** Severe Weather 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



** SPECIFIC INFORMATION ON AVAILABLE FIELDS **

[MDXN]:CravenBrooks_SigSvr ->Craven-Brooks significant severe is
                             the product of MUCAPE x 0-6 KM shear.  
			     Median contours begin at 10000 m^3/s^3
			     with the union (dashed red) and 
                             intersection (dashed blue) at 10000
			     m^3/s^3 shown.
[MDXN]:SigTor_Param ->Signficant tornado parameter.  Median contours 
                      begin at 1 with the union (dashed red) 
		      and intersection (dashed blue) at 1 shown.
[MDXN]:Supercell_Comp_Param ->Signficant tornado parameter.  Median 
                             contours begin at 1 with the union (dashed 
			     red) and intersection (dashed blue) at 1 
			     shown.
[MNSD]:CravenBrooks_SigSvr ->Mean and standard deviation of Craven-
                             Brooks Significant Severe (MUCAPE X 6 KM
			     shear)
[MNSD]:SigTor_Param ->Mean and standard deviation of significant 
                      tornado parameter
[MN]:Supercell_Composite(Eff_Shear)
[CPR]:ConPcpn_1000MUCAPE_30EffShr ->Product of the probabilities: 
                                    Convective precip >= .01"; MUCAPE
				    >= 1000 J/kg; Effective Shear >=
				    30 kts
[CPR]:ConPcpn_1000MUCAPE_40EffShr ->As above but MUCAPE >= 1000 J/kg
                                    and effective shear >= 40 kts
[CPR]:ConPcpn_2000MUCAPE_30EffShr ->As above but MUCAPE >= 2000 J/kg
                                    and effective shear >= 30 kts
[CPR]:ConPcpn_2000MUCAPE_40EffShr ->As above but MUCAPE >= 2000 J/kg
                                    and effective shear >= 40 kts
[CPR]:ConPcpn_3000MUCAPE_20EffShr ->As above but MUCAPE >= 3000 J/kg
                                    and effective shear >= 20 kts
[CPR]:ConPcpn_500MUCAPE_30EffShr ->As above but MUCAPE >= 500 J/kg
                                    and effective shear >= 30 kts
[CPR]:ConPcpn_500MUCAPE_40EffShr ->As above but MUCAPE >= 500 J/kg
                                    and effective shear >= 40 kts
[PR]:CravenBrooks_SigSvr>=20000 ->Probability Craven-Brooks significant
                                  severe (MUCAPE X 0-6 KM shear) >=
				  20000 m^3/s^3
[PR]:CravenBrooks_SigSvr>=40000 ->As above but for 40000 m^3/s^3
[PR]:SigTor_Param>=1 ->Probability significant tornado parameter >=
                       1
[PR]:SigTor_Param>=3 ->As above but for significant tornado parameter
                       >= 3
[PR]:Supercell_Comp_Param>=1 ->Probability supercell composite 
                               parameter >= 1
[PR]:Supercell_Comp_Param>=3 ->As above but for supercell composite
                               parameter >= 3 
[SP]:CravenBrooks_SigSvr_10000 ->Spaghetti plot of Craven-Brooks 
                                 significant severe parameter at 
				 10000 m^3/s^3
[SP]:CravenBrooks_SigSvr_20000 ->As above but for Craven-Brooks 
                                 index of 20000 m^3/s^3
[SP]:CravenBrooks_SigSvr_40000 ->As above but for Craven-Brooks 
                                 index of 40000 m^3/s^3
[SP]:SigTor_Param_1 ->Spaghetti plot of significant tornado index
                      of 1
[SP]:Supercell_Comp_Param_1 ->Spaghetti plot supercell composite
                              parameter of 1


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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