SPG2026 – Page 2

Viewing Low-Level Features With MesoAnywhere

Posted in OCTANE Speed Sandwich, SPG2026 on May 12, 2026 by Kevin Thiel.

There wasn’t much convection today over the MFL CWA, so I spent a lot of time looking at MesoAnywhere to see how it performs compared to the Day Cloud Phase Distinction RGB from both CONUS scale and meso sector 1.

Some sort of boundary was evident on radar extending southwest from an area of showers west of the Miami radar.

Figure 1- Radar image from KAMX radar showing a boundary extending away from an area of showers.

I wanted to see if this boundary was noticeable on satellite, so I pulled up all of the available Day Cloud Phase RGB scales that we had, including from MesoAnywhere.

The boundary is noticeable, but what stood out to me more was the motion of the low-level clouds in the MesoAnywhere product compared to the others. It seems that the motion of the high cirrus clouds was affecting how the motion of the low cumulus was being depicted. Instead of moving to the north like in the other 3 panels, it shows a general west to east motion.

While this doesn’t matter so much in this case since we did have a meso sector available, this becomes a problem if we don’t. The CONUS imagery offers a much better picture of how the clouds are actually moving, but we lose out on the 1 minute imagery.

ei2018

SPG Blog Post Day 2 – Daytona RFD

Posted in OCTANE Speed Sandwich, SPG2026 on May 12, 2026 by Kevin Thiel.

Deep convection was prevalent during the afternoon of Tuesday May 12th, 2026. There were several interesting artifacts in the satellite imagery that were noted this day. There were also several different storm types observed such as single cell “pop up” storms, a linear area of storms as well as a few supercells which eventually transitioned into clusters of slow moving storms. Something I thought was particularly unique was the Rear-Flank Downdraft (RFD) on a supercell moving north to south near Daytona Beach while there was a clear west to east steering flow.

This storm initially developed north of the area near Clay County. As it moved off the coast, it strengthened quickly then had an anomalous southerly storm motion as everything else was generally moving east. As the storm pulsed up and down in strength, there were periods where the OCTANE Speed imagery caught the RFD pop out with the green coloring west of the main updraft. You can see that below on Figure 1.

While this is not something out of the ordinary, it was most visible on this satellite product because upper level cirrus blocked this process on other satellite imagery.

Figure 1: Rear-Flank Downdraft (RFD) captured on the Octane Speed imagery as a storm with anomalous south motion moves through the easterly flow.

SPG Blog Post Day 2

Posted in OCTANE Speed Sandwich, SPG2026, Synthetic GXI, SZA Imagery on May 12, 2026 by Kevin Thiel.

Today, forecasters were located over the MLB and TBW CWAs for a marginal risk over the FL peninsula. Stationary frontal boundary right over the peninsula, with some sea breeze boundaries right along the coastline. Today, I was simulating a forecaster at the MLB office.

Figure 1: SZA Comparison ECONUS Product

Around 18Z, I noticed the SZA product had better resolution for analyzing cloud top structure, and picking out some finer details.
- The SZA and RGB product became more similar later in the afternoon, which is expected. Resolution began to improve on SZA compared to RGB closer to sunset.

Figure 2: OCTANE CTC

The CTC product was great for identifying rapidly developing storms during this event. There was one impressive cell that developed by Kissimmee, and the CTC product highlighted these cloud tops very well.
- From a forecaster perspective, it helped me to pinpoint an area that needed further analysis, and my team and I decided quickly afterwards that a warning needed to be issued for this storm.
- The speed product was also helpful for visualizing storm motion. Rescaling the product back out to the CONUS scale helped put into perspective where faster moving storms were located.
Additionally for the OCTANE suite, I paired the MesoAnywhere, LightningCast spotlight, and MRMS data in a perspective. In this perspective, I had the “red” 0-10 minute values flashing, and semi-transparent, so you could see the data below the stoplight.
- Stoplight was very helpful in the DSS realm. I used it for a quick guide to respond to partners about event precautions.

Figure 3: WV/WVT/IRob/VISob Compare 4 panel

Something very interesting that was noticed on the WVT imagery, was sea breeze moisture moving in on the FL east coast. I toggled with the colormap a little bit, making the minimum be 0.2, and the maximum be 1. This makes it a little easier to watch the darker colors, representing the moisture, move in from the ocean. Very interesting feature to capture on the simulated satellite imagery!
- The 5.15 imagery did not seem to capture this as well, which makes sense as the sea breeze was probably a very shallow feature.

Kelvin-Helm

Overview: Week 2, Day 2

Posted in Daily Summaries, OCTANE Speed Sandwich, SPG2026, Synthetic GXI, SZA Imagery on May 12, 2026 by Kevin Thiel.

10 AM

Tuesday began with a group discussion and first impressions for the five experimental products. Topics included how forecasters applied LightningCast and the Lightning Stoplight, OCTANE Cloud-Top Cooling for monitoring updraft strength, and the value of SZA imagery near sunrise to observe low clouds and fog. I showed an example of the SZA Day Cloud Phase Distinction RGB on CIRA-SLIDER, with clouds and storms across Florida around sunrise. I asked the forecasters to identify what time the imagery became ‘usable’ for them, and compared it against the traditional imagery of the same scene. Here were the results:

Traditional imagery: 1131 Z, 1141 Z, 1151 Z, 1206 Z
SZA imagery: 1051 Z (x3), 1101 Z

I’m hoping to run a similar experiment with SZA imagery near sunset tomorrow. Here’s the imagery I showed today. When do you think each imagery becomes ‘usable’?

Traditional Day Cloud Phase Distinction RGB

SZA Day Cloud Phase Distinction RGB

We jumped into our forecast discussion, which asked the question ‘Can we avoid going back to Florida again?’ Unfortunately that answer was NO, so we localized to NWS Melbourne, FL and NWS Miami, FL.

1 PM

Shortly after ops started SPC issued an MD for the Florida peninsula.

Forecasters in the MFL office talked about providing DSS with LightningCast and Lightning Stoplight, and noticed in the OCTANE MesoAnywhere product how cirrus motions aloft cloud interfere with low cloud motions. MesoAnywhere is on the left, ABI MESO imagery is on the right.

Forecasters in the MLB office issued a handful of warnings, and we had a discussion about the OCTANE-CONUS Cloud-Top Cooling product. While the OCTANE MESO products showed more information, forecasters still found the OCTANE-CONUS products useful if a MESO wasn’t availalble in this case.

Late in the day we viewed the frontal boundary in KS where storms might initiate this evening through the Synthetic GXI products, namely the 5.15 µm and WVT products. We compared them with the ABI split window moisture field (10.3-12.2 bands) and the ALPW from JPSS. In talking with another developer, we got the idea to create a ‘sandwich’ product that meshes the WVT and ABI Split Window products.

-Kevin

SPG Blog Post Florida Convection 05-11-2026

Posted in OCTANE Speed Sandwich, SPG2026, Synthetic GXI on May 11, 2026 by Kevin Thiel.

Deep convection was hard to come by in Florida on May 11th, 2026 but a weakening storm did move over a land breeze boundary along the coast during the late afternoon and into the evening. The land breeze was visible on the GeoXO viewer and can be seen as a buildup of moisture along the coast which then dissipates around 2200z. Figure 1 shows this buildup of moisture very well.

Figure 1: Land breeze moisture build up along the East Coast of Florida.

As a weakening thunderstorm traversed over the boundary, it was reinvigorated and strengthened rapidly. This can be seen below on Figure 2. A thunderstorm moved over the boundary, seemingly absorbed the moisture at the boundary and developed deep convection over the ocean.

Figure 2: A thunderstorm moved over a land breeze boundary and restrengthened.

Batman

Florida Convection – May 11 2026

Posted in SPG2026, Synthetic GXI on May 11, 2026 by Kevin Thiel.

Today we examined several experimental satellite products, LightningCast V2, Synthetic GXI, and Solar Zenith Angle – Adjusted (SZA) Imagery, OCTANE, and Lightning Stoplight over north central Florida. It was a relatively quiet convective day across the CONUS, especially for mid May with the only area of significant convection over north central Florida.

While I was already very familiar with the LightningCast V2, the Stoplight and the SZA imagery, the product that sparked the most interest to me or was most excited about its future capabilities was the synthetic GXI imagery, which uses the 0.91 µm and the Water Vapor Transmittance (WVT) or the ratio of the 0.91 µm/0.86 µm channels. Once these two new channels become available on the Next Generation of GOES satellites, GeoXO, I believe these two new products will become extremely useful in determining moisture gradients or moisture pooling and it would be of greater utility than the current Split Window Difference (SWD) product available from the current GOES Advanced Baseline Imager (ABI). In particular, the WVT image below (top right panel) clearly showed a moisture gradient (darker colors representing higher TPW vs brighter color colors representing lower TPW) associated with a cold front sinking into the Gulf Coast states.

Figure 1 (above): Four Panel Display of GeoXO imagery showing the 5.5 µm and the WVT products at the top left and right respectively, and the “Clean” Window IR and VIS channels at the bottom left and right respectively.

Figure 2. WPC Surface Analysis valid 18 UTC Mon May 11 2026 showing cold front extending from the Carolinas southwestward to the Gulf Coast states to along the U.S.- Mexico border.

Hurricane Specialist

SPG Blog Post Day 1

Posted in LightningCast, OCTANE Speed Sandwich, SPG2026 on May 11, 2026 by Kevin Thiel.

Today, the group learned about the suite of satellite products that we will be testing. Below I will include some notes on two of the products we learned about during the operations portion of the day.

Figure 1: LightningCast-ECONUS-compare product

During this exercise, we were placed into two different CWAs: MLB and JAX. I was in the MLB CWA, monitoring developing convection over the FL peninsula, as a frontal boundary moves through to the north. There was a marginal risk, per SPC guidance.
Above is the LightningCast ECONUS comparison product. The top two panels used GOES-19 satellite imagery, while the bottom two panels used MRMS data. The left panels are V1 of LightningCast, and the right panels are V2.
- I noticed that V2 improved on noise reduction, with low percent chances of lightning being more confined to developing storms. V1 seemed to have some low percentages over clouds that looked like low level cumulus, but V2 fixed that.
I really liked how this product highlights areas of active storms, and where the best chances of thunder are next. I find the extent of the LightningCast product to help for DSS purposes, as I have an idea on what areas ahead of the storm should prepare to see lightning.
- The color scale, following SPC categories, works nicely and is easy to interpret, from a forecaster point of view.

Figure 2: Octane CTC

Figure 2 shows the OCTANE Cloud Top Cooling product.
This suite of products became helpful as I began to understand their use.
- The CTC product seems to be very informative on convection development, and differentiating between the various thunderstorm phases. The color scale changes from green, yellow, to red to indicate cloud tops beginning to cool, and are colored at the rate at which they cool every 5 minutes. This way, the user can see where cloud tops are rapidly cooling, and thus where convection is developing/strengthening.
The colormap is relatively easy to understand, from my perspective.
Playing around with the color scale may help to really hone in on developing storms, as from looking around the CONUS, there is a lot of blues and greens. If someone wanted to narrow the scale a little, to reduce the amount of data to sift through, that could help make things a little easier to navigate. I personally don’t mind it, because I think it’s a good way to see general cloud coverage and cloud types.

Kelvin-Helm

Overview: Week 2, Day 1

Posted in Daily Summaries, Lightning Stoplight, LightningCast, OCTANE Speed Sandwich, SPG2026, Synthetic GXI, SZA Imagery on May 11, 2026 by Kevin Thiel.

10 AM

Week 2 of the Satellite Experiment kicked off this morning, with a fresh batch of forecasters and a recharged group of developers. Convection was difficult to find unless you were along the Gulf or Atlantic coasts, and with marginal deep layer shear the potential for severe weather was also also categorized as Marginal from SPC in its 13Z outlook. After our orientation session, the forecast discussion today was focused on western Louisiana, Florida, and the Carolinas. Ultimately we decided to localize to the NWS offices in Jacksonville, FL (JAX) and Melbourne, FL (MLB) with the expectation that upstream convection and land-sea breeze interactions could initiate and sustain convection throughout our operations window (18-22 Z).

1 PM

Operations kicked off with the developers providing hands-on demonstrations and walk-throughs with the forecasters. With a slower severe weather pattern on the first day, we encouraged everyone to think of today as a ‘training day’. Forecasters asked several questions about the synthetic GXI imagery, such as the heights sampled by the 0.91 and 5.15 µm bands, the impacts of snow cover, and how the synthetic products compare to the real 0.91 µm imagery from FCI. We also talked about making RGB products from the synthetic imagery, and realized that the imagery specialists at CIRA had taken the liberty of remapping the products to the ABI 2km grids (kudos!). I’m hoping to create some RGBs this week that we can play with and improve on. What would forecasters like to see in an RGB? Moisture by height? Low level boundaries?

2 PM

We got an MD from SPC! Not a great chance for a watch, but good to know some severe risk exists in our CWAs.

4 PM

The rest of the operations day was pretty slow, so I spent some time working (arguing?) with AWIPS to make an RGB for the Synthetic GXI data. It’s a work in progress…

Found an interesting case of dissipating and initiating convection form the perspective of LightningCast v2 and Lightning Stoplight v2 further west near the Alabama coast. You can watch the probabilities drop and the stoplight transitions from red to green for the dissipating storm, while probabilities increase shortly before the first lightning flashes. Lots of anvil debris to obscure the signal of initiating convection in this example, but there appeared to be at least some lead time by LightningCast before the first lightning flashes appeared from the Lightning Stoplight.

A nice thunderstorm went up east of Jacksonville, with a notable cooling signature from the OCTANE-CONUS Cloud-Top Cooling product. I compared that with the OCTANE-MESO product, and may encourage forecasters to do the same later this week.

To wrap up, I decided to explore all the flavors of the Day Cloud Phase Distinction RGB with a procedure I called ‘oops-all-dcpd’.

Upper Left: GOES-19 CONUS
Upper Right: OCTANE MesoAnywhere (from GOES-19 CONUS)
Lower Left: SZA (from GOES-19 CONUS)
Lower Right: GOES-19 MESO

Kevin

Cirrus over I-10 Cold Front, Cirrus, Anvils: Lake Charles, LA

Posted in Lightning Stoplight, LightningCast, OCTANE Speed Sandwich, SPG2026, Synthetic GXI, SZA Imagery on April 30, 2026 by Kevin Thiel.

Today was a very marginal day as a majority of the CWA was covered in cirrus and then later anvils from nearby thunderstorms. This inhibited much of the solar heating potential with the exception of a small corridor from Lake Charles to Lafayette along I-10. The thermodynamics was not impressive across the area with only 1000 to 2000 j/kg of CAPE. Much of the convective initiation relied on a weak cold front and a sea breeze. There were some thunderstorm complexes that had moved through the area which brought lightning concerns to our two DSS points. Towards the end of the afternoon we were finally seeing convective initiation along the cold front.

With clouds contaminating many of the satellite products, today was mainly focused on lightning cast, lightning stoplight, and seeing how they interact with each other. We found some issues with the stoplight product today. The stoplight product was putting an active grid box that was not co-located with the lightning strike that reported from the lightning detection system. In the image below there is a small purple cross outside of the lone red box.

Final thoughts:

Every product we worked with this week has potential to make an impact. From extending daylight rgb products using a solar zenith adjustment, to using lightning cast and lightning stoplight to help make DSS decisions. OCTANE is a massive improvement for helping to forecast the state of convection. While there are limiting factors like clouds, overall the product could quickly make an impact diagnosing convection and being able to see how correct the models are handling the shear profile. The 0.91 and 5.95 products when operational could be used as ground truth in order to identify the boundaries, and being able to compare that with the models will help with getting those first few storms correct.

-Blizzard

Lightningcast V2 Over Terrain

Posted in LightningCast, SPG2026 on April 30, 2026 by Kevin Thiel.

With a lull in activity over our assigned CWA. I decided to go into CONUS view just to see what was going on across the country. An area that drew my attention was in the Grand Junction CWA. In this area, there were multiple examples of regions with observed lightning from FED and ground based networks, where lightningcast version 2 had little to no probabilities.

Figure 1: Example of FED and ground based lightning detections with contoured lightning cast. Shown are the Grand Junction and Denver CWAs

Figure 2: Example of FED and ground based lightning detections with contoured lightning cast. The Denver CWA is the centered CWA.

-wxboi

EWP Blog

Spring Experiments & Beyond

Category: SPG2026