As a strong arctic cold front moved southward across the Gulf of Mexico toward southern Mexico on 12 March 2026, the cold front fractured as it moved inland across Mexico’s Isthmus of Tehuantepec — the cold air was then channeled southward through Chivela Pass and emerged as a Tehuano (or “Tehuantepecer“) gap wind that eventually fanned outward across the Gulf of Tehuantepec and the adjacent Pacific Ocean. 10-minute Full Disk scan GOES-18 (GOES-West) and GOES-19 (GOES-East) True Color RGB images from the CSPP GeoSphere site (above) showed the hazy plume of dust that was being transported offshore by the Tehuano flow.

A GCOM-W1 AMSR2 wind speed image (below) displayed the leading edge of the Tehuano winds (shades of green) as they began flowing southward across the Gulf of Tehuantepec.

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Kilauea on the big island of Hawaii is renowned for its new-continuous eruptions. However, the output of the volcano isn’t consistent, with some periods featuring slower lava flows with other times having pronounced, notable lava fountains. On 10 March 2026, the lava fountains were particularly intense. Local media reported fountain heights approaching 1500 feet (450 m) tall, measurable ashfall accumulation, and tephra (volcanic ejected material) up to three inches in diameter. The US Geological Survey notice about this event can be read here.

Just as the Band 7 (3.9) micron channel from the GOES Aadvanced Baseline Imager (ABI) is well-suited for fire detection, it is also quite useful for volcano monitoring. The following animation shows the 3.9 micron channel for the period both before and during the appearance of the fountains. The existing eruption is visible as the dark spot on the southeast side of the big island of Hawaii. However, with the fountains beginning between 1900 and 2000 UTC (9:00 to 10:00 AM local time) the bright spot gets so hot that it saturates the scale and appears as a bright white dot that is occasionally obscured by the optically thick ash plume.

Of course, ash is a real concern with an eruption like this, due to the impacts it has on human health and aviation safety. The GOES Volcanic Ash RGB helps monitor the evolution of the ash plume. The following animation is for the same period as the one above, but for this RGB product. The bright green plume is easy to see. Plumes with this color are high in SO₂. Hawaiian airlines reacted to this threat by cancelling its Honolulu to Hilo flights and diverting others to Kona.

The Community Satellite Processing Package (CSPP) calculates Level 2 products from both geostationary and polar orbiting satellites. The CSPP GeoSphere site enables the display of these products. Here’s a move of the aerosol optical depth. Note that this product is only available in otherwise clear skies and during the day, so there are gaps in the retrieval when clouds are present. Still, it shows the evolution of the ash plume from this eruption before it gets overtaken by both clouds and night.

The NEXRAD radar on the south shore of the big island captured the ashfall, too. This animation depicts the evolution of the ash cloud as seen by both the standard reflectivity (left) as well as the correlation coefficient (right). That latter panel depicts a large plume of non-spherical scatterers, consistent with the irregular shape of ash and tephra.

The radar can also be used to investigate just how high the ash plume went. Here is an animation of the different elevation angles of the radar at a single time, 21:58 UTC. The elevation angle, ranging from 0.5 to 3.1 degrees, can be seen in the lower right of the image, just to the left of the time.

Finally, the GOES-18 mesoscale sector scan was deployed to Hawaii during the middle of the eruption to capture it as well as the ongoing Kona low that was bringing rain and flooding to parts of the state. This gives us some fantastic views of the plume. Here it is in both the true color and volcanic ash RGB products.

This particular event ended around 6:30 PM local time (0430 UTC on the 11th), but there may be more fountain events in the future.

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1-minute Mesoscale Domain Sector GOES-19 (GOES-East) Visible and Infrared images with time-matched plots of SPC Storm Reports (above) showed thunderstorms that produced several tornadoes and numerous reports of hail — most notably, as large as 6.10″ in diameter near Kankakee, Illinois at 2328 UTC. If verified, that would be the largest hailstone on record for the state of Illinois (NWS Chicago event summary).

1-minute GOES-19 Visible images (above) and Infrared images (below) included an overlay of GLM Flash Points, which showed abundant lightning activity with these severe thunderstorms.

A toggle between GOES-19 Visible and Infrared images at 2100 UTC (below) showed an “orphan anvil” that was drifting to the northeast (located just north of the Chicago NWS forecast office, identifier KLOT, at that time) — which had developed around 2030 UTC, as the convective cap was beginning to erode just north of a cold front (orphan anvils often appear shortly before the onset of significant convective development, signalling that convective inhibition is weakening).

A toggle between GOES-19 Visible and Infrared images at 2259 UTC (below) displayed well-defined Enhanced-V and Above-Anvil Cirrus Plume (AACP) signatures, extending downwind (eastward) from a prominent overshooting top (cluster of darker black infrared pixels, exhibiting brightness temperatures as cold as -73ºC) over northeast Illinois. As the thunderstorm exhibiting the Enhanced-V/AACP signature crossed border from Illinois to Indiana around 0008 UTC, it produced a tornado that was responsible for 2 fatalities.

The coldest cloud-top infrared brightness temperature of -73ºC roughly corresponded to a ~2 km overshoot of the Most Unstable (MU) air parcel’s Equilibrium Level (EL), according to a plot of rawinsonde data from Lincoln, Illinois (below).

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While Chicago O’Hare recently retook the crown of the country’s busiest airport in terms of number of flights, Atlanta’s Hartsfield-Jackson International Airport (ATL) continues to have the largest number of passengers. A great number of those ATL passengers were significantly inconvenienced on the evening of 6 March 2026 as a hailstorm passed directly over the airport just before 7:00 PM (0000 UTC on the 7th), one of the busiest times of the day for outbound flights. While the hail was not particularly large (no reports made it to the Storm Prediction Center’s Storm Reports for the day) it still forced a ground stop and inspections of dozens of aircraft to ensure that passengers were able to continue safely. Those inspections were hampered by the continued presence of lightning which kept crews indoors for their own safety. It took many hours for planes to be cleared for departure; hundreds of flights were cancelled and the ripples of this are still impacting flight operations the next day.

The atmosphere was somewhat primed for convective activity on this day. A NUCAPS profile near Atlanta from NOAA-20 at 1917 UTC (2:17 PM EST) as plotted by NASA SPoRT’s NUCAPS Savvy site is shown below. Note the presence of steep low-level lapse rates that are contributing to a decent level of surface-based CAPE (1486 J/kg).

The GOES-19 10.3 micron Band 13 view of the event is shown below. The hail event wasn’t the first storm to hit ATL that day, as a previous round of convection had already caused a ground stop earlier. The following loop begins just after the first round moved off to the east and captures the second round from initiation onward. The convection isn’t particularly deep, as can be seen in the relatively warm cloud top temperatures (you can also discern that in the NUCAPS profile above where the tropopause appears to begin around 280 mb or so).

Despite the somewhat low cloud tops, the presence of a vigorous updraft can be discerned with the presence of an enhanced V. We’ve highlighted below in the 2346 UTC frame; just move the slider back and forth to add or remove our subjective annotation.

CIMSS’s ProbSevere Product was also tagging this storm as one to watch, as shown in the following loop (the airport can be found at the right angle in the county boundaries in the center of the image).

Here’s what the ProbSevere metrics for this storm were. There’s an important caveat here: this was not a “severe” hail event, in that hail did not meet or exceed the 1 inch threshold that the National Weather Service has defined for hail to merit the severe designation. There do not appear to be any reports of damage to the planes, which is consistent with this “less than severe” designation. ProbSevere is calibrated to predict the probability of severe events. Therefore, while this 45% probability might seem small for an event that had such a significant impact, it is consistent with what actually took place.

The CIMSS LightningCast product was also monitoring this event. In addition to contour plots overlaid on satellite imagery, LightningCast also provides dashboards at key locations across the United States, including stadiums and airports. Here’s what the LightningCast dashboard for ATL looked like (red) alongside verification from the GOES-19 Geostationary Lightning Mapper. It was clear that lightning was going to hinder ground services.

One challenge with monitoring this event was that it occurred right around sunset, which meant that most of the RGB products used for convection monitoring were not reliable: it was too dark for the daytime products, but there was still too much reflectance in the 3.9 micron band for the nighttime products to be useful. Still, the panoply of other satellite products made it possible to monitor the evolution of this not severe, but still significant, event.

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