Saturday, June 25, 2016

The View from Here

Looks like Salt Lake has gotten some much needed relief from the heat as I just pulled up the 2 PM MDT observation from the airport and it's only 77ºF with a dewpoint of 19ºF and winds from the northwest at 12 mph gusting to 18.  That must feel so good.

I'm currently in New York visiting family in advance of the American Meteorological Society Conference on Mountain Meteorology, which will be held in Burlington, Vermont next week.  Although we are warming up here and are expected to hit 90ºF tomorrow, it's been pleasant for my stay so far.

Today I did a hike up Snowy Mountain, which is not so snowy by Utah standards, but at 3899 ft, is the highest peak in the southern Adirondacks and requires about a 2000 vertical foot ascent.  Most of the trail is fairly easy, but the last several hundred vertical feet is your classic Adirondack knee breaker, basically a steep creek bed requiring the occasional "vegetable belay," especially on the descent.  A red trail marker on the tree center left confirms that this is the official route.


Many mountains in the Adirondacks still have old fire towers, which are no longer in use, but are greatly appreciated to provide a full 360º perspective given the dense trees on many summits.  When i was a kid, they still had rangers manning many of these towers looking for fires, and it was always a thrill to finish a climb with a visit.  That always seemed like the ultimate job to me, but fortunately I chose a different career path since we do it all with satellites and other tech these days.


From Snowy Mountain you can see the Adirondack "high peaks", a region encapsulating 46 peaks that were once thought to all exceed 4000 feet, although modern surveys reveal a few of these fall short.  I bagged a large number of these peaks with my Dad, but ultimately gave up the quest when I moved west.  No regrets.  The handful we had left required long misadventures with limited views.


The area around Snowy Mountain ain't Manhattan.  It's pretty unspoiled everywhere you look.  Indian Lake, pictured below, has always been one of my favorite large Adirondack lakes.  There are a few homes and camps, but it's fairly undeveloped and the forest is largely impenetrable.


It's good to be back "in the green."

Thursday, June 23, 2016

It's a Two Horse Race for Hottest June

Here are two ways to look at the temperature for June so far.  In the first, we compare the mean temperature for June 1–22 to similar periods in the past.  This year stands as the hottest such period on record, 0.1ºF warmer than June 1–22, 1918.

Source: NOAA Regional Climate Centers
In the second, we compare the mean temperature for June 1–22 to that of prior Junes (i.e., June 1-30).  The mean temperature for June so far would rate as the 2nd warmest on record, behind only last June.
Source: NOAA Regional Climate Centers
Although there's a cool down on tap for Friday and Saturday, we look to rebound again for the remainder of the month.  It looks like a two horse race for hottest June on record between 2015 and 2016.  My money is on the latter.


Tuesday, June 21, 2016

Heat Waves Are Going to Get Worse

Here are a few temperature "highlights" from yesterday:

  • The Salt Lake City Airport hit 100ºF, the first triple digit reading of the summer.  Was it a record?  Nope.  June 20, 1936 hit 101ºF.  
  • The Salt Lake City Airport also set a record high minimum for the day of 77ºF, trouncing the old record of 69ºF set in 2003
  • Alta hit 79ºF, breaking the old record for the day of 75ºF set in 2007
  • Numerous daily record maximum and high minimum temperatures were set in SoCal, including:
    •  122ºF in Palm Springs, which was 1ºF off their all-time record (123ºF) and also equates to 50.0ºC, precisely half way between freezing and boiling. 
    • 111ºF at Bob Hope Airport (Burbank), tying their June record
    • 125ºF in Needles, setting a new record for June and tying their all-time high (set in 1925 and 2005)
    • 126ºF in Death Valley, a record for the day
People often ask me if such heat waves are what we will be facing with global warming. This heat wave is not the future.  The future is worse.

We are still in the early stages of global warming.  Natural climate variability remains a major driver of extreme events like this (although global warming does tip the scales a bit).  When one looks at projections for the future under a "high-emissions" scenario, things don't get really ugly until the middle to late 21st century.  Gurshunov et al. (2013) provide an illustration of this for the most recent Southwest Climate Change Assessment Report.  They define heat waves as days when the maximum or minimum temperature exceeds that of the hottest 5% of summer days or nights (May–September) in the 1971–2000 climatology.   The heat wave index is the cumulative total number of degrees above the hottest 5% temperature threshold on these heat wave days. 

As shown in the graph below, for either maximum or minimum temperature, a clear long-term upward trend in maximum temperature heat waves over the U.S. Southwest has yet to be clearly detected (brown dashed and solid lines, with the latter representing the 5-year running mean), but there is some upward trend in minimum temperature heat waves.  

Source: Gurshunov et al. (2013)
 Heat waves are, however, projected to increase at an accelerating rate during the 21st century (black lines), with the climb for minimum temperature heat waves stronger than that of maximum temperature heat waves.  Studies examining southern California suggest that today's 100-year event becomes a 10-year (or shorter) event in the latter half of the 21st century.  Minimum temperatures are expected to climb faster than maximum temperature (consistent with the larger heat-wave index above), so the character of heat waves will also change, with less nighttime cooling.  

The graphs above are based on a high-emissions scenario in which we remain welded to fossil fuels for future energy demands.  Heat waves are going to get worse, but how much worse ultimately depends on the energy choices we make today and in the coming decades. 

Monday, June 20, 2016

Hot and Cold in SoCal

Although Arizona got some attention in the lead up to the current southeast heatwave, SoCal felt the heat yesterday too.
Source: Penn State
The temperature contrasts along the coast can be quite remarkable in patterns like this.  This morning at about 10 AM PDT, it was 98ºF at USC and 79ºF in Inglewood.  Out at Oxnard, with a decent onshore flow, it's a cool 69ºF.  Location, location, location.

Source: MesoWest
But perhaps the most remarkable temperature goes to Avalon Catalina Airport on Santa Catalina Island.  The airport is 1578 ft above sea level and above the marine layer.  The 11 am temperature was a whopping 101ºF.  Check out their temperature trace over the last 5 days.  Simply nasty.

Source: MesoWest
In case you are wondering, the average high at Avalon Catalina Airport in June is 67.6ºF.

Sunday, June 19, 2016

Box Elder on Father's Day

I often joke that there's no reason to go to Utah County, but really there's one, and that is the opportunity to hike (or ski) some truly spectacular peaks.  In fact, a credible argument can be made that the peaks of Utah County are more spectacular and beautiful than those of the central or northern Wasatch as they tend to be more isolated, have huge prominence, and have spectacular geology and ecology.

Today we hiked Box Elder Peak from Granite Flat Campground via the north ridge route.  The entire hike is spectacular, although much of the approach is south facing and hot.  Making it more tolerable are the tremendous views of huge ski lines that require full commitment.


Although it is only mid June, the hike is nearly entirely snow free.  The patch below was the largest we crossed on the north ridge and it was about 20 feet long.


Although steep, the north ridge has no real technical concerns, other than this highly intimidating class 2 Hilary Step that of course could be avoided to the left.


Nearing the summit.


View of Mt. Timpanogos from the summit.  Still quite a bit of snow on the primary hiking routes.  Willing to bet the Timp Snowfield will be DOA again this year.


Panorama of the divide with Little Cottonwood.


Father and son shot.


If you are sick of the crowds in the Cottonwoods, here's another reason to tag Box Elder.  Although it was very busy in American Fork Canyon, we saw exactly 2 people on the 10.5 mile hike.  Two people!  

In case you are wondering, the max temperature today in Phoenix was 118ºF., unless they had a spike after 5 PM.  Looks like the overnight low was 85ºF.  Yes, I know.  It's a dry heat...

Friday, June 17, 2016

June 2016 Looks To Be Salt Lake's Hottest on Record

I've been hoping we would avoid extreme heat next week in northern Utah, but the latest model runs are not optimistic.

Below is the 0600 GFS forecast of 500-mb heights from this 1200 UTC this morning through 0000 UTC 22 June (1800 MDT Tuesday).  Pretty much a worst-case scneario for us as the ridge over central North America builds westward across the U.S. Southwest and then northward into the Intermountain West.  



The forecast for Tuesday afternoon shows a core of 700-mb temperatures at or above 20ºC across southern Utah, with Salt Lake City around 18ºC.  

GFS 500-mb height and 700-mb temperature forecast valid 0000 UTC 22 June (1800 MDT Tuesday)
Such temperatures would be a record for that date and time (based on the Salt Lake City area upper-air sounding record) and near the all-time record for the month of June of 19.0ºC.

Source: SPC
Based on what I'm seeing in the extended model forecasts, I think we have a solid shot at the hottest June on record at Salt Lake City.  Although temperatures have been a bit more reasonable for the last several days, the average temperature for the first 16 days of June ranks as the 5th warmest compared to the average temperatures for all of June in the past.  

Source: NOAA Regional Climate Centers
Average temperatures for previous Junes have the advantage of having data from the last two weeks of the month, which are climatologically warmer.  The models show predominantly above average or well above average temperatures for the next week (Sunday might be near average if we're lucky) and suggest that trend will continue through the end of the month, as illustrated by the Climate Prediction Center 8-14 day outlook.

Source: CPC
It could be worse.  You could be in Phoenix.  Here's a comparison of The Weather Channel's forecasts for the two cities.



And remember, there's still about 11 weeks of meteorological summer left...