Home care calendar for Ontario and Rancho Cucamonga: wind, fire, pollen, rain and holiday lights

The year at a glance

Weather numbers are NOAA NCEI 1991 to 2020 monthly normals for Ontario International Airport. Sunset times are from sunrise-sunset.org for Ontario, CA, 2026 and 2027.

Wind season: October to winter

Santa Ana winds blow mostly from October into winter. Cal OES says the winds typically blow from October to December, and a National Weather Service forecaster it quotes says they do not peak until December. They lift dust, soil and ash, which is why a clean right before the season starts is worth it. The Santa Ana wind guide has the detail, and the ash guide covers cleanup after a smoke day.

This year may be milder. The National Interagency Fire Center issued its outlook on October 1, 2026.

Strong El Niño conditions favor above-normal precipitation this fall and winter, especially from December onward.

That pattern typically results in a below normal number of Santa Ana wind events.

That is a forecast, not a promise.

Fire season: fall is the focus

Heading into fall and early winter, offshore winds become the primary driver of fire activity.

For the South Coast predictive services area in October, near-normal potential remains warranted.

It adds that some potential remains until a widespread significant rain event occurs.

A 2015 KPBS report says Cal Fire has said fire season in Southern California is year-round. We could not open an official Cal Fire page saying so, so we pass that on as reported, not as an official rule.

Fire-season chores that are not ours to do but are worth a line: keep roofs, gutters and the first 5 feet around the house free of debris, and move trash containers and loose items inside on Red Flag Warning days. The National Weather Service issues a Red Flag Warning when critical fire weather is ongoing or expected soon. If you have solar panels or two-story windows, call us after the smoke clears, not during.

Rain: a long dry spell and a wet winter

By NOAA normals, Ontario averages 0.02 to 0.10 inches a month from June to September, then 0.41 inches in October, 0.80 in November, 1.89 in December and 2.57 and 3.07 in January and February. A modeled data set (WeatherSpark) puts the rainless stretch from about April 22 to October 20. Dust piles up on glass and panels through that long dry stretch. See the solar panel cleaning guide and the window cleaning cost guide for how that shapes a plan.

Pollen: spring and early summer

Loma Linda University Health says in the Inland Empire symptoms can start as soon as late February and continue well into summer.

Tree pollen peaks in spring and overlaps with grass pollen, which tends to spike in late spring and early summer.

A second university health article describes Santa Ana winds bringing desert pollen into the region.

We could not find an allergist or university page that gives months for fall weeds, so we do not give any.

A UCLA allergist told LAist the pollen count was at zero in the air quality index during one wind event. The irritation was from ash and particles. Pollen and dust both land on glass. A wash after pollen season, in late spring, is a good use of a plan visit.

Watering and window spots

Sprinkler overspray is the main cause of white spots on windows near Ontario (see the hard-water guide).

Ontario is currently in the Voluntary Stage of the Water Conservation Plan.

The city asks residents to avoid watering lawns between 9:00 AM and 4:00 PM.

The Cucamonga Valley Water District serves Rancho Cucamonga. It lists tips: ensure there is no sprinkler overspray or runoff, no watering within 48 hours after rain, and turn off sprinklers on windy and rainy days. Check your own water supplier for current rules.

Holiday lights: when and what

Our install weeks run mid-November to mid-December: Nov 14 to 20, Nov 21 to 27, Nov 28 to Dec 4, Dec 5 to 12. Takedown is in January. The earliest sunset of the year in Ontario is about 4:41 pm in early December, so lights get the most use in December. Details are in when to put up Christmas lights, what installation costs, permanent versus seasonal lights, securing lights in Santa Ana winds and displays to visit.

A simple year plan

• March or April: windows and solar panels (twice a year plan, 8% off, covers this and the fall visit).
• June to August (optional): a mid-summer visit if you are near a freeway, warehouse or trees, or your solar app shows output slipping.
• September or early October: windows and panels again, before Santa Ana season.
• Mid-November to mid-December: Christmas lights. January: takedown.
• A plan every 3 months (15% off) puts these on a calendar so you do not have to remember. See plans, or get a price. Selling your home? Read cleaning windows before you list.

TV jobs and the calendar

TV mounting is a year-round job. Many people book it around the holidays, and the TV guides cover cost (cost), size and height (size and height), above a fireplace, on a patio and Frame TVs and renters.

Common questions

Where this applies

We work in every place within 15 miles of Ontario: Ontario, Upland, Montclair, Chino, Rancho Cucamonga, Claremont, Alta Loma, Eastvale, Pomona, Etiwanda, Chino Hills, Jurupa Valley, La Verne, Norco, Fontana, San Dimas, Diamond Bar, Corona, Walnut, Rialto, Covina, Glendora.

Related services: Window cleaning, Solar panel cleaning, Holiday lights, TV mounting, Plans.

More guides

• Window Cleaning Cost in the Inland Empire
• How Often to Clean Solar Panels in the Inland Empire
• Santa Ana Winds, Dust, Windows and Solar Panels
• Wildfire Ash on Solar Panels and Windows: Cleaning Guide
• When to Put Up Christmas Lights in the Inland Empire

Sources

1. NOAA NCEI, 1991-2020 monthly normals, Ontario International Airport (station USW00003102) “ONTARIO INTL AP, CA US”
2. sunrise-sunset.org, Ontario, CA, January 2027 (sunset times) “Fri, Jan 15... 5:04:22 pm”
3. Loma Linda University Health, "Are orange blossoms causing your allergies?" “symptoms start as soon as late February and persist well into summer”
4. Loma Linda University Health, "Are orange blossoms causing your allergies?" “tends to spike in late spring and early summer”
5. sunrise-sunset.org, Ontario, CA, November 2026 (sunset times) “Sun, Nov 15... 4:46:43 pm”
6. Cal OES, "Impending Santa Ana winds bring increased fire risk," October 14, 2023 “don't really peak out until December”
7. sunrise-sunset.org, Ontario, CA, December 2026 (sunset times) “Fri, Dec 4... 4:41:00 pm”
8. Cal OES, "Impending Santa Ana winds bring increased fire risk," October 14, 2023 “seasonal winds typically blow in from October to December”
9. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “Issued: October 1, 2026”
10. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “strong El Niño conditions and climate -model projections favor above-normal precipitation this fall and winter, especially from December onward”
11. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “typically results in a below normal number of Santa Ana wind events”
12. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “Heading into fall and early winter, offshore winds become the primary driver of fire activity”
13. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “near-normal potential remains warranted”
14. National Interagency Fire Center, Monthly and Seasonal Outlook, issued October 1, 2026 “some potential for fire activity remains until a widespread significant rain event occurs”
15. KPBS, March 9, 2015 (Cal Fire on year-round fire season) “in Southern California is year-round”
16. City of San Diego, Zone 0 guidelines for existing structures, April 2026 (5-foot zone, gutters, Red Flag Warning days) “Keeping roofs, gutters, and the area within 5 feet of a home free of leaves and needles”
17. City of San Diego, Zone 0 guidelines for existing structures, April 2026 (5-foot zone, gutters, Red Flag Warning days) “trash containers should be temporarily moved into a garage, and other loose materials should be brought inside”
18. National Weather Service, Red Flag Warning definitions “NWS issues a red flag warning when fire conditions are ongoing or expected”
19. WeatherSpark, Average weather in Ontario, California (modeled; rainless period April 22 to October 20). “The rainless period of the year lasts for 5.9 months, from April 22 to October 20”
20. Loma Linda University Health, "Are orange blossoms causing your allergies?" “It peaks in the spring and overlaps with grass pollen, which tends to spike in late spring and early summer”
21. Loma Linda University Health, "Seasonal allergy risks unique to the Inland Empire" “the Santa Ana winds bringing desert pollen into the region”
22. LAist, October 19, 2018 (UCLA allergist on Santa Ana irritation) “She noted that the pollen count is at zero in the air quality index”
23. LAist, October 19, 2018 (UCLA allergist on Santa Ana irritation) “You're having an inflammatory reaction to these little irritant particles”
24. City of Ontario, Water Conservation restrictions “currently in the Voluntary Stage of the Water Conservation Plan”
25. City of Ontario, Water Conservation restrictions “Avoid watering lawns, and the like, between 9:00 AM and 4:00 PM”
26. Cucamonga Valley Water District, Water Efficient Tips “Ensure there is no sprinkler overspray or runoff”
27. Cucamonga Valley Water District, Water Efficient Tips “No watering within 48 hours after it rains”
28. Cucamonga Valley Water District, Water Efficient Tips “Turn off sprinklers on windy and rainy days”

Written by Foothill Home Services. Local prices on this page are our own draft rates from the price list the quote tool uses. Where we quote an outside page, the quote is linked in the sources above, and we last checked this page on October 13, 2026. Other outside figures are described as the source reports them.