GLM spikes for northern NE storms

Tracking northern NE storms, we could see the GLM spikes on rapidly strengthening thunderstorms across Sheridan and Cherry counties in north-central part of the state. These storms are exhibiting strong hail and wind signals and golf ball sized hail was reported by the public. Interestingly enough, while the initial spikes were impressive, the storms further south and west (south of the warm front) seem to have a higher GLM total energy and density overall and for a longer duration.

- Jack Swigert

Noticeable increase in GLM lightning detection

Noticed a marked increase in Flash Density, Total Energy, and Average Flash Area as the storm strengthened over Garden County Nebraska (same storm from earlier blog posts where warning was issued). Included an animation of the GLM data along with ENTLN and NLDN to calibrate my thinking a bit.

On the average flash area notice the large flash stretching across Cheyenne and Deuel counties in Nebraska.

More to come...

Supercell

Severe Storm with All Sky CAPE Prob Severe

Interrogated a storm entering the gradient in instability shown by the All Sky CAPE products and also increasing Prob Hail and Wind Products (cell with SVR box on it). The cell is moving into Garden County Nebraska:

More to come...

Supercell

Severe storm exhibiting almost no ltg

Severe storm in north Nebraska (Z shown)

GLM 4 panel (FED,Area,Total energy) showing almost no lightning activity

ProbSevereWindTor with severe storm

Looked at Prob Severe Tor/Wind/Hail with MRMS reflectivity. The Hail probabilities actually increased to 90% prior to warning issuance. MESH values were around 1.56 inches. Prob Wind was a lower (78%) value. Did see where there was a TBSS in the dual pol and reflectivity products indicative of hail. Issued severe thunderstorm warning shortly after the probs showed this. Did notice that Prob Tor was around 1% but monitoring the velocities as the cell is located near the warm front and wind shear is sufficient to support it.

More to come...

Supercell

NUCAPS vs LAPS Discrepancies

ALL SKY LAPS showing around 1600 CAPE (not sure what CAPE is being computed? ML,MU,SB?)

One green point selected from NUCAPS showing 3200 SB and 2200 ML CAPE, much higher than ALL SKY, but SFC DP and Temp match METAR obs showin in figure 1

CAPE much more in line with what SKY LAPS is showing, but Temp (DP) seem to be higher (lower)

North Platte 20Z Special Launch vs 20Z NUCAPS

Just doing a quick comparison between 20Z NUCAPS modified sounding near North Platte (green dot southeast) to 20Z Special RAOB launch from North Platte.

NUCAPS 20Z                                              KLBF 20Z

Overall, it picked up the genaral temp and dewpoint profiles fairly well, but there were a few noticeable differences. NUCAPS failed to pick up on the elevated mix layer that the KLBF sounding did. NUCAPS therefore had a weaker capping inversion and a lower freezing level. KLBF had a drier mid-level.

- Jack Swigert

No To Low CI and Storm Initiation

Noticed that a cell (circled on image) over northeastern Wyoming did not have any severe CI, low CI (17%) before it initiated. Not sure what may be happening with the algorithm. There was no cirrus canopy around the cell other than other convective initiation (south) and clear air (north).  Included the beginning image:

Here is the last image I took of the storm:

You can see that it has a strong updraft (via IR Satellite). I do not have severe CI displayed but it had no values in around that particular cell. With it moving towards a gradient in instability, could see it strengthen further soon.

More to come...

Supercell

Severe CI Product hinting at initiation in northern Nebraska throughout the early afternoon

northern Nebraska convective initiation after severe CI hinted in that region with high percentages (although jumpy) all throughout the early afternoon.

All Sky Products Environment Analysis

Utilized the All Sky CAPE and Precipitable H2O products compared to the HRRR data. Could definitely see the All Sky CAPE is showing a good gradient close to where storms are already developing and have gone severe near CYS radar. Note: The severity of the storms is not shown in the radar. It was included in this image mainly as a frame of reference where cells started to develop. Later volume scans showed much more organized updrafts.

Would expect these cells to continue to strengthen or maintain their strength as they head eastward across the gradient.

More to come...

Supercell