Despite dire warnings of over 20 inches of rain in the New Orleans and southeast Louisiana (fig 1), Hurricane Barry fizzled out rather more quickly than anticipated after it made landfall. The Weather Channel has more details on the totals and the reasons about why it may have happened (fig 2). The aggregated six hourly totals from SYNOP observations didn’t even add up to an inch of rainfall for the whole event for New Orleans (fig 3).
There maybe “no definitive link between climate change and Storm Barry”, but that didn’t stop the BBC adding a “government health warning” to every news item they did about the storm from Matt McGrath (fig 4), warning that tropical storms in the future will be much more energetic and life threatening due to a combination of global heating and rising global sea levels. The reason that storms from now on will be more intense he explains, is because they will become more sluggish in their movement, dumping more rain in any one location. He seems to base his reasoning on how Hurricane Harvey behaved in 2017, but each tropical cyclone is different and has it idiosyncrasies, and Harvey’s was that it just happened to be very slow moving. I wonder if Barry didn’t produce as much rain as was predicted because of the NWP models not picking up the mid-level drier air from the north, or was it just failure in global heating to do it’s thing?