Monday, April 16, 2018

Nearly Another Tax Day Storm

Strong cold fronts and associated mayhem are pretty common in northern Utah around Tax Day.  The all-time classic is the 15 April 2002 Tax Day Storm, which produced the 2nd lowest sea level pressure observed in Utah since record keeping began in 1892, temperature falls of 7˚C in 10 seconds and 19˚C in 2 hours, and wind gusts of more than 60 knots.  Others include the 2015 Tax Day Storm, described by Judy Fahys in this KUER article

We would have another today, if not for an oddity in the calendar.  Chances are you've noticed the nuking southerly flow, and the NWS has wind advisories or warning's up for much of weatern and southern Utah.

The view from my office is starting to look dusty.  What a shame it will be if we put down a layer of brown goo on the wonderful white snow we have right now. 

The culprit in this case is a strong front and surface trough to our west.  These features are forecast by the HRRR to extend across far NW Utah at 2000 UTC (1400 MDT) this afternoon. 

Frontal passage is expected late this afternoon (the HRRR pegs it at around 5 PM MDT for the northern Salt Lake Valley).  Sadly, the surface frontal passage will be a dry one, although precipitation will develop in it's wake tonight.  It's a quick hitter event, but don't be surprised if you wake up to some white stuff on cold surfaces tomorrow depending on the elevation of your home.  As usual, monitor official forecasts. 

Now, getting back to Tax Day, what is so special about it?  Basically, its a noteworthy day in the heart of the peak season for strong cold-frontal passages in the Intermountain West. 

Source: Shafer and Steenburgh (2008)
Today's frontal passage almost qualifies as a Tax Day Storm.  Normally, April 15 is Tax Day, but April 15 fell on a Sunday.  While that should shift Tax Day to today, Washington D.C. observes Emancipation Day on April 16, which pushes Tax Day to April 17, tomorrow.

However, if you want to call this a Tax Day Storm, I'm good with it.

No comments:

Post a Comment