Sunday, Aug. 21 & Monday, Aug. 22 Outlook
Tropical moisture interacts with frontal boundary across north Texas; thunderstorms likely for WAS on Sunday then NYC on Mon
Welcome to any new readers! And as a reminder to long-ish time readers, we’re testing a new format for these outlooks. To both old and new—we’re grateful you’re here.
If you have questions about the content of this outlook, the answers might be in this post (we keep adding to it). Otherwise, let us know if something doesn’t make sense (we welcome feedback of all kinds!).
Sunday, August 21
We forecast TSA will screen 2.317 million travelers (± 0.5σ, or a prediction interval of about 38%, is 2.25-2.38 million travelers).
Potential tropical cyclone 4 is currently located over the southwestern Gulf of Mexico and moving northwest at 12 knots. While the system is forecast to reach the coast near the mouth of the Rio Grande later today, it looks to pump tropical moisture northward into early next week. Across northern Texas (read: DFW), a slow-moving frontal boundary should provide the trigger for widespread shower and thunderstorm activity.
Meanwhile, the system set to impact the Chicago area this afternoon will expand shower and thunderstorm coverage into the Ohio Valley yet today then the Mid Atlantic on Sunday (i.e. probabilities for DCA feel1 a little underdone).
Monday, August 22
We forecast TSA will screen 2.238 million travelers (± 0.5σ, or a prediction interval of about 38%, is 2.17-2.30 million travelers).
A frontal boundary south of the NYC area slowly moves northward on Monday, likely producing showers and thunderstorms.
You can check out2 hourly estimates in this workbook.
Yamaç, no doubt, is shaking his head at Tim and his feelings.
While it links to a Google Sheet, it’s an Excel file and relies on the XLOOKUP function, which does not exist in Sheets. You can download the file and open in Excel, which should resolve the #NAME? error; if any readers don’t have Excel, let us know and we can work on a solution.