29 Nov 2020
Pittsburgh’s November cloud forecasts often leave me scratching my head. What does “Partly Cloudy” mean?
Thanksgiving Day was partly cloudy. See that tiny patch of blue, above? That’s the sunny bit. No, it did not rain.
The official NWS forecast Sky Conditions ought to shed some light (copied below). Though the cloud cover percentages are fixed the names are flexible and disappointing. Mostly Cloudy has two definitions (see italics) and Cloudy is an anemic word for Pittsburgh’s really Overcast skies.
National Weather Service Sky Conditions
Sky Condition | Opaque Cloud Coverage |
---|---|
Cloudy / Overcast | 88% - 100% |
Mostly Cloudy / Considerable Cloudiness | 70% - 87% |
Partly Sunny / Mostly Cloudy | 51% - 69% |
Mostly Sunny / Partly Cloudy | 26% - 50% |
Sunny / Mostly Clear | 6% - 25% |
Sunny / Clear | 0% - 5% |
Something was brewing in the sky below. Would it be Mostly or Partly Cloudy … or Partly Sunny?
An hour later it was calmer and “Mostly” something.
What would the weatherman call this sky condition (below)? Mostly Cloudy? Cloudy? Overcast?
While pondering the answer, look for four crows among the clouds.
(photos by Kate St. John)