Messages
A cold high pressure system will bring dry weather and below normal temperatures to the region through the weekend into early next week. Temperatures will slowly climb back to around seasonal normals by the middle of next week.
Plaincast — the National Weather Service forecast, decoded into plain English
Plaincast
What the forecast actually says — NWS Area Forecast Discussions, decoded into plain English.
Plaincast decodes the National Weather Service's Area Forecast Discussion — the real forecast, written 3 to 4 times a day by the meteorologist on shift — into plain English. The discussion is where a forecaster explains their reasoning: which models disagree, what they are watching, and how confident they are. Below is the current edition for St. Louis, with its shorthand expanded. The full experience — an AI plain-English summary beside the annotated original — loads with JavaScript, and every one of the 68 forecast offices has its own edition.
Short Term
A high amplitude blocky pattern is setting up across the CONUS with a deep long wave trough over the eastern U.S., a ridge over the Plains, and another trough west of that. The eastern trough is dragging a high pressure system southward from Canada into the Mississippi Valley with what looks like the coldest temperatures so far this season. Upstream temperatures across Iowa and southern Minnesota topped out in the upper 30s to mid 40s Thursday afternoon, and this air is moving into the Mid Mississippi Valley today. Guidance is giving us highs in the mid 40s today, and this looks reasonable given the upstream temperatures, accounting for a bit of airmass modification and somewhat stronger insolation with less cloud cover today.
Winds will diminish tonight as the high continues building into the Midwest, and the latest model guidance shows a mostly clear to clear sky. The light winds and lack of cloud cover will be ideal for radiational cooling which will allow temperatures to drop into the low to mid 20s across most of the area. Wouldn't be surprised to see upper teens in some of our cold spots like Rosebud MO. temperatures rebound into the 40s again Saturday afternoon under full sunshine and light winds with the ridge axis overhead.
This is the plain-text edition, decoded without AI so it loads anywhere. Read the whole St. Louis discussion at /o/LSX/, see what changed since the last one, or open The National Desk for where the weather is today.
Data from the National Weather Service. Translated by Claude. About · For developers & agents · Subscribe: RSS feed for this office · Source on GitHub