The National Weather Service Weather Prediction Center posted Tuesday afternoon that "hazardous heat will expand across the Mid-Atlantic and Northeast" through midweek. [1] The cold front the WPC promised arrived in New York and New England by Wednesday evening, which closed the Northeast leg. The Mid-Atlantic leg did not close. Excessive Heat Warnings remained in effect from southern Pennsylvania through northern Virginia, across the central Plains, and into the Inland Northwest, and the WPC's seven-day HeatRisk forecast carried orange ("moderate") and red ("major") values into the weekend in those zones. [2]

Heat Safety Week ends Friday. [3] The week is a National Integrated Heat Health Information System campaign hosted by NWS and CDC; Wednesday's theme was "Check on Your Family, Friends, Teammates, and Neighbors." [3] The paper's May 20 brief on the medicine cabinet still being on the heat list argued the campaign explains hyperthermia in a stranger but not what a 90-degree garage looks like in a refrigerator. The Memorial Day forecast carries the question forward.

Three numbers carry the medicine-cabinet logic. Insulin manufacturers — Eli Lilly, Novo Nordisk, Sanofi — label unopened cartridges for refrigeration at 36° to 46°F and opened pens for room temperature below 86°F (30°C). Above 86°F the chemistry degrades; potency loss is steep above 100°F. EpiPens and Auvi-Q label storage between 68° and 77°F; the inserts allow excursions but ask owners not to leave units in a hot car. Many SSRI, ADHD, and thyroid drugs carry the same range. The Tuesday afternoon high in a closed car parked in the sun in Washington, D.C., was inside the band where every one of these labels asks the patient to act.

Grid demand peaks where the heat is, and the heat is where the medicine is. PJM Interconnection — the regional transmission organization serving from northern Illinois to Virginia — ran demand near its May seasonal record during the Tuesday-into-Wednesday peak; the dome did not pull demand above emergency thresholds. The grid held. The household question on the warning map is therefore not the dome's name. It is whether a household with an insulin user has a battery-backed cooler and a written plan to move pens to a neighbor's refrigerator if power drops for six hours.

USA Today asked Tuesday whether New York's heat was normal for May. [4] The factual answer is that the city's May 90°F days have become more frequent over twenty years and Tuesday's heat-index reading was inside the climatology band. The newspaper-of-record answer was a temperature-curiosity piece. The newspaper-of-readers answer is whether the people who need air conditioning to survive the heat have it.

The CDC and NWS jointly maintain HeatRisk, an experimental seven-day index calibrated against heat-mortality data. The Wednesday-evening update kept the Mid-Atlantic and central Plains at orange and red through Saturday. [2] On the legend, orange means "Moderate — affects those who are sensitive to heat, especially those without cooling/hydration, and some health systems and industries"; red adds "anyone without cooling/hydration." [2] The legend, by category, names the population the medication labels name: the unhoused, the older, the chronically ill, and the medicated.

The Memorial Day grilling stack runs in parallel and against the same households. USDA FSIS guidance is 165°F for poultry, 145°F for whole-cut meats, and 160°F for ground beef. The salmonella outbreak in backyard chickens — 184 cases, 53 hospitalized — is now intersecting heat: the food-safety danger zone (40°F to 140°F) shrinks the working window for a holiday cookout when ambient runs over 90°F. A household with backyard birds, insulin, and a Friday cookout is reading three federal pages at the same time.

The household checklist is uncomplicated and old. Move insulin to refrigerator now. Move EpiPens out of the car. Identify a neighbor with a refrigerator and AC who can hold medicine during a multi-hour outage. Keep meat above 145°F or below 40°F. Drink water before thirst. Check on people who live alone. The Heat Safety Week campaign is correct on every page; the campaign just ends Friday and the Mid-Atlantic warning does not.

-- NORA WHITFIELD, Chicago