May 5th, 2014

Tonight's winds...the cold front still starkly
visible. This cold front will be pushed
northward starting tomorrow, and the
favorable southerly winds beneath will
expand into the rest of the state.

Hey folks!

I hope you all had a good day birding. With birds like Harris's Sparrow, American Avocet,  Upland Sandpiper, and Black-throated Gray Warbler among today's many reports, it seems like many of you did enjoy birding the migration today. Movements last night actually became heavier after I published the report, and arrivals and influxes throughout the state were evidence of this. The onset of heavy spring arrivals and influxes remain rather protracted, as species counts are only creeping up (except in Southern Illinois). The birds, just like the leaves, are taking their time.

So how about tonight? As predicted, wind maps relay that winds have become much more northerly everywhere in the state except for far southern Illinois. As expected, most of the birds don't want to mess with these chilly northeasterly headwinds, and are staying put for a good night's sleep. In Southern Illinois, tailwinds are still strong and direct, and birds there are hopping on for the ride. Looking forward, we can now actually see what will bring favorable conditions back on the surface analysis forecast. We'll get to that later. Let's take a look at what's over our heads by region:

Northern Illinois:

Tonight's radar...light in N and Central
IL...heavy in Southern Illinois.

Tonight, Northern Illinois is host to some rather adamant migrants that insist on battling the headwinds for a position further north. Looking at the radar, birds are moving northwest-ward in moderate concentrations in Northeast IL, and in light concentrations in Northwest IL (NW IL appears to be out, but here's the link, and here's NE IL). Lake Michigan may have something to do with this discrepancy, but your guess is as good as mine here. Anyway, I wouldn't expect any huge arrivals or influxes tomorrow morning, though there will definitely be some mixing of migrants in your area. But for the most part, birds are refueling right now, a fascinating time to observe migrant behavior. Looking forward, around 2 PM tomorrow afternoon, a low pressure system moving in from the west will move into Kansas. Its counterclockwise winds will be in perfect position to push the cold front sitting over South-central Illinois northward, at which point the front will become a northward-moving warm front. This front will move rather quickly through the Prairie State, and by 8 AM Wednesday, it will have brought favorable southerly winds to almost all of Illinois (wind forecast here). So Wednesday morning, and even more so Thursday morning, should be very good birding indeed. Good stuff.

THIS is the big news, that warm front...it's the above
mentioned front moving northward. Beneath it will be
favorable, southerly winds.

Central Illinois:
Central Illinois is also host to some courageous migrants fighting the headwinds, with moderate migration occurring throughout. Like in Northern Illinois, this concentration of movement likely won't last through the night, and tomorrow morning will probably only result in a light mixup of the birds in your local patch. Tomorrow is a refueling time at least for neotropical migrants, and there is hardly a better time to observe migrant behavior, especially that of their social interactions, than during refueling periods. So get out there and share what you observe! The wind forecast in Central IL is the same as Northern Illinois; the only difference is that favorable conditions come sooner! By tomorrow afternoon, a counterclockwise-rotating low pressure system in Kansas will push northward the boundary between the favorable winds in Southern Illinois and the cold, northerly winds of the rest of the state. Thanks to this system, winds should be favorably southerly by tomorrow night, so get your binocs ready for Thursday!

Heavy Migration over Southern IL

Southern Illinois:
Looking at national, composite radar, Southern Illinois--along with southern Indiana--stands out from the surrounding area with the heaviness of its migration. Birds are moving in heavy concentrations over S. IL tonight, as favorable southerly winds have remained there through the less favorable easterly and northeasterly winds seen in the rest of the state. So tomorrow should be great for observing arrivals and influxes (radar for SW IL, S-central IL, and SE IL)! Southern Illinois will be the refuge for migrants waiting to move northward once the right conditions present themselves...I can only imagine how the radar will ignite throughout the state in bright greens and blues when the time comes. Anyway, the wind forecast is equally good to Southern Illinois. Southerly winds are forecast to continue at least through the end of the forecast period on Wednesday evening, but looking at the movement of low pressure systems in the area, they will probably last longer. So sit back and enjoy the show!

Click me to predict the future

Cool! To predict for yourself what birds you'll be seeing tomorrow, here's my secret weapon from eBird.

And that's all I've got folks! Have a great night and happy birding!