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> Steve, > > Thanks for your reply. Clearly I misunderstood that Max Temp is a forecast > Max Temp and not simply the maximum temperature at the time of a sounding. > Also, I misinterpreted how NSHARP calculated the convective temperature. I > didn't dig deep enough into the code and comments and should have done so > before contacting you. > > Evan > Evan, No problems. Nsharp is one of those add on" programs so its documentation etc isn't as well integrated with the rest of the package. Steve Chiswell Unidata User Support > -----Original Message----- > From: Unidata GEMPAK Support [mailto:address@hidden] > Sent: Thursday, September 27, 2007 2:51 PM > To: address@hidden > Cc: address@hidden > Subject: [GEMPAK #NAT-847496]: GEMPAK - NARR Model Sounding Max Temp / Conv. > Temp Bug > > > Institution: Plymouth State University > > Package Version: NSHARP 4.0 > > Operating System: Linux > > Hardware Information: Dell Server > > Inquiry: Hi, > > > > Just pointing out a possible bug. When generating NARR model proximity > > (lat/lon) soundings in the latest version of NSHARP, it appears that Max > > Temp and Conv Temp values are flipped. > > > > Max Temp is actually Conv Temp and vice versa. The values are correct but > > flipped. > > > > Attached is a postscript example taken from 20030708_0900 at 43.64, -70.63. > > > > Evan Lowery > > > > -------- > > Plymouth State University > > Applied Meteorology M.S. Program > > > > > > > > Evan, > > The Max Temp being computed is: > /* Calculates a maximum temperature forecast based on */ > /* depth of mixing level and low level temperatures. */ > > Looking at your postscript file, a miximg down of the air at the top > opf the inversion dry adiabatically would result graphically of 26X which is > close to the Max Temp of 84F shown in your plot. > > > The Convective temperature is: > /* Computes convective temperature, assuming no change in */ > /* moisture profile. Parcels are iteratively lifted until */ > /* only (mincinh) j/kg are left as a cap. The first guess */ > /* is the observed surface temperature. */ > > The mincinh specified for this output is "-50 j/kg". Note that the dashed line > shown in the plot is the default most unstable level, and not surface which > can be specified using the PARCEL button on the page. Again, frlm ispection > of your plot, > the value of 20C would be pretty close to the moist adiabat of most of the > atmosphere brought > down to the surface, so that is ~68F. The value shown of 65F in your plot is > that which > contains a cap of -50 j/kg, so again, based on what is shown in your plot, > the values > seem to match. > > My inperpretation is that with a convective temperature lower than the > theoretical max temp, > you would expect cloudcover to begin after convetctive mixing begins which > would > therefore be a counteractive force to the expected max tempBut, were you > expecting something > different?. > > Steve Chiswell > Unidata User Support > > Ticket Details > =================== > Ticket ID: NAT-847496 > Department: Support GEMPAK > Priority: Normal > Status: Closed > > > Ticket Details =================== Ticket ID: NAT-847496 Department: Support GEMPAK Priority: Normal Status: Closed