May 11th, 2014

Tonight's surface analysis

Hey all!

Migration has found its way into full swing, and we birders in Illinois have noticed. Tons of you were out birding today...my inbox chimed from my phone with more than 50 reports from around the state! Compare that to some days in February when I received four at most, and two of those were eBird alerts.

Tonight, in the wake of storm activity today and last night, the doors have finally opened for migration. After this last storm system passes out of western Illinois, Illinois skies will be open and full of southerly winds for the birds. Tonight has already been a night of explosive migration, so let's take a look by region:

Northern Illinois:

Tonight's winds

Northern Illinois, at least so far tonight, has received the short end of the stick. Migration is even on the light NE Illinois. The storm system that passed over N Illinois today is still dragging its tail out of a region south of the city, and this is blocking birds from moving up over Chicago and beyond. This is especially obvious in an area just north of the severe storm's final act in Illinois, where there is no migration whatsoever. NW Illinois is slightly harder to explain. Thanks to the contents of tonight's slightly convoluted surface analysis, winds are slightly southwesterly, so this may be facilitating less migration. Regardless, it's seems likely that migration well pick up as the night goes on, but there will be slightly less influx, and slightly fewer arrivals, in Northern Illinois than in the rest of the Prairie State. So that's that. As far as the wind forecast goes, winds are forecast to remain southerly until Tuesday morning, when winds will become westerly thanks to the arrival of a cold front. Until then, the only thing deterring birds will be storm activity (like what will pass through tomorrow), so live it up in the field when you can!
side of moderate right now. I can explain this at least in

The point on Tuesday when the cold
front from the west will bring W
winds.

Central Illinois:
As if to make up for the lack of migration in many areas last night, Central Illinois skies are currently host to explosive amounts of migration, pushing at extreme level concentrations. Tomorrow should be an outrageously good day to bird Central IL, so if you can, get out there! So how long will it continue, then? Winds are forecast to shift from their current southerly position to a more westerly one by Tuesday morning, and after that point, winds will be shifting up to northwesterly, so live it up tomorrow while you still can! Favorable winds won't be lasting much longer this week!

Southern Illinois:
Southern Illinois has a similar story tonight. Migration is extremely heavy like in Central Illinois (SW IL, S-central IL, SE IL), and tomorrow should be a fantastic day to bird Southern Illinois (although when isn't a good time to bird Southern Illinois?). The forecast is also the same for S Illinois, with winds forecast to become westerly and then northwesterly starting Tuesday morning. So if you can, get out there and enjoy the birds tomorrow!

So there's the forecast, ladies and gentlemen. The bottom two thirds of the state are witness to enormous migration tonight, while the top third is witness to slightly lighter movement, at least for now. We'll see how this lays out. Here's the eBird page to predict which birds you'll find tomorrow.

Thanks everyone! Have a great day tomorrow!

Nick Minor, on behalf of the Illinois Ornithological Society and the Illinois Young Birders' Club