I have zoomed in and cropped the image below. There is still a pronounced boundary to the heavy precipitation area. The precipitation scale is the same as in the earlier image in my last post. This is from a shorter range, high-resolution model. I think Flagstaff ends up in the 3/4 to 1 inch range. Notice that another boundary is forming along I-40 to the east. Stay tuned! There will be areas of Arizona receiving large amounts of precipitation over the next few days.
Watching the GFS animation for the next 7 days this morning, I noticed a curious flow in the precipitation pattern. This flow reminded me of our last interaction with the remnants of a hurricane. Hurricane Norbert’s moisture missed us by traveling barely south of us. Next up for us are the remnants of Hurricane Odile. Currently, Odile is hitting Baja Mexico. Model predictions call for Odile’s moisture to move across most of Arizona. But, this morning’s GFS model for NOAA shows that a thin line might separate seriously wet areas from damp areas. We will have to keep watching to see where the water goes.
In the image below, I have added a yellow arrow to show the movement of precipitation. There is a large difference in the amounts to the southeast of the line and to the northwest of the line.
The newest 6-10 and 8-14 day precipitation outlooks show wet conditions continuing. We should be dry today and Friday. There is a chance for showers over the weekend and into early next week. Sometime in the second half of next week, tropical storm, soon hurricane, Odile will deliver more moisture to Arizona.
Mother nature decided to blow the forecast away. There was a ton of moisture in Arizona’s atmosphere. Below is an image from Intellicast.com that shows an estimate of daily precipitation based on radar imagery. If you compare this image to from the National Weather Service, you can see that things didn’t turn out to forecast. The bulk of the moisture hit to the south of Flagstaff. The dry area shifted much farther to the west from the forecast in that image. Still for the summer we are way ahead on precipitation. Also, it doesn’t look like the monsoon season is quite finished, yet.
We will be entering another wet period this weekend. It will last through the first half of next week. The moisture is a result of an Eastern Pacific hurricane named Norbert. Norbert is tracking up the west coast of Baja Mexico. This morning, Norbert is west of the southern tip of the Baja Peninsula. Below is an animated GIF of the GFS Model for the next 4 days. It shows 24-hour predicted precipitation in daily intervals. You can see Norbert in the animation. He’s bringing plenty of moisture to Arizona.
Reinforcing my post from yesterday. The Climate Prediction Center released their new September outlook. We are looking at above average precipitation. Add to this the 6-10 and 8-14 day precipitation outlooks, and they have painted a very wet picture for us this month. Moisture is already flowing our way. Look for thunderstorms to start tomorrow and go through the middle of next week. We may have dry days mixed with the wet days.
We had a wet and cool August. The National Weather Service in Flagstaff published their monthly report for August. Northern Arizona was cool and wet. The wet piece probably surprises no one. The part I find interesting is that the cool temperatures and above average precipitation prevailed in most of Northern Arizona. Too often, we have a bimodal summer. Flagstaff had 2.2 inches over the average precipitation, and 3.8 degrees below normal. I usually think +/- 2 degrees is in the normal range.
The monsoon season may have one more wet session in store for us. As tropical systems continue to march up the West Coast, they may bring more moisture to are region. This weekend is the next big chance.
On Thursday, the Climate Prediction Center released new 1-month and 3-month long-range outlooks. They point to continued above normal precipitation for September, and September to November. They are below. I think the above average temperature waters off the West Coast and the Gulf of Mexico. El Nino continues to look iffy. Currently, another slightly drier period is coming next week.
Apologies to my readers. I missed all the action last week. I was in Germany when many areas had deluges on Monday and Tuesday. The videos on YouTube are remarkable.
In my last post, I pointed out that a drier period was ahead. What I had meant, and what the models foretold, was no rain for a week or so. That has not been the case. Thursday evening, a storm moved across the west side of Flagstaff dumping heavy rain across the area. Friday evening a storm hit central Flagstaff. I got about 1/3 of an inch of rain. I got more rain on Saturday, a mere 0.03 inches. This is drier than earlier in the week when I received over an inch.
This dry trend will continue for the next few days with a 30-60% chance of rain each day through Thursday. I think that in wet years, the forecast models run on the dry side, especially at long lead times. In dry years, they run on the wet side. The result is that more is on the way for this week.
It’s hard to believe since it rained all night last night, but another break in the action is ahead. The weekend might be a bit wet, but next week is looking mostly dry.
I think this is due to the repetitive formation of hurricanes off the coast of Central America. These storms keep forming and rolling off to the west. This pattern shifts the monsoonal flow. I haven’t checked the exact numbers for Flagstaff, but we probably surpassed the average precipitation total for August with this current storm.