purple and white, the last nectar.
Sugar maple first color20 d
The first reds and oranges in the canopy.

Just past

Saginaw Bay summer calm2 d ago
Light winds, warm bay, ideal for boating and surface life.

Connections in play

The signals nature is giving right now, and what each one points to on the rivers, in the woods, and in the garden.

White-tail velvet shedactive now
Velvet shedding marks peak summer in the woods and the buck's transition toward rut; the bucks start moving more aggressively.
Goldenrod first bloomactive now
Goldenrod opening is the turn toward fall: monarchs and warblers begin fueling for the trip south.
Aster bloomactive now
Asters are the final fuel of the year for the southbound monarchs.
Katydid song beginsactive now
When the katydids start calling, the old rule puts first frost about ninety days out.
Sugar maple first colorin about 8 days
First maple color runs with the kings pushing into the rivers and the brook trout starting to color up for the spawn.
Fall color peak, NE Michiganin about 21 days
Peak color in the canopy. The brook trout are in full spawning dress, the salmon are on their runs, and the last warblers and woodcock push south.
First hard frostin about 21 days
First hard frost ends the warm-season garden and sweetens the kale, carrots, and brassicas.
no frost in the 7-day outlook
Walleye fall feed-upin about 13 days
Fall walleye feed heavily as water cools; this is the second-best season after spring spawn.
River:the trout water, a trip north
AuSable flowlive
905cfs
USGS gauge
River waterlive
64deg F
AuSable, USGS
Lake Huron levellive
176.73m IGLD
Saginaw Bay, NOAA
Saginaw Bay windlive
0mph
out of the , buoy 45203, 0.3 ft seas
Bay water, buoylive
78deg F
Saginaw Bay buoy 45203
Lake surface, satellitelive
74deg F
GLSEA whole-bay average, 2026-09-03

The turning year

the usual year

All seventy-one events, filed under the month each one peaks in. These are the ordinary dates, the year as it usually runs here. This year is running about 12 days behind normal, so the heat-driven ones are arriving off these dates by about that much. The months are uneven on purpose. May carries fifteen of them and January carries two, which is what the year is actually like here.

January

2

The lakes sit at their yearly low and the great horned owls are already on eggs. The first insistence that something has begun while everything looks finished.

  • Great horned owl nestingJan 25
  • Great Lakes seasonal lowJan 20

February

2

Bucks drop their antlers into the snow and the eagles settle onto nests. Nothing is green, but the year has committed itself.

  • White-tail antler castingFeb 4
  • Bald eagle nesting beginsFeb 19

March

7

Sap runs in the maples, red-wings come back to the cattails, and the woodcock begins his sky dance at dusk over wet ground. The first month you can hear the change.

  • Maple sap runMar 7
  • Red-winged blackbird returnMar 8
  • Skunk cabbage bloomMar 13
  • Tundra swans northMar 20
  • Sandhill crane returnMar 21
  • Red and silver maple floweringMar 25
  • American woodcock displayMar 29

April

11

Ice leaves the inland lakes, steelhead push up the tributaries, and the Hendricksons come off the AuSable. On the bay the northeast wind season opens.

  • Willow and pussy willow catkinsApr 6
  • Ice-out, inland lakesApr 10
  • Quaking aspen catkinsApr 14
  • Steelhead run, tributariesApr 15
  • Common loon returnApr 20
  • Forsythia bloomApr 24
  • Sucker spawnApr 25
  • American turkey spring gobbleApr 25
  • Hendrickson hatch, AuSableApr 28
  • Walleye spring spawnApr 30
  • Saginaw Bay NE wind seasonApr 30

May

15

The crowded month, and the one that rewards attention most. Lilac, morels, warblers, apple blossom, the median last frost, and oak leaves reaching the size of a squirrel's ear.

  • Dandelion bloomMay 5
  • Serviceberry bloomMay 5
  • Lilac first bloomMay 8
  • Morel seasonMay 10
  • Oak leaf-out, squirrel's earMay 12
  • Ruby-throated hummingbird arrivalMay 13
  • Baltimore oriole arrivalMay 13
  • Warbler migration peakMay 14
  • Oak flowering, catkinsMay 14
  • Last spring frost (median)May 15
  • Apple blossomMay 17
  • March Brown and Sulphur hatchesMay 18
  • Black cherry bloomMay 18
  • Flowering dogwood bloomMay 20
  • Warm-season transplanting, 6aMay 28

June

10

Fawns in the tall grass, fireflies over the ditches, and the Hex hatch on the AuSable, which is the one night of the year the big trout feed without caution.

  • Black locust bloomJun 2
  • Brown Drake hatchJun 5
  • Eastern white pine pollenJun 9
  • White-tail fawningJun 9
  • Breeding bird peak songJun 10
  • Monarch arrivalJun 10
  • Fireflies emergeJun 21
  • Hexagenia (Hex) hatchJun 22
  • Common milkweed bloomJun 27
  • White-tail antlers in velvetJun 29

July

4

The bay comes to its warmest and its calmest, the lakes to their seasonal peak. Basswood in bloom, and the year holding still for a few weeks.

  • American basswood bloomJul 7
  • Great Lakes seasonal peakJul 15
  • Joe-Pye weed bloomJul 29
  • Saginaw Bay summer calmJul 29

August

4

Trico spinners at first light, katydids after dark, and the first goldenrod along the roadsides. The turn begins well before anyone admits it.

  • Walleye summer lowsAug 3
  • Trico hatchAug 5
  • Katydid song beginsAug 13
  • Goldenrod first bloomAug 21

September

we are here5

Velvet comes off the antlers, the warblers go back south, and the sugar maples show their first color in the crowns.

  • White-tail velvet shedSep 7
  • Fall warbler migrationSep 10
  • Aster bloomSep 19
  • Salmon run, riversSep 20
  • Sugar maple first colorSep 23

October

6

Peak color through the northeast, the first hard frost on the garden, and trout moving onto the spawning gravel. The walleye feed up for winter.

  • Fall color peak, NE MichiganOct 8
  • First hard frostOct 10
  • Walleye fall feed-upOct 10
  • Woolly bear caterpillarsOct 13
  • Brook and brown trout spawnOct 19
  • Witch hazel bloomOct 27

November

3

The rut, the cranes staging, the swans going south. The last of the moving, and then the woods go quiet.

  • Sandhill crane fall stagingNov 1
  • Tundra swans and waterfowl southNov 5
  • White-tail rut peakNov 16

December

2

Ice takes the inland lakes, and in some years the snowy owls come down out of the north. The year closes as quietly as it opened.

  • Ice-in, inland lakesDec 20
  • Snowy owl irruption (some years)Dec 20

Hatch and emergence forecast

computed

This season's accumulated heat against known degree-day thresholds, with the aquatic hatches cross-checked against the live AuSable water temperature. Estimates, not promises; emergence shifts with the weather.

Tricoon now
tiny morning spinner falls
White Flyon now
late-summer evening blizzard