Daily Archives: October 12, 2020

IFR Probability near a major aviation hub

GOES-16 IFR Probability, 0926 – 1101 UTC on 12 October 2020 (Click to enlarge)

The New York City area has 3 major international hubs for which ceiling/visibility observations and prediction are critical to efficient operations. IFR Probability fields use both satellite data and Rapid Refresh model data and can supply information about low-level conditions even where mid-level or upper-level clouds obscure a satellite’s view of low clouds. The example above shows very slow northeastward progress of an area of potential IFR conditions towards New York.

Satellite-only data, below, in the form of the night fog brightness tempreature difference from GOES-16, does not give a useful signal for the low clouds along the east coast. A conclusion: Use IFR Probability to monitor the progress of low clouds when multiple cloud decks are present.

GOES-16 ‘Night Fog’ Brightness Temperature Difference (10.3 µm – 3.9 µm) field, 1006-1101 UTC, 12 October 2020 with 0900 UTC frontal analysis overlain on first image (Click to enlarge)
GOES-16 IFR Probability and GOES-16 ‘Night Fog’ Brightness Temperature Difference (10.3 µm – 3.9 µm) field, 1101 UTC, 12 October 2020 (Click to enlarge)

The toggle above, between IFR Probability and the Brightness Temperature Difference demonstrates and underscores (1) how IFR Probability can fill in regions under low clouds (in Delmarva and New Jersey, for example), and screen out regions with mid-level stratus (over eastern Lake Ontario the surrounding land, and over eastern Ohio, for example).

IFR Probability fields are supplied to AWIPS (TOWR-S Build 19) via the SBN.