Mountain West Discussion

[Black Hole]

A coolish day today with a high of just 76F at my place. Cloudy now with some showers firing up. 

[Black Hole]

What a glorious change in the weather. 66F under sunny skies at 1:30 pm  

[IbrChris]

Winter is right around the corner, Peter Sinks fell to 12.1 degrees at 6:15 am the morning of Sept 6th. The record low for Sept is -10 set in 2000.

[Jesse]

Winter is right around the corner, Peter Sinks fell to 12.1 degrees at 6:15 am the morning of Sept 6th. The record low for Sept is -10 set in 2000.

Was yesterday's 12.1 a record low for 9/6?

[IbrChris]

Was yesterday's 12.1 a record low for 9/6?

Daily data only goes back to 2010 but it was the coldest low on Sept 6th during the 2010-2016 period.

 

2010: 14

2011: 34

2012: 28

2013: 41

2014: 30

2015: 14

2016: 12

[IbrChris]

It looks like the data has mostly been migrated to the Utah Climate Center website...https://climate.usurf.usu.edu/PeterSinks/index.php. There's a nice query option for past data.

[Front Ranger]

Got up to 89 today. After a cool August, September is off to a warm start. Can't wait until the first true fall front of the year, day time temps in the 50s.

[Black Hole]

Got up to 89 today. After a cool August, September is off to a warm start. Can't wait until the first true fall front of the year, day time temps in the 50s.

Agreed. We've been hanging around 75-85 the last few days which is tolerable. I've really noticed the cool nights so that has been a plus. 

 

Should see some rain next week but no sign of real cool weather. 

[Black Hole]

Some showers popping up to the west this morning, but nothing much. Looks like a little more organization this evening, but mostly for points NW of my location.

 

Occasional showers possible through Thursday morning and cooler. 

[Black Hole]

.03" last night with some light showers. Still looks like this evening is the best chance for something more substantial. 

[Front Ranger]

First day that really feels like fall. Just 48 with drizzle currently in Boulder.

[Black Hole]

Pretty intense thunderstorm went by to my west earlier. Peak wind gust was 57 mph (recorded at least). A lot of lightning too.

 

Looks like some moderate rain is about to move in now as well. 

[Black Hole]

Fantastic weather here the last day! I've picked up .66" in the last two days with numerous thunderstorms.

 

I even had one at 5 am this morning with dime sized hail, wind, and a lot of lightning. 

 

18z GFS shows it cold enough for marginal snow in 8 days, but I have my doubts, as I should at this point. 

[Front Ranger]

Fantastic weather here the last day! I've picked up .66" in the last two days with numerous thunderstorms.

 

I even had one at 5 am this morning with dime sized hail, wind, and a lot of lightning. 

 

18z GFS shows it cold enough for marginal snow in 8 days, but I have my doubts, as I should at this point. 

 

How often does SLC get snow in September?

 

Historically, we get it 20% of the time here in Denver, but I've only seen measurable September snow once in my 10 years here.

[Black Hole]

How often does SLC get snow in September?

 

Historically, we get it 20% of the time here in Denver, but I've only seen measurable September snow once in my 10 years here.

It is more rare here than there but it happens. I had a trace back in 2007, but that is the only time I have seen it. I also saw a couple inches in early October in 2012 I think. 

 

The earliest on record is about the 17th with 2.2" I believe, but there have only been a handful of times with accumulations. 

[Black Hole]

Additional shower activity building up over the lake this evening. 

[Black Hole]

This is a list of the earliest 10 snowfalls at the airport. Early in the year elevation and exact location are very important and so this list would change if you moved elsewhere in the valley. For example neither of the two snowfalls I mentioned show up on this chart.

http://www.wrh.noaa.gov/slc/climate/slcclimate/SLC/pdfs/Earliest%20and%20Latest%20Measurable%20Snow%20in%20Fall.pdf

[Black Hole]

Models are converging on some potential big rain events in Utah next week. Earlier in the week the remnants from a tropical system will move through Cali, Az, and southern Utah. This may produce significant precipitation, with some models keeping it as far north as my area. 

 

Further, models are now showing a deep trough to my west allowing for strong convection and heavy rain. The ECMWF was particularly dramatic with over 2.5" in one day for SLC. That would be among the wettest days ever if it were to actually happen. The GFS and CMC are in the 1-2" range right now. Regardless of how it pans out, it certainly bears watching. 

[Front Ranger]

This is a list of the earliest 10 snowfalls at the airport. Early in the year elevation and exact location are very important and so this list would change if you moved elsewhere in the valley. For example neither of the two snowfalls I mentioned show up on this chart.

 

http://www.wrh.noaa.gov/slc/climate/slcclimate/SLC/pdfs/Earliest%20and%20Latest%20Measurable%20Snow%20in%20Fall.pdf

 

Nice.

 

The earliest measurable snowfall for DEN is 4.2" on 9/3/61. 

 

For Boulder, it's 9/10/1898. But the most impressive Sep snowstorm by far is 9/17-18, 1971, with 21" in Boulder.

[Black Hole]

Nice.

 

The earliest measurable snowfall for DEN is 4.2" on 9/3/61. 

 

For Boulder, it's 9/10/1898. But the most impressive Sep snowstorm by far is 9/17-18, 1971, with 21" in Boulder.

It seems that was also the same for SLC for its most impressive storm, but that was only 4". That is crazy that it snowed 4" on Sep 3rd. 

[Front Ranger]

It seems that was also the same for SLC for its most impressive storm, but that was only 4". That is crazy that it snowed 4" on Sep 3rd.

Yeah, I'd have to check records but in 2014 we got about.25" around the 10th.

 

The 2000 cold wave that also set records in the PNW was the last major Sep snowstorm here.

[Black Hole]

Yeah, I'd have to check records but in 2014 we got about.25" around the 10th.

 

The 2000 cold wave that also set records in the PNW was the last major Sep snowstorm here.

 

I looked up some of the older ones for Denver and found pictures of the 1961 storm. Looks like it did a ton of tree damage. Since it was over labor day weekend a lot of people got trapped in the canyons camping where even more snow fell.

[Black Hole]

Models holding steady for this weeks storm. Upper level low will cut off to the west which will allow for prolonged moisture flowing into the region. Thursday looks more intense as the surface cold front pushes in along with a lot of energy aloft from vortmaxs and the left exit region of the upper level jet. 

I wouldn't be surprised if we got over an inch by the time this is done. 700mb temps will probably bottom out around -5C so some mountain snow is likely too. 

[Black Hole]

Still looking pretty wet Wed night through Saturday morning. A large amount of variability for how close we are though. ECMWF had 4.7" over the period last night, while the same 00z GFS run had .2". I guess we will see

[Black Hole]

I think warm bias SLC will have a below normal September for the first time since 2006. We are slightly above normal now (~ +.5F) but we will have some big time cool days with the storm coming in which should erase that and give us a moderate temperature deficit. Friday especially may have a high in the low 50s which is about 25F below normal.

 

Still looking at some potentially very heavy rainfall. I think 1-3" storm totals seem likely across the area.  

[Front Ranger]

I think warm bias SLC will have a below normal September for the first time since 2006. We are slightly above normal now (~ +.5F) but we will have some big time cool days with the storm coming in which should erase that and give us a moderate temperature deficit. Friday especially may have a high in the low 50s which is about 25F below normal.

 

Still looking at some potentially very heavy rainfall. I think 1-3" storm totals seem likely across the area.

Awesome. Been a pretty boring, warm month here.

[Black Hole]

.20" overnight at my place. Up in Logan they got over an inch. They also had a severe storm with 61 mph winds and very heavy rain. I see .09" fell in 1 minute, not bad. 

[Black Hole]

I've picked up .29" so far with some hail and strong winds earlier. Crazy storms just to my north with a peak wind gust of 81 mph, golf ball sized hail, and heavy rain per reports. 

 

Craziest thing was that there was a tornado that damaged some houses. Just 20 minutes or so north of me. 

[Black Hole]

Turns out there were two different tornados yesterday. Both were EF1s and did some damage to houses. Not that common in Utah.

Today was cold. My high was 48F with rain all day. I've had 1.10" on the day and counting, storm total of 2.18". Probably another 1/4" tonight before it all winds down.

Looking ahead I have a warming trend but I might see some more rain or storms in a week or so. 

[Black Hole]

I ended up with 2.44" for the storm and 3.19" on the month. My low this morning was 42.7F so that was also the coolest so far this fall. Good amount of snow on the mountains with the snow level bottoming out between 7-8k feet.

Looking ahead we may see some thunderstorms on the 29th and some more widespread rain near the 2nd. A few models have been hinting at snow in the longer range. We will see.

[Dan the Weatherman]

I ended up with 2.44" for the storm and 3.19" on the month. My low this morning was 42.7F so that was also the coolest so far this fall. Good amount of snow on the mountains with the snow level bottoming out between 7-8k feet.

 

Looking ahead we may see some thunderstorms on the 29th and some more widespread rain near the 2nd. A few models have been hinting at snow in the longer range. We will see.

 

When does your area have its average first snowfall (trace or greater)?

[Black Hole]

When does your area have its average first snowfall (trace or greater)?

The airport is November 8th, but I would imagine for my house it is probably late October.

 

There has been a first snow as early as mid September or as late as mid December so it really depends on the pattern. 

[Black Hole]

I had a little thundershower 2 days ago and its been nice weather since. Upper 70s with patchy cumulus. 

Looks like some additional shower activity tomorrow. Monday-Wednesday looks dramatically cooler with rain and low snow levels. Looks like snow levels will be just above the population areas briefly, but we could see some flakes mixed in. 

[Black Hole]

Lots of storms around the area tonight. A few tornados in Idaho and a 74 mph gust in the SLC area. Here I didn't get much, but I saw a lot of lightning at least.

Could be close to snow tomorrow morning with a vigorous cold front tonight. 

[Black Hole]

Didn't end up with much more precip behind the front but the cold air arrived just fine. Low of 39F at my place this morning, Provo was 32F. 

[Front Ranger]

Coldest lows of the season here this AM. Low of 34 at DEN, 36 in my backyard. Friday morning we should have our first freeze.

[Black Hole]

Tonight will probably be my first frost. 42F right now with a dew point of 32F and clear skies.

 

We had a few thunderstorms today with some graupel so that was nice. High of 57F. 

[Front Ranger]

I think we'll see quite a few lows in the 20s tonight. Already down to about 40 here.

[Black Hole]

Another relatively chilly night last night with a low of 36.8F at my station, high of 67F. It has been nice. Looks a bit warmer the next few days and sunny. Looks colder and wetter in the long range. 

[Black Hole]

I think we'll see quite a few lows in the 20s tonight. Already down to about 40 here.

What did you end up seeing? What is average for you right now?