GOES-18 (GOES-West) and GOES-16 (GOES-East) True Color RGB images from the CSPP GeoSphere site (above) showed hazy arcs of blowing dust lofted by Tehuano gap winds that emerged from the south coast of Mexico — which spread out across the Gulf of Tehuantepec and the adjacent waters of the Pacific Ocean on 16-17 January 2024.

GOES-16 Visible images on 16 January (below) included surface plots, Metop ASCAT winds and surface analyses. The development of Gale Force winds was being forecast for the Gulf of Tehuantepec, as northerly winds behind an approaching arctic cold front accelerated through the Chivelas Pass (topography) before exiting the southern coast of Mexico near Ixtepec (MMIT).

As the strong arctic cold front moved inland across the northern coast of Mexico, a notable drop in temperature and dew point was seen at Veracruz (MMVR) and Minatitlan (MMMT), with northerly winds gusting to 45 knots at Veracruz (below).

Surface winds derived from Metop-B/Metop-C ASCAT and GCOM-W1 AMSR2 (source) showed the intensification of Tehuano gap wind flow (below) — the presence of Gale Force winds (34-47 knots) in the Gulf of Tehuantepec was confirmed by both ASCAT and AMSR2.

Significant Wave Height values up to 11.66 ft were generated by these Gale Force winds, according to CryoSat-2 altimetry data (below).

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LightningCast probability fields are routinely produced at CIMSS and incorporated into a RealEarth display (LightningCast probability fields are also available in some National Weather Service AWIPS machines). An example of LightningCast is shown below over Southern Florida. Contours show the probability of a GLM observation of lightning within the next 60 minutes: 10% (Blue), 20% (Cyan), 50% (Green), 75% (Magenta).

Scientists/Programmers at CIMSS are working on a CSPP Geo package that will create LightningCast probability fields, both current and historical. The software has the ability to subsect data, so full-disk (or full-CONUS for GOES-16 or full-PACUS for GOES-18) imagery need not be created. An example of the output for the same times and location as the RealEarth display is shown below.

The animation below stacks both the CSPPGeo and RealEarth output. There are minor differences that are being investigated.

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If you are at the AMS 2024 Meeting in Baltimore at the end of January, you can learn more about LighningCast at this talk on Thursday, 4:45-5 PM, in room 336. A LightningCast Probability QuickGuide is available here.

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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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