Upper-level water vapor imagery, above, shows the development of standing waves in the lee of the Hawai’ian islands. (The waves were also apparent in mid-level and low-level water vapor imagery). Wave development as shown above requires a perturbation in the vertical — achieved by southwesterly flow in the atmosphere encountering the higher terrain of the islands — and an inversion layer along which the gravity wave will propagate. The Lihue sounding at 1200 UTC on 16 January 2024, below, shows an inversion just above 850 mb, and also one near 570 mb. The higher inversion is likely the one that is trapping the wave energy.

The 6.19 µm Weighting Function (viewable at this CIMSS website) for the Lihue Sounding at 1200 UTC on 16 January 2024, below, shows much of the contribution sensed by the satellite to come from the layer between 400 and 600 mb (with a peak contribution at 535 mb). The warm/cold couplet in the observed waves in the water vapor animation above is from -21 to -24^oC. The Lihue sounding had temperatures in that range around 350 mb.

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The development of the standing waves coincided with very strong winds near Kaneohe bay on the northeastern shore of Oahu. The Meteorogram below shows observations from Marion E. Carl Field (the Marine Corps Air Station PHNG). Gusts exceeded 30 knots for 9+ hours starting at 1500 UTC.

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The toggle of true-color MODIS imagery above, (taken from the MODIS Today website) shows Terra MODIS imagery on 14 and 15 January 2024. The 14th was the first day of an Arctic outbreak over deep snowcover in the upper Midwest; Madison WI was at/below zero the entire day. As a consequence, many lakes that were open water on the morning of the 14th (when Terra overflew WI around 1600 UTC) were ice-covered on the morning of the 15th (when Terra overflew WI around 1630 UTC). The image below shows the 14 January imagery with some lakes named. In particular, Lake Monona and parts of Mendota froze between the 14th and 15th; many of the lakes northwest of Pewaukee Lake froze; Delavan Lake froze. Green Lake, Lake Mendota and Lake Geneva are all quite deep and therefore somewhat resistant to quick freezing, but will likely freeze over soon given the forecast.

GOES-16 animations (taken from the CSPP Geosphere site) from 14 January (above) and 15 January (below) also show the change in ice coverage.

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Mid-January is on the late side for lakes to freeze over Wisconsin. A warm December is to blame! Part of this is due to the ongoing Strong El Nino. In 1982-1983, a strong El Nino (as depicted at the start of this video; also shown here) similarly delayed Mendota’s freezing to mid-January.

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A distinct hot thermal signature (black to yellow to red pixels) of the Hagafell-Grindavik fissure eruption in southwestern Iceland was apparent in GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) imagery on 14 January 2023 (above). Station identifier BIRK is Reykjavik Airport, and BIKF is Keflavik International Airport.

Since the fissure eruption and subsequent lava flows began during the nighttime hours, the thermal signature also showed up well in GOES-16 Near-Infrared 1.61 µm and 2.24 µm imagery (below).

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1-minute Mesoscale Domain Sector GOES-18 (GOES-West) images from all 16 of the ABI spectral bands (above) displayed signatures of a SpaceX Falcon 9 rocket that was launched from Vandenberg Space Force Base, California at 0859 UTC on 14 January 2024. Either a reflectance signature or a warm thermal signature of the Stage 1 rocket booster was evident in images from 15 of the 16 spectral bands (Bands 02-16) — and a signature of the low-altitude rocket launch condensation cloud was seen in Shortwave Infrared and Infrared spectral bands 07-16 as it drifted eastward.

A close-up view using 16-panel displays of all GOES-18 ABI spectral bands (below) showed that either a reflectance or a thermal signature of the Stage 1 rocket booster was evident in most of the Visible and Near-Infrared bands (02/03/04/05/06) at 0900 UTC, along with a warm thermal signature in Infrared bands 07/08/09/10/16. After that time, a colder thermal signature of the rocket launch condensation cloud was seen in Bands 07-16 as it drifted eastward.

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