Will permanent lights hold up to Fresno summers?

What do Fresno summers and winters put lights through?

Lights on a Fresno roofline live through both extremes. The National Weather Service office in Hanford keeps a table of Fresno temperature records (opens in a new tab). In 2021, Fresno logged 69 days at 100°F or hotter, the most in that record. The fewest it lists for a full year is 15, in 1956.

Winter is the other side. The same NWS table shows years with as many as 50 nights at or below 32°F (1949), and other years, most recently 2021, with none.

On top of air temperature, a roofline in direct sun runs hotter than the air around it, and late-fall and winter tule fog keeps surfaces damp for days. A good system has to handle all of it, year after year.

What do IP65, IP67 and IP68 mean?

An IP rating comes from the international standard IEC 60529. The first digit is protection against solids such as dust. The second is protection against water. A higher second digit means a tougher water test, but the tests are different kinds of exposure, not just stronger versions of the same one.

For a roofline, IP65 or better on the lights is a sensible floor, since they face rain, sprinklers and hose spray. IP67 and IP68 matter more for parts that might sit in pooled water, like a connector in a gutter. Note that IP68 test conditions are set by each manufacturer, so two IP68 products may not have passed the same test.

What is an operating temperature rating?

An operating temperature range is the span of temperatures a product is designed to run in. It is usually printed on the spec sheet, the product label or the manual as a low and a high figure.

• Compare the high end to a real Fresno afternoon, not just the forecast. Track and fascia in full sun get hotter than the air, and so does a controller mounted on a sunny wall.
• Compare the low end to a frosty January morning. Frost is less of a risk here than heat, but it happens.
• Look for the rating on the controller and power supply too. Electronics are often more heat-sensitive than the LEDs themselves.
• If no range is listed, ask the manufacturer. We could not find an operating temperature range on the JellyFish or Govee pages we checked on October 21, 2026.

Does sun on south and west walls matter?

Yes. In the Northern Hemisphere, south-facing walls get the most direct sun across the year. West-facing walls get the low, hot afternoon sun at the hottest part of the day. Those two faces age outdoor plastics fastest.

• UV fades and weakens plastic. Lenses can yellow and housings can become brittle. Look for a manufacturer statement about UV resistance. JellyFish's Built to Last page (opens in a new tab), for example, says its lights use “UV resistant acrylic” to prevent sun bleaching.
• Exposed wire suffers most. Wire hidden inside a track or under the eave is shaded. Wire draped across a sunny face is not.
• Place the controller in shade if you can. A garage wall, the eave's shadow or the north side of the house is kinder to electronics than a west-facing wall.
• Adhesive and sun don't always mix. If any part is held with adhesive, the sunniest faces are where it's most likely to let go.

What about tule fog and winter rain?

Tule fog is the dense ground fog that settles over the San Joaquin Valley in late fall and winter. It doesn't pour water on the lights the way rain does, but it keeps everything damp, sometimes for days.

• Connectors are the weak point. Moisture finds its way into a poorly seated or unsealed joint. Every connection should be fully seated and, where the product calls for it, sealed.
• Drip loops help. Wire should dip below a connection or entry point so water drips off instead of running into it.
• Keep connectors out of standing water. Gutters and low spots on a fascia can hold water after a storm.
• Use a GFCI-protected outlet. Outdoor outlets should have ground-fault protection, which cuts power if current leaks to ground.

How do you check a specific product?

Marketing pages summarize. The spec sheet or manual is where the real ratings live. Read it for the exact model you're buying.

1. 1Find the exact modelProduct lines change. Get the model number from the quote or the box and look up that model.
2. 2Read the IP rating for each partLights, connectors, controller and power supply can each carry a different rating.
3. 3Find the operating temperature rangeCompare it to a sunny Fresno roofline in July, not just the air temperature.
4. 4Look for UV and outdoor statementsUV-resistant materials, outdoor-rated power supplies and a safety listing from a testing lab.
5. 5Ask what isn't listedIf a rating you care about is missing, ask the manufacturer before you buy.

Two examples of what manufacturers publish, checked October 21, 2026: JellyFish's Built to Last page (opens in a new tab) lists IP67 lights, a 48-volt system and UV-resistant acrylic. Govee's 2 Pro product page (opens in a new tab) lists IP68 string lights and an IP67 control box and power adapter. Neither page we checked listed an operating temperature range.