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Ski ’til July 4th! Watch Yosemite Fall!

posted on Wednesday, June 22nd, 2011 at 9:28 pm

Reporting on the record snowfall across the western United States convinced me to plan a last minute trip to Mammoth Mountain Ski Resort in early June. I recruited my husband, fellow meteorologist Jonathan Myers, to venture west with me, to take advantage of the late season snow! We ended up flying into San Francisco, (where my sister lives), and had to drive the looooong way around to get to Mammoth because all of the Sierra Nevada mountain passes were closed (due to the record snow). You know how something that seems likes it’s going to be a huge hassle turns out to be a big blessing? That’s the way our trip went. My Mom convinced us to go to Yosemite National Park to see how the record snowfall and melt had enhanced the waterfalls in the park. Yosemite is not that far from San Francisco-about 4-5 hours. We booked a tent/cabin in Camp Curry and drove over.

Camp Curry, Yosemite National Park

Camp Curry, Yosemite National Park

This is a picture of our cabin/tent. They have heated cabins, but since we booked at the last minute, we bundled up with wools blankets and sleeping bags with overnight temperatures in the 30s.  At about 4am, I started asking if we could just get up and go hiking since I was freezing. Everybody finally got up at about 5:15am and we were on the trail to Vernal Falls by 6.

Vernal Falls, Yosemite National Park

Vernal Falls, Yosemite National Park

The hike to Vernal Falls is only about 3 miles round trip. In fact, by 6:40, we only had .3 miles until we got to the top. That’s about 17-18 hundred feet, right? My Mom and I had a little optimistic mid-hike meeting, saying we should go on to Nevada Falls, which is 5-6 miles round trip since we were making such good time. Yeah, no. The last .3 miles is straight up, stairs, with a mist coming off the falls that soaks you from head to foot. You’d be shivering if you weren’t sweating so much from the hike.  Don’t get me wrong. It was beautiful, inspiring, something I’m so glad we did. But, it was not an easy 1.6 mile hike. We did continue about a 1/2 mile more to get this beautiful sunrise shot of Nevada Falls.

Nevada Falls Sunrise, Yosemite National Park

Nevada Falls Sunrise, Yosemite National Park

If I were to do Vernal Falls and/or Nevada Falls again, I would recommend carrying a poncho, water, and snacks! A peanut butter and jelly sandwich with a little coffee would have tasted so good as we watched this sunrise! We were very happy that we got on the trail so early. When we were hiking downhill at 8am, there was a line of summer hikers headed up. It’s punishing to get up before the sun comes up to hike, but it’s worth it when there’s nobody on the trail and you get the sunrise views.

Later, we drove around and looked at some of the other waterfalls, including the famous Yosemite Falls which is the tallest waterfall in the United States. The snowfall over the Sierra this year is 178% of normal, and the output from Yosemite Falls at the time of this picture was 1600 cubic feet per second. It was beautiful.

Yosemite Falls, Yosemite National Park

Yosemite Falls, Yosemite National Park

When we left Yosemite, we had to head back toward the west, then north and then east again because the mountain pass east from Yosemite was closed. If Tioga Pass (Highway 120) had been open, it would have taken us 2-3 hours to get to Mammoth. Instead, it took about 10 hours!!! Thank goodness the views were amazing. As I’m writing this, I’m disappointed we didn’t capture the shot as we rounded the bend on U.S. Highway 50 into South Lake Tahoe and saw the incredible view of the lake, the glacier mountains and the valley floor. It was a very steep mountain pass and there was nowhere to pull over!

As we drove toward South Lake Tahoe, we saw a roadside construction sign that said Monitor Pass was open, so we headed over Highway 89 toward US 395 that would take us into Mammoth. Highway 89 is a remote highway that takes you through Markleeville, California.  More windy roads without guard rails, more incredible, once-in-a-lifetime vistas. There is a bike ride that goes over these mountain passes in the summertime called the Death Ride.

We spent two days in Mammoth. Spring skiing is always a good trip because there are less people on the mountain and it’s warmer. The ski conditions were also remarkable for the time of year. The mountain is open daily until July 4th.

On the way back, we found out Caltrans had just cleared Highway 108 or Sonora Pass. A long and windy trail over the Sierra Nevada Mountain range, it passes US military training camps and freshwater rivers filled with recent snowmelt. The top of the pass still had 10-15′ of snow. Incredible.

Sonora Pass, 9,582'

Sonora Pass, 9,624'

We ran into a German couple right by this sign, we had both stopped to get pictures of the snow. Luckily, we made it to this sign just before darkness fell. It was still a long drive to the bottom of the mountain and the lights of the interstate.

Dawn Brown, FOX 8 New Orleans

Here Comes The Fog Again

posted on Tuesday, February 15th, 2011 at 10:03 pm

After an unusually cold and dry winter so far across the Gulf South, the pattern has taken a more typical turn.  High pressure is building back in, winds out of the southeast are setting up, and warmer temperatures are ushering back in, but also so is dense overnight fog.  As the pattern stagnates over the next several days, reduced morning visibilities can be expected across portions  of the Gulf states.  In fact Dense Fog Advisories have been issued for the coast of Southeast Louisiana for visibilities below 1/4 mile at times.  Cities that can expect slow morning commutes are places like New Orleans, Baton Rouge, and Biloxi.

Dense Fog Advisory February 15, 2011, Image: NOAA

Dense Fog Advisory February 15, 2011, Image: NOAA

What’s the deal with this Gulf Coast fog during the Fall, Winter, and Spring?  Well, its something called sea fog and it doesn’t just happen in Louisiana and Mississippi.  In fact, it also occurs in other places in the United States, like San Francisco, and even in other places around the world, like Hong Kong!

Sea Fog Formation, Image: Hong Kong Observatory

Sea Fog Formation, Image: Hong Kong Observatory

Take a look at the image above.  This is what causes sea fog to form.  Winds from a warm and humid source region blow over an area of colder water.  This helps to condense the moisture out of the warm, moist winds as they pass.  This process forms a low cloud.  Those same winds then push the newly-formed cloud over a nearby landmass and voila: fog.

In the case of the Gulf South, these winds are southeasterly and pick up warmth and moisture from the Central Gulf of Mexico, where the deep waters still have temperatures well into the 70s.  These rather tropical winds then run northwestward over shallower near-shore waters, that are much more subject to cooling by the cold wintertime land temperatures.  These coastal waters have temperatures only in the 50s.  This helps condense the moisture out of the warm, relatively muggy southeasterly winds.  Hence, a bank of low clouds forms.  The southeasterly winds then push that batch of clouds onshore and there you have it: sea fog and rough morning commutes across the Central Gulf states this week.

Pretty “Cool” Ice Photos & Its “Effect” On Lake-Effect Snow

posted on Sunday, February 13th, 2011 at 8:19 pm

Think this winter’s been bad in the South?  Well imagine over 100 inches of snow… every year!  Places like the Great Lakes see it, routinely. You know when you hear about those Christmas or New Year’s reports of 35 inches of snow snarling holiday travel in places like Buffalo, New York?  Well, typically that’s caused by a phenomenon known as lake-effect snow.  Lake-effect snow is caused by an unstable atmosphere (similar to the atmosphere during a thunderstorm.)  In the case of thunderstorms, you have an atmosphere with lots of humidity, warm ground, and a cool upper atmosphere.  Lake-effect snow is caused by cold, arctic air rushing in on cold winds out of the northwest over the relatively warmer (and of course, moist) Great Lakes waters.  Now, of course, you need “water” to get lake-effect snow going.  If there’s ice covering the lake, the water vapor needed for lake-effect snow is not available and the lake basically “shuts down” for the production of lake-effect snow.

The Great Lakes, as you may  know, are very big: hundreds of miles long, tens of miles wide, and hundreds of feet deep, so it’s not likely they’ll all entirely freeze over for any significant amount of time, although it is, on rare occasion, possible that they’ll mostly freeze over, like during the very cold winters of 1976-1977, 1977-1978, and 1978-1979.  Most years, though, most locales on the lakes don’t get a break and get inundated with lake snow all winter long.

In several areas, though: far western New York, northwestern Pennsylvania, and northern Ohio, folks do get a break!  During the coldest months of the winter; it’s typical during many winters, the shallowest of all the lakes, Lake Erie, will nearly entirely freeze over and this nearly closes down the heavy snow machine along its shoreline.

February 8, 2011 Lake Erie Ice Cover, Image: NOAA

February 8, 2011 Lake Erie Ice Cover, Image: NOAA

In the latest February image of Lake Erie taken via satellite above, you can see  there’s lots of white over the lake.  That’s actually a sheet of ice.  The darker black area, in fact, is the area of the lake that has been left uncovered and unfrozen. By far, there’s more ice than water.   Therefore, it’s tough to get much more than lake-effect flurries going.  Earlier in the season, though, before it really gets cold, it’s a totally different story.

January 11, 2011 Lake Erie Ice Cover, Image: NOAA

January 11, 2011 Lake Erie Ice Cover, Image: NOAA

In the satellite photo above, you can see just a month ago, before the long duration of cold… the lake is wide open with plenty of water and water vapor to work with!  This is the season where we see the blizzards along the lake shore.

To check out the forecast in places affected by the lake  freeze-over lull, take a look at Cleveland and Buffalo.

On a side note, take a look at the imagery again and focus on the upper right.  That’s Lake Ontario.  It’s over 10 times deeper than Lake Erie.  You can see, between both photos, there’s not much change in the amount of white on the lake.  Lake Ontario, since its much deeper and contains a larger volume of water, has a much harder time cooling off and, therefore, has a much harder time freezing.  In places like Rochester and Watertown, New York, there’s nary a respite from the lake snow onslaught.

Paralyzing Winter Storms Rank 3 Out of 5

posted on Tuesday, February 8th, 2011 at 10:21 pm
2011 Northeast Storm, Image: NASA

2011 Northeast Storm, Image: NASA

NASA captured this image of the Christmas Blizzard of 2010 on December 28, 2010. (The clouds in the picture have waves, the snow looks like spray paint.) All in all, the system dumped almost 2 feet of snow across metro New York. The storm paralyzed the city, caused thousands of airline cancellations, and led to loud outcries from New Yorkers frustrated with the slow response. And some people just went a little crazy… did you hear the story about the guy who skied behind a car going 40 mph? Here’s the video from youtube if you missed it.

The National Climate Data Center finally came out with its ranking of the storm. There are currently 43 storms ranked on the Northeast Snowfall Impact Scale, the scale ranks storm from 1960 forward. The Christmas Blizzard or “Great Snowstorm of 2010” ranks as #20. (The two storms that followed on January 9-13th and February 1-3rd rank #18 and #19.)

Christmas 2010 Blizzard

Christmas 2010 Blizzard

January 2011 Snowstorm

January 2011 Snowstorm

February 2011 Snowstorm

February 2011 Snowstorm

In 2006, NCDC began ranking Northeast snowstorms based on their impact to the community. The storm is either notable (category 1), significant (2), major (3), crippling (4), or extreme (5). The storm is categorized by the amount of snow, the size of the area impacted and the population of the area impacted. A snowstorm that dumped 30+ inches of snow across portions of the Northeast in 1993 ranks the highest.

The difference between the Northeast Snowfall Impact Scale and the Saffir-Simpson Hurricane Wind Scale (a scale used in forecasting hurricanes), is that the snowstorm ranking is given after the storm hits. It’s not used to forecast the impact of the storm.

The difficulties in trying to forecast the impact abound. Just like determining the track of a hurricane, forecasting the track of a blizzard can be equally frustrating. The entire forecast can depend on the position and strength of the low pressure system in the center of the storm. (Hurricanes are tropical cyclones, blizzards or winter storms are extra-tropical cyclones. Both are centers of low pressure with a counter-clockwise spin. Hurricanes are warm-core systems, winter storms are cold-core systems.) In a winter storm, if the storm weakens or strengthens, or the center of the storm tracks 50 miles north or south, the amount of snow across the metropolitan New York region could range from 1-2 inches to 1-2 feet! In a hurricane, the strength of the low can be the difference between power outages and the widespread devastation.

Currently, forecasters try and determine the impact of a storm by the amount of snowfall and emergency managers response to the storm.  The Northeast Snowfall Impact Scale could eventually be used to forecast the storm in a manner similar to how the Saffir-Simpson Scale is used for hurricanes. It could eventually be used to give emergency managers an idea of how to prepare, how many snow plows and drivers to have on standby, how much water and/or milk you need to buy before you hunker down for the storm.

The south is preparing for yet another wintry mess. Catch the local forecasts in Little Rock, Jackson and Atlanta.

-Dawn Brown, FOX 8 New Orleans

Gulf Low Brings Another Winter Blast

posted on Wednesday, February 2nd, 2011 at 5:38 pm
February 2011 Blizzard

February 2011 Blizzard, courtesy: NASA

Click on the image above twice for a high resolution picture.

Calling it one of the largest storms since the 1950s, NASA turned its cameras toward the Midwestern States Tuesday to capture a winter storm stretching across 30 states. Chicago and Oklahoma City were two of the hardest hit cities. Chicago came to a standstill with its 3rd highest snowfall on record, 20. 2″ of snow fell during the blizzard. Blizzard warnings are issued when winds are expected to reach 35 miles per hour. That is one of the reasons this storm was so dangerous. The other reason was ice on the roadways. Warmer air in the upper atmosphere can support other types of wintry precipitation, such as sleet or freezing rain. Freezing rain is rain that freezes on contact with the surface or roadways.

If you want more information on sleet versus freezing rain, read my previous blog entry on wintry precipitation.

A lot of excitement here in New Orleans, Louisiana, as sleet began falling shortly before noon in our viewing area. The mighty Midwest storm yesterday was a rain and wind event for us, with a line of heavy thunderstorms crossing  before the arctic cold front blasted us with freezing temperatures overnight.

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