Both teams continue to follow the same storms mentioned in the previous post. A glitch has prevented auto-updates in AWIPS D2D, but WDSSII is operating well. Team 2 notes their lead storm is taking on HP character as it approaches the north side of Tucumcari. They are toning the tornado probability down while maintaining a high probability of severe hail. They will also initiate a damaging wind threat area.

Kevin of Team 2 examining side-by-side supercells:

Team 1 has threats for hail on both the Chaves and Alamagordo storms. They have a low probability tornado threat area for the Chaves storm, which has just begun to interact with the aforementioned boundary.

Brad with Team 1 monitors the Alamagordo storm from his workstation and using the SADS:

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

Both teams appear comfortable with handling multiple threats, even on multiple storms. Team 1 is warning for hail with the storm east of Chaves. They are curious to see how this storm evolves upon interacting with a NNW-SSE oriented boundary located in the path of the storm. They also issued a high confidence hail warning for a storm southeast of Alamagordo…which has a 3-body scatter spike, and for which MESH indicates 3 inch hail.

Team 2 has been following a long-lived supercell which has occasionally produced a TVS, and at one time a fairly strong TVS…tracking just north of I-40 toward Tucumcari. They are maintaining high probabilities for hail and tornado with this cell…and have just added a low probability for tornado with a second supercell following in the path of the first. These cells are moving along an east-west oriented boundary of unknown origin…which may have bee produced by differential heating.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

PROB-WARN Ramping Up

Forecasters will head back to the Hazardous Weather Testbed to practice drawing probabilistic warnings…then an intensive operations period is planned beginning sometime after 2200 UTC…most likely in the area just east and southeast of Albuquerque, NM. Northeast parts of the state may be too stable to support a long-lived storm.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

Eastern New Mexico Heating Up

The SPC has outlined a mesoscale discussion for eastern New Mexico, where a weather watch may be needed soon. Satellite and surface observations suggest the original target of northeast NM has been slow to warm up beneath widespread stratocumulus clouds north of the frontal boundary. Greater destabilization has taken place along the I-25 corridor and into east-central/southeast NM. This zone of greater instability should develop northward this afternoon. Thunderstorms are initiating in a widely scattered fashion between Albuquerque, Pecos, and Clovis. One cell near ABQ briefly exhibited supercell character with a small appendage and sharp reflectivity gradient.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

Archive Cases Ending…Prob Warn Training to Begin

Our teams are filling out PAR and CASA evaluations following their archived events.

Kevin/Eric discussed how to best display CASA data. They would like to be able to easily choose one radar and tilt up to higher elevation. They like the utility of CASA at low levels for wind/tornado threat without much thought to hail threat.

Yesterday…they were hanging on every 1-minute update with PAR, looking intently for changes in storm character. They did not experience the same type of anticipation with CASA today. This could be related to the case selection. Some positives they point out are the fine spatial resolution and near ground sampling.

With both PAR and CASA, Kevin sees need for substantial training to avoid dramatic increase in false alarm rate. These small scale signatures and short-lived shear couplets or RFDs have always been out there. Now that we can see them, it doesn’t necessarily mean we should be warning for each of them.

Brad/Eric are discussing when additional information becomes too much. “Rarely would a meteorologist decline more information, but in some cases it just becomes more on the floor (or tossed aside).”

All forecasters are moving to a seminar room for training on Probabilistic Warnings from 2045-2130 UTC.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

Storms in western Oklahoma have either weakened or moved southward to very long range from central Oklahoma radars. Today’s severe potential is largely driven by the diurnal cycle, and there is little hope of additional activity; the MCS outflow from this morning simply proved too deep and widespread across central Oklahoma. The event did provide Eric and Kevin a chance to become familiar with PAR data, and they will continue that theme by working an archived event this evening.

Meanwhile, Brad and Mark are viewing archived CASA data to increase their comfort level with the look and feel of that data. Between 2330 UTC and 0130 UTC they plan to run through another event in real-time playback to evaluate the utility of CASA data in making warning decisions.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)

PAR Temporal Resolution Discussion…

Eric & Kevin are working the Altus storm… and their first look at PAR and 88D side by side has sparked discussion of the differences in resolution and sampling techniques. Kevin would like to see enhanced azimuthal resolution (lower beam width) for PAR in the future. Kevin remarks that the 1-minute update has made it easier to pick up on new cell development along the storm’s rear outflow flank. The forecasters earlier observed a supercell split on the Elk City storm…and felt the rapid updates were beneficial to seeing this.

Eric has another interesting perspective. He thinks the 1-minute resolution might be “annoying” early in an event when you don’t yet have a particular severe weather threat or focus. It may be overwhelming to process so much data. Maybe we should apply the forecast funnel to this… and be able to choose when to switch from 5 or 10 minute resolution down to the 1-minute resolution as needed.

Patrick Burke (EWP Weekly Coordinator, 27-30 May)