WASHINGTON — Labor Day has come and gone, the days are getting shorter, school has started, and football season is underway.

And now with 153 days until the Feb. 3 Iowa caucuses, here are the five storylines we’re watching this month — and the rest of this fall.

Does the U.S. economy continue to feel shaky? On Friday, U.S. consumer confidence fell the most since 2012, according to the University of Michigan’s survey. But that contrasted with another survey from the Conference Board, which showed only a slight dip in consumer confidence. What will the economic data for September bring us? How much smaller does the Democratic field get? The size of the Democratic presidential field is already getting smaller — due to the heightened requirements to make this month’s debate in Houston. But how much smaller will it get? By the way, the candidates not named Biden/Sanders/Warren will have to figure out what to do next, especially if Biden continues to maintain his altitude in the race. Do House Democrats pursue impeachment? We’re now up to 134 House Democrats who support beginning impeachment proceedings against President Trump — so more than half of their majority. But it’s nearing now-or-never-time for Speaker Pelosi and the Dems with the 2020 contests approaching. How many more GOP retirements will we see? Late last week, per NBC’s Alex Moe, Rep. John Shimkus, R-Ill., announced he won’t seek re-election in 2020, becoming the 12th House Republican to make that decision. And as Rep. Billy Long, R-Mo., tweeted in July, more retirements often happen AFTER the August break. How serious of a primary challenge will Trump get? Former South Carolina Gov. Mark Sanford has postponed announcing his decision on whether to mount a primary challenge against President Trump — due to Hurricane Dorian. But if he gets in, that will mean the president has three GOP challengers: Sanford, Joe Walsh and Bill Weld. And remember, no modern incumbent president who has received a credible or semi-credible primary challenge has gone on to win re-election.

Trump’s lost summer

Meanwhile, the Washington Post sums up President Trump’s summer, which was marked more by controversies than accomplishments.

“When President Trump presided over the battle tanks and fighter jets, the fireworks and adoring fans on July 4, he couldn’t have known that the militaristic ‘Salute to America’ — as well as to himself — would end up as the apparent pinnacle of the season,” the paper writes.

“What followed was what some Trump advisers and allies characterize as a lost summer defined by self-inflicted controversies and squandered opportunities. Trump leveled racist attacks against four congresswomen of color dubbed ‘the Squad.’ He derided the majority-black city of Baltimore as ‘rat and rodent infested.’ His anti-immigrant rhetoric was echoed in a missive that authorities believe a mass shooting suspect posted. His visits to Dayton, Ohio, and El Paso after the gun massacres in those cities served to divide rather than heal.”

Manchin’s decision to make

NBC’s Frank Thorp reports that Sen. Joe Manchin, D-W.V., will announce this morning whether he’ll run for governor in 2020 (he was the state’s governor from 2005 to 2010), or if he’ll remain in the Senate.

If he runs for governor and wins, Manchin could appoint a temporary successor who could stay in the Senate before a special election in 2022.

But that is also two years short of Manchin’s full term, which runs through 2024.

So, theoretically, Manchin running for governor could cost the Democrats two years of his Senate term.

2020 Vision: Biden’s up with new digital ads on health care

NBC’s Marianna Sotomayor reports that Joe Biden’s campaign is releasing a series of new digital ads that focus on health care and recount his family’s personal tragedies.

On the campaign trail today

Bernie Sanders stumps in New Hampshire… John Delaney also is in the Granite State… Tulsi Gabbard and Michael Bennet spend their day in Iowa… Elizabeth Warren — along with Rep. James Clyburn — holds a town hall on student debt in South Carolina… And Tom Steyer holds a town hall in Oakland, Calif., on climate change.

Dispatches from NBC’s embeds

Kamala Harris agreed with Beto O’Rourke’s plan to buy back assault rifles when NBC’s Deepa Shivaram asked her about it. “Yeah, I think it's a great idea. But listen, I don't think we lack for great ideas. As I've said many times, we've been having great ideas for decades. The problem is that Congress has not had the courage to act. And that is why, from the beginning, I have said my agenda includes attempting to get Congress to act. But if they don't within the first 100 days of my administration, I'm going to take executive action. Because what we need is action. We have a failure of supposed leaders to act. So, I applaud all the good ideas, they are great, but we need action.”

Joe Biden was also asked about the gun debate while campaigning on Labor Day. And while the former vice president tends to push for compromise between the two parties, per NBC’s Marianna Sotomayor, that’s not the case for Biden on guns. “I think there’s no compromise,” he said when asked if he would try and break a deal between both parties. “This is one we have to just push and push and push and push and push’ to pass landmark gun reform.”

Data Download: And the number of the day is …seven

Seven.

That’s the number of hours that New York City Mayor Bill de Blasio spent at City Hall in May – the month when he launched his presidential bid – per records reviewed by the New York Post.

De Blasio “showed up at his office on just six occasions in May, taking part in two meetings, four events and five phone calls, one of which was his weekly appearance on WNYC radio,” the Post says.

“The 11 appointments amounted to a meager one-fifth of the 50 meetings, calls and other events at City Hall on de Blasio’s calendar for May 2018. He had a total 152 city events scheduled for the month.”

Tweet of the day

The Lid: I’ve got you, babe

Be sure to check out the pod from Friday, when we observed how the past summer seemed like “Groundhog Day,” where nothing really changes.

ICYMI: News clips you shouldn’t miss

Former GOP Lt. Gov Michelle Fischbach will challenge Democratic Rep. Collin Peterson in Minnesota.

Jonathan Allen writes that Trump’s 2020 pitch includes plenty of laments about what he’s unable to get done.

We’re a week out from the special election in North Carolina’s 9th district.

Pete Buttigieg is starting to build a big field network in Iowa and New Hampshire.

Here’s what we know so far about the motivations of the gunman in West Texas who killed seven people over the weekend.

Trump Agenda: Worries about North Korea

Experts are worried about North Korea’s missile tests — even if the president is downplaying them.

Mike Pence is defending the decision to stay at a Trump property in Ireland that’s far away from his meetings in Dublin.

Congressional Democrats are planning an inquiry into Trump’s efforts to quash affair allegations in 2016.

Here’s the latest in the Brexit showdown.

2020: “Intestinal fortitude”

Joe Biden says Trump has “no intestinal fortitude” to take on gun legislation.

The New York Times asks if Corey Lewandowski has a shot in New Hampshire.

POLITICO wonders why black voters seem to be gravitating toward two white septuagenarian men.

Does Joe Biden want to be doing this?

What happened to Kirsten Gillibrand’s campaign?

The AP looks at a California experiment in universal basic income.