How to decide on weather conditions?

[surfer349]

So my question is about weather conditions and traveling for a hike. What do you do to make the judgement call on a hike/overnight trip? Just look up the zip code? For example, I live in Phoenix area, but want to do some over night hikes around Rim country and the Superstitions. How do you check for localized weather conditions, flash flood risks, etc?

Hell, it can be monsooning @ south mountain but sunny and dry across the highway in chandler.

[joebartels]

zoom into any area on the map
- right click over the map or tap menu on mobile
- select forecast
- jump, scream or dance at leisure

I'll typically check the trailhead, destination, high & low points.

If you are heading out soon or on location....
In the lower left corner of the map is radar & rain. Both loop time animation by default. You may click any of the timings to freeze animation.

[chumley]

@surfer349
The right-click option Joe suggested is pretty accurate when trying to determine the temperature where you will be.

Judging precipitation forecasts is much more of a shot in the dark. Monsoon storms behave differently from winter season storms for instance. One thing that is typically true is that there will be a higher chance of rain or snow once you get into mountainous regions. A 10% chance of rain might still put you in a dangerous thunderstorm with lightning and hail and flash flooding. A 90% chance of rain might leave you dry all day.

Many storms that hit Arizona also affect one part of the state more than another. Forecasts can show the potential for this and you can plan accordingly. For example, if Yavapai County is forecast to get hit hard, the White Mountains or southeastern sky islands might be relatively storm-free.

The National Weather Service issues flash flood watches when forecast conditions support the possibility of flash flooding. Sometimes flash floods can happen even though no watch was issued, so you can't ignore what you see outside just because something wasn't forecast. A flash flood warning is issued when flooding is already happening or imminent. This isn't usually helpful since you are already out in the woods somewhere with no connectivity to that kind of communication.

Generally if I think it's going to rain, I'll just add the appropriate gear to my backpack. Once I canceled a trip due to forecast rain ... Antelope Canyon. That's the only time I recall letting the forecast actually make me stay home. Other times I've adapted based on conditions. Don't camp in a creek bottom or strand yourself on one side of a wash with no possible exit if you think it could flood. Common sense goes a long way.

[Alston_Neal]

@joe bartels
Is that just the coolest thing or what. I was just telling my beloved what a pain searching weather for an area was.

[SpiderLegs]

I just wait to see what Chumley forecasts for the weekend.

[chumley]

I just wait to see what Chumley forecasts for the weekend.

I'm gonna stay on the safe side and just predict there will be some posts in the forum that will make you .

I haven't even considered looking at what the weather might be like yet.
:GB:

[sschloss]

If you have an Android phone, you can get the unofficial NOAA weather app. Open the map, pick any point anywhere in the US, and you get the forecast specific for that location and elevation including precip probability and temperatures. I use it all the time.

https://play.google.com/store/apps/deta ... free&hl=en

[toddak]

After 10+ years here, I'm more and more of the belief that AZ weather must be very difficult to forecast and that the predicted chance of precipitation is almost always overstated. Anything less than 50% I consider to be essentially zero, only after 80% do I start believing. Unless I'm headed into a slot canyon, I usually ENJOY getting wet anyway, knowing that it will probably clear up and be sunny and warm soon after.

[big_load]

@toddak
I agree that AZ weather is much less predictable than some other places. The precipitation chance isn't always off in the same direction, though. Once I started a backpacking trip with a 30% chance in the afternoon of the first day, and 20% or less after that, only to find myself in a howling three-day storm within six hours.

[chumley]

Anything less than 50% I consider to be essentially zero, only after 80% do I start believing

I think that's truer in the valley than once you get into the higher terrain.

In fact, on the Mogollon Rim or White Mountains in July, it's almost the opposite in my experience! A forecast chance of 20% is a near guarantee that you will see a thunderstorm overhead by early afternoon!

[SuperstitionGuy]

I just look at the weather 50 miles north, south, east and west of my hike location and plan for the worst. Just sayin... ;)

[JasonCleghorn]

Phoenix has the 3rd most predictable weather in the US behind Honolulu and San Diego.

[nonot]

Weather is probabilistic, and to get a good idea of the probable weather you should get, you actually want to look at many different forecasts. With various news sites, weather webpages and whatnot you can collect about 30 different forecasts for a particular area. This gives you a reasonably good breakdown of the weather you will likely get.

e.g. 1 site predicts all day storms, 5 say chance of storms, and 16 say maybe a drizzle, and 8 predict no rain, then it will likely drizzle on you with a small chance of getting heavier rain.

I only do this on ultra-long trips where the weather may prevent me from doing part of the trip on a given day. Most days I bring a poncho because that's all you need for 99% of arizona trips.