Some significant differences in probabilities for v2 vs v3. Noted on this storm in northern New Mexico. Not quite sure the reasoning for this large discrepancy.
Storm ID: 346478 in Northern New Mexico June 9, 2022.
Notable Differences in ProbSevere in the time series.
Storms going up right along forecasted boundary from PHS CAPE
Storms developing in Prowers County in southeastern Colorado.
– David Spritz
The ProbSevere v3 drew attention to a cell near Bloomington, IN on the afternoon of June 8th. Specifically it was drawing attention to the wind threat with a high ProbWind percentage reaching 50% to 60%. However, radar interrogation was only initially yielding velocity of 30-40kts on the inbound side of the cell, sub-severe but certainly SPS worthy. There were a few scans yielding up to 45kts as well. So initially there was a little wondering why there was higher ProbWind percentages. Quick realization of the storm track being perpendicular to the radar beam could explain the lower velocity signatures here. Knowing this, ProbSevere and its ProbWind portion was drawing attention to a scenario that otherwise may have been missed if only looking at velocity data and not realizing the storm track relative to the radar beam.
ProbSevere v3 of “Bloomington Cell”
STP went up at 20Z coincident with new SPC mesoanalysis.
ProbSevere v3 readouts of “Bloomington Cell” at 1940Z
KIND Velocity signature of the “Bloomington Cell” @ 1941Z
The PHS SigTOR parameter also further supported the tornado risk during the 2000Z hour. The image below shows the PHS SigTOR parameter at 2000Z with ProbTOR percentages overlaid on top. The cell which produced the likely tornado east of Shelbyville, IN is sampled in the image with the ProbTOR only at 9%.
PHS SigTOR parameter pegging the area that produced a TOR. The cell highlighted with ProbTor readout produced the Tornado Warning referenced earlier.
From roughly 2130Z to 2200Z, a supercell passing west to east through west-central OH showed a persistent meso signature as seen from the KILN radar in Wilmington, OH. This signature eventually depicted gate-to-gate shear and tornado warnings were issued for this cell. The same ongoing Tornado Watch from the prior example also covered this same region. Image three also shows the PHS SigTOR Parameter showing higher tornado potential in the region, although not directly overlaid with where the Tipp City cell was. However, the ProbTor parameter of ProbSevere v3 did not show a corresponding jump in tornado potential. Unlike the prior example which showed the ProbSevere v3 grabbing a second much weaker cell with the tornado producing cell, this was a discrete cell with no merger occurring.
Highlighted in the Tornado Warning issued by the Wilmington, OH office, was a tornado debris signature. The KDAY metar located just south of Tipp City also included “tornado” in the remarks signature, shown in image four.
KILN SRM and V showing tornado signature near Tipp City.
Time series of ProbSevere with persistently low ProbTor for tornado warned storm west of Tipp City.
PHS SigTOR Parameter highlighting higher tornado potential in the region with overlaid ProbSevere – ProbTor percentage for tornado warned cell by Tipp City.
The KDAY metar showed “tornado” in the remarks section for the cell passing through Tipp City.
– Trip
At 2144Z the Prob Severe V2 tornado jumped to 21% while V3 only went to 6%.
PHS CAPE values increase from north to south over Fort Stockton. This correlated well with RAP mesoanalyzed SB CAPE on SPC webpage. Storms actively going up along this gradient as an outflow boundary pushed south during the early afternoon from overnight convection over Oklahoma.
PHS CAPE 18Z 1 hour forecast for 19Z
PHS CAPE 18Z 2 hour forecast for 20Z.
Storms developing over Fort Stockton via Day Cloud Phase Distinction on GOES 17 Mesosector
We showed above that the north side of the outflow would contain more instability – which is directly related to the moisture from the morning MCS outflow. The Gridded NUCAPS provides additional insight using the 850mb moisture fields from both AQUA and NOAA20 respectively – validating our hypothesis.
We double checked since there was a dust advisory/dust in the forecast and yes – Dust
Don’t warn if pop = 0
Convection was skirting the northeast portion of the CWA so we’ll use the recent pass of NOAA-20 to view the potential for convection redevelopment to the west and affecting the forecast in our CWA. Here are the Modified NUCAPS soundings:
The top image is for the sounding in Jones county, below is Scurry – which shows a capping inversion still in place.
Weak winds aloft and throughout the atmosphere have contributed to very little in the way of storm motion. Hence, locally heavy rainfall may begin to evolve, even over an area that has received very little rainfall in the last 6 months.
Optical Flow Winds in the 200-100 mb level.
Day Cloud Phase valid 2041Z.
Day Cloud Phase valid 2141Z.
PHS depicts this plume of moisture and associated instability will back into New Mexico this evening. Could it play a part in tomorrow’s severe weather risk?
Here is what happened at El Paso when the front backed into the area – Dewpoint jumped from 30F to 50F
– David Spritz
– Mr. Bean
NUCAPS Sounding (IND 06/08/2022 2019 UTC)
Lowering maxFED values effectively highlights the area of strongest thunderstorm activity as seen in this example. This makes the strongest two thunderstorms (circled) more distinguishable from other thunderstorms, especially on the northern circled thunderstorm. It should be noted that this may be even more effective during the initiation to nearing maturity stages. Once a storm reaches full maturity, FED signal may be much higher.
– 2%hatched
NUCAPS Sounding (1832 UTC)
NUCAPS Modified Sounding (1832 UTC)
NUCAPS and NUCAPS Modified soundings displayed were along a warm frontal passage lifting south to north across southern Indiana. The modified NUCAPS sounding provided a more realistic depiction of the environment with higher levels of instability (CAPE and DCAPE). Furthermore, the LCL values represented in the modified sounding were lower; depicting an environment more favorable for tornadoes along the warm front.
– 2%hatched
Being on the western edge in the North Platte County Warning area we did a comparison versus GOES 16 and 17 with the GLM Flash Extent Density. At first there wasn’t much of a difference, but when storms started to ramp up more and we had a decent eastern and western storm there was a difference.
As you can see our eastern storm shows up better on GOES 16 and not as good on GOES 17. Meanwhile the western storm there is a much greater difference in the Flash Extent Density (and Total Optical Energy) on GOES 17. This matches with what was stated at the initial discussion this morning that GOES 17 may work better with western storms.
-Noctilucent
Nowcasting Supercell storm entering CWA: The loop of instability and SigTor highlight the southeast/south central CWA east of Colorado Spring, ahead of an already ongoing storm. North of this storm an environment of favorable instability exists up to about the latitude of Denver, with a significant drop off to the north.
When it comes to high and northern plains – parallax becomes an issue. In this case lighting was occurring just on the other side of the border with the CWA, so here are the two LightningCasts (with/without parallax correction) for comparison:
ProbSevere v3 increases correlating to entering a favorable environment
PHI localized CAPE corridor
New area of MFA suggesting spitting storm with new updraft core of the established cell. (1950 UTC)
Storm cell split denoted by MFA with two distinct areas of MFA in upper right panel. (2000 UTC)
Focused on the cell east of Denver – this cell and subsequent others that developed are in the favorable area of instability. Just to the north of Boulder we spotted a few cells that attempted to develop, however in the lower instability environment movement off the higher terrain resulted in these cells falling apart. Through the rest of the afternoon this area remained convection free.
Sig Tor blip. A SRVE like feature was observed but at this time convergence associated with this feature wasn’t favorably located under the updraft.
Cell developing east of Denver, noted by the MFA in the upper right panel. (2020 UTC)
Cell rapidly develops in an area of localized higher instability denoted by the PHS values discussed earlier on.(2034 UTC)
The LightningCast has identified the left turning nature of the storm(s) east of Denver
An interesting note was comparing the differences between GOES East (left panel) and GOES West (right panel). These subtle differences can be effective in analyzing the strengthening of a thunderstorm.
In the middle of METWATCH – NUCAPS became available (about 1 hour latency). The sounding below is a modified NUCAPS profile, depicting the environment in which our storms developed. Storm mode was supercellular with frequent spitting of cells.
-Mr. Bean
-2%hatched
