Models » Stu's Weather Blog

Have to break out the T-model

Models, Northern Arizona Weather, Winter Storms 1 Response »

Dec 022012

Not the Model-T, but my very own weather forecasting model. Some of you may remember the intense accuracy it provided years ago. It just seems to work.Since I don’t have a super computer and years of training and education on developing models for predicting weather, the model has a lot of manual tweaks in it to get it to give decent output. I spend a considerable amount of time just figuring out the inputs and boundary conditions to make it work.

The GFS and NoGAPS models have output similar results to mine for this next week. But the results are inconsistent, run after run. So, I thought it was time to give my model a try. Here is the output. While not definitive and with some variability, my experience points to a reasonable likelihood of some snowfall this week. Unless you are me, you are probably silly to use my model. I would stick with the pros, but I feel pretty good about my historic knowledge. There is a good chance of snow this week. My forecast doesn’t match anything else out there.

Stu’s T-model output for the week of december 2, 2012

If you are a serious meteorologist, you should express no interest in the details of how I work this thing, but you can still send me an email (stu@stu-in-flag.net) and ask. It is a curiosity.

No Snow

Models, Northern Arizona Weather Comments Off

Nov 192012

Looks like the NoGAPs model failed. The current storm track is far to the north. Instead, the Pacific Northwest is getting pretty beat up. The GFS model is forecasting a more southern route for the storm track starting with next week. We will see if that sticks.

This week’s weather will be mostly beautiful! Enjoy!

Which model to believe?

Models, Northern Arizona Weather, Winter Storms Comments Off

Nov 152012

Sorry for missing the first real accumulation of snow for the year. But, I was basking in tropical sunlight last week. Ahhhh.

Early next week we could receive another round of snow, depending on which forecast model is correct. The NoGAPs model forecast precipitation for Northern Arizona on Monday morning. The Navy’s model project a quarter to a half-inch of precipitation for the Flagstaff Area.

US Navy NoGAPs precipitation model for Monday, November 19, 2012. (Update: Sorry, I don’t know where this image went. Now it is gone forever.)

However, this doesn’t match the outlook from the GFS Model at NOAA. This model projects the moisture from the same storm misses Northern Arizona.

GFS Precipitation model for Monday morning, November 19, 2012

Which model is better tuned for this year? Of the forecast websites I routinely use, none are forecasting rain or snow on Monday. We’ll have to wait and see.

Maybe I spoke (blogged) too soon

Models, Northern Arizona Weather, Outlooks Comments Off

Apr 042012

Just when I condemn us to a dry spring, the GFS and NoGAPs Models align around a storm for next week. It’s unusual for both models to align at long time points. In the current case, both are predicting a significant storm around next Wednesday or Thursday. NoGAPs predicts the storm’s arrival 6-12 hours earlier than GFS. We will see.

We have wind on tap for the next few days

NoGAPs precipitation forecast for Wednesday afternoon, April 11, 2012

Storm track could include Northern Arizona for next few weeks (winter outlook)

Models, Northern Arizona Weather, Outlooks Comments Off

Oct 022011

Both GFS and NoGAPS models are predicting a wet, continuously cooler week ahead. AccuWeather has predicted temperatures in the low 30s and upper 20s for Thursday and Friday. The pattern from the last few days for Arizona has been more of a monsoonal flow. With the jet stream dropping down, Pacific storms moving from the west to the east will be responsible for the next few precipitation events.

US Navy NoGAPS model precipitation outlook for 6 hours, Thursday morning, October 6, 2011

NoGAPS and GFS models are in agreement with a wet start to the week. Then, they indicate a bit of a break on Wednesday before the big cold push on Thursday and Friday.

US Navy NoGAPS temperature outlook, 5am Friday, October 7, 2011

I haven’t done a big winter outlook this year. I think we could see a similar year to last year. We have a weak La Nina, a more active, but still anemic, Sun, and a generally cold Pacific. For the winter overall, it will probably be warmer than average, drier than average, with scatter times of heavy snow and very cold temperatures.

Cooler weather after monsoonal weekend

Models, Monsoon, Northern Arizona Weather, Outlooks Comments Off

Sep 302011

Tropical Storm Hilary isn’t going to make it to Arizona. But, we will get a fresh shot of monsoonal flow out of the south. I don’t think we will see large amounts over the Northland. We could see strong thunderstorms and all their elements; wind, hail, etc.

Next up is cooler temperatures and a break from the recent, highly nice, unseasonably warm temperatures. The look out for the next two weeks has turned to colder forecasts. The National Weather Service has posted a nice slide today discussing the threat of frost and the average date of frost for multiple locations in Northern Arizona. We are clearly in the zone. Here is my post on Fall Freeze Probabilities.

Also, somewhere over the horizon another storm system will brush Arizona. But, this doesn’t look like the long-term trend. Unfortunately,a mostly dry, winter weather pattern could be taking a set.

6-10 day temperature outlook - Climate Prediction Center

Tricky weather ahead

Models, Northern Arizona Weather Comments Off

Sep 282011

The out look for this weekend keeps shifting around. I feel pretty confident that Hurricane Hilary will not make it to Arizona as an organized storm. But, the storm track is dipping farther to the south, and a system may move across Northern Arizona and draw the moisture from Hilary to the north. But, the models keep shifting.

I think the best bet is to plan on temperatures to start to drop as we get closer to the weekend. Also, at some point over the weekend or early next week, rain showers and thunderstorms will show up. It’s very hard to say how much rain. I am starting to doubt that we will see significant precipitation totals. Over the horizon, it looks like there is at least one potential repeat scenario.

Interestingly, my Shark Oil Barometer is showing a hint of cloudiness today. The photo below will update through the day.

Shark Oil Barometer

Recent event and next weekend

Models, Northern Arizona Weather, Record Comments Off

Sep 262011

The storm on September 14, 2011, two days after our significant hail event in Flagstaff, brought a tornado to the Peaks. Here is an image from the National Weather Service.

Arizona Snowbowl Tornado - National Weather Service

The NWS in Flagstaff has done a great job in recent history with their documentation of major events like this. Very nice work!

This week we should see awesome weather! Simply beautiful. Sunny, warm days and cool comfortable nights are in store. But, a significant change is still lurking for the weekend. Hurricane Hilary is current off the coast of Mexico. The National Weather Service and AccuWeather are both forecasting Hilary to run up the Baja Coast and bring cooler temperatures and elevated chances for rain this weekend for most of the state. However, I am still not sure it will happen. this morning only the GFS model shows this track. Other models show Hilary drifting about and fading into obscurity.

Summary of computer models from Weather Underground.com

So, this weekend could be cold and wet, or it could be like the rest of the week. One particular point, the GFS model has shown the same behavior for the last week or so. Another particular point is that the NoGAPS model has shown a similar drifting track since Hilary first came into it’s time window. Keep an eye out. I’m going to close the windows on my roof this week.

Will the monsoon of 2011 go out with a roar?

Models, Monsoon, Northern Arizona Weather Comments Off

Aug 302011

The last few weeks have been dry. But, the Climate Prediction Center has a roar in their outlooks. This seems possible with a potential moisture surge from a tropical system coming across Northern Mexico and Texas. Also, another chance for a big East Coast storm, Katia, is on tap for the not to distant future.

8-14 day precipitation outlook from the Climate Prediction Center

Tomorrow came yesterday

Models, Monsoon, Northern Arizona Weather Comments Off

Aug 152011

I recorded a whopping 1.71 inches of rain by my electronic and manual rain gauges yesterday. I think this is the first time they have matched.

We’ll see as more people post their rainfall from yesterday, but it looks like it was a wet one for most of us. The National Weather Service reported 1.08 inches, just 2 hundredths of an inch short of the 1.1o inch record. According to them, that puts us a little over half an inch above average. Which means that in a single day, we went from about half an inch below average, to half an inch above average.

This morning the models are looking wet after Wednesday. The forecasts and models for the next couple days are dryer than yesterday, but things should start back up late in the week.

Older Entries

Switzer Canyon, AZ

Switzer Canyon, Flagstaff, AZ
temp:	71.1 F (21.7 C)
humidity:	14%
wind:	From the SW at 3.6 MPH Gusting to 7.4 MPH
pressure:	30.27" (1024.9 mb)
station:	KAZFLAGS23
hardware:	Oregon Scientific WMR-100a
updated:	May 23, 11:23 AM MST
local forecast