EWP Blog

The MESH 120 min track shows the storm split over Reeves and Ward counties in SW TX very well.  Probably should post this under the “Geeking Out” category.

0015z OUN-WRF Updraft Helicity

0055z OUN-WRF Updraft Helicity

New towers going up western Guadalupe and San Miguel Counties being watched closely for cooling cloud tops around -15C/15min.  If growth rate increases slightly, may need additional SVRs for this area shortly. Last minute report just came in of 1 inch hail with warned storm over eastern Guadalupe County southeast of Santa Rosa.

Garmon/Dutter

Had to issue a new warning to account for a left moving storm in eastern Lea County, NM. 3DVAR did not pick up any sign of the antimesocyclone, which is not easily seen in the low levels.  Should the updraft helicity or more likely, helicity show negative values for cases like this?

Update: we also missed the right moving split from the western storm. Would not want to be the warning forecaster in MAF. Notice the splits in the MESH tracks.

Strong convection has finally initiated over southeastern New Mexico. Storms are exhibiting splitting characteristics as they move toward the South Plains. Again, the latest OUN WRF seems to have a good handle on location as storms move into the southwest part of the CWA.

The Cloud Top Cooling was rather impressive with the cells that increased in severity over Lea County NM. Cloud top cooling rate was above 30 degrees C/15 min in northern Lea County. Close to issuing severe thunderstorm warning for Yoakum County but left movement of storm causing some hesitation at the moment.

Tim/Ty

Earlier had nickel size hail reports near this storm with MESH of 0.8 inch.  Values approaching 1 inch we issued a SVR for Mora county.  Just got a report of a high based rotating wall cloud near this storm.  Broad rotation on KFDX NexRad. At 2350Z the MESH increased to 1.3 inches.

Garmon/Dutter

These images from MRMS should make it clear: these storms are twin terrors of terrible hail.

60 to 67 dBZ to -20C and max MESH values of 2.0 to 2.5 in. Gabe was showing us some nice storm chaser video feeds of the updraft. We put tennis ball size hail in the warning.

Update: Looked at 3DVAR fields for these storms and updraft just increased to 21 m/s with the western storm.  Strong inflow around 17 m/s seen by 1km 3DVAR winds too.

Trained spotter at 700pm reported golfball size hail.

0700 PM     HAIL             LOVINGTON               32.95N 103.35W
06/12/2012  M1.75 INCH       LEA                NM   TRAINED SPOTTER

SNELSON/SKOV

2315Z CTC values down to around -23C/15 min on convective towers going up over Guadalupe county.  In Short Term Forecast we are saying expect storm growth to increase over east central zones next couple of hours.  Radar now showing increase in midlevel echoes and Severe TSTM Warning has been issued at 2338Z.

Garmon/Dutter

We blogged earlier about flooding likely in the storm on the Reeves/Pecos county line. The KMAF Storm Total Precip shows 4 to 5.5 inches of rain. This seems high for this area. You’d need 2.5 in/hr rain rates to get this, pretty hard with today’s precipitable water, even with high cape and Sfc dewpoints approaching 60F.

We looked at experimental Q2 from NSSL. Greg Stumpf pointed us to the SHSR VPR CORR. He can explain it better, but I believe it uses satellite data to improve radar estimates, especially when few radars are available. The 2300 UTC experimental Q2 with the correction is below.

The “vanilla” radar-only Q2 looks like this at 2300 UTC.

The Q2 is less than the STP, which is probably more accurate. The corrected Q2 looks a little higher than radar only Q2, but still more accurate than the 88D STP.

SNELSON/SKOV

The 22z run of the OUN WRF shows less potential for the Lubbock area but still shows development in the southwestern South Plains around 00z. We will continue to monitor but have shifted to the Amarillo area as convection enters the area from Colorado. The OUN WRF has been consistently showing the potential for growth of  complex through the evening.

Looking at 3DVAR data shows the stronger portion of storm remaining in extreme southeast Colorado at 2315z.

Here is what the Amarillo radar looks like at 2323z…

Tim/Ty

Based on latest satellite imagery and convective growth going on just east of the mountains east of ABQ…not ready to give up on OUNWRF depiction of storms increasing over eastern zones next 3 hours.   Surface temps in the middle 80s around KCVS have held back convective initiation over our east central and parts of our southeastern forecast area so far.

This just in to CNN…new warning on cell we were talking about over southern Chaves county!  Looks like the CTC was a good indicator in this case maybe.

Garmon/Dutter