EWP Blog

With scattered thunderstorms and limited severe threat in the ABQ area, we have been moved to SJT to hopefully capture convection moving northeast into the area from the dry line and leftover outflow from last nights convection.

Taking a look back at the visible satellite and convective initiation product, it highlighted the development of convection to the southwest of KBPG very well at 2000Z, with an area of 91% prob of development (and 67% to the south-southwest of that area).

Moving forward 30 minutes, you can see that area developed experienced development in several locations along that line.

-SRF

I didn’t get a chance to look at the NUCAPS soundings on Day 1 but as soon as the pass occurred today we looked at a sounding that was about 60 miles east of the storm of interest that we have been following in the northern portion of the MAF CWA.  The NUCAPS availability point was located in a brief area of clearing within the cumulus field but we were a little uncertain whether or not clouds interfered or not.

However, the data did look reasonable as the temp was close to surrounding obs, though the dewpoint appeared to be low compared to surrounding observations.  The SBCAPE in the NUCAPS sounding was about 245 J/kg which was significantly lower than the GOES-R LAP CAPE observation which was around 1000 J/kg.

We modified the sounding to increase the dewpoint to 59 degrees to be better in line and this resulted in SBCAPE of just under 1000 J/kg and lined up well with the GOES-R CAPE.

Jack Bauer

An area of convection (70% probability in GOES CI) continued to develop around 1900 UTC.  Between 1922 and 1928 UTC, the Prob Severe increased from 18% to 63%, and by 1935 was up to 86%.  The lightning jump increased to 2 sigma during this time.  The 1 minutes lightning density increased over a 2 minute time span from 1 to about 4 flashes/gridbox.   By 1945, the lightning density was up to 9 flashes/gridbox.  All of this evidence points to convection which is increasing in intensity.

Evidence from the NUCAPS sounding as well as the GOES LAP CAPE suggest the storm is in an environment with around 1000 J/kg of CAPE.  By 20:06, the storm is a well-organized supercell with a hook echo and well defined rotational velocity.

The combination of lightning data, Severe Prob, NUCAPS and GOES LAPE CAPE were good indicators of strengthening storm worth watching.  The storm produces a tornado.

Since I didn’t have time to test out the Lightning Cell Tracking and Time Series data yesterday, it was nice to have an opportunity to use it today. Overall, I think the lightning time series data can be really useful, especially the multiple color version.

One thing that was pointed out to me by one of the trainers was to keep an eye on the cell area (blue dashed line above), as significant drops/rises can indicate cell splits/mergers.  That was definitely the case with the image in the upper left of the four panel above, as the cell tracking was splitting/merging the lightning areas. That can be seen in the two images below, where the the first image shows the combined lightning cell with 39 flashes (2005Z lightning cell). Then the next minute (2006Z lightning cell), the detection split it into several different cells and lowered the total flash rates.

Knowing that information can help eliminate false interpretations of lightning jumps on the time series. -SRF

Pass came across with NUCAPS available at 20z. Looked at 19z data from a point close to AMA which launched an 18z sounding. First image is NUCAPS, Second image is the 18z AMA soundings. Differences notices were cooler temperatures above 300mb on the NUCAPS sounding. There was a small but more distinct cap near 800 mb on the AMA sounding. The freezing level and -20 level had dropped on both soundings compared to the 12z AMA sounding.

Lynford

The Probability Severe and ENI Thunderstorm Alerts seem to have differing opinions on a couple cells in the ABQ CWA.

At 1932Z, the cell to the north has a Dangerous Thunderstorm box, yet a prob severe of only 17%. Meanwhile, the southernmost cell has a prob severe of 78% but is only considered a “significant” thunderstorm.

At 1940Z, the prob severe of the south cell went up to 82% with no DTA, and the cell the the north went up to 43%. It’s interesting to note these cells are approaching the east/west boundary of the ENI Thunderstorm Alerts. No alerts showed up for the “east” algorithm either.

The storms are still pulsing down just as quickly as they develop. They really only look impressive for 1-2 volume scans. No hail or wind reports yet, just the funnel cloud near Roswell earlier.

-V. Darkbloom

Looking just beyond our LBB CWA to the south I noted a CI change from at 1845 UTC which showed 10% probability of convective initiation to a 70% probability at 1900 UTC.

However, when looking back at the radar loop starting at 1845 UTC which matches the first satellite image and continuing past 1900 UTC, we can see the development of an isolated convective cell.

At 1900 UTC a 39 dbz core was noted, so in this case the temporal resolution of the CI product (15 minutes) effectively resulted in a miss as the 35+ dbz was already present at the time the 70% probability was given.  This does not diminish the situational awareness value of the product.

Jack Bauer

Still monitoring storms across the ABQ area, but thus far they have been pulsing up and down with little maintenance. Here is a broad look at the area with ProbSevere overlayed on the radar.

The strongest storm is over the far southeastern part of the CWA, with a ProbSevere value around 77%. But looking at radar data, within the hail growth zone, seeing limited indications of severe hail. That is matched by the MRMS MESH output of right around 1″. Have not issued a warning for that storm at this point. -SRF

Today we are set up as WFO LBB in north central TX.  Water vapor imagery (upper left in image below) shows large upper low centered over the four corners region with broad cyclonic flow across NM/TX with plenty of dry air moving into the forecast area.  Visible imagery shows some general clearing across the area as thicker clouds moved out of the area from this morning.  Expect convection to develop later this afternoon as atmosphere destabilizes across the region with hail and damaging winds as the main threat. An initial look at the CI product (lower left in image below) is showing mainly low probabilities of initiation across the LBB CWA but there have been some higher probabilities to the west over NM closer to the core of the upper low where lapse rates are steeper and associated with the colder air aloft.

Looking at the GOES-R LAP precipitable water data the significant dry air is located in the 700-300mb level (lower left in the below image) which matches up well with RAP analysis soundings.    Not much on the radar this point to look at but will be monitor for developing convection.

Jack Bauer

Currently in the process of setting up in ABQ CWA for the afternoon and will provide a little bit of an overview.  Water Vapor imagery is showing a disutrbance shifting east across eastern New Mexico, as seen in the image below.

Already seeing convection over the area, both coming off the mountains and associated with the upper disturbance and also over the far eastern part of the cwa along the surface trough stretching south-southeast from the low in southeast Colorado.  While the convection coming off the higher terrain was already mature, the convective initiation product did pick up on the development of newer convection farther to the south and east of KROW.

As the storms continue to the east and into the higher instability shown on the GOES Sounder LAP CAPE, would expect the intensity of the storms to increase.

Finally, here is a look at the radar from 1842Z showing both of the areas of convection. Before developing this post, was planning on issuing a warning on a cell to the southwest of Mesa, NM, but technical issues with the Text Workstation inhibited the issuance. In the decision process, used the ProbSevere data to add confidence (increasing from 5% to 77% in about 15min) to the higher cores seen on the radar data.

SRF