A Hokie Stormchase three-fer on Wednesday May 23rd

Wednesday May 23rd started early near Denver CO and ended at sunset in western NE with a lakefront view. Inbetween the Hokie Stormchasers intercepted three separate storms that each provided interesting scenes.

Starting out in Greeley CO before lunchtime we dropped south toward the Denver airport. Convection was already firing when we clambered into the vans and that early trend continued. At one point after we’d sat by the side of a rural lane for a while I checked my watch to find that it was only 12:45 pm. That’s pretty early to begin a chase!

As storm #1 matured we relocated eastward several times, stopping to view the developing dynamics. At this vantage point it really ramped up, exhibiting anticyclonic rotation as a wall cloud built.

storm #1 trying hard

From here we leapfrogged a few miles east and then pushed a bit north to see this view. We couldn’t tarry long here as the hail core was fast approaching.

storm #1 after it ramped up

After this stop storm #1 moved northward into unchaseable territory in northern Colorado (no roads) but we’d already noted more convection firing to the east. So we jumped on I-76 and motored northeast to get ahead of this new activity. Per the radar view an apparent boundary was moving north-northeastward, separating very dry air from somewhat less dry air (call it a “dry-ish” line).

We had to let a couple of stronger cells go as they too entered the unchaseable realms but then storm #2 developed just behind us. We pulled off the interstate at the Crook CO exit and watched as this storm grew in size and strength a couple miles west of us.

storm #2 near Crook NE

As storm #2 chugged northward we were buffeted by strong winds that we at first thought was outflow but then decided they were from the rear flank downdraft – RFD – on this storm. We were dowsed by blowing dust for several minutes.

storm #2 outflow or RFD

As storm #2 continued northward the Hokies observed the hail shaft on the back side of the updraft.Hokies watching a hail shaft at the rear of storm #2

As this cell drew away from us we gave chase, hoping to slide northeast to the intersection of I-76 and I-80 in Nebraska and then jump back west to keep up with the storm. But as we rolled along yet another cell ramped up east of storm #2 and became our next storm.

Taking the Big Springs NE exit we drove a few miles north and found a spot from which to observe storm #3. It cycled through several wall clouds as we watched, developing features tantalizingly close to the ground several times.

storm #3 overall view with wall cloud underneath

It came close to putting something down on the ground but never quite made it. The shear and moisture were both just a bit shy of the levels needed to drop a tornado.

storm #3 view of one wall cloud cycle

To keep up with this cell we moved further east and then north again to the dam on Lake McConaughey NE where we ended the chase. Further north from this point the Sand Hills have few roads or vantage points so it was a pleasant place to pull off, stretch our legs, grab some food from the coolers, and kibitz with the myriad other chasers who had stopped here.

Oh, and did I mention the views of the storm and the lake as the sun set?

can you believe this view

sunset after storm #3 left us in the dust

It was a very relaxing way to end a long day of chasing. We wound up in North Platte NE for the night, a place where several earlier Hokie Stormchase crews have stayed over the years.

 

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Hokie Stormchasers May 22nd

Tuesday May 22 2018 proved less spectacular than previous May 22nd’s for the Hokie Stormchasers as that has historically been a tornado intercept day. However this year the date pretty much met our expectations. The setup didn’t hold a lot of promise for chaseable storms as most of the convective focus was very near and west of the Rocky Mountain front range.

Starting out from Ft. Morgan Colorado we drifted up to Sydney Nebraska in an attempt to hedge our bets to reach a couple of potential target areas. Sydney happens to be the headquarters of Cabelas and the area surrounding those headquarters has a nice park where we stopped for lunch and to watch for convection. Lunch for some of us involved a visit to the fanciest Subway restaurant I’ve ever eaten in. It’s located inside a two story log cabin and has a railroad caboose parked just outside.Sydney NE stop

During this stop a number of the crew also came away with Cabelas ballcaps from the headquarters store.

As things developed we chose to dive back south to intercept storms coming north – once again! – from the Denver area. Driving south and then west on state and rural routes we wound up on this cell.Colorado storm and Rockies

The storm wasn’t anything spectacular but the views were…and yes, those are the Rocky Mountains in the background.

As this complex moved northward it also developed updrafts to the east, causing us to relocate several times to stay out of the precipitation. At this stop the main storm was even closer to the Rockies as trajectories were taking the action to the north-northwest.Road and storm

We wound our way along more roads to keep an eye on the easternmost cells as they developed but nothing else of note occurred. We wound up punching through a weak precipitation core to get to a hotel in Greeley Colorado where we were greeted by an evening supercell that fired and passed just to our west.IMG_9474

Photos really didn’t do it justice as (a) it was too close to show structure, (b) the evening light was fading, and (c) the awesome lightning display was the best part.

Today we’ll likely target somewhere in the eastern WY / southwestern NE / northeastern CO area. That target will be refined in our morning meeting.

Hokies catch a Colorado tornado

The Virginia Tech Hokie Stormchasers saw a verifiable tornado on Monday May 21st, albeit weak and short. After choosing to head north out of Dumas TX we spent roughly 5 hours on the road to Limon CO to intercept a storm that intensified over the eastern Denver suburbs.

Finding a spot just off State Route 86 northwest of Limon we pulled off to park and snap photos and videos. Limon storm

Shortly after this photo was taken a dust whirl appeared on the horizon underneath a small visible funnel…thus a tornado occurred! Several folks captured images of the swirl and my dashcam captured it in all its weak glory (sped up video is posted on the Virginia Storm Chasing FB page). It lasted 25-30 seconds but it counts as a tornado, thankfully occurring in an open area.

However this cyclic storm, which buffeted us with increasing inflow winds every time it ramped up in intensity, treated us to some amazing cloud sights which included an awesome mammatus field. Here’s just one photo of what we saw:mammatus_2

An additional treat was a tremendous lightning show from another storm as we traveled north to our hotel in Fort Morgan CO.

Tuesday brings another chase day!

A May 18th awesome “almost” for the Hokies

During the morning forecast meeting in Guymon OK the Hokie Stormchasers decided to motor into central Kansas. The parameters, forecast discussions, and short range models all pointed to late afternoon discrete storm initiation that would quickly congeal into a messy squall line. Hence the thought was we needed to jump on a storm as it went up and before it joined the squall line parade.

As it turns out so often while storm chasing the forecast discussions and models had to basically be thrown out the window. Outflow boundaries spewed out by late night and early morning convection changed things considerably. After spending some time at a municipal park in Garden City KS we wound up at a spot roughly 40 miles south of I-70 watching updrafts struggling to grow. The upper level cap was strong and held down development for a while.

From a spot a bit further north we kept an eye on two storms, one to our north and one to the west. The northern storm was beautifully lit by sunlight but struggled to keep growing:

last view of storm before heading north

Meanwhile the western storm caught our attention as it looked to be splitting into two storms with separate updraft bases and two precipitation shafts:splitting storm to the west

Relatively suddenly, however, the northern storm began to grow and show signs of rotation. Naturally we dove north to the interstate and pushed east quickly to keep up. However we ran out of exit options and wound up punching directly through the RFD cut on the storm. That was not one of the Hokie Stormchasers’ finest moments. We ran through increasing large hail stones that raised worries of shattered windshields and also had to keep a close eye on rotation developing almost overhead. By this time this cell had a tornado warning near Quinter KS.

We got east of the beast and stopped for a bit to catch our breath and take a few photos.jjust after the punch through

And, yes, this is yours truly snapping photos while hanging out the drivers’ side window (photo courtesy of Dave Carroll):me photoing the storm behind us

When the hail neared we pushed further east and found a spot to watch this gorgeous storm:gorgeous tornado warned supercell

We certainly didn’t want the folks living in Quinter to suffer any damage but we hoped this would drop a tornado out in a field where we could see it. The inflow winds were buffeting our backs as we watched this cell approach and it alllmmmooost did it:Hokies watching the funnel spin out

After this we pulled up stakes and literally raced the approaching squall line eastward, pulling off the interstate a couple of times to seek shelter from more hail shafts crossing the road. We wound up overnighting in Salina KS where we’ll figure out where to target today (Saturday 5/19).

Hokie Stormchase 2018 begins

We drove hard and long to find them but find them we did…storms, that is!

After a record 913 miles on the first day out (Wednesday) the Hokie Stormchasers intercepted a couple of storms in southwestern Kansas after several hundred more miles of van travel. This was a “bonus” day in that anything we could catch on the second day out of Blacksburg was an extra.

So here are a couple of totally unedited photos from our intercept in the Oklahoma panhandle:

IMG_9316

Hokies checking out some mammatus

DSCF5479

An updraft base with a rotating mesocyclone

IMG_9336

Sometimes the lighting is surreal

Today we’ll be targeting southwestern KS but that’s still TBD in our morning meeting coming up soon.

Stay tuned to @Hokiestorm on Twitter (and of course @vawx) for updates!

 

#vawx A marginal chase on an Enhanced Risk day

To use an oft-quoted phrase: “Well that escalated quickly!” This was the evolution of SPC’s Day 2 convective outlook for today – May 14th –  as a stationary front acted as a highway for northwest flow storms to cross Virginia.

VA_swody2 comparisons

Then this is the evolution of SPC’s Day 1 outlook for today:VA_swody1 comparisons

Amid the text used in describing the mid-morning update in the right-hand panel the SPC used the “D” word (derecho) to describe the potential severe risks. Models showed a strong MCS rounding the top of the ridge across the Midwest and diving southeastward across Virginia.

All this was heady stuff for mid-May but I was almost convinced to not chase today. (Derechos aren’t my idea of a desirable feature to chase.) I did finally pull the trigger just in case discrete cells fired along the southern flank of this activity and was rewarded with such a storm that went severe warned just north of Amherst. The arrow is pointing at a Three Body Scatter Spike (TBSS) which is indicative of large hail.IMG_9257

Unfortunately this cell rooted on the slopes of the Blue Ridge and refused to move east over the Piedmont where I could actually intercept it. I scrambled around on rural roads until I finally found a spot north and west of Dillwyn VA from which to observe this most annoying storm and switched on the livestream.later view of severe storm

When this activity weakened I pulled up stakes and headed for home as the MCS/Derecho bulldozed across northern Virginia and headed toward Richmond. All in all I consider it a successful chase but not very satisfying.

 

#vawx Quiet out west? Stay here longer and chase

I just may squeeze in one more May chase before heading out to the Great Plains with the Hokie Stormchasers. Given the dismal weather pattern out west this week the departure has been delayed from tomorrow (Monday) to Wednesday. Meanwhile a stubbornly persistent stationary front is wavering across portions of northern Virginia. The proximity of that front to plenty of heat and humidity convinced the SPC to issue this Day 2 convective outlook for tomorrow:VA_swody2

Most models are showing an MCS (mesoscale convective system) crossing the Ohio valley Monday morning, following the boundary into Virginia. Ahead of that system several WRF models are showing strong convection near or north of the U.S. Route 460 corridor tomorrow afternoon.

The actual location of the front on Monday morning plus the latest runs of short range models will determine tomorrow’s initial target. I may start out along either the Rte 60 or Rte 460 corridor depending on storm trajectories and speeds plus road system and available visibility. I’ll make that call in the morning.

#vawx Four storms, shelf clouds, a hail shaft, and a pollen blizzard today

A quick review of today’s chase begins with the SPC Slight Risk that I suspected would be posted for today:VA_swody1

I picked up my chase partner at 12:30 and we motored to Bedford where we stopped for a bit to decide where to go. Given the east-northeast rapid trajectory we rolled east via U.S. Route 460 to Concord (east of Lynchburg) where we turned north on rural roads to find a decent vantage point. We encountered a shelf cloud there from storm #1 but were forced to flee soon due to outflow winds and approaching rainfall.

While pushing east and south back toward Rte 460 we drove through what we first thought was dust but quickly realized were billowing clouds of pollen. It was enough to make any allergy sufferer shiver but we pressed onward, finally stopping ahead of the action just outside Appomattox. There we saw this whale’s mouth feature just north of our position accompanied by a little hint of greenage.first storm at Appomattox

This line segment kept developing hail and looked as if it would trap us:

So we dropped south through the town of Appomattox and worked our way back west on rural roads, avoiding another line segment that was intensifying to the south. When we’d escaped the closing trap we realized that we could likely catch the western cell on that southern line so we pushed to Rustburg and diverted southeast to follow the line.

This is a view of the hail shaft behind storm #2:Second storm hail shaft SE of Rustburg

We continued chasing this storm a bit further before calling it off as the storm looked like it was weakening. At that point we rolled southward to Brookneal to refuel and grab some dinner. As we sat at the gas station another storm (#3) began to cross U.S. Route 501 north of us. IMG_9200

Naturally we chose to go take a look so we vaulted north to the Brookneal airport to watch this cell grumble by just north of us:third storm at Brookneal airport

While there we took advantage of the peaceful scene to eat the fine cuisine we’d purchased at the gas station / convenience store:picnic dinner at the airport

When storm #3 passed to the east we pulled up stakes and drove west to Gretna. I thought about calling it a day at that point but yet another severe-warned cell was rumbling toward Lynchburg. Thus we jumped onto U.S. Route 29 north and sped to a vantage point just south of the city.

By the time we got into position storm #4 was visibly weakening but still provided an impressive scene:Fourth storm just S of LYH

From here we bagged it and headed home. Shelf clouds, hail, and pollen blizzards had been the order of the day but it was still an enjoyable time even without wall clouds or other stuff.

#vawx More details coming into focus for Thursday

During last night’s YouTube Hangout Andrew Smith and I discussed the potential for severe weather – and chasing of course! – in Virginia on Thursday May 10th. Since that live video chat the SPC has issued its Day 2 convective outlook and, as expected, the Marginal Risk area was extended across the entire Piedmont region of the Old Dominion for tomorrow.VA_swody2

Several key factors piqued our interest last night including a lee trough setting up east of the Blue Ridge mountains and the weakening cold front itself. Given later runs of short range convective allowing models (CAMs) each of those features seem to fire convection. The resulting two distinct areas of activity are shown on this 4-panel simulated reflectivity graphic at 5 pm Thursday from four separate CAMs (courtesy College of Dupage and Pivotal Weather):

Thurs 5 pm reflectivity quad panel

Assuming both lines develop it’s a bit unclear whether the first line would hinder the strength of the cells along the second one. Logic would dictate that would happen. Hopefully this evening’s model runs combined with tomorrow morning’s HRRR model runs will shed more light on this.

Meanwhile the forecast 0-6 km shear isn’t tremendous (25-30 kts) but the vector is oriented almost perpendicular to the convective axis. That would lead one to believe that these cells could easily be discrete instead of aligning along a squall line. Discrete development could lead to a couple of supercells that could reward a chaser lucky enough to pick the right storm.

Where to target? Since the upper level winds are stronger to the north it may be wise to start out more in that direction than down toward the VA/NC state line. Depending on how the models and the actual atmosphere looks I’ll make that decision tomorrow morning.

#vawx Next up…Thursday?

The next May chase could be as soon as Thursday 5/10 as an upper level short wave trough drags a weakening surface cold front across Virginia. The SPC Day 3 convective outlook shows a Marginal Risk extending west from the axis of the Blue Ridge mountains:VA_swody3

However both the NAM and GFS solutions are indicating decent instability east of the mountains with dew points at or above 60 degrees. Convection will likely fire along the slopes of the Blue Ridge and cells will likely strengthen when they reach the lee trough (typically along the U.S. Route 29 corridor). Here’s the 3 km NAM reflectivity output for 8 pm Thursday:NAMNSTMA_prec_radar_060

Shear is a bit weaker south of the I-64 corridor (further from the trough axis) but the updraft helicity output shows some interesting tracks south of that interstate:NAMNSTMA_con_uphlysw_060

So now it’s a waiting game to see what later model runs look like and to check out the shorter range models to determine timing and target areas.

Given the above I wouldn’t be surprised to see SPC extend that Marginal Risk area – perhaps upped to a Slight Risk – over the Piedmont by the time they issue the Day 1 outlook. Andrew Smith and I will be discussing all this on a Google Hangout this evening (Tuesday 5/8) at 8 pm.