Hot desert rain

California Hit With Hottest Rain in Recorded History

With much of the U.S. continuing to suffer under the worst drought conditions in half-a-century, any rainy weather system at all might seem a refreshing sight -- but evidently, sometimes a T-storm can feel a lot like a tea-storm.

Treehugger,

15 August, 2012

According to Weather Underground, the city of Needles, California, recently experienced what is believed to be the hottest rainfall on record. On Monday, not long after hitting a daytime high of 118°F (the hottest it's ever been there, by the way), a thunderstorm rolled through, dropping precipitation over the Mojave Desert town that reached a scorching 115°F.

"Monday's rain at 115° in Needles sets a new world record for the hottest rain in world history," writes weather expert Dr. Jeff Masters.



But that wasn't the only record set that day. The rain fell with conditions at just 11 percent humidity, "the lowest humidity rain has ever occurred at anywhere on Earth in recorded history."



Due to the low humidity, however, only a scattering of the super-hot droplets reached the ground before evaporating, sparing unsuspecting residents from the full brunt of an oddly shower-like rain shower.



Dr. Master explains the science behind the scalding rain:

It is exceedingly rare to get rain when the temperature rises above 100°F, since those kind of temperatures usually require a high pressure system with sinking air that discourages rainfall. Monday's rain in Needles was due to a flow of moisture coming from the south caused by the Southwest U.S. monsoon, a seasonal influx of moisture caused by the difference in temperature between the hot desert and the cooler ocean areas surrounding Mexico to the south.

Prior to Needles' record-setting rain, the hottest on record occurred in Saudi Arabia, reaching temperatures of 109°F. And, what might seem a mere arbitration, may in fact be a growing trend; to date, the top three hottest rainfalls on record have occurred within the last two years.