Monday, February 5, 2024

Complicated Week Ahead

I suspect the skiing yesterday was very good.  I had to sit it out due to a balky back.  Hope you were more fortunate. 

The big weather story today is really from SoCal where some big rainfall numbers are coming in from the LA Basin and environs.  Below are 24-hour totals as of this morning with seven sites in the Santa Monica Mountains and Beverly Hills coming in with more than 10 inches of rain.  

The analysis below shows the situation at 0000 UTC 5 Feb (5 PM MST Sunday) with a deep cyclone just off the central California coast and strong integrated vapor transport directed toward the Santa Monica and San Gabriel Mountains.  It was a great recipe for heavy orographic precipitation development.  

Utah will be seeing bits and pieces of that storm as the trough moves through the western US.  As I looked at things this morning, I had no idea how to summarize the next few days.  The system is so broken up over the western interior that it's hard to summarize the timing and intensity of when things will happen with any confidence.  Perhaps the simplest description is to say we will see warm and windy conditions through tomorrow then a gradual transition to cooler weather (but not cold) midweek, with periods of precipitation at times.

The GFS forecast below provides one perspective. Note the forecast temperatures in the mid 20s at Alta-Collins with wet-bulb zero levels between about 6000 and 7000 feet through Tuesday night when temperatures begin to decline.  The GFS produces some precipitation today, late Tuesday, and then late Wednesday and Thursday totaling a bit over 1.2" of water and 17" of snow, which will be fairly high density today and tomorrow before transitioning to lower density on Wednesday.  

I don't have a lot of confidence in the timing and amounts for the bits and pieces as they come through. Timing and intensity are hard to anticipate with confidence, but the periods of snow will add up as the week goes on perhaps to 2 to 3" of water at the end of the work week.  The mean of the downscaled NAEFS is a bit over 3" with most members in the 2-4" range.  

Keep an eye on forecasts and expect updates as this is an evolving situation with a lot of complexity.  

1 comment:

  1. Any more continuity between the models as the storm approaches? Are the models converging? Thank you!