Easterly Winds

As Napoleon learned all to well, all bad things come from the east.  A walk on campus this morning is a bit more challenging that it has been in a few weeks given the cooler weather and the blustery winds.  Here are a few peak gusts since 11 PM last night from around the area:

Farmington/I-15: 68 mph
Mouth Parleys Canyon: 62 mph
Centerville: 54 mph
Bountiful Bench: 54 mph
University of Utah: 53 mph
Hill Field: 52 mph
Fruit Heights: 51 mph

Pretty much everyone is getting in on the action in this one. [Addendum @ 11:08 AM: Everyone along the east bench of the Salt Lake Valley and the northern Wasatch Front - JS].

The time series from the Mouth of Parley's is quite interesting.  Winds have been steadily out of the east since late Saturday.  Although it is not unusual to have strong easterly flow at this location at night and in the morning, note that the easterlies persisted through the day yesterday, and then reached their maximum strength this morning with a peak gust of 62 mph (right hand side of the graph).

 Note how the speed goes down and the wind direction becomes erratic from around noon to 1600 yesterday.  The surface heating and associated turbulent mixing acts to weaken the strength of the downslope flow in these events.  As a result, they often reach their maximum intensity overnight and in the early morning and slacken during the day.  

More information on this phenomenon can be found by examining our previous posts on downslope winds.