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Could the nation’s television meteorologists ease up on the drama?
A little drizzle now seems to require forecasters to zoom ominously across their maps while warning that much of the country could soon face bomb cyclones, thundersnow, firenados, derechos, macrobursts and rapidly intensifying haboobs.
Maybe the theatrical language helps ratings. There is, let’s say, a 47.23% chance of that developing within the next two to four hours.
The forecasts can sound apocalyptic: “gorilla hail” and super typhoons sweeping along atmospheric rivers, followed by avalanches, mudslides, wildfires, power failures and delayed school openings. The European Model inevitably makes an appearance, too, though viewers are never shown her photograph.
On Sunday at precisely 12:38 p.m., News 8 Chief Meteorologist Eric Snitil of Rochester, New York, offered a prime example on Facebook.
Snitil warned that a powerful Great Lakes low expected Monday could become a “bomb cyclone,” explaining that the cartoonish-sounding phrase is a real term for rapid cyclogenesis—a storm strengthening very quickly. He said the latest HRRR forecast dropped the pressure to 974 millibars near Georgian Bay on Monday morning, signaling an unusually strong storm for the region.
The system, he wrote, would generate “monster waves” on the Great Lakes and could bring down trees and cause power outages. Bitter cold would then rush in behind it, triggering lake-effect snow as 2025 ended “with a bang.”
It is almost admirable that Snitil chose “cyclogenesis” instead of the even more alarming “bombogenesis.” Still, “monster waves” ensured the forecast retained some cinematic flair.
When a Millibar Becomes Bombogenesis
Bombogenesis is not merely a made-for-TV expression. It has a specific meteorological definition, and the required rate of intensification varies by latitude.
At 60 degrees latitude, a storm qualifies when its pressure falls by at least 24 millibars, or 24 hectopascals, within 24 hours. Near New York City’s latitude, the required decline is about 17.8 millibars over the same period.
A hectopascal equals 100 pascals and is numerically identical to the older millibar. Standard sea-level atmospheric pressure, for example, may be written as either 1,013 hPa or 1,013 mb.
That raises an obvious question: If the two units are equivalent, why abandon the shorter and friendlier millibar?
The millibar was first used in 1910. One millibar is one-thousandth of a bar, while a bar equals 100,000 pascals. Perhaps the poor unit simply became too old-fashioned for modern weather broadcasts.
The term also offers considerable rhyming potential—avatar, caviar, commissar and handlebar among the possibilities—yet meteorologists have so far failed to exploit it on air.
El Niño, La Niña and Convenient Explanations
El Niño and La Niña are also routinely summoned to explain unsettling weather patterns.
The National Weather Service defines El Niño as a major warming of equatorial Pacific waters that shifts normal weather patterns. Such events generally occur every three to seven years.
That window leaves plenty of room for an El Niño to be beginning, continuing or fading at almost any given moment.
La Niña is the opposite: a major cooling of equatorial Pacific waters, also associated with changes in normal weather patterns. In other words, whether Pacific temperatures rise or fall, there is a Spanish-named climate pattern ready for the forecast.
The terminology only grows denser from there. PIVA, for example, means “Positive Isothermal Vorticity Advection.” It refers to higher vorticity values being carried by thermal wind across a map of vorticity and thickness contours, implying rising motion.
In less formidable language, changes in heat help produce upward-swirling air.
Even “scattered showers” receives a strikingly precise definition. According to the National Weather Service, the term applies when showers are expected to cover 25% to 54% of a forecast area. Apparently, simply saying “about half the area” would deny the public some vital suspense.
Hail Gets the Household-Object Treatment
Hail forecasts introduce their own elaborate measurement system. In the United States, hailstones are commonly compared with familiar objects, and stones larger than one inch in diameter are classified as severe.
A quarter represents roughly one-inch hail. A half dollar corresponds to 1.25 inches, while a walnut or ping-pong ball stands for 1.5 inches. Golf balls indicate 1.75 inches, limes two inches, tennis balls 2.5 inches and baseballs 2.75 inches.
The scale continues through large apples, softballs and grapefruits before reaching computer CDs or DVDs for hailstones measuring roughly 4.75 to five inches.
The walnut-or-ping-pong-ball indecision at 1.5 inches is especially charming. So is the idea that one-inch hail crosses a bright line into “severe,” while anything just below the threshold is somehow less concerning.
The next time hail starts falling, perhaps everyone should stop, pull out a ruler and determine whether it is safe to continue walking.
Just be prepared for the television forecast to call it a rapidly intensifying, El Niño-enhanced, PIVA-driven hail emergency—confirmed, naturally, by the European Model.