NCEP HPC and SPC,
EMC SREF (MODEL) DERIVED
WINTER WEATHER IMPACT GRAPHICS
Prob %
AREA AK CONUS
FHR
Loop 03 06 09 12
15 18 21 24 27
30 33 36 39 42
45 48 51 54 57
60 63 66 69 72
75 78 81 84 87
Probability of Significant Impacts
SFC VIS
RATE (Intensity)
DURATION
1/2 Mile
1"/hr
12 hr
1/4 Mile
2"/hr
24 hr
1/8 Mile
3"/hr
48 hr

Probability for Other Impacts
Accum on Roads
ZR>=.01"
Bliz Crit

Exceedance of NWS WSW Criteria
12h Snow
ZR
24h Snow

Mean Event Total Accumulations
Combined S/IP
ZR
S/IP
ZR
ABOUT THESE GRAPHICS
SREF HOME PAGE
HPC External Winter Wx Site
HPC WWD Model Diagnostics
Experimental Natl Rad Loop
ZOOM - Zoom button, then repeat LEFT click
UNZOOM - Repeat RIGHT click or Reset button
PAN - Drag left button while zoomed

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HPC WWD COMMENTS FORM