Outflow Captured by Radar and Octane Speed Sandwich in West Florida
An outflow boundary tracking west towards a DSS Event in Tampa shown via radar. The outflow could be seen up to 20000 to 2500 feet MSL on radar. 
Octane Speed Sandwich also captured the outflow boundary approaching the DSS Event. 
-Dwight Schrute
The 19Z NUCAPS sounding pass went over Florida as convection was ongoing across much of the state. The 850mb to 700mb lapse rate product picked up on some of the convective overturning in southern Florida where lapse rates were far less steep than other portions of the state (indicative of cooler low levels), as well as where low level lapse rates were a bit lower over the western coast. This lines up well with where the RAP was showing lower surface to 3 km lapse rates. Though these two levels are not completely analogous , they represent similar processes post-convection. However, the NUCAPS pass is also picking up on lower 850-700mb lapse rates over Georgia and South Carolina which doesn’t match with the lower lapse rate product from the RAP, but these areas were also not experiencing convection so the reason for this could be due to other factors.
-Joaq
After a few days at the HWT I have decided to make a four panel of my own with the new products which has been working great! On the top left we have Octane Speed with Octane direction on the top left. We have Vis with lightningcast and GLM 1 min lightning on bottom left. On bottom right I have MRMS data and ProbSevere V3. I was very happy with this display for situational awareness.
Also in the image below we can easily spot a stronger storm in a cluster of cells in Park County looking at directional and speed shear with Octane. Then we can quickly look down at ProbSevere and see its on the one storm being highlighted. That tells me this is the storm that I need to watch over the next 10-15 minutes for development.
-Thunderstruck
General Risk for Thunderstorms in Florida this Afternoon and Evening
The Tampa CWA is in a general risk for thunderstorms this afternoon and evening per the SPC.
The main potential impacts are frequent lightning, heavy rainfall, and gusty winds thanks to decent amounts of SBCAPE. Localized flooding also remains possible, especially in urban areas, due to slow storm motion as PHS shows no 0-6 km Bulk Shear over Florida. This matches well with the latest SPC Mesoanalysis which also shows no 0-6 km Bulk Shear shear over the region.
NUCAPS showing SBCAPE values at 21Z. Values are highest across the central and southern portions of the Tampa CWA. Areas in green had values around 1600-1700 J/kg. Areas in teal show values ranging from 800-1400 J/kg. Areas in purple range from 200-300 J/kg. 
PHS shows a similar trend to NUCAPs with higher areas of SBCAPE across the central and southern CWA with lower values across the northern half of the CWA. However, the color scale on the online version of PHS is difficult to interpret as the gradient ramps up from light red to dark red. So, you cannot really pinpoint specific values of SBCAPE. However, you are able to see areas of lower SBCAPE and areas of higher SBCAPE at a glance. 
ProbSevere version 3 increases our confidence that storms will remain generally sub-severe as ProbSevere values are below 10% across the Tampa CWA as of 1930Z.
The Octane Speed Sandwich product further confirms that storms are remaining below severe limits as the strongest storms are noted over southeastern Florida this afternoon as of 1930Z. Not only do these products help us pinpoint areas of potential severe weather, but they also help us pinpoint areas of sub-severe weather. 
GLM shows lightning activity increasing across the Tampa CWA early this afternoon, and activity is expected to gradually increase in coverage as more thunderstorms develop through the late afternoon and early evening hours. 
Lightning Cast around 1930Z shows lightning probabilities increasing across the Tampa CWA over the next hour. Pink contours represent a 75% chance of lightning in the next hour. Green represents a 50% chance, teal a 20% chance, and dark blue a10% chance of lightning in the next hour. 
GLM showing lightning activity increasing across Florida from 1930Z through 2016Z across the Tampa CWA. Areas showing more oranges and yellows have shorter flashes and more lightning density. These areas help us know where stronger updrafts are located. The strongest updrafts at the time of this loop remain outside of the Tampa CWA. 
-Dwight Schrute
GLM FED/MFA RGB here shows the rapid thunderstorm life cycles in the weakly sheared but highly unstable Florida atmosphere, as reds to yellows (intensifying convection with lots of short cloud flashes) give way to blues and purples (weakening convection with fewer but longer flashes). The range rings circle today’s DSS event, which also highlights the difficult nature of producing storm by storm headlines or products for public safety as the life span of these thunderstorms are brief. The messaging for today highlights the consistently sporadic lightning threat for anyone on the coast or at the DSS site while storms build and collapse over a matter of minutes. 
-Joaq
GLM RGB showed the progression of a developing storm near the TBW DSS site this afternoon. Not only was lightning a threat communicated to the DSS site, but KTBW radar depicted a downburst signature as shown below, which prompted us to issue an SPS for wind to around 40 mph, frequent lightning, and heavy rain. 
track a developing storm near the Florida State Fair
-Joaq
A severe thunderstorm warning decision in eastern New Mexico was a challenge today as it was within a KABX beam blockage and the eastern NM radar, KFDX, was down. The signs of the intensifying storm were found on satellite, GLM, and then slowly ProbSevere as the radar reflectivity heights from KAMA (the nearest valid radar) were very disorganized and slow to respond compared to the trends depicted by satellite and GLM trends. An above anvil cirrus plume, IR thermal couplet, consistent GLM FED/MFE signature, and cloud top divergence depicted by the Octane Speed/Direction product showed signs of strong convection developing. While reflectivity below showed just a minimal 50 dbz core and no 60 dbz core. As ProbSevere V3 gradually increased to around 35%, the ProbSevere Satellite Growth/Intense Convection Prob. quickly increased. The satellite growth/Intense Convection is not weighted as high in V2 and because of that ProbSevere was much lower at the same time. While the radar reflectivity core was still missing, we decided to issue a warning for the storm given the other satellite based signatures. ProbSevere V3 began to show strong chances for severe weather approximately 13 minutes after the warning was issued, and a strong 60 dbz core developed on the KAMA radar shortly after with MESH getting as high as 3.5 inches.
GOES-16 Octane Direction. 
GOES-16 Octane Speed.
GOES-16 GLM RGB
KABX 0.5 degree reflectivity.
KAMA 0.5 degree reflectivity.
KPUX 0.5 degree reflectivity.

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ProbSevere probability charts.
MRMS output showing radar data approximately 20 minutes after warning issuance.
-Thunderstruck
– Joaq
PHS Model Comparisons and Thoughts
Above: Top is HRRR SHIP parameter, bottom is PHS SHIP parameter.
Looking at some of the convective parameters and indices around the CWA I was working with today (PUB), one thing that really stood out to me was how “splotchy” many of the parameters were when compared with the HRRR model. It’s very hard to believe that the model, especially at a 3 km resolution, is able to obtain that level of accuracy with regards to these parameters, or at the very least having gradients this sharp in many of these parameters doesn’t make much sense. Wondering if some of it is being driven by the extreme CAPE gradients that do show up later on, which are certainly going to be drivers in many of the severe indices.
Another thing I noticed is what looks to be a wave-like numerical instability within the first hour of the model – this could be having some big impacts on the model forecast, as you can see these reflected in the base fields (T, u, v, etc) and then having impacts on many of the other derived parameters that last through the forecast period, as shown in the image below:
CAPE also seems to initialize really high, then “jump” down to a lower value at the first hour. This is quite a large “adjustment” from the initial conditions that the model seems to start with. Shown below are hour 0 of the 14Z run and hour 1 of the 14Z run from Wednesday 5/24.
You can also see the numerical instability within this field that is in place across a large portion of the domain.
OCTANE
Octane was able to capture an interesting view of the Above Anvil Cirrus Plume on a very powerful storm along the New Mexico/Colorado border during the afternoon hours. The cirrus is a bit slower than the surrounding clouds within the sheared environment, providing that “V” type shape that we’ve come to associate with some of the strongest updrafts:
Another good example of using Octane for surveillance of storms – the direction product really highlighted another storm that quickly grew on the flank of another severe warned storm. Big value especially in areas where radar coverage might be limited by mountains, such as in the CWA I was working in today (PUB):
LightningCast
Used the LightningCast product extensively for DSS purposes today. We had a pretend outdoor event located in Pueblo, Colorado. A very strong thunderstorm (MESH estimated nearly 3″ or larger hail at one point) which passed within a few miles to the south and east of the city. I used the LightningCast probabilities in AWIPS overlaid with satellite data to provide multiple updates to Emergency Management, using it to confidently state that probabilities of lightning were increasing as storms approached from the south. Lead time for action would have been within the 45 min to 1 hour range. Was able to confidently say they would see lightning within the 10 mile range a good 15-30 minutes before the first strike occurred within the range per the ENTLN network data. Below is the LightningCast time series as output on the webpage for the KPUB airport, which is very close to where the DSS event was taking place:
There is definitely some very actionable lead time here. As a forecaster, having this type of data available to me outside of AWIPS is a game changer. I know it may be challenging, but being able to click on a point like this and get this type of information would be huge for briefings and emails with decision makers. Right now we are limited to airports. Even a relatively coarse mesh that would allow me to pick a close point would be extremely useful if these images can’t be generated on the fly. Other possible ideas include only generating points within a certain LightningCast threshold (say 10%), or generating them on the fly based on a click query. That all said, even in its current form I will be using it going forward, and making a point to share it with my office and WCM for DSS.
I also made a social media type graphic using the LightningCast product for hikers, given the large number of mountains within the CWA. Perhaps would have been a bit more meaningful to have sent this as storms were beginning to form, but they were already cooking once we got spun up and started. Highest probabilities were hugging the mountains where storms were forming. If I were formally posting to social media, I may have added some lightning safety graphics or something to that effect as part of the post (twitter thread, multiple images in Facebook post).
GLM RGB
This product does a great job in my opinion combining information from the FED and MFA. I found it useful for detecting lightning jumps within storms while still maintaining information about the overall coverage of lighting. Would happily use this as my primary GLM viewing option in AWIPS.
-Carl Coriolis
Today we focused on the Pueblo, Colorado CWA for afternoon High Plains convection. Scattered convection developed across the CWA leading to large hail and damaging winds. The first Severe Thunderstorm formed on our CWA border with Albuquerque and drifting south into their CWA. A second Severe storm developed and tracked north towards our DSS Event in Pueblo, bringing the potential for large damaging hail and strong winds.
15Z PHS MUCAPE valid at 18Z showed around 2000 to 2500 J/kg for green areas while areas in blue had roughly 1000 to 2000 J/kg.
SPC MUCAPE Mesoanalysis valid at 18Z shows similar trends to the 15Z PHS MUCAPE values.
16Z PHS valid at 21Z showed a slight upward trend of MUCAPE in the eastern half of the CWA. 
21Z SPC Mesoanalysis showed increasing values of MUCAPE developing just south-southeast of the CWA, similar to the 16Z run of the PHS shown above. 
15Z PHS STP valid at 18Z showing little overall threat for tornado concerns through early afternoon, for the most part values were less than 0.25. 
SPC Mesoanalysis page showing 18Z STP values similar to the 15Z PHS forecast. 
The image below shows the Octane Speed product on the left and the Octane Direction product on the right, focusing on a cluster of activity near the Jefferson/Douglas County line in Colorado. Picked this screen capture as it showed a wide range in values, mainly for the Direction product. The Octane Speed product shows some speed shear present with the lighter speeds (darker blue, ~5 kts) transitioning to brighter green/a bit of yellow (~30 kts). The magnitude of directional shear was higher, showing direction of motion/divergence ranging from ~170 degrees (core of red area) to ~295 degrees (core of green area).
Below is a animated graphic showing the transition in both products. 
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Chose to grab this Octane Direction product screen capture as it shows an elongated area of storm top divergence through central Colorado. The red/magenta colors show direction generally from the 170-190 degree range, while the green/yellow colors show values from the 275-285 degree range. The black areas are spots of data dropout, which can occur when the speed shear product drops below 5kts.
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First Severe Thunderstorm Warning issued for this area today came right after 20Z, based on ProbSevere values/time series as well as the Octane Speed Sandwich product. 
Probabilities ramped up quickly for both ProbSevere and ProbHail on this storm at the edge of the PUB/ABQ CWA boundary. 
Octane around “peak” of the storm.
Low Level SRM and ProbSvr (0.5 deg slice is about 10.8k ft AGL)
Mesh showing 3 inch hail on the border of the Pueblo CWA. 
ProbSevere and ProbHail maxed out at roughly 90% while the storm remained severe. This storm eventually moved into ABQ’s CWA.
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2nd Severe Thunderstorm Warning – Huerfano County
ProbSevere values and time series for 2nd Severe Thunderstorm Warning of the day, readout is at its “peak”…around 2045Z.
Octane Speed/Direction at “Peak” of the storm, around 2045Z. Directional shear varied from ~205 degrees (reds) to ~285 degrees (greens). 
ProbSevere showing the weakening trend of the storm gave us confidence that the storm was in fact weakening. 
Octane speed/direction further confirming the weakening trend as colors become more diffuse in nature.
ProbSevere showing continued weakening trend. We decided not to issue another severe thunderstorm warning on this storm based on the trend.
Though this storm showed a weakening trend, it was a short-lived trend, as it still had ~2000 j/kg of MUCAPE and effective shear around 30kts to work with as it tracked farther north. 
The storm ended up re-intensifying, as shown by the ProbSevere output/time series below. We went ahead and issued another Severe Thunderstorm Warning for very large hail. 
An increase in both storm top speed/directional shear was also shown by the Octane product.
The level reflectivity images show an impressive core peaking in the 36-40k ft range, shown in the 12.5 deg. slice. 
MESH showing nearly 4 inch hail south of our DSS event in Pueblo. The event was notified about the potential for large damaging hail.
-Dwight Schrute/Bubbles
This image shows Day Cloud Phase Distinction, LightningCast, and 5 Minute CG Flash Lightning Plots for NLDN and ENTLN across Eastern MT. While LightningCast provides a lot of information, it’s easy for it to overwhelm forecasters in situations like what’s shown, especially if other colorful imagery is included. A suggestion is to give forecasters the option to load LightningCast in 10% increments from 10-90% (10, 20, 30, etc). Then, forecasters can turn the individual increments on or off depending on the situation (i.e. lots of severe weather can prompt the lower values to be turned off, or partners concerned with the initial start of lightning can prompt lower values to be turned on). Having the ability to change the color, line style, and line width for each increment would also be nice.
-Champion