US Races This Weekend (Sept. 19–20): Philadelphia, Fox Cities, Sioux Falls, Bellingham Bay

The marquee races of this weekend — the Air Force Marathon, Top of Utah, Equinox, Fox Valley and the Santa Fe half — are on the main Sept. 19–20 board, with a final forecast at every start. This page is the rest of the weekend: six races that were not on that list, re-checked against their registration pages on Friday morning.

The gist — Sunday is crowded. Sioux Falls goes first at 6:45 a.m. CDT, Fox Cities leaves Menasha at 7, and three starts land at 7:30 local: the Philadelphia Distance Run half, the Rochester half and the Bellingham Bay Marathon. Saturday has one 26.2, the 45th Bismarck Marathon, starting into patchy fog rather than the rain forecast earlier in the week. The whole Sunday board cooled overnight: Philadelphia is 64°F instead of 67°F and Rochester's rain chance fell from 73% to 40%.

What time does each race start, and can you still get in?

What does the forecast say at each start now?

These are National Weather Service hourly gridpoint values pulled Friday, Sept. 18, at 7:50 a.m. ET — the last full model run before the first gun. Tuesday's numbers are in the right-hand column where they moved.

Which start is actually the wet one?

Not Sunday at all — it is Fox Cities on Saturday. The 10K and 5K at Riverside Park in Neenah go at 9:00 a.m. CDT into rain showers with a 72% chance, after a morning that peaks at 90% around 5 a.m., at 59°F with a 13 mph east wind. The marathon and half, on Sunday, get the better end of the same system: 56°F and 23%.

Rochester was the wettest line on this page all week and no longer is. Friday's grid gives Maplewood Park 40% at the 7:30 gun and 48% for the hours after, at 55°F with a 3 mph east wind rather than Tuesday's 13 mph southwest. That is a different race entirely: a still, cool, possibly damp morning instead of a windy wet one.

Bismarck's turnaround is the largest on the page. Tuesday had a 42% chance holding from 7 through 11 a.m.; Friday has 2 to 3% and patchy fog at 55°F with the humidity still at 100%. Fog does not soak you, but it does mean zero evaporative cooling, so the effort will feel warmer than 55°F suggests.

What should you wear at a 55°F start with a 55°F dew point?

That is the Bismarck, Sioux Falls, Fox Cities and Rochester question, and the answer is less than instinct says. Saturated air at 55–58°F feels cool standing in a corral and warm by mile 3, because sweat cannot evaporate. A singlet or short-sleeve tech tee plus a throwaway layer beats a real jacket every time. Sioux Falls warms only 1°F between 6:45 and 10 a.m., so a marathoner there can stay in that setup to the finish.

Three practical calls for this specific weekend:

• Wind, not temperature, is the Sioux Falls and Fox Cities problem. Both build to 14–15 mph out of the northeast by mid-morning. A loose singlet flaps and chills on the exposed stretches; a close-fitting short sleeve does not.
• Philadelphia is the warm one. 64°F at the gun, 68°F by 10 a.m. and a 59°F dew point means a two-hour half finishes in air that feels warmer than the reading. Shorts and a singlet, and take the early water stops you normally skip.
• Bellingham runs two races in two climates. Marathoners start at 53°F in calm, sunny air out at Lummi and finish near 65°F downtown; half runners start at 55°F and finish around 58–61°F. Same race name, two different kit decisions.

The full bands are in our kit-by-temperature chart, and if you are still deciding which pair of shoes goes in the bag, the shoe rotation guide covers what each pair is actually for.

Which races could close before you sign up?

Rochester is the tightest, and the deadline is earlier than most calendars say: online entry ends 3:45 p.m. EDT Saturday, Sept. 19, not the evening. Sioux Falls closes at 4:00 p.m. CDT the same day, with 23 marathon spots, 7 half spots and 15 in the Sunday 5K left on Friday morning; its two dual-race options were down to 2 spots each.

Fox Cities has already closed online. In-person registration at the expo is the only way in now, with 21 marathon spots, 54 half spots and 16 in the competitive walk still showing. The expo runs at the Community First Champion Center in Appleton, and the Saturday 10K and 5K in Neenah had 63 and 8 spots left. The marathon crosses the 1,600-foot Trestle Trail Bridge and runs more than 7 miles of paved trail through seven Fox Cities communities to a finish at Riverside Park in Neenah, with 20 water stations and seven hours on course.

Bellingham is not closing, it is getting more expensive: marathon $140, relay $260 and half $115 all rise after 11:59 p.m. PDT tonight, with late registration in person at the Four Points by Sheraton on Lakeway Drive Saturday from 1 to 6 p.m. Marathon packet pickup on race morning runs 5:45 to 7:30 a.m. at Lummi Nation School.

Did the Rochester Marathon drop the full distance?

Yes. The event now registers as the Fleet Feet Rochester Half Marathon, 5K and Kids 1/2 Mile, and there is no 26.2 on the entry page. Some race calendars still list a marathon and a relay for Sept. 20; the registration page is the one to trust. The kids' half mile starts at 10:30 a.m. near High Falls.

What if your race is not until October?

Then this weekend is a long-run weekend. The fall marathon countdown shows how many weeks remain for Chicago, Twin Cities, Marine Corps and New York. If this is your first start, read the race-morning checklist tonight rather than tomorrow night. Two starts here sit close to dark — Sioux Falls at 6:45 and Bismarck at 7:30 — so the low-light gear notes are worth a look for the walk from the car. Last weekend's full board is in the Sept. 12–13 list, the dew-point pacing problem is worked through in our Erie preview, and the city-by-city morning reads live on the daily weather page.

FAQ

What time does the Philadelphia Distance Run start?

The half marathon starts at 7:30 a.m. EDT on Sunday, Sept. 20, 2026, at 22nd Street and the Ben Franklin Parkway. The 5K starts at 7:00 a.m. Friday's forecast for the gun is 64°F with a 59°F dew point.

Can I still register for the Fox Cities Marathon?

Not online — that closed. In-person entry at the expo is still available, and Friday's page showed 21 marathon spots and 54 in the half.

What is the deadline for the Rochester half?

3:45 p.m. EDT on Saturday, Sept. 19, 2026, through the event's RunSignup page. The half is $117.60 and the 5K $50.82, fees included.

TL;DR — Six more races, Sept. 19–20. Bismarck Saturday 7:30 a.m. CDT, 55°F and foggy, the 42% rain chance gone. Sunday: Sioux Falls 6:45 at 58°F, Fox Cities 7:00 (online entry closed, expo only), Philadelphia half 7:30 EDT at 64°F, Rochester half 7:30 with rain down to 40% and a 3:45 p.m. Saturday deadline, Bellingham Bay marathon 7:30 PDT at 53°F and sunny with prices rising tonight.

Sources

• Start times, prices, spots and deadlines: RunSignup pages for the Philadelphia Distance Run, Rochester Half, Sioux Falls Marathon, Bellingham Bay Marathon and Fox Cities Marathon, read Friday, Sept. 18, 2026; Race Roster for Bismarck.
• Start and finish locations, course notes: philadelphiadistancerun.com, foxcitiesmarathon.org, thebismarckmarathon.com.
• Weekend race listings cross-checked against halfmarathonsearch.com and findarace.com.
• Forecasts: National Weather Service hourly gridpoint forecasts (offices PHI, BUF, FSD, SEW, GRB, BIS), pulled Friday, Sept. 18, 2026, 7:50 a.m. ET. Tuesday values quoted for comparison come from the same grids on Sept. 15.

By the Race Week Ready desk · Updated Sept. 18, 9:01 a.m. ET