4 ms·

Here's the bit, buried towards the end: The 19/12z NAEFS is indicating IVT values 19.1 sigmas above the mean; it should be noted that it is using a dataset th

Here's the bit, buried towards the end: The 19/12z NAEFS is indicating IVT values 19.1 sigmas above the mean; it should be noted that it is using a dataset that does not include the rash of tropical cyclones that impacted the Southwest in the 1970's, so this value is likely a bit too high. Even assuming a non-standard distribution and standard deviations half as large, this is extreme. There is a very real potential for 3" amounts in an hour in this environment should sufficient instability be present. Even if instability was completely eroded, 0.5" an hour totals would be possible; heavy rain appears inevitable. The 00z Canadian Regional shows local amounts of towards 10", which would be exceeding rare for the region from a tropical cyclone, potentially unique for Nevada. The 100 year ARI is forecast to be exceeded. Some locations within this arid region are slated to get 1-2 years worth of rain in one day. If a 7"+ maximum materialized over Mount Charleston Sunday into early Monday, it would challenge Nevada's 24 hour rainfall record, set in 2004.

pard68 3y ago
What's wild to me is that 1-3" of rain / hour is about our norm for any given storm (southern MO, where evey cloud is a microburst). Really helps put into perspective how little rain Cali is used to.
- dpe82 3y ago
  At least that part of California. It's a gigantic state and some areas see fairly significant seasonal rain. This storm, however, will impact a region that includes the Mojave Desert - the dryest place in North America.
  - anon84873628 3y ago
    IIRC, The excellent book Dreamt Land says 2/3 of California's precipitation falls in the northern 1/3 of the state. But it's the southern part with the ideal climate for agriculture. Hence the largest water movement system in history.
luma 3y ago
One interesting thing I learned while in Las Vegas during a major rain storm, a lot of the buildings leak like a sieve. Word was that heavy rain happens so rarely that leaks are rare to present themselves and thus hard to discover and hard to troubleshoot.
- jstarfish 3y ago
  Same with your windshield wipers. You use them so infrequently, you don't notice the rubber disintegrated until the next time you need them.

pard68 3y ago

What's wild to me is that 1-3" of rain / hour is about our norm for any given storm (southern MO, where evey cloud is a microburst). Really helps put into perspective how little rain Cali is used to.

dpe82 3y ago
At least that part of California. It's a gigantic state and some areas see fairly significant seasonal rain. This storm, however, will impact a region that includes the Mojave Desert - the dryest place in North America.
- anon84873628 3y ago
  IIRC, The excellent book Dreamt Land says 2/3 of California's precipitation falls in the northern 1/3 of the state. But it's the southern part with the ideal climate for agriculture. Hence the largest water movement system in history.

luma 3y ago

One interesting thing I learned while in Las Vegas during a major rain storm, a lot of the buildings leak like a sieve. Word was that heavy rain happens so rarely that leaks are rare to present themselves and thus hard to discover and hard to troubleshoot.

jstarfish 3y ago
Same with your windshield wipers. You use them so infrequently, you don't notice the rubber disintegrated until the next time you need them.