Atmosphere Comparison

[Jim]

The endless chatter of weather.

[Jim]

Flagstaff was warmer and drier than normal in August. Average monthly temp was 3 degrees above normal (2nd warmest) and we were 35/100ths of an inch below normal. We had 2.76 inches of rain, but the new 30 year mean, which went into effect August 1, is 3.11 inches. I thought we might have an above normal month the way we were going, but it got dry for the last 1/3. Not that I really minded.

We start the new water year Today.
2011 WY totals for Flagstaff:

SINCE SEP 1: 20.25 Normal: 21.86 Departure: -1.61 2010 WY: 23.69
SINCE JAN 1: 11.34 Normal: 14.19 Departure: -2.85 2010 WY: 18.98

Seems we didn't do that poorly, given the La Nina, despite the less than spectacular monsoon totals. Still, a lot of the moisture was from Last October and December.

Prescott, which I believe reports from an airport in Prescott Valley, had the second driest August on record, with just 1/4 of an inch falling.
http://www.wrh.noaa.gov/fgz/News/Aug2011_PMR.pdf

Phoenix Sky Harbor didn't even have 2/10th of an inch.

Tucson and SE AZ varies, but is mostly below normal.



I'm not entirely sure when the "official end" to the monsoon is, but I predict an early dry end, and think we have less than 2 week left.

[chumley]

And in PHX August was the warmest month ever recorded. The previous top 5 warmest were all Julys, so the August is unusual.

13 days over 110. Forecast for the next 10 days is still calling for 110-114. It needs to end already.

I'm beginning to think there won't be any more storms in the valley before the monsoon ends and things dry out.

[Jim]

Well, the way the last 10 days went in Flag, I wouldn't be surprised if the monsoon drifts east in the next week and we dry out for fall. Once that happens, we usually get a frost or freeze, so our growing season will be over. Maybe not, though. Unlike the mild 2010, this has not been a warm year for us at night, so 29 at night in a week or two wouldn't surprise me. I can see the Valley being done with the rain. Those temps make me think it already is.

[big_load]

@Jim_H I'm surprised that the numbers for Willcox are so high. Is that station actually up in the Chiricahuas rather than in town?

[Jim]

Don't know. I think it's at their airport, the Cochise County Airport, which is actually on the NW side of the town and I-10. Wilcox probably benefits from storms that build over the Chiricahuas and move to the NW, or some of the other ranges nearby. The Chiricahuas are certainly the largest range in SE AZ and are the wettest, so being close probably helps Wilcox in monsoon season. It's only around 4100', and is pretty far from mountains to have a station in them and still be Wilcox. Basically, all of their yearly precip for 2011 is from this summer.

[chumley]

Wilcox Weather Station: http://hikearizona.com/map.php?QX=1019

[Jim]

Position seems a little off, is that supposed to be at the airport?

Not to turn this into a Wilcox, discussion, but it is a little surprising it hasn't developed like Prescott. It is at a nice elevation to have a decent summer, has mountains nearby, and should have mild winters. With the interstate highway, you would think people might want to go there. When I was there last December, it seemed to be really small and felt like it belonged in NW Texas or eastern Colorado. They irrigate a lot in the area, so it can't just be a water thing. I guess people just prefer Tucson or the Valley.

[chumley]

Position seems a little off, is that supposed to be at the airport?

GPS coords from weather site. Also matches an aerial photo they posted, so I think it's right. Possibly away from the airport to prevent too much pavement from affecting readings?

[chumley]

Torrential downpour of biblical proportions in the valley this morning! :roll: Nice change though. Not sure if it will qualify as a "trace" or just go unnoticed in the official readings today.

[Jim]

Yeah, the radar doesn't even seem to have recorded much of anything.

[Jim]

I just realized it's Labor Day Weekend (not Memorial Day as I mistakenly told someone it was) and that means summer is official over in a non-meteorologic/ non-solar sense. Certainly, in Phoenix, or in Florida, summer is still going strong, but I suspect there are some noticeable differences for the Valley and Sonora Desert dwellers in September, over July and June. September was noticeably different from June and July when I was in Florida. In Flag and on the CO Plataea, summer is definitely coming to an end. Jake will likely miss cool to cold mornings in a couple of weeks (I expect a frost or freeze by the 15th), but he likely won't miss them in 4 months. Why am I posting this? It seem like it was only yesterday that summer got going up here, things warmed up over the cold windy May, and I was in Tucson enjoying (yes, I enjoyed it) 105 degrees. 3 months sure went fast.

[big_load]

@Jim_H Although fall is my favorite season in a lot of places, this one brings regret, since I really wanted to do some alpine hikes this summer. I spent this weekend on the shore of the St. Lawrence River, where the switch seemed to be thrown yesterday, from punishing heat and humidity to cool and dreary. I actually like the cool better, but I could feel the change in everyone around, which made the new red of the sumac harder to ignore.

[azbackpackr]

Scattered rain showers all over yesterday, from the Gila Wilderness to the White Mtns. to Holbrook to Flagstaff (which is the route I drove to get home to Flagstaff.)

Not having paid the slightest attention to the news lately (people have had to explain to me who Bachman and Perry are) I am wondering if there was a "chubasco" or other Sea of Cortez storm that brought more moisture up here, or something from the Gulf?

Incidentally, the White Mtns. a lot wetter than the Flag area during this summer. Too bad it didn't start earlier (I'm thinking about the Wallow Fire).

[Jim]

There's a low moving to the north of us that is bringing some additional moisture northward. It just worked out that you drove through rain on what sounds like most of your ride home. The line set up out over those areas, but plenty of higher locations, near the rim, remained dry.

[azbackpackr]

Yes, and I learned I need new windshield wipers...

It has rained already today in Flag!

[chumley]

Incidentally, the White Mtns. a lot wetter than the Flag area during this summer. Too bad it didn't start earlier (I'm thinking about the Wallow Fire).

This is a good website to illustrate that data. It's best to select "Arizona" as the state and "Last 60 days" or "Last 90 days" along with "Percent of normal". The "observed" shows actual rainfall, but the percent of normal gives a much clearer view of how things are versus where they should be.

You can see that in the last 30 days especially, the central deserts are woefully dry. And yes, the White Mtns have had an above normal monsoon, while most of the rest of the higher-elevations have been below normal.

http://water.weather.gov/precip/

[Jim]

Yes, though accuracy isn't always great. We've had at least one widespread, heavy rain storm around Flagstaff this summer, with radar estimates over 2 inches and rain gauge amounts of over 1 inch, but that site had the rained on area in the less than <1 amount for the 24hr period.

[chumley]

Non-monsoon moisture for the weekend? NWS seems to be setting themselves up for some premature precipitation getting all excited about the way things are setting up for Friday and especially Saturday. I'd be happy to see it happen, but I'll believe it when I see it. I know we're in to September now, but this is an unusual setup for the monsoon, and it's not the typical autumn cold front / low pressure system coming down the west coast either. It's possible that the models just have no real idea how to interpret it?

[kingsnake]

Whatever provides the weather for my Mac I just bought, says possible rain on Friday and Saturday, but I'm with chumley. Especially since my part of Sunnyslope has had .03" the last six weeks ...

[Jim]

Yeah, we got a decent amount yesterday afternoon and evening. I was in Kayenta, and had very dry weather at the same time Flagstaff was getting rained on. I had a nice lightning show on the ride home, and some light rain on my new wind shield. I was surprised to see Flagstaff had 1.07 inches. Some came very heavy and fast, and then there was a slower steady rain for several hours. At the airport, at least.

Case in point for the accuracy of the http://water.weather.gov/precip/ website. As I said, the NWS has recorded 1.07 for yesterday, and with the duration of the rain much of the area probably got that or close. However, zoom in on AZ and on the 24 hour setting and you'll see they have Flagstaff in the 1/2 to 3/4 color code, and the airport recording station is on the divide between the 1/4 to 1/2, and the 1/2 to 3/4 colors. It shows we got rain, and that it was likely widespread over the western Mogollon Rim, but the they seem to be off by 50%, at least. The rain I encountered between Black Mesa and Tuba City was light, so the colors out there could be accurate. It's a fun tool, and I use it, but it isn't really accurate for Arizona in monsoon season.