Disclaimer
This site is a reference, not an authority. Here is what it cannot tell you, by topic, and which body can.
Nothing here knows what tomorrow will do
Every climate figure on this site is a long-term average, the 1991–2020 normals for Phoenix Sky Harbor International Airport. An average describes what a day in this month usually looks like. It cannot tell you what today will do, and it does not know that a heat warning, a dust storm warning or a flash flood warning is in force.
For anything happening now, the authority is the National Weather Service forecast and warning for your location. Read it before you read a page here.
Nothing on this site is medical advice, and nothing here can tell you whether a particular person is safe in a particular temperature. Heat risk depends on the individual (age, medication, fitness, hydration, clothing, acclimatisation, and whether they are working in sun or shade) and none of that is knowable from a webpage.
What pages here can do is repeat what the bodies responsible for heat safety publish: the recognised signs of heat exhaustion and heat stroke, and the instruction to call 911 when someone is confused, fainting, or has hot dry skin. That guidance comes from the CDC and from Maricopa County Public Health, and it is repeated with links rather than paraphrased into something firmer than it was.
In an emergency, call 911. Do not look it up here, and do not write to this site. Nothing sent to it reaches an emergency service.
Activity ceilings shown in the heat tools are this site's own working bands, chosen inside the National Weather Service heat-index categories. They are labelled as the site's judgement on the pages that use them. They are not an official scale and they are not a medical assessment.
Pages here repeat what Maricopa County Flood Control District and the Arizona Department of Transportation say about dust storms, flash floods and flooded road crossings, and they report what Arizona law provides on driving into floodwater. They do not advise you about a specific crossing. No page can tell you how deep the water ahead is, what the road underneath it is doing, or whether the vehicle you are in will make it, and the entire point of the guidance is that the answer is unknowable from the driver's seat.
This site is not a legal reference. Where a page states a legal requirement, it says which authority the statement comes from and links to it; for advice about your own situation, consult a lawyer.
Planting dates, watering schedules, citrus care and hydrozone plans here come from University of Arizona Cooperative Extension guidance and from the climate normals. They describe what works in the low desert in a normal year, at the scale of a yard. They do not account for your soil, your microclimate, the age of your trees, or the particular plant cultivar you bought.
Where a page mentions a pesticide, a fertiliser or a pool chemical, the label on the product is the authority: the label directions, the label warnings and the label's restrictions govern, not a summary here. This site does not tell anyone how much of anything to apply, and where an amount appears it is a calculation from the numbers you entered, not a recommendation.
The Desert Plant Picker includes pet-safety information drawn from published sources such as the ASPCA's toxic-plant listings. That information is not veterinary advice, it is not exhaustive, and a plant not flagged here is not a guarantee of safety. If an animal has eaten something, call your veterinarian or a poison control service.
Nothing on this site is financial advice, and nothing here is a promise about a bill. Utility rate structures, plan names, on-peak hours and rebate programmes change, and they differ between providers and between plans. Where a page refers to an on-peak window, it describes a typical structure and links to the utilities' own current plan pages. The plan document, not this site, is the authority on when your electricity is expensive.
Maintenance schedules for air conditioning, evaporative coolers and pool equipment are general guidance. Manufacturer instructions and the judgement of a licensed technician take precedence, and work on refrigerant systems, electrical circuits and gas equipment should be done by someone qualified to do it.
Low Desert Almanac is an independent editorial project. It is not affiliated with, endorsed by, sponsored by or operated by NOAA, the National Weather Service, Maricopa County, the City of Phoenix, the Arizona Department of Transportation, the Arizona Department of Water Resources, AMWUA, the University of Arizona, the CDC, or any other body whose material it uses. Those bodies publish the records and the guidance; this site reads them, explains them and dates its reading.
Where a page here and an agency's own publication disagree, the agency is right and this site is wrong. Please report it so it can be corrected.