Return to Humidity

When we left Hays, Kansas, just before dawn this morning, it was already 75 degrees F, down from 99 degrees F the afternoon before.  Fortunately, as we traveled east, cloud cover persisted and the temperature  remained stable.

Even better, by the time we reached Junction City, rain began to fall, persisting throughout our journey across the Flint Hills.  Holding the temperature in the low 70s F, the rain was also psychologically beneficial after almost a month of intense sunshine and dry heat along the Front Range.

Beyond Topeka, however, the sun returned and the temperature gradually climbed into the upper 80s by the time we reached Columbia, augmented by Midwestern humidity as we entered a southerly flow from the Gulf of Mexico.  The moist air will feel good for a few days before I begin to miss the semiarid climate of Colorado. 

A Ridge of Heat

Following a week of stormy weather along the Colorado Front Range and across the Central Plains, an atmospheric ridge will build in by tomorrow, bringing sunny, hot conditions within its expanding dome.  Here in Metro Denver, we expect highs in the 90s F for the next week.

As the ridge, produced by a northward arc of the jet stream, expands across the Plains and into the Midwest, Pacific storm systems will be directed along its rim, bringing thunderstorms to the Northern Plains and Upper Midwest.  Meanwhile, behind the dome, an atmospheric trough (a dip in the jet stream) will bring cool, moist air to the drought-plagued West; while snow is expected at high elevations, strong winds and lightning may actually increase the risk of wildfires across the dry terrain.

Until the ridge shifts eastward, the Southwest Monsoon, a vital source of moisture throughout the Four Corners Region and the Southern Rockies may be shut down.  Let's hope the ridge does not dally. 

Extreme Weather & Climate Change

Weather extremes have characterized most of the U.S. this year.  This week's flooding across the Southeastern States has been record-breaking as some locations have received almost three feet of rain.  Ironically, some of the deluge has occurred in areas that had been plagued by drought for many months.

Farther north, severe thunderstorms with tornadoes, high winds and large hail have repeatedly raked the Great Plains and Upper Midwest.  This weekend, another round of severe weather will develop across the High Plains, moving through the Ohio Valley and the Mid-Atlantic Region over the following days.

Extreme heat, warm oceans and a powerful, unruly jet stream combine to produce these dangerous weather conditions.  More than typical, seasonal storm systems, we are witnessing the effects of a warming climate.  Though its effects may vary over the years, these extreme weather events will surely become more common and efforts to reduce damage and deaths will be imperative. 

Severe Weather on the Plains

From a weather perspective, it is always an adventure to travel across the Great Plains of North America.  This morning, after creeping through heavy rain and dodging thunderstorms in Missouri, I was greeted by a clear blue sky as I crossed into Kansas.  While such an abrupt change is usually encountered when a strong cold front pushes into warm, humid air, the air in Kansas was hot and dry, indicating that I had entered a dome of high pressure.

Indeed, the skies were nearly cloudless until I reached Junction City; from that location, I could see clouds off to the northwest, likely forming along the northern edge of the dome.  Reaching the southern extent of that cloud mass in Salina, I was more captivated by conditions on the ground; widespread damage to road signs, trees and a few ranch buildings looked as if one or more tornadoes had recently raked that city.

While the heat and sunny skies persisted all the way to Hays (my overnight rest stop), the clouds north of my route continued to expand and most of northeastern Kansas is now under a tornado watch; in addition, a line of thunderstorms has formed from southwestern Kansas to the tornado watch zone (erupting along the western edge of the heat dome).  Another spectacular light show is anticipated.

Addendum:  The damage that I witnessed in Salina was due to 113 mph wind gusts associated with severe thunderstorms on June 8. 

Light Show on the Great Plains

Arriving in Hays, Kansas, late yesterday afternoon, I saw a thunderstorm approaching from the south.  After crossing the east side of town, it eventually merged with a large cluster of thunderstorms over Russell, about 25 miles east of Hays.

From my room, I was treated to a broad view of the Great Plains to the northeast and watched as the Russell storms spread northward and eastward.  Once the sun set, the lightning show was spectacular, with some cloud-to-cloud strikes radiating back toward Hays.  Consulting the weather radar, I found that a chain of severe thunderstorms stretched from Wichita, Kansas, to the Black Hills of southwestern South Dakota.  In addition, a mass of storms in northeast Colorado extended the turbulence westward; indeed, as was evident on Flight Aware, cross-country air traffic was funneled north of the Black Hills or south of Wichita.

The light show from this massive band of storms continued late into the evening, well past my usual bedtime.  But one of nature's most awe-inspiring spectacles was well worth a modest loss of sleep. 

 

Konza Prairie Biological Station

Though I have driven past it hundreds of times, I never looked into the history and management of the Konza Prairie Biological Station in the Flint Hills of eastern Kansas until today.  Owned by Kansas State University and the Nature Conservancy, this 3487 hectare reserve stretches across rolling tallgrass prairie, just north of Interstate 70.  Indeed, it protects the largest remnant of unplowed tallgrass prairie in North America.

Established in 1971 and significantly enlarged by the addition of the Dewey Ranch in the late Seventies, the Station is named for the Kaw or Kanza People, who occupied the region before they were forced out during the mid-late 19th Century.  The Konza Prairie is managed by the KSU Division of Biology with the primary goals of conservation, education and research; the latter includes ecologic, hydrologic and geologic studies, including the effects of periodic burning and ungulate grazing (cattle, bison or none).

The Station Headquarters is off McDowell Creek Road (north of I-70), where a trail provides access to the prairie ecosystem.  Information for this post was obtained from the Station's website; your financial support for their research is encouraged. 

Bovine Bathing

As summer-like heat builds across the Great Plains, bovine bathing is off to an early start.  Grazing comfortably on verdant pastures just a few weeks ago, cattle are now gathering at ponds and lakes, seeking relief from the heat and the biting insects.

Partly submerged, they are still tortured by flies around their head and neck.  Fortunately, local flocks of swallows take advantage of the insect swarms, filling their bellies and providing some relief for the cattle.  Yet, the swallows are not immune from attack either; as I witnessed today, prairie falcons may zero in on their flocks, hoping to pick off a swallow for lunch.

Beyond the drama at the cattle pools, I encountered a number of Mississippi kites over Hays, Kansas, my routine rest stop on the Plains.  Tomorrow I complete my journey to Colorado, where a cold front will produce near-freezing overnight temperatures early in the week; that same front is expected to ignite severe thunderstorms across the Great Plains and Midwest. 

New Sheriffs on the High Plains

By early April, it is getting too warm for rough-legged hawks on the High Plains of the U.S. and they begin moving back to their Arctic breeding grounds.  There they will nest on rocky outcrops and feast primarily on lemmings as they raise their young.

In their absence, Swainson's hawks take charge on the High Plains, arriving from Argentina where they spent the winter.  Usually nesting in a solitary cottonwood tree, struggling to survive along a dry stream bed, these raptors prefer open country where their diet ranges from rodents to snakes to insects.  They will occupy the High Plains until early October, when the promise of a perpetual summer draws them back to Argentina, often traveling in large flocks.

Today, I observed several Swainson's hawks on our journey across the High Plains of Colorado and Kansas.  We'll spend the night in Hays and complete our roadtrip to Missouri tomorrow.  Details, if warranted, to follow. 

Heading West

Following a stormy night in Columbia, we headed west this morning.  A steady north wind had brought down clear, cool, dry air behind the storm front, perfect for traveling.

Farther west, in eastern Kansas, plumes of smoke rose from the Flint Hills as the annual burning of grasslands was underway.  Designed to remove invasive plants and to nourish the pasturelands, one wonders about the carbon load released into the atmosphere.

And what wildlife did I encounter today (you might ask)?  Easy: turkey vultures, great-tailed grackles and dead raccoons.  But we did see thousands of cattle!  We'll complete our journey to Colorado tomorrow. 

A Heart of Darkness

Heading east across the High Plains yesterday, my pickup was buffeted by strong, south winds from Goodland, Kansas, to Hays.  Since the air was warm and dry, no clouds raced across the deep, blue sky and I could not readily explain the cause of the intense wind.

This morning, as I continued eastward, those potent winds were still blowing and strands of clouds appeared overhead, all pointing toward the northeast.  These strands thickened and darkened as I entered more eastern regions of the Great Plains, indicating that Gulf of Mexico moisture was being drawn northward by the wind.

Then, as the highway climbed atop the Flint Hills of eastern Kansas, broad views unfolded to the north revealing dark skies that stretched across the horizon, topped by towering cumulonimbus clouds.  This was the heart of the pinwheel-like storm, beneath which heavy rain and probable hail were pelting the ground.  Quite a spectacle from a safe distance. 

The Great Plains Transition

Driving westward across the Great Plains of North America, one gradually leaves behind the woodlands and rolling terrain of the Midwest and Southeast as the climate becomes drier and the rivers smaller.  Eventually, the traveler enters the High Plains Province, where  the landscape is flat, the rivers are often dry and the woodlands have disappeared.  For those following Interstate 70, this transition is most abrupt between Hays (elevation 2018 feet) and WaKeeney (elevation 2450 feet), Kansas.

While the landscape change is obvious, birders will also notice a change in the primary raptors.  The common red-tailed hawks and American kestrels of the Midwest, the Southeast and Eastern Plains have been replaced by prairie falcons, Swainson's hawks (summer) and rough-legged hawks (winter).  Bald eagles all but disappear while golden eagles may grace the scene, especially as one approaches the Front Range.

Indeed, east of the mountains, the flat, High Plains yield to dissected terrain once again, the erosive effect of the Arkansas and South Platte River systems, fed by snowmelt from the Continental Divide.  Riparian woodlands reappear and, along the Front Range urban corridor, red-tailed hawks and bald eagles rejoin the raptor population.

An Arctic Pinwheel

A deep atmospheric trough, currently dipping across the Great Lakes, is producing low windchills and lake-effect snows throughout that region.  Up to a foot of snow has accumulated in some areas and the final totals may be twice that amount, especially in the swaths of higher terrain.

More widespread are the gusty winds that are circulating around the central low, which now sits above northeastern Wisconsin.  Moving counterclockwise, they are pulling in additional moisture from the Mid-Atlantic region and raking the Northern Plains and Upper Midwest with Arctic air.

Here in central Missouri, despite the bright sunshine, the storm's northwest winds are producing afternoon high near 42 degrees F; of course, the wind-chill is at least 10 degrees below the air temperature.  A taste of winter just in time for our Thanksgiving feast!  Happy Holidays to all.

Cut-Off Lows

The series of Pacific storms that have brought flooding rains to Southern California have been produced by "cut-off lows," not energized and driven by the jet stream.  As a result, they have meandered eastward, devoid of powerful winds or strong thunderstorms.

Currently, one of these storms is centered over Kansas and its counterclockwise winds are pulling up moisture from the Gulf of Mexico.  A band of steady rain stretches across Missouri, eastern Kansas and eastern Nebraska, a welcome development for this drought-plagued region.

Meanwhile, another cut-off low is spinning off Southern California, sweeping more rain into that water-logged area.  Unless and until an atmospheric trough drops southward to boost its energy, it will likely arrive here by mid week.  We'll take whatever moisture it brings. 

Crossing a Trough

Heading east across the Great Plains today, I drove beneath bright sunshine from Denver into western Kansas.  The air was dry and relatively cool, consistent with passing through the center of an atmospheric trough, caused by high pressure within a dip in the jet stream.

Meanwhile, south of the trough, thunderstorms, some severe, were marching across north Texas, Oklahoma and Arkansas.  As I approached Colby, Kansas, a band of low clouds stretched across the eastern horizon, demarcating the eastern wall of the trough.  Beneath those clouds, the wind had shifted out of the east and, by the time I reached WaKeeney, dense fog shrouded  the landscape.  Finally, as I descended into Hays (my standard layover site), the fog cleared and warmer, more humid air was moving up from the south.

Tomorrow, as I continue my eastward journey, the trough will have deepened in the West and the storms that plagued the Southern Plains today will have shifted eastward and northeastward.  In other words, I can expect to be driving through rain for much, if not most, of the day. 

Raked by a Northwest Wind

 The latest Pacific storm system pulled out of the Northern Rockies this morning and its strong, counterclockwise winds raked the Front Range urban corridor.  Since we were south and west of the storm's path, the winds were out of the northwest.  Furthermore, since the air was descending from higher terrain, it was devoid of moisture, producing crystal-clear air across the region.

As the storm proceeds eastward, the winds will shift from the north and then die down.  Across the Northern Plains and Upper Midwest, its cold front will encounter warmer air and Gulf of Mexico moisture, igniting thunderstorms.

Here at the base of the Front Range, elevation and wind direction have dramatic effects on our weather.  Today, we escaped the brunt of the storm but did lose a lot of colorful leaves from our trees.  Then again, that was beneficial as well; we don't want leafed-out trees when the first autumn snows arrive.

Toward the Hunter's Moon

Continuing my journey across the Great Plains this morning, I was heading toward the Hunter's Moon; our large, bright satellite was gleaming from the clear, western sky.  Its title, of course, reflects the season in which it appears, highlighting the vital importance of hunting in our evolutionary past, in preparation for the lean, harsh months of winter.  By contrast, hunting is now more of a leisure activity than a necessary one across most regions of our planet.

A half hour after my initial sighting, the moon disappeared behind a cloud bank that stretched across the western horizon.  Within another hour, I was beneath that gray, rumpled overcast, enveloped in chilly air.  It seemed as if the transition from bright sunshine to relative gloom reinforced the message of the Hunter's Moon.

While many of us enjoy winter, we evolved in the Tropics and our collective memory has instilled some trepidation as we face the coming cold and darkness.  We also "know" that it is the culling season, when the old, the infirm and the very young have long been potential victims; we acknowledge that fact in our observation of nature but prefer to think we humans are immune.  

A Cloud of Gulls

On my regular journeys across the Great Plains, I am always hopeful to experience an unusual sighting or, better yet, a true wildlife spectacle (usually avian in nature).  Today's reward came in Abilene, Kansas.

Unfazed by a chilly drizzle and a steady north wind,  a massive flock of Franklin's gulls swirled above the Interstate.  Having summered across the Northern Plains, these prairie gulls are on their way to the western coast of South America where they will spend the winter.

Since they feed primarily on insects, often following tractors as they plow fields or harvest crops, today's weather likely forced them to feed directly on the muddy fields.  In contrast to our persistent drought in Missouri, Kansas has clearly received plenty of rain, as evidenced by swollen lakes and soggy farmlands.  

First Autumn Plunge

The first frost and freeze warnings of the season stretch across the Northern Plains this morning.  Though not especially early in that region, the autumn chill is getting plenty of attention after our long, hot summer.  Here along the Front Range, we awoke to an overnight low of 47 degrees F.

Some might suggest that this early September plunge offers more evidence that global warming is but a liberal obsession.  But a warming climate will not eliminate the seasons and, in fact, might make such "unseasonable" incursions more likely due to an energized jet stream.

Our recovery in Metro Denver will be rapid and we expect afternoon highs in the low 80s F for the next week.  Of course, the longer nights, dry air and high elevation will allow overnight lows to dip into the 50s F but our brief, more intense chill is already ending. 

Spectacle over Hays

Heading back to Colorado today, I set out for Hays, Kansas, my regular, half-way, overnight stop.  I drove beneath cloudy skies for most of the 6-hour trip, encountering intermittent showers along the way.  When I reached central Kansas, sunshine prevailed and the temperature had risen into the low eighties F.

Stopping to pick up a sandwich, I was waiting for the order when I spotted a pair of Mississippi kites circling overhead.  Closer observation revealed twenty of the raptors above the city, perhaps the largest flock I have ever encountered.  Indeed, though most of these kites summer across the Southern Plains, I have never observed them this far north or west.  On the other hand, large flocks are common during migrations and this group was likely beginning their journey to southern South America, where they will spend the winter.

Having seen nothing of significant interest on the half-day drive (turkey vultures were, by far, the most common species) the kites were a special and unexpected treat.  Such is the nature of birding; some of our most memorable sightings are those we least expected. 

Midnight Rescue

Staying in Omaha, Nebraska, last night, I was awakened at midnight by approaching thunder and by a strong, gusty wind that raked the trees outside my window.  I was pleased, knowing that this violent weather indicated the arrival of a potent cold front, dropping from the northwest; it will be this front that eventually expels the severe heat and humidity from the eastern half of the country.

For the next hour, swirling winds, continuous lightning and torrential rain kept me at the window, mesmerized by the atmospheric dynamics.  Once it died down, I went back to bed, knowing that our rescue was at hand.

This cold front, with its associated storms, will push across the Midwest, Mid-Atlantic States and, eventually, the Southeast.  How long the relief will last is uncertain but even a few days of relatively cool, dry air will be more than welcome.