** N.A. Monsoon Experiment Options **


** DEFINITIONS **

[CPR]  = Combined probability (Prob_Field_1 x Prob_Field_2 x ... x 
         Prob_Field_N)
[MAX]  = Maximum from any member at each grid point
[MD]   = Median
[MDXN] = Median value contoured.  The dashed red line is the union of 
         all members at the lowest contour value plotted (i.e., where 
	 at least one of the 16 members exceeds the value of the first 
	 median contour).  The dashed blue line is the intersection of
	 all members at the lowest contour value plotted (i.e., where 
	 all 16 members exceed the value value of the first median 
	 contour).
[MIN]  = Minimum from any member at each grid point
[MN]   = Mean
[MNSD] = Mean and Standard Deviation
[PM]   = Probability Matched Mean Value
[PR]   = Probability (percentage of members meeting/exceeding some 
         condition)
[SP]   = Spaghetti
[TEXT] = Text product of the NAME zone averaged precipitation

** SPECIAL NORTH AMERICAN MONSOON EXPERIMENT (NAME) SHORT-RANGE
   ENSEMBLE PRODUCTS FROM THE STORM PREDICTION CENTER **

A small sample of short-range ensemble products are provided for 
evaluation during the NAME field program.  The SPC calibrated 
forecasts of the probability of a thunderstorm are downscaled to
a 4 km grid and recalibrated with lightning information on the
same 4 km grid.  A similar technique is used to take the PQPFs
from the NCEP/SPC short-range ensemble and downscale/calibrate 
the forecast to a 4 km grid.  

These results are provided for scientific purposes commensurate with
the mission of the SPC and its appliation of short-range ensembles in
the prediction of severe weather.  These products should be considered
highly developmental and non-operational.   
	   
** SPECIFIC INFORMATION ON AVAILABLE FIELDS **

[PR]Thunderstorm ->Probability of a thunderstorm for the 3-hr period
                   ending at the forecast time.  The probabilities 
		   are based on the SPC SREF calibrated thunderstorm
		   forecast on a 40 km grid, but recalibrated to a 
		   4 km grid using surface elevation and recent 
		   lightning observations.  
[CPR]Organized Severe Thunderstorm ->The combined (or joint) probability
                                     of a severe thunderstorm.  The
				     predictors are the probability of
				     a thunderstorm (on the 4 km grid)
				     X probability DCAPE >= 500 J/kg X 
				     probability MUCAPE >= 500 J/kg X
				     probability deep layer shear >= 20 
				     kts.  This is an uncalibrated 
				     product and only meant to delineate
				     areas where CAPE, DCAPE, shear, and
				     thunderstorm potential are favorable
				     for organized thunderstorms
				     with potentially damaging winds.				  
[PR]24-hr Total Pcpn >= 0.01" ->Probability total precipiation exceeds
                                0.01" for the 24-hr period ending at
				the forecast time.  (Therefore, this
				product is only available at F24 to
				F63.)
[PR]24-hr Total Pcpn >= 0.25" ->As above but PQPF >= 0.25"
[PR]24-hr Total Pcpn >= 0.50" ->As above but PQPF >= 0.50"
[PR]24-hr Total Pcpn >= 1.00" ->As above but PQPF >= 1.00"
[PR]24-hr Total Pcpn >= 2.00" ->As above but PQPF >= 2.00"
[TEXT]24-hr Zone Ave QPFs ->NAME zone averaged QPF for the 24-hr
                            period ENDING at the forecast hour
			    selected (e.g., using the 09 UTC SREF, 
			    the "F24" forecast represents the first
			    24 hours of the SREF forecast period
			    from 09 UTC to 09 UTC).  The areal 
			    averaged QPF is determined from the 
			    downscaled PQPFs on the 4 km grid 
			    in the Tier 1 NAME region.  Average 
			    values are calculated by summing 
			    the probabilistic forecasts at the
			    various thresholds on the 4 km grid
			    within each of the nine zones, and then
			    dividing by the number of grid points
			    within the zone. The resulting areal
			    average thus represents the most likely 
			    (zone averaged) QPF predicted by the 
			    SREF. 
Terrain Map ->Surface elevation of the SPC SREF NAME domain (meters)

All SREF information presented herein is for guidance purposes 
only and should not be confused with official SPC operational 
forecasts.  Links to official SPC operational products are found 
at the bottom of every menu.

Many of the SREF products were developed for testing the utility 
of SREF analysis in the prediction of SPC mission critical items, 
including: thunderstorms and severe thunderstorms, large scale 
critical fire weather conditions, and mesoscale areas of hazardous 
winter weather. In order to accomplish this goal and test new and 
unqiue methods of SREF application in an operational environment, 
many fields not produced in the NCEP postprocessor were calculated 
locally for SPC purposes.



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