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Observations by Gary Fewless for Green Bay WI (Lat.N 44.51° Long. W 88.02° ), except as noted. For flowers lacking conspicuous petals or sepals I define "anthesis" as release of pollen by mature anthers.

April 2011 Mouse-over the photo for the identity of the subject
transition to spring

Apr 30

Carex pensylvanica (Pennsylvania sedge) in flower (anthesis). Plants in this same population first flowered April 10 last year, so we seem to be running almost 3 weeks later than last year. That can change quickly in the near future if the weather changes.

In summary, April was 2.1° F cooler than average and Green Bay received 6.25 inches of precipitation (snow included as water equivalent), 3.69 inches more than the average for April. We had 10.9 inches of snow which helped make this winter the 3rd snowiest in history (see April 20), and it was the second most precipitation ever for the month of April (only 0.2 inches below the record).

Apr 29

Salix humilis (prairie willow) in flower, Oconto County.

Anemone americana (=Hepatica americana, round-lobed hepatica), Sanguniaria canadensis (bloodroot) just a few flowers open in Forest County.

13-lined ground squirrel out in Oconto County.

Loons on Anderson Lake, Oconto County.

Apr 26

Steady rain today, total of 1.75 inches. The snow is gone everywhere in Green Bay except in the big piles where it is plowed in parking lots.

Apr 25 Cerastium fontanum (mouse-ear chickweed) in flower.
Apr 24

First day of fully open flowers for Forsythia sp. (Forsythia, horticultural), at my usual site in City of Green Bay. This same plant flowered first on April 5 last year. Reference photos 1 and 2 (not from this year).

First day of flower (anthesis) for Taxus custpidata (Japanese yew, horticultural), City of Green Bay. Also first day for flowering (anthesis) for Juniperus chinensis (Chinese juniper). If you notice a sharp increase in allergy symptoms now it is probably due to this species, which is commonly planted in yards.

A toad calling, Oconto County, Town of Pensaukee (Tom Erdman). This is very early.

First flowers of Erythronium albidum (trout lily), just a little north of UW-Green Bay in small patch of woods left within recent housing construction (Amy Wolf).

Apr 23

First day of flower for Capsella bursa-pastoris (shepherds purse) and also first day of dispersing spores for Equisetum arvense (field horsetail), UW-Green Bay.

The very earliest Caltha palustris (marsh marigolds) were in flower in springs on March 16 (see that date). By today more moderate populations are also in flower.

WIDNR reports that low numbers of Lake Sturgeon are now beginning to spawn on the Wolf River. Water temperatures are a bit cold, but necessity my trump tradition in this case.

Blue-gray Gnatcatcher at Pensaukee, Oconto County (Tom Erdman).

Apr 22

Snow depth is essentially zero this morning, but there are still many patches of snow left where it was deeper. Virtually all of the snow will be gone by tonight, since rain and a high of 43° F is predicted.

After all that has happened to delay development of the plants, I expect a very rapid development now as the weather warms.

Apr 21 Even though the temperatures weren't very warm, the snow depth was reduced to 3 inches in Green Bay by this morning.
Apr 20

Yesterday's storm dropped 9.9 inches of snow before midnight and light snow continues this morning adding another 0.2 inches. The total for the storm is therefore 10.1 inches, and the total snowfall so far this winter is 92.6 inches, making it the snowiest winter in 120 years and number 3 in the all time list (1889/90 had 103.6 inches and 1887/88 had 147.7 inches). Our average annual snowfall for the full winter is 55.2 inches. Three of the top 5 snowiest winters happened in the last 4 winters. There were numerous power outages as the wet, heavy snow bent and broke trees and wires. Canada Geese swimming on the East River last night had a thick layer of snow on their backs.


Apr 19 Another big snowstorm moves into Wisconsin. It's just started, but here are a few photos. We've already received enough snow to make this the 5th snowiest winter on record--and numbers 4 and 3 are in reach. I'll follow up later after the totals are known.
snow snow snow
Apr 18 Salix discolor (pussy willow) in flower (anthesis).
Apr 17

Acer rubrum (red maple) and Corylus americana (American hazel) in flower.

Some areas in Brown County had a little more snow in the morning.

Apr 16

A major storm system swept across the country April 14, 15 and 16, producing 243 tornados ranging from Oklahoma to Mississippi and Alabama and north through the Carolinas to Pennsylvania.

Moderate snow in Brown county (0.3 inches in Green Bay) in the afternoon. Melted by evening for the most part.

Apr 12

Yellow-headed Blackbirds returned to our area, Brown County, Sensiba Wildlife Area (Josh Martinez).

Also a report of Leopard frog calling at Sensiba Wildlife Area, in addition to Spring Peepers.

Apr 11 Yellow-rumped warbler seen on UW-Green Bay campus (Kari Hagenow).
Apr 10

Green Bay's daily high temperature was 76° F, our warmest temperature since October 8 (184 days).

Earthworms out on roads and sidwalks following last night's (but after midnight) rain. More rain in the evening as a powerful thunderstorm moved through the area, generating tornados not far to the south and west. A total of 0.75 inches of rain for this date. 11 tornados were reported in Wisconsin tonight, the largest outbreak of tornados in April.

Leopard frogs out, near the East River, Allouez, Brown County.

Yellow-bellied Sapsuckers, UW-Green Bay campus (Tom Erdman).

Apr 09

Prairie Pond is ice free today for the first time since Nov 30 (129 days ice-covered).

Green Frogs out and about, Point au Sauble, Brown County, WI (Dave Lawrence).

Mourning Cloak butterfly flying, UW-Green Bay (Tom Erdman).

Apr 08

Alnus incana (speckled alder) in flower (anthesis), Brown county, at my usual phenology site..

Prairie Pond is about 80% ice-free today, UW-Green Bay.

Apr 07

I saw my first Belted Kingfisher of the year today, though I have a report of a single bird about a week ago in the City of Green Bay.

Most general snow-cover is gone with only a little snow in areas where it has been drifted, piled or shaded, although there are many such little patches around.

The ice is deteriorating rapidly on lower Green Bay. The low angle of the photo underestimates the size of the open water farther away.

There has been a big reduction in ice-cover of Green Bay, and Tom Erdman reports that the big floating ice sheets have moved over to the west shore, effectively covering any open water and therefore the waterfowl have been forced to move out.

Baird Creek still flooding, but now it is easy to see the higher line it reached just a couple of days ago. Most of the general snowcover is now gone and in the absence of substantial rain the creek should fall quickly hereafter.

Leopard Frog on road, Brown county (Josh Martinez).

Giant piles of ice, blown across Green Bay by strong winds, and waterfowl in open water nearby (mostly Common Golden-eye, with a few greater Scaup, Red-breasted and Common Mergansers) Oconto County, WI, Town of Pensaukee (Tom Erdman).

Apr 06

Baird Creek still flooding, but a little past the peak now.

Spring Peepers calling, Oconto County Town of Pensaukee (Tom Erdman), and Manitowoc County (Kari Hagenow).

Apr 05

First day for Water Striders on Mahon Creek, UW-Green Bay. Last year the first day was March 17.

First returning Bluebirds on UW-Green Bay campus (Tom Erdman).

BairdCreek at flood stage again. Yesterday and today are near peak for the late snow melt.

Green Bay weather station lists snow depth at zero for the first time since the March 22/23 snow storm, after 2 days of "trace" measurements.

Tree swallows, City GB (Kari Hagenow).

Apr 04 First returning Black-crowned Night-Heron, Oconto County, Town of Little Suamico (Tom Erdman).
Apr 03

There was rain early and then enough sleet to cover the ground in white this morning--if you didn't look closely you could easily mistake it for an inch or so of snow. The Green Bay weather station reported 0.58 inches of precipitation, as water equivalent, including 0.5 inches of snow (sleet?).

We had a Great Egret back in our pond near the East River in Allouez, Brown County, looking miserable in the sleet. The pond is still mostly frozen, but the shallow water area near shore is open. Several reports of one or a few Phoebes back in our area in the last couple of days.

Much of lower (southern) Green Bay is still ice-covered though there is open water at the mouth of the Fox River and along the shipping channel.

This is about the peak of the second snow melt, lots of running water, Oconto County, town of Little Suamico (Tom Erdman).

Apr 02

We saw 8-10 White Pelicans flying along the Fox River this morning--the first I've heard of in Brown County this spring. Others have reported Double-crested Cormorants back in Brown County today too. Also a report of a single Loon on the Fox River in Green Bay. The Fox River is open now and crowded with boats of fishermen, below the DePere dam.

In spite of the lack of flooded fields (mostly still frozen) where they usually congregate, there are large numbers of returning Canada Geese (thousands) and Tundra swans (hundreds) in the Shiocton/Black Creek area of Outagamie County. Here's a flock of many geese and fewer swans flying over and feeding in a field. There are also Sandhill Cranes in the mix, but we've been seeing those for a while.

Apr 01

First day of flower (anthesis) for Acer saccharinum (silver maple) in City of Green Bay. For the last 26 years, the average first date of flower for this same tree was March 25.

I heard and then saw a flock of Tundra swans over the UW-Green Bay campus this morning.

The high temperature today was 46° F. Last year on this date the high was 75°!

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Last updated on May 20, 2015