Ticker for October 25, 2001

                
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October 25, 2001   October 25, 2001   October 25, 2001   October 25, 2001


Frost / Freeze Update

Temperatures at a handful of Mesonet stations in northern and western
Oklahoma dipped below the freezing mark this morning.  The following
map shows the duration of sub-freezing temps and the minimum
temperature achieved (red dots indicate some missing data):




Medicine Park: Inversion Poker

Medicine Park has a long history of "inversion poking" and this morning
was no different.  Take a look at the 9:15 am air temperature field:



That's Medicine Park providing all the red color near Lawton.  Its
temperature was as much as 15 degrees greater than those of its
nearest neighbors.  That's because the site, which sits within viewu
of Mount Scott, has sufficient elevation and/or topography effect to
"poke" through a shallow surface inversion into warmer air aloft.
This morning's sounding from Norman shows exactly that: a very shallow
(and substantial) surface inversion:



Even though Medicine Park and Hobart are just a county apart, their
overnight conditions were quite different:




These meteograms show overnight temps falling into the upper 30s at
Hobart, while critters near Medicine Park enjoyed relatively balmy 50s.

This phenomenon occurs quite often over the course of a year.  Medicine
Park is the network's most prolific inversion poker, but we've also
observed it at other sites, such as Cheyenne, Newkirk, Ada and Minco.
What do all these sites have in common?  They are situated among
relative high ground compared to neighboring sites.