Tempertures
increased dramatically in the upper elevations of the Wasatch Mountains last night. At the base of Alta, temperatures climbed from -2F just after sunset yesterday to 22F at 7 am this morning.
The temperature increase is associated with an upper-level front that is passing through Utah from the north and is associated with both warm advection and subsidence. Note the strong warming between 1800 UTC (1100 MST) yesterday ant 1200 UTC (0500 MST) today.
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| NAM Analysis Valid 1800 UTC 2 Feb 2011 |
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| 6-h NAM Forecast Valid 1200 UTC 1 Feb 2011 |
This morning's sounding very clearly shows the upper-level front, evident as the strong inversion and wind shear between 850 and 700 mb. Thus marks the end of this cold wave in the mountains, but the valley still needs to recover.
There are some very interesting soundings this morning in the region of the upper-level cold pool. For example Albuquerque (ABQ), near the center of the arctic air mass looks like a true arctic sounding, with no obvious tropopause. I noticed that SLC is much colder above 350 mb then ABQ. Also check out Del Rio (DRT), Brownsville (BRO) and Monterrey, Mexico (MAN). And Tuscon is near its February record minimum (currently at 18F).
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