National Weather Service
Why Thunder Sometimes Cracks and Sometimes Rumbles
The same lightning bolt can sound like a gunshot or a drumroll depending on how far away it struck. Here's the physics behind both.
Graupel vs. Hail: The Difference Is in How Cold It Got
It looks like hail and sounds like hail — but squeeze it, and graupel crumbles like styrofoam because it forms almost the opposite way.
Why Your Windshield Frosts Over When It's Above Freezing
Frost can form on a windshield when the forecast still reads in the upper 30s. The gap comes down to where, and how, temperature is actually measured.
Why Thunder Cracks Up Close but Rumbles From Far Away
A single lightning bolt can sound like a sharp crack in one spot and a rolling rumble a few miles away, and the split comes down to how far its miles-long channel is from your ear.
Corn Sweat, Explained: How Cornfields Turn Up the Heat Index
Evapotranspiration — corn's version of sweating — is quietly making already brutal Midwest heat waves feel worse, and meteorologists say the effect is only ramping up for the season.
Why Winter Storms Get Named — and the National Weather Service Won't
The Weather Channel has named winter storms for 14 seasons running, using a population-and-area formula it built itself. The National Weather Service — and the AP — still won't use the names.
Heat Advisory vs. Excessive Heat Warning: What the Words Mean
The same alert can mean 100 degrees in one city and 105 in the next, because heat-index thresholds are set locally, not nationally.
Fire Weather Watch vs. Red Flag Warning: Why the Gap Matters
One alert gives you up to three days of notice. The other means the National Weather Service thinks conditions are already dangerous enough to spread a fire fast. Confusing the two can cost the exact hours evacuation guides say matter most.
Heat Advisory or Extreme Heat Warning? What the NWS Renamed in 2025
The National Weather Service quietly retired "Excessive Heat Warning" in 2025. Here's what the new terms mean, and the exact thresholds regional offices use to issue them.
Wet bulb, heat index or dew point: which number matters
Three humidity-adjusted heat numbers dominate the summer forecast, and they answer different questions. The one everybody quotes assumes you are standing in the shade.
Category 5 Typhoon Bavi Closes In on Guam With 160 mph Winds
Shelters are filling and the ports are shut as a Category 5-equivalent storm bears down on Guam and the Northern Mariana Islands, with landfall due Monday.
Heat Dome Threatens Record Highs From D.C. to New York by July 4
More than 165 million Americans face major or extreme heat risk this week as a record-threatening heat dome settles over the East Coast and Midwest through the July Fourth weekend — and complicates World Cup matches.