The image above (from 2100 UTC on 28 February 2022) and below (from 0930 UTC on 1 March 2022) toggle between low-level estimates of 1000-mb dewpoint and GOES-16 IFR Probability fields. Is there a general relationship between the two? At first blush, it does seem like the IFR Probability fields are affected by the strong gradient in low-level temperature, where the dewpoint drops from the teens (^oC, grey/blue to cyan in the enhancement) to the single digits (purple and white in the enhancement). Note that SSTs in the region where the 1000-mb dewpoints are in the single digits are between 10 and 14 C at both ~2100 UTC 28 February and ~0930 UTC 1 March (ACSPO SSTs at the link are derived from Direct Broadcast data from CIMSS and are available via an LDM feed).

The toggle below compares gridded NUCAPS estimates of 1000-mb relative humidity with Low IFR Probability fields. There again seems to be a relationship. How robust that relationship is is to be determined. This is the first in a series of blog posts that compares these two fields, as part of a way of better forecasting fog over the oceans.

AWIPS imagery in this blog post was created using the NOAA/NESDIS TOWR-S AWIPS Cloud Instance.

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GOES-16 (GOES-East) “Red” Visible (0.64 µm), Near-Infrared “Cirrus” (1.37 µm), Mid-level Water Vapor (6.9 µm) and “Clean” Infrared Window (10.3 µm) images (above) displayed a pattern of transverse cloud banding over parts of the Upper Midwest on 28 February 2022.  This type of transverse banding is often a signature of an enhanced potential of middle- to high-altitude turbulence — so not surprisingly, there were several pilot reports of light to moderate turbulence in the vicinity of these cloud bands.

A closer view of the transverse banding over Minnesota and Wisconsin at 2301 UTC is shown below.

Hourly GOES-16 Near-Infrared “Cirrus” images with contours of RAP40 model Maximum Wind isotachs (below) indicated that this pattern of transverse banding was occurring within the left exit region of an anomalously-strong anticyclonically-curved upper tropospheric jet streak — consistent with the findings of a study by Trier and Sharman.

Such transverse banding cloud features are frequently observed around the periphery of decaying MCSs (for example, July 2020 , June 2018 and July 2016) and in the vicinity of strong upper-tropospheric jet streaks (for example, February 2020 and March 2016).

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A squall warning was issued for areas of southern Quebec and Ontario as well as New York, Vermont, New Hampshire, and Maine on Sunday, February 27, 2022. The eastward moving system was surrounded by a lower deck of organized stationary wave clouds as seen in this high-resolution GOES-16 Band 2 video. The snow brought whiteout, zero visibility, conditions and wind gusts up to 40 mph.

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JMA Himawari-8 “Clean” Infrared Window (10.4 µm) images (above) displayed the Fujwhara effect between Cyclone Vernon (which rapidly intensified and briefly developed a small eye) and Tropical Invest 93S, as they rotated (clockwise) around each other in the South Indian Ocean — west of Cocos Island, station identifier YPCC — during the 25 February – 27 February 2022 period. Invest 93S was eventually absorbed by Vernon (which decreased in intensity during the absorption  process).

Himawari-8 “Red” Visible (0.64 µm) images (below) showed Vernon when it had reached a peak intensity of Category 3 (ADT | SATCON) — however, the eye remained cloud-filled during that time.

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