The National Weather Service offices in much of the central and western continental United States have modified their radiosonde launch times. Instead of the standard synoptic times of 0000 and 1200 UTC, these offices have shifted that latter time to 1800 UTC. Since radiosondes are labor-intensive, this change to the middle of the day helps ensure that sufficient staffers are around to launch the balloon and maintain operational readiness. Here, courtesy of the NOAA Storm Prediction Center, is a slider juxtaposition of a map of the 1200 and 1800 UTC radiosonde launches showing how the majority of the missing 1200 UTC sites are instead showing up at 1800 UTC.

Of course, if you are used to looking for radiosondes at certain times, this shift might be disruptive to your workflow. Here’s a case where satellites can once again come to the rescue by helping to fill in those gaps. This blog has frequently talked about the advantages of the NUCAPS product, in which combined infrared and microwave sounders deliver vertical profiles of temperature and dew point from the polar orbiting NOAA-20 and NOAA-21 satellites. While they don’t give the same vertical resolution as the radiosondes, they make up for it in observational density. Here’s an animation of the distribution of NUCAPS profiles across North America from the NOAA LEO satellites. Remember, this can be used as a proxy radar: green is where both infrared and microwave satellite retrievals are available and thus are indicative of clear skies; yellow is where microwave is available but infrared isn’t, and thus shows where the skies are cloudy, and red is where neither infrared nor microwave are valid and thus shows where it is raining. This animation shows roughly 18 hours of NUCAPS availability over CONUS, from 0000 UTC on Sunday the 14th to 1800 UTC on the 15th.

Of course, the temporal gaps cannot be ignored. One thing to do is use the GOES Legacy Atmospheric Profile (LAP) products instead. These are not going to have the same vertical detail as the NUCAPS soundings because they don’t have the same information content. While there are many hundreds of channels from the infrared CrIS sounder, the GOES LAP product just uses the ABI channels. This results in a reduced ability to capture small-scale features compared to the hyperpsectral CrIS sounder. At the same time, there’s no microwave instrument in geostationary orbit. This means that GOES soundings can only happen in locations where skies are clear since clouds are opaque to infrared radiation and thus block all radiation originating from the surface. However, unlike NUCAPS, the GOES soundings have far greater temporal availability given their basis in geostationary observations.

A little over a year ago, we wrote a blog post discussing the LAP products, and we encourage you (and NWS users in particular) to check it out to see how to access these soundings and learn about their applications and limitations.

The next generation of US geostationary satellites, GeoXO, promises to unite the vertical resolution of the existing LEO satellites with the temporal resolution of geostationary orbit. The GeoXO Sounder (GXS) will provide hyperspectral observations from geostationary orbit, drastically improving both the temporal and spatial resolution of the sounding observations. Similar observations are already underway from EUMETSAT’s MTG-IRS and China’s GIIRS, and we can expect Japan’s Himawari-10 to be operational in the coming years as well. It is truly an exciting time for people, like your author, who are fans of hyperspectral thermodynamic profiling!

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5-minute CONUS Sector GOES-19 (GOES-East) Infrared Window images combined with the Total Precipitable Water derived product in cloud-free regions (above) showed clusters of thunderstorms that produced heavy rainfall across parts of central Texas shortly after sunset on 14 June 2026. Significant flash flooding affected the Waco area — which temporarily closed a portion of Interstate 35 near Waco, stranding vehicles with a few water rescues being required. 1-hour precipitation amounts at Waco were as high as 1.68 inches.

Multiple Flood Advisories and Flash Flood Warnings were issued as the thunderstorms expanded eastward and southward across Central Texas (below) — for the Waco area, the initial Flash Flood Warning was issued at 0054 UTC.

The coldest cloud-top infrared brightness temperature exhibited by these thunderstorms was -81.03C at 0041 UTC (above) — according to a plot of rawinsonde data from Fort Worth (below), that temperature represented an altitude near the Maximum Parcel Level (MPL) of the Forecast Surface (FCST SFC) air parcel.

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On the afternoon of 11 June, 2026, a fire broke out at a medical supply warehouse in Tracy, California, in the central part of the state. The fire quickly consumed the nearly million square foot facility. While our weather satellites are frequently used to identify and monitor wildfires, they can also do the same for human-built structures as well.

Let’s begin by taking a look at the GOES-19 (GOES West) true color view. This loop runs from 2000-2200 UTC (1 PM – 3 PM local time). The fire is easy to identify from the large plume of thick, black smoke that erupts from the center of the image before being advected southward.

Of course, other spectral bands can show some unique perspectives of the image. Here is the Fire Temperature RGB product. Note the bright red spot in the center of the loop that appears just before the darker smoke plume arises.

As this blog frequently discusses, the 3.9 micron channel is a must-see tool for early identification of fire, and this event is no exception. It’s easy to see the moment the fire erupts thanks to the appearance of a dark (hot) spot at this channel.

These geostationary images are quite useful for fire detection as they are temporally continuous. With geostationary observations at all channels available every 5 minutes over the continental United States, it’s easy to capture the temporal evolution of events. While polar orbiting overpasses are comparatively rarer, they make up their temporal sparseness with much higher spatial resolution. Fortunately, there was an overpass by NOAA-20 as the fire was intensifying.

Courtesy of the CIRA Slider viewer, here is the Fire Temperature RGB Product as seen by the VIIRS overpass at 2040 UTC. Compare this to the fire temperature image above: note how the pixels in VIIRS are both smaller and hotter. The change in fire temperature is a function of how the radiant energy is distributed in the different pixel sizes. At 2 km, the geostationary pixels are capturing plenty of non-burning space and thus the areal average of the radiant energy, while higher than any non-burning pixel, will still be lower than the fire itself.

By contrast, the VIIRS pixels are only 375 m across. If we look at the size of the building in question on Google Maps, we see that it’s about 630 m long, or approximately two VIIRS pixels side by side. The rectangular shape of the building appears to be reflected in the shape of the hot-to-very hot fire pixels above. These pixels are small enough that they are mostly filled with fire, and with little non-fire area to bring down the average, this is marked as “very hot” by the RGB recipe.

While the building is a total loss, fortunately there were no reports of injuries among the workers.

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1-minute Mesoscale Domain Sector GOES-19 (GOES-East) Visible and Infrared Window images (above) included time-matched plots of SPC Storm Reports — which showed supercell thunderstorms that produced several tornadoes, hail as large as 2.50″ in diameter and wind gusts as high as 85 mph across parts of northern/central Illinois and far northwestern Indiana on 11 June 2026. Of the 11 confirmed tornadoes so far, initial storm surveys have found EF3 damage in Streator, Illinois and from Hebron to Kouts, Indiana.

1-minute GOES-19 Visible and Infrared Window images that included plots of GLM Flash Points (below) highlighted the abundant lightning activity associated with these thunderstorms. Surface observations also supported the satellite depiction of a relatively cloud-free cold pool (created by outflow from a decaying convective complex across northeastern Illinois earlier in the day) — and the upscale growth and tornado production of discrete supercell thunderstorms appeared to increase as they moved eastward and interacted with that residual boundary.

Plots of rawinsonde data from Lincoln, Illinois (location) at 1800 UTC and 2100 UTC (below) displayed a marked increase in the atmosphere’s instability and shear parameters during that 3-hour period — and an elevated mixed layer became well-defined. At the surface, Lincoln was located within the warm, moist air that was surging northward toward the aforementioned residual convective outflow boundary.

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