The 1200 UTC sounding from Hilo HI (91285) was unavailable on 29 October 2024. (Here is the sounding from 0000 UTC). When such a failure happens, there is a backup: NUCAPS profiles show thermodynamic information that is retrieved from infrared and microwave information on NOAA-20, NOAA-21 and MetopC satellites, and a profile is usually available around 1200 UTC in Hawaii. The plot below shows available NUCAPS plots over Hawaii at 1144 UTC, 29 October. Note the yellow dot over Hilo; Yellow typically means the infrared retrieval failed to converge, and the profile information is therefore coming from microwave data. (Green points show profiles where the infrared solution converged to a solution.) The profile from the yellow point over Hilo is below.

The NUCAPS profile at Hilo, below, shows a relatively moist boundary layer, a strong inversion with a top near 750 mb, and relatively moist air between 300 and 500 mb. In the Sounding Availability plot above, profiles that did converge to a solution are located northwest of Hilo, just offshore of the Big Island, and to the east of Hilo. Those profiles are shown below. They show features similar to the profile at Hilo.

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When fate interferes with your ability to view rawinsondes, NUCAPS can step in and help. A good practice is to compare the profiles when rawinsondes are present so you can better understand how they compare.

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The Storm Prediction Center’s Fire Weather Outlook, issued at 1700 UTC on 28 October (link), shown below, shows a critical weather day over portions of Oklahoma, Kansas and Texas. The forecast office in Norman, OK, noted the fire risk, Red Flag Warnings and Wind Advisories on its front page.

The Next Generation Fire System Alerts Dashboard monitors satellite imagery to detect the hot spots that indicate wildfires. A screen capture of the Alerts Dashboard is shown below (The Alerts Dashboard has been modified so only alerts in TX and OK are shown), with an alert shown for Logan County in OK, north of Oklahoma City OK. By clicking on the triangle, satellite data associated with alert can be accessed.

The satellite imagery revealed once a user clicks on ‘Satellite Imagery’ above is shown below. This shows the NGFS Microphysics RGB. In addition, the pixels where the fire has been detected are highlighted; the color of the pixel outline is a function of the estimated GOES-R derived Fire Radiative Power. The slider allows a user to move forward and backward in time to help conclude if action is required. Note also the button that says ‘Open in RealEarth’. That opens a RealEarth instance that includes all the NGFS fire products.

The RealEarth instance of NGFS, for the same time, is shown below.

The animation below shows Fire Temperature RGB and NGFS Microphysics RGB animations from 1721 to 1836 UTC. The fire detection in both RGBs shows up at 1746 UTC. High clouds mean it is a challenge to maintain the RGB signal, but the NGFS signal persists as high clouds move overhead.

CSPP Geosphere true-color imagery, below, shows a complicated scene. The moving high clouds make it difficult to identify — visually — any fire detections.

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The CIMSS Prototype NGFS website is here.

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GOES-18 Airmass RGB imagery, above, from 1500-1820 UTC on 28 October, show light snow over much of central Alaska as a storm system moves into the state. Temperatures at 500 mb, below, derived from NUCAPS profiles (as shown in the toggle), show a tongue of warmer air positioned with the cloud feature (shown as white) in the RGB above. Temperatures in that warm(ish) tongue of air (bluish in the enhancement) are around -25 to -27^oC versus the Bering Sea (magenta in the enhancement) where they are around -35^oC. Temperatures at 850 mb over the Bering Sea (shown here with a color enhancement that ranges from -25^oC to +10^oC) are around -6^oC.

Snowfall Rates, estimated from ATMS on Suomi-NPP (from this site) show snow moving slowly north between 1324 and 1504 UTC over western Alaska.

Did your eye jump on the heavier Snowfall rates over southern Alaska? The region around Anchorage is in a Winter Storm Warning; 6-12″ is expected, more than the lighter values expected across the central part of the state.

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Infrared imagery over the Hawai’ian Islands on 25/26 October, below, shows convective development over Maui and Oahu. This was also a region of strong vertical wind shear, as shown below, as upper level cloud features were moving southeastward, low level clouds were moving to the west).

GREMLIN is a machine-learning tool that uses Bands 7, 9 and 13 fields from GOES-18 to emulate what NEXRAD radar echoes might look like. The animation below shows GOES-18 infrared data, and GREMLIN radar estimates. GREMLIN shows radar returns over both Oahu and Maui.

Strong convection with radar returns occur over both Maui and Oahu after 1500 UTC. The National Weather Service in Honolulu issued Flash Flood Warnings at 1638 UTC for Maui and at 1640 UTC for Oahu. The side-by-side animation, from 1501-1701 UTC shows the heavy rain indicated by GREMLIN as the Flash Flood Warning was issued.

The Hilo sounding from 1200 UTC on 26 October, below, (from here) shows a moist atmosphere (55 mm of Total Precipitable Water) and mid-level instability. MIMIC Total Precipitable Water (TPW) at that time (here) shows the horizontal distribution of the moisture.

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