Storm Close to Amarillo Radar

The MRMS products were a big help in this case being able to look at multiple radars since my storm was right near the radar as depicted in the image below.

The Height of the 50dbz core went above 30,000ft agl, which was a trigger for issuing the warning. The 4 panel product below made the process easier in two ways. First the storm was near the radar and so having a 50 dbz echo core height product that took into account multiple radars was extremely helpful as the local office radar was unable to see the top of the storm. In addition, you could just look at the one screen and see the 50 and 60 dbz core height quickly without having to look through multiple slices of an adjacent offices radar to find the height of these cores.

The MESH and HSDA algorithms below both provided lead time for the quarter size hail that fell 11 miles north of Amarillo at 2236Z. The multi radar aspect of the MESH algorithm also made it easier to use than having to look at an adjacent radar to see the top of the storm. The HSDA is not multi radar and thus there were some limitations with this algorithm for the storm near Amarillo due to the close proximity of the storm to the radar.

Cloud Top Cooling (CTC) did a nice job of showing that convection was really trying to break out in Amarillo’s County Warning Area (CWA). There were numerous cloud top cooling signatures beginning at 20z. The first 50dbz echo reached the ground at 2146z. So it took awhile but eventually the storms overcame the cap and became severe (See image of CTC below).

Jeremy Wesely

EWP Mesoscale Discussion May 23 2220 UTC

A complicated convective scenario continues to evolve over western Texas in an area of weak mid level flow where mesoscale features have been the primary driver for storm motion, storm type, and severe weather type.

Severe supercell storms with all severe weather threats continue to move south southeastward across King and Dickens Counties into Kent and Stonewall Counties.  These storms have a history of tornadoes, golfball sized hail, and 80 MPH winds.  This severe threat is expect to persist as these storms move slowly along a region of high theta-E air with dew points in the low to mid 60s.

Recent radar trends show strong mid level rotation continuing in King County…and there is no current reason to believe that this storm will weaken at any point soon.

Because storm mode is expected to be supercellular for at least the next couple of hours and possibly longer…significant severe threats of all modes should be expected in the path of this storm.  In addition to continuing to travel along this boundary of rich theta-E air…NEARCAST products indicate a region of substantial destabilization in the path of this storm.

To the north, in the AMA area, potential for convection continues to be monitored where considerable destabilization is forecast by GOES-Nearcast vertical theta-E difference product.  A strong outflow boundary has pushed to the north and west of the LBB area storms… which continues to complicate the convective scenario.  Originally…  deeper convection was noted on the Cloud Top Cooling product…and though the echo has struggled to develop…lightning and a severe MESH indicator are now noted within an echo in Potter County.  Convection may continue to increase along the outflow boundary in the next couple of hours…with hail and wind being the main threats.

To the south, in the Midland CWA, convection developed in areas of higher terrain and drifted slowly to the north-northeast.  The strongest storm at this time is moving into Andrews County.  These storms have been moving slowly to the north over an atmosphere characterized by dry air…and though the MESH product continues to indicate a threat of hail in the strongest storms…a threat of damaging wind will likely be the primary threat until the storms reach higher moisture.

- Sears/McCormick

SPORT Flash and Trace Tool Kent Co Texas

On a 4-panel with MRMS Sfc Z, Sfc Vil, and others.

The trace tool was used on upper-left panel and indicated how the flashes increased quickly with the severe storm over Dickens, Kent, and Stonewall counties in the southeastern portion of LUB’s CWA.

Admittingly, the latter 5 min occurred while I was creating the image, etc, so didn’t redo my centroid there, just the zig-zag bad data.

Martello

Still Watching and Waiting in Amarillo…

Ok, well we’ve gotten some recent cloud-top cooling amounts from clouds in Randall County, TX.  Cloud top cooling rates as low as -17C/15 min were observed in Randall County as the outflow boundary moved across the area, as indicated in the image below.

Also, notice the rather distinct theta-e ridge that is still present and extending into Randall County per the LAPS data (image below). We’ll see if these products allow for an appropriate focus and help predict likeliest locations for eventual development.

For LUB’s CWA, Watch Out Garza and Eastern Lynn Counties (SW of Current Supercells)!

Watching for potential development SSW of current supercells over Floyd, Dickens, and King counties to the NE. CTC shows potential. Cirrus anvil across the NE CWA will likely inhibit any CTC effectiveness.

Unfortunately, GOES_CIMSS Nearcast (either E or W) data did not extend further enough east across the LUB CWA to be effective with this event. (see 2030 UTC CIMSS W projection below).

If the Garza area was to develop quickly, the OUN_WRF project indicates 0-1KM SRH to 200-260 m2/s2 which mean environment would be favorable for rapid rotation and potential tornadoes like earlier storms to the north.

We continue to monitor development closely.

Martello/Zimmerman

Tornadic Storm Fires Off Old MCS Outflow Near Floydada, TX

Strong convergence initiated northeast of Lubbock, TX near Floydada in Floyd County.  CTC product caught -16 to -17K/15 min around 18:15 UTC on this storm. Tornado warning was issued 19:21 UTC which resulted in 1 hr 6 min lead time if you had warned initially off the CTC signal.

Initialization in TX Panhandle

Texas panhandle is the area of main focus for the first part of this afternoon. Analyzing CI via the CTC product, as seen below, indicated development was expected to quickly form by 19z.

Image 1 – Cloud Top Cooling prior to CI around 18z.

Image 2 – Cloud Top Cooling at the time of CI over the central parts of Texas panhandle around 1815z.

Image 3 – Vis sat around 1815z, with CI. Vis at 1845z shows the explosion of the storm in the panhandle, with the Cloud Top Cooling product thus providing around a 30 mins lead time.

Image 4 – With the radar products unavailable at this time, using MESH and probability of severe hail to show the development of the storm to severe levels.  The CI on Cloud Top Cooling developed around an hour prior to the MRMS products reaching severe levels.

Daily Debrief: 5/22/13

Due to the GOES-13 outage and not operating in a LMA, GOES-R demonstration products had limited use yesterday. However, the WRF simulated satellite forecasts were utilized.

The WRF simulated satellite forecasts seemed to do pretty well with the placement of the larger synoptic-scale...but not as well with some of the isolated convection...especially across PA.

There was a storm that initiated in the simulated satellite forecasts along Lake Ontario early in the afternoon along the lake breeze and no others until later on past our shift across western NY...this seemed to verify well.


Note from the EWP coordinator:

Action will be in the TX Panhandle and W OK on Thursday for our last operations shift of EWP2013. A mid morning MCS over OK may leave an outflow boundary in the eastern PH. As the upper level ridge axis moves to the east, a more favorable deep layer shear profile will emerge, with a chance for supercells. Large hail will be the main threat, but tornadoes cannot be ruled out. Good opportunities for CI produvt and PGLM product evaluation also exist.

Possible CWAs:  Lubbock, Amarillo, Norman


One more note from me...the following products are unavailable today for the HWT forecasters to evaluate due to the GOES-13 outage: GOES-R Convective Initiation, NearCast, and Sounder RGB Airmass. Products available to the forecasters will be PGLM, WRF Simulated Satellite Forecasts, and Cloud-Top Cooling.

WRF Simulated Satellite at 23 UTC

The WRF simulated satellite image forecast for 23 UTC (top) compared well with the observed IR satellite (bottom) with respect to the mid-level boundary location across Indiana.  However, it did not handle the convection well that formed over PA.  Instead it showed more convection east of the higher terrain across MD and northern VA.

Simulated IR Imagery: 22Z

Simulated satellite imagery from last night's 00Z WRF runs showed strong convection near Lake Ontario in the early afternoon with clearing in western New York during the late afternoon hours.  Convection only sporadically tries to develops until well after 00Z in western New York.

GOES-R Product Update @ HWT - 22 May 2013

Most of the GOES-R products are not in play on the EWP side of HWT today due to the GOES-13 outage. The forecasters are working in Western NY in the Buffalo and Binghamton CWAs.

Therefore, there will be a limited number of blog posts today.

Daily Debrief: 5/20/13 and 5/21/13

With Monday being the "spin up" day and Tuesday a late shift where the Convective Initiation and Cloud-Top Cooling products were not utilized since convection was ongoing, only a few of the GOES-R products had utility in Tuesday's operations. We were hoping for better CI chances the next two days but now with GOES-13 out...the NearCast, CI, and CTC products will not be available until 23 May 2013 around 6Z at the earliest. Here are the highlights of the last two days...

NearCast

The GOES-R NearCast Thte-E trends and instability fields were good.

The NearCast instability products showed that instability was really increasing ahead of the southern Mississippi Valley line between 00-06Z last night...which suggested a prolonged event. The squall line kept going through the southeast and wind damage ended up occurring into central MS.


Convective Initiation

The Convective Initiation product picked up on intiiation potential in between the clusters...higher probabilities.

It appears that the CI product had limited false detections...low probabilities did not tend to develop into 35 dBZ echoes.

The CI product would be helpful when there are outdoor events going on that you are monitoring.

On Monday, the CI product gave a good indication of developing convection along the TX portion of the dryline after storms initiated in OK.


WRF Simulated Forecasts

The simulated IR forecasts showed good  accuracy in the two lines of convection...overall pretty good. 

I felt the IR forecasts were impressive...there was a single line of convection with good placement and it was remarkably similar to what was going on. This was using a 23-h fcst. 


Cloud-Top Cooling

Early on Monday, the Wichita Falls, TX storm had a strong CTC signal and that storm went on to produce baseballs.

It will be interesting to see how the CTC product will work for situational awareness for pulse severe situations.


PGLM

I used the PGLM moving trace tool for situational awareness on a few storms. Maybe during the heat of major outbreak it would take too much time to use...but this remains to be seen.

It does get difficult to assess more than one storm using the moving trace tool.

HWT EWP Status for 22 May 2013: 12-8 pm Shift

Note from the EWP coordinator:

Slight Risk for portions of the upper Ohio Valley and the northeast, with the highest probabilities of severe centered over Ohio. The upper level trough continues slowly eastward, and at least one notable wave is progged to swing around the base. Low to moderate instability is expected as a surface cold front moves through the area. Expect convection to develop by early afternoon, and peak in severe potential during the late afternoon and early evening hours, after which it should tail off in severity. Expecting marginally severe hail (up to 1.5″) and possible wind damage up to 65 mph.

Likely CWAs: Wilmington OH, Cleveland, Detroit, Pittsburgh

The blog will be updated after 12pm CDT with GOES-R posts.

New York, New York

Note from the EWP coordinator:

The NE TX activity was mostly a “wind bag”, with very little hail or tornado threat any more. So we have opted to complete our shift up in the Empire State. Our new CWAs: Albany and Binghamton

Mesoscale Update - 00z WRF Simulated IR and Nearcast

I was very impressed with the accuracy of the WRF simulated IR (top left panel) given that the image valid at 23z is a 23hr forecast and was very close to verifying (second image below). See the two images below.

This NearCast shows a very unstable environment (bottom right image...valid at 0630Z) through the night, which should sustain the convective bow as it tracks across Louisiana. The instability and environment actually seems to improve based on this nearcast model. Will see if this verifies.

 Wesely

EWP2013 Mesoscale Discussion 21 May 2000 UTC

LAPS 2.5 Theta-E advection was strongest from central TX near more isolated/discrete severe storms from Burnet, Brady, to Hamilton Texas and northeast through Corsicana to Clarksville along the Red River Valley. GOES-R cloud top cooling (CTC) and Convective Initiation (CI) forecasts just an hour or so ago indicated the increase in the isolated severe cells over central TX well. However, GOES-R positioning was off, but not too far off regarding the tail end of the linear MCS across north and northeast TX.

CIMSS NearCast Layer GOES Theta-E and PWAT differences did show maximums right where the Brady and Burnet convection in central TX was occurring and handling maximum stripe just ahead of the linear MCS moving east across I-35 further across north and northeast TX.

OUN_LAPS SBCAPE appeared to be well in line with current SPC mesoanalyis real-time values and can be trusted for the next 1-2 hours. During the late afternoon and early evening hours, we expect the linear MCS to continue to progress east with potential for embedded meso-vorticies and weaker tornadoes along the leading edge, while larger discrete supercell storms both ahead across the east Texas Piney Woods and southwest into the eastern Texas Hill Country and central Texas to contain more intense modes. These storms will likely see better inflow of rich Theta-E air from the Gulf of Mexico leading to lower LCLs, and the potential for very large hail and longer track tornadoes, if the tail-end of the upper level forcing from long wave trough over the Plains can extend that far south.

CI/CTC AWIPS2 Loop

Tried to manually loop a 4 panel image of CI/CTC/Radar/Vis and with a 40 plus frame count it was too slow to be useful. It took over 20 seconds for all parameters to load. However, at a frame count of 12 it was much faster and of more use for following trends.

Wesely

HWT EWP Status for 21 May 2013: 2-10 pm Shift

Note from the EWP coordinator:

Moderate Risk again for portions of SE OK, AR, NE TX, and NW LA. Convection will be ongoing in the late morning, and is expected to continue well into the late evening and overnight hours. With better convective initiation opportunities to occur later this week, and to allow for some time in the morning for damage survey activities in Moore, we are opting to capture the later portion of this event.

Likely CWAs: Shreveport, Fort Worth, Little Rock, Tulsa, and Norman

The blog will be updated after 2pm CDT with appropriate GOES-R posts.

Welcome to HWT Week 3

Welcome to week 3 of the HWT. The forecasters are busy trying to get spun up on using all the demonstration products in a short amount of time since storms have exploded over OK earlier this afternoon. Once this takes place, the blog will explode as well. :-)

Forecasters are here from Wakefield, VA, Fort Worth, TX, Huntsville, AL, Upton, NY, and the Norman, OK forecasters will join us tomorrow hopefully. Most of the Norman folks were out completing storm surveys this morning from yesterday's tornadoes...which very may well occur again tomorrow. GOES-R support this week at HWT includes myself (Chad), Jim Gurka, and Lori Schultz.

There have been problems with data ingest earlier...but now things are slowly coming back online.

Since I started this post...a devastating tornado tracked 8 miles north of the National Weather Center. Its a chilling reminder that one of the GOES-R goals is to assist in increasing lead time for tornado and severe thunderstorm warnings.