5/22/2015 County Rd. J. Colorado Storms

Been quiet over here lately.  The weather pattern has not exactly cooperated with our trip the past few days, but Friday yielded a photogenic storm northeast of Pueblo, CO. We started the morning in Amarillo, TX, to an overcast and murky sky, but quickly broke into sunshine near Campo, CO. We pitted in Eads, CO for lunch (yummy restaurant there!) and traveled northeast toward Limon, CO where persistent convection was starting to look more interesting.  We caught up with the cell near Hugo, CO, before it crossed north of the warm front into cooler air, causing the storm to weaken. Our sites then turned to the Pueblo area, where new development near the mountains was progged to head into a more unstable environment.  We watched this beauty of a storm for almost two hours before packing up and heading to Burlington, CO for the evening.  Below are some pictures of yesterday.

MISC:  Overnighted at the swankey Burlington, CO, Best Western Plus. Also, I have never been so COLD on a storm chase!

Pileus forms over a developing updraft 

5/18/2015 Pecos, TX Supercell and Coyanosa, TX Flash Flooding

Monday featured a well-mixed boundary layer with dewpoint depressions in the 30F range.  While we did not think the environment was favorable for significant tornadoes, we were still very interested in tracking isolated supercell development rolling off of the Davis Mountains in southwest Texas. After getting on the road, we stopped for a quick lunch in Midland, TX, before travelling to Fort Stockton, TX as an initial target.  Our plan was to get to Fort Stockton and launch a weather balloon from the western edge of the better boundary layer moisture.  We met up with the U.S. Naval Academy field group (led by Drs. Brad Barrett and Gina Henderson) in Fort Stockton in anticipation of the launch.  It was nice to mingle with their group and send up our first successful weather balloon launch from the field!

As we launched the balloon (video below) convection was beginning to form near the Davis Mountains as expected. Our sounding confirmed the suspicion that LCLs were too high for a significant tornado threat. After the balloon made it into the stratosphere, we packed up and headed toward Pecos, TX, where the storm was now maturing into a beastly supercell with very large hail.  We sat southeast of Pecos for several hours watching this nearly stationary storm.  It had some nasty inflow (we measured several gusts over 35 mph) but always seemed to have a strong surface cold pool within a few miles or so from the storm.  In fact, it really never had an established updraft area location.  Nevertheless, it was a very pretty storm and made for easy chasing given the slow storm motions.  

After it was clear the storm was not going to get any "better", we fled north behind the core to get back to the interstate (in hindsight, I should have just navigated the team an extra hour out of the way back toward Pecos).  On the way, we encountered the worst flash flooding I have ever seen in my life a few miles south of Coyanosa, TX. We saw (at least) three vehicles swept off of the road into the rapidly rising water! Hail drifts created dense hail fog as waters continued to rise and roads completely covered with at 4-8 inches of water. We found a high/dry spot and waited the worst of the flooding out, but training thunderstorms were creeping from the southwest and I was worried that things we about to get a lot worse.  We got in a train behind some larger vehicles who went first and created a nice wake for us that we were able to comfortably get through.  I am very happy we were able to get out when we did, because we found out later from the NWS that this area now has over 4 ft. of water covering the road!

I never felt we were in a dangerous position until I saw the increase in thunderstorm activity to the southwest of our location.  It was clear that things were about to get ugly fast. A great reminder to always be aware of flash flooding. It is an often overlooked hazard of severe convective storms

MISC: Overnighted at the brand new Courtyard in Lubbock, TX for the second night in a row.

5-18-2015 Weather Balloon Launch Data

Panorama just southeast of Pecos, TX (looking north)

5/16/2015 Elmer/Tipton EF2 Tornado

Saturday was a rather exciting day for the newbies on Trip 2. Not only did they get to see their first tornado, it just happened to be an EF2 wedge tornado that we watched for 30+ min. and tracked over 30 miles.

Here is the preliminary damage survey report from the local National Weather Service office in Norman, OK:

934 PM CDT SUN MAY 17 2015

...NWS DAMAGE SURVEY FOR 5/16/15 TORNADO EVENT

.ELMER-ODELL-TIPTON-SNYDER TORNADO...

RATING:                 EF-2
ESTIMATED PEAK WIND:    125 MPH
PATH LENGTH /STATUTE/:  35 MILES
PATH WIDTH /MAXIMUM/:   TO BE DETERMINED
FATALITIES:             0
INJURIES:               0 KNOWN

START DATE:             MAY 16 2015
START TIME:             APPROX 535 PM CDT
START LOCATION:         6 SW ELMER / JACKSON COUNTY / OK
START LAT/LON:          34.42 / -99.42

END DATE:               MAY 16 2015
END TIME:               APPROX 645 PM CDT
END LOCATION:           APPROX 3 E SNYDER / KIOWA COUNTY / OK
END LAT/LON:            34.66 / -98.90

SURVEY_SUMMARY: INFORMATION ABOUT THIS TORNADO IS STILL VERY
PRELIMINARY. A LARGE MULTIPLE VORTEX TORNADO DEVELOPED IN
SOUTHERN JACKSON COUNTY OKLAHOMA SOUTHWEST OF ELMER OKLAHOMA AND
NORTH OF ODELL TEXAS... AND MOVED NORTHEAST THROUGH THE FAR
NORTHERN PORTION OF WILBARGER COUNTY TEXAS... THEN BACK INTO
JACKSON COUNTY OKLAHOMA SOUTHEAST OF ELMER. THE TORNADO CONTINUED
NORTHEAST MOVING THROUGH TILLMAN COUNTY FROM WEST OF TIPTON TO
SOUTHWEST OF SNYDER... THEN CONTINUED IN KIOWA COUNTY FROM SOUTHWEST
OF SNYDER TO EAST OF SNYDER. THE DISSIPATION POINT OF THE TORNADO
HAS NOT BEEN DETERMINED YET. THE MOST INTENSE DAMAGE FOUND SO FAR
IS CONSISTENT WITH AN EF2 TORNADO.

.CLEO SPRINGS TORNADO...

RATING:                 EF-1
ESTIMATED PEAK WIND:    105 MPH
PATH LENGTH /STATUTE/:  12 MILES
PATH WIDTH /MAXIMUM/:   50 YARDS
FATALITIES:             0
INJURIES:               0 KNOWN

START DATE:             MAY 16 2015
START TIME:             622 PM CDT
START LOCATION:         5.5 NW FAIRVIEW / MAJOR COUNTY / OK
START LAT/LON:          36.32 / -98.56

END DATE:               MAY 16 2015
END TIME:               642 PM CDT
END LOCATION:           4 NNE CLEO SPRINGS / MAJOR COUNTY / OK
END LAT/LON:            36.46 / -98.42

*SURVEY_SUMMARY: A TORNADO DEVELOPED ABOUT 5.5 MILES NORTHWEST
OF FAIRVIEW IN MAJOR COUNTY AND MOVED NORTHEAST TO 4 MILES NORTH-
NORTHEAST OF CLEO SPRINGS JUST EAST OF HIGHWAY 8 AND SOUTH OF THE
ALFALFA COUNTY LINE. THE TORNADO PASSED ACROSS THE NORTHWEST
CORNER OF CLEO SPRINGS WITH ADDITIONAL DAMAGE IN CLEO SPRINGS
CAUSED BY ADJACENT THUNDERSTORM WINDS. THUNDERSTORM WIND DAMAGE
CONTINUED NORTHEAST FROM WHERE THE TORNADO DISSIPATED TO AREAS
NEAR AND SOUTHWEST OF HELENA IN ALFALFA COUNTY.

EF SCALE: THE ENHANCED FUJITA SCALE CLASSIFIES
TORNADOES INTO THE FOLLOWING CATEGORIES.

EF0...WEAK......65 TO 85 MPH
EF1...WEAK......86 TO 110 MPH
EF2...STRONG....111 TO 135 MPH
EF3...STRONG....136 TO 165 MPH
EF4...VIOLENT...166 TO 200 MPH
EF5...VIOLENT...>200 MPH

Photos of the event (some photos have been contrast enhanced):

Courtesy of Trip 2 assistant Matt Piechota

5/15/2015 Norton, KS to Araphahoe, NE Thunderstorms

Day 1 of CoD Thunderstorm Lab trip 2 set sights on central/western NE for severe storm activity.  The prospects for tornadoes trended down throughout the day, but we were able to latch onto a pretty storm near Norton, KS.  Below is a tonemapped shot of that storm.  Tonemapping can occasionally make a photo *pop*, and I thought that this was an appropriate photo to apply the technique to (not all photos look good with tonemapping).

MISC: Overnighted in Lexington, NE.

5/9/2015 Grinnell, KS Tornadoes

Dad and I left for the plains the previous evening in anticipation of Saturday's severe convective risk. It was clear that there would be severe weather somewhere, but a cold pool from overnight thunderstorms ended up greatly reducing the severe weather potential.  Despite the worked over surface air, severe weather still occurred corresponding to the rather impressive upper tropospheric dynamics in place.  Initially targeting southwest KS, the region was slow to clear and we quickly set our sites on strengthening convection in Colorado (storm motions we not in our favor!).  We stopped near Lakin/Tribune, KS, and met up w/ Walker Ashley (NIU meteorology professor), Stephen Strader (NIU Ph.D. student), and Alex Haberlie (NIU Ph.D. student).  It was Alex's first time to the Great Plains, so of course we gave him a hard time about what he had done to the day's setup.  Keeping the warm front in play, we continued northeast out of Tribune to a very turbulent sky. Whirling eddies, interesting cloud formations, and a warm frontal boundary made for interesting conversation in the car while traveling east toward our overnight destination of Salina, KS.  As luck would have it, a cell formed right on the warm front near Wakeeney, KS and immediately produced a tornado.  It wasn't too long before another (what appeared to be stronger) cell formed in southern Gove county Kansas lifting north toward Grinnell.  It was this cell that we targeted, and it really paid off despite some really frustrating initial views of this storm.  We were caught north in the forward flank of the storm and knew it was producing a tornado, we just could not see it.  Every second that passed caused frustration, as we knew we would be in a great place if the precipitation core would just pass north of I-70.  Eventually it did, and a nice elephant trunk tornado came into view. 

We saw at least 4 different tornadoes, with a few of them occurring after dark north of Grinnell (see one of these tornadoes in my poor quality video below).  It was great to get pops his first tornado, despite the dark and rainy conditions which made photographs extremely difficult.

Overall, it was a great quick trip to the Great Plains and Pop's first tornado experience.  I got to test out some new gear in anticipation of our upcoming Thunderstorm Lab field Trip (CoD Trip 2).

Track our trip on twitter (@gensiniwx ; @cod_stormchase)! 

April Verification and May Forecast 2015

First, let's recap the April tornado activity forecast:

The forecast called for 20% chance of being below average, 40% chance of being average, and 40% chance of being above average. 

April averages 131 tornado reports (1950-2014).  This average is slightly higher (163) if considering only the period 1985-2014. This year, the U.S. tallied 181 preliminary tornado reports during April (calculated using the filtered preliminary tornado reports from the Storm Prediction Center), thus putting us at 138% or 111% of normal tornado reports this month, depending on the averaging period.  For ERTAF, I have been using <75%, 75<=x<=125%, and >125% of normal climatology (based on the 85-14 reports) to classify BA, A, and AA activity respectively.  This is obviously subjective and unimportant, as the atmosphere could really care less how we try to split these categories.  I am going to run with the lower, 111% of normal for April 2015, thus putting the month at average tornado reporting activity.  This aligns nicely with the April forecast for a 40/40 split between A and AA conditions. 

Environmentally, one can see that the atmosphere was much more favorable for severe convective storms this April relative to the previous March post! 

Red pixels indicate negative LI anomalies, which are indicative of an anomalously unstable atmosphere supportive of thunderstorms.  The greatest LI anomalies were found in the southern Great Plains and Gulf Coast areas, coincident with the greatest density of tornado and other severe weather reports. 

So, what's up for May?

Based on the current large scale pattern, dynamical models, analog approaches, and ongoing research, here is my forecast for May 2015:

10% Chance Below Average |  50% Chance Average | 40% Chance Above Average

For those interested, sub-monthly forecasts (ERTAF) are being made weekly (issued on Sunday evenings) and can be found here.

Here is a map of reported tornadoes in the month of May:

Extended Range Tornado Activity Forecasts (ERTAF)

EDIT: 4/29/15 - ERTAF has a new home! http://weather.cod.edu/~vgensini/ertaf/

Can forecasters skillfully predict tornado activity levels 2-4 weeks in advance?

That is the question I am actively engaged in at the moment.  This post is the result of several questions and comments about my latest BLOG post found here:

http://www.gensiniwx.com/2015/03/a-quiet-year-for-severe-weatherso-far.html

I will not focus discussion here on the 'secret sauce' going into the forecasts, so please do not ask.

Instead, I'd like to show the framework I'm currently working with and present verification for previous forecasts. I welcome feedback and discussion on the product presented below.

Introducing Extended Range Tornado Activity Forecasts (ERTAF)!

Here is a table of forecasts I have made so far this year (latest forecast issued yesterday 4/12 at 21:20 UTC):

ERTAF

Explanation of the ERTAF columns:

FCSTDATE -  Forecast date of ERTAF issuance.  Forecasts are issued by 2300 UTC.

FCST2START - Start date of the week 2 forecast. Valid time begins at 0000 UTC.

FCST2END - End date of the week 2 forecast. Valid time ends at 23:59 UTC.

FCST3START - Start date of the week 3 forecast.  Valid time begins at 0000 UTC.

FCST3END - End date of the week 3 forecast. Valid time ends at 23:59 UTC.

CLIMO2 - Average (1985-2014) number of tornadoes for the week 2 valid period.

CLIMO3 - Average (1985-2014) number of tornadoes for the week 3 valid period.

ACT2 - Actual number of preliminary tornado reports for the week 2 valid period.

ACT3 - Actual number of preliminary tornado reports for the week 3 valid period.

PN2 - Percent of normal tornado activity for the week 2 verification (ACT2/CLIMO2).

PN3 - Percent of normal tornado activity for the week 3 verification (ACT3/CLIMO3).

ACT2C - Categorical level of actual week 2 tornado activity based on Forecast Key. 

ACT3C - Categorical level of actual week 3 tornado activity based on Forecast Key.

FCST2 - My categorical level forecast for the week 2 valid period issued on FCSTDATE.

FCST3 - My categorical level forecast for the week 3 valid period issued on FCSTDATE.

VERF2 -Verification of FCST2 based on the Verification Key.

VERF3 -Verification of FCST3 based on the  Verification Key.

Verification Key

Random thoughts:

• Counts of all tornadoes are likely not the best metric. Considering the use of (E)F1+ counts. 
• Environments would be better, but haven't thought much about a verification framework.
• Tornado days (any day with a tornado) may help alleviate tornado count problems and be the best metric to use. 
• Forecasts beyond FCST3 may be possible.
• 1985-2014 at least gives a 30-yr climatological record. Different periods could be used, but the 30-yr mark is neccessary given the weekly periods I am examining. 
•  Better verification forthcoming.  This is quick and easy for now.

I am open to dialog and constructive feedback. 

I have no idea how skillful these forecasts will be, but it's time to start pushing the envelope. This is simple, but seems like a logical place to start. 

Caveat emptor: These forecasts are solely my own and do not represent an official forecast from any corporation or government agency. Please use caution when interpreting the results and respect their origin.

A Quiet Year for Severe Weather...So Far

2015 is shattering severe weather inactivity records.  From 1 January to 31 March, only eight severe weather watches have been issued nationwide (3 TOR watches in Jan., 1 in Feb.; 4 SVR watches in Mar, pending the chance for severe weather across portions of OK and TX today  EDIT 4-1-2015: 6 more SVR watches were issued on 31 March, bringing the Mar total to 10 SVR watches and the yearly total to 14).  Of course, if you ask the residents of Sand Springs or Moore, OK, why this year has been so inactive, you might get a few nasty remarks.  Last week (25th Mar.), an EF2 tornado killed one person in a mobile home park outside of Sand Springs, while another EF2 tornado swept through the town of Moore.  This marks the 5th tornado in the city limits since 1998 and should remind us that it only takes one event to change the perspective of an entire severe weather season for a local community.

However, from a climatological, i.e., accounting, perspective, this season has been oddly calm.  As an example, let's take a look at the number of 2015 tornadoes reported in the U.S. v. the 10-yr average:

2015 accumulated preliminary tornado reports (red line) and the 2005-2014 average (black line).  Image courtesy of Greg Carbin (Storm Prediction Center).

On average, one would expect ~222 tornadoes to occur in the U.S. by March 31st.  Our current tally of 37 puts the U.S. just over 16% of normal for this date.  In addition (as the red bars indicate), a majority of the tornado activity this year has fallen on only 3 calendar days.

From a scientific perspective, it begs the question, "Why?"

Dissecting this question involves the understanding of atmospheric ingredients that are necessary for the formation of tornado producing thunderstorms.  In short, weather conditions that typically cause severe thunderstorms have been in short order so far in 2015 (as I stated in a recent interview to Live Science). Below is an image of the Jan-Mar 2015 lifted index anomaly values vs. 30-yr Jan-Mar normals.  Lifted index provides a quick and easy calculation of whether or not the atmosphere is conducive to thunderstorm activity (positive values indicate stable weather conditions, and thus an atmosphere unfavorable for thunderstorms).

Data provided by NOAA's ESRL PSD; maps by author

Notice the large area of positive lifted index anomalies (blue pixels) across the eastern two thirds of the U.S.

My subjective interpretation of such a stable and non-conducive atmosphere for thunderstorms this year is related to the positive sea surface temperature anomalies in the Eastern Pacific Ocean:

Data courtesy of NOAA's ESRL PSD; annotations are my own

This anomalously warm water has been responsible for driving a semi-permanent area of ridging into the Gulf of Alaska (very similar to the conditions throughout most of the winter months in 2014).  This amplified jet in the Eastern Pacific has forced downstream troughing over the eastern two thirds of North America, helping to drive the cold temperatures found throughout the winter in places like Chicago, Boston, and New York City.  There is also additional recent research from colleagues that suggest our current declared state of ENSO is unfavorable for tornado activity across the U.S. (something that has been speculated for many years).

Speaking of ENSO, I'd like to turn the discussion to extended range prediction of U.S. severe weather activity.  By extended range, I am referring to the sub-seasonal to seasonal time scales (2 weeks to 3 months). I recently met in Washington D.C. with colleagues from around the country interested in this topic, where we shared ideas and methodologies pertinent to such an effort.  Current "official" severe weather forecasts in the U.S. are not issued beyond one week because the time and spatial scales associated with tornadoes make it extremely difficult to forecast beyond a couple of days (let alone 2+ weeks!).  Our goal is not to predict the exact timing and locations of tornadoes like the well-known Storm Prediction Center (SPC) convective outlooks.  Instead, we are interested in predicting U.S. severe weather activity levels (defined by various metrics) at subseasonal to seasonal time scales.  Using new techniques, there is evidence that this can be a skillful endeavor (I will refrain from going in depth with such techniques at this time).  As an example, I provided a sub-seasonal forecast for tornado activity on March 8th, 2015 on my personal Twitter account (@gensiniwx):

Indeed (or as luck would have it!?), no tornado watches were issued in March 2015, a successful 23 day sub-seasonal forecast.  It is important to verify these sub-seasonal forecasts (right or wrong), else there is no way to learn from the good/bad forecasts that will ultimately happen. I am planning on setting up a webpage that will house such forecasts and associated verification, so please be patient as this is a slowly developing process with many interested parties.  

You may be curious to know what my forecast looks like for April 2015.  I provided a 20+ day forecast on my Twitter account on 17 March 2015, that calls for an uptick in severe weather during the 6-16 April period (always give or take a few days when dealing with forecasts at these time scales). I am slightly worried that a mid-month lull in activity could take place, producing some uncertainty in mid-late April forecast.

Overall, I think April 2015 will finish average to above average in terms of severe weather activity (counts/watches/etc.) across the U.S. My confidence/probability breakdown for this forecast is as follows:

20% Chance Below Average | 40% Chance Average | 40% Chance Above Average

Look for a verification post when April 2015 concludes.

10/8/2014 Blood Moon

Treated with a total lunar eclipse early this morning.  I was able to snap a few photos and enjoy the early fall crisp sky before my fingers became numb.  This photo was taken around 6 AM CDT from my backyard in Sugar Grove.

6/23/2014 Cheyenne Ridge Supercell

The Cheyenne Ridge provided initiation for convection on 6/23 in an environment with favorable directional shear and modest instability.  The result was robust development of a lone supercell that initially had a very classic supercelll RADAR appearance. Unfortunately, the updraft was not able to balance the cold pool and the storm became outflow dominant (a great example of this process is shown in the timelapse below).  We enjoyed beautiful high plains scenery with eastward advancing thunderstorms including a neat shot in front of a trio of grain bins (one of my favorite shots of the year).  Great views, great people!

   

6/21/2014 Mound City, SD Severe Convection

6-21 featured a risk for severe weather along a weak convergence boundary in north central SD.  This was the first 'chase' day for CoD Thunderstorm Lab Trip 5, and some of the newbies got spoiled with a great day to observe the atmosphere.  We watched a developing supercell near Mound City, SD, and stuck with this maturing convection the rest of the afternoon/evening.  After cold pools from surrounding convection began to merge, we let the significant severe storm pass the road in front of us and shot north to find large hail.  We were able to measure a 2.6 inch stone near Roscoe, SD at 21:03 UTC.  Enjoy the photos and timelapse below!

MISC:  Overnighted in Ft. Pierre; Now chasing with CoD Trip 5 2014

Beautiful sky near Mound City, SD

6/16/2014 Stanton/Pilger/Pender Tornadoes

A fairly inactive 2014 for tornadoes was thrown for a spin on 6-16.  Piechota and I left northern Illinois by 6:30 AM with a broad target of northeast NE / northwest IA.  As we rounded Omaha, NE,  a Particularly Dangerous Situation (PDS) tornado watch was issued for northeast NE and extreme western IA by the Storm Prediction Center for areas along/near a retreating morning outflow boundary:

URGENT - IMMEDIATE BROADCAST REQUESTED
   TORNADO WATCH NUMBER 303
   NWS STORM PREDICTION CENTER NORMAN OK
   310 PM CDT MON JUN 16 2014

   THE NWS STORM PREDICTION CENTER HAS ISSUED A

   * TORNADO WATCH FOR PORTIONS OF 
     WEST-CENTRAL IOWA
     NORTH-CENTRAL AND NORTHEAST NEBRASKA

   * EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 310 PM UNTIL
     1000 PM CDT.

   ...THIS IS A PARTICULARLY DANGEROUS SITUATION...

   * PRIMARY THREATS INCLUDE...
     SEVERAL TORNADOES AND A FEW INTENSE TORNADOES LIKELY
     SCATTERED LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL EVENTS
       TO 3 INCHES IN DIAMETER POSSIBLE
     SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

   THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
   MILES NORTH AND SOUTH OF A LINE FROM 25 MILES SOUTH SOUTHWEST OF
   AINSWORTH NEBRASKA TO 20 MILES EAST NORTHEAST OF TEKAMAH
   NEBRASKA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
   ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
   TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS.

   &&

 The morning potential for surfaced based supercells was a little unclear, with a fairly large spatial area destabilizing underneath more than adequate deep-layer shear for supercells.  However, by mid afternoon it was clear we wanted to be near Norfolk, NE as cumulus began to bubble along the retreating outflow boundary.  LCLs were manageable in this region for tornadic activity, all we needed was a storm.  The special afternoon weather balloon launch out of Omaha reiterated the enhanced threat of tornadoes given the extreme instability present and the large looping low-level hodographs.  You don't see an observed sounding with a Supercell Composite value over 60 and an effective-layer Significant Tornado Parameter over 10 very often...

June 16th 2014 1900 UTC radiosonde launch from Omaha/Valley, NE (KOAX)

4:24 PM CDT visible satellite and supercell composite!

The aforementioned towering Cu continued to strengthen, but with a rather benign RADAR appearance.  The initial cell was certainly elevated, both by RADAR and visual appearance, but QUICKLY became surfaced based as it began to ingest vorticity rich air near the overnight OFB.  After a few lightning strikes, it was clear this storm was off to the races (you can actually hear us mention this at the very beginning of the video below).

We drifted with the cell southwest of Stanton, NE where a nice clear slot began to develop.  The cell had that 'look' and it was apparent that tornadogenesis was underway.  In perhaps one of my funnier moments, I ran into fellow chaser Dave Ewoldt (I had never met him before outside of social media) and said very calmly, "I think we picked the right storm." Indeed we did.

First tornado near Stanton, NE

As the Stanton tornado began to occlude, we jogged east on Golf Course Rd. as a wedge tornado occluded north of Stanton (see our video below) to reposition for a new developing mesocyclone southwest of Pilger, NE.  We stopped a mile west of NE HWY 15 watching a new developing tornado as the rear-flank downdraft began to surge just to our immediate north (you can see the wrapping rain curtains during this time in the video).  After the surge, the tornado became steady-state headed on a direct course for the town of Pilger. 

Tornado just southwest of Pilger, NE

Tornado entering Pilger with new tornado developing to the east.

 As the tornado headed into Pilger, a second mesocyclone developed and another large tornado formed just east of the Pilger tornado. 

Two strong tornadoes now in progress (one exiting Pilger, the other roughly a mile to its east)

Pilger, NE wedge tornado at the end of its lifecycle

We cut north to Wisner, NE and took HWY 51 east before heading back to the north to see a new developing tornado just west of Pender.  This tornado got large rather quickly and also had a smaller satellite tornado that revolved around the main tornado cyclone.

Beginning of wedge tornado west of Pender, NE

In all, we witnessed 5 tornadoes that occurred in northeast Nebraska from a safe distance, including the unfortunate killer tornado that hit Pilger.  An exciting, but sobering chase day.

6/14/2014 Nocturnal Thunderstorms near Sutton, NE

After a disappointing day of sub-par convection, a northward moving rotating storm emerged near Sutton, NE on the evening of the 14th.  The storm was a bit of a surprise, as it produced a brief tornado northwest of Sutton that we were not able to photograph very well due to our movement and amount of light.  The storm put on a nice lightning display before shrouding in rainfall and moving north of I-80.  Called it quits in Lincoln at the Cornhusker hotel.

Initial diurnal development.  Relatively high LCLs and lack of LL SRH seemed to prohibit tornado development.

6/13/2014 Crook County, WY Tornadic Supercell

6-13-14 featured a strengthening surface low-pressure with marginal dewpoints on the northern high plains.  We (Laura, Walker and I) sat near Devils Tower (Wyoming) watching a strengthening supercell that would eventually become tornadic.  We stopped along WY HWY 24 to watch the surging rear flank downdraft cut a tornadic circulation just to our northwest.  After the supercell began to merge into a multicell cluster, we pushed east to RAP where we met up with Walker's brother and nephews to watch mature convection push into the Great Plains.

Morning surface analysis and target shaded in orange