Severe Weather Verification
SVR (severe thunderstorm warnings): The number of severe thunderstorm warnings issued.
TOR (tornado warnings): The number of tornado warnings issued.
TOTAL (total of severe and tornado warnings): The total number of severe thunderstorm and tornado warnings combined.
FFW (flash flood warnings): The number of flash flood warnings.
WARN (warnings): The number of warnings issued.
VERIF (verification): The number of warnings that verified.
EVENTS (events): Total number of actual severe weather events.
UNWARN (unwarned): The number of unwarned events.
WATCH (watches): The number of watches that were in effect before warnings were issued.

FAR (false alarm ratio): The percentage of warnings where the particular weather event did not occur.
POD (probability of detection): The percentage of events that were warned for and the conditions occured.
CSI (critical success index): The number of warned events divided by the sum of the total number of events and the number of the unverified counties.
LT (lead time): The average lead time before the first reported instance of the particular event.

SVR/TOR Warnings

YEAR
SVR
TOR
TOTAL
EVENTS
FAR
POD
CSI
LT
1994 133 36 169 166 .503 .620 .381 12.1
1995 125 9 134 104 .590 .606 .324 13.2
1996 89 5 94 76 .436 .868 .519 18.2
1997 224 36 260 204 .388 .882 .565 21.9
1998 330 52 382 386 .343 .904 .614 27.1
1999 125 16 141 131 .362 .924 .606 23.6
2000 240 14 254 260 .276 .919 .681 22.4
2001 184 14 198 216 .228 .931 .730 19.1
2002 170 28 198 214 .192 .879 .727 17.4
2003 118 8 126 135 .254 .859 .665 15.4
2004 165 27 192 190 .375 .847 .562 19.8




Flash Flood

YEAR
FFW
EVENTS
FAR
POD
CSI
LT
1997 14 8 .357 1.000 .643 18.8
1998 48 32 0 1.000 1.000 31.3
1999 38 18 .447 .778 .477 54.0
2000 76 45 .092 1.000 .908 48.9
2001 15 7 .553 1.000 .467 41.4
2002 20 15 .250 .813 .639 49.3
2003 4 2 .500 1.000 .500 0
2004 82 49 .098 .980 .886 70.0




Tornadoes

YEAR WARN EVENTS UNWARN FAR POD CSI LT
1994
1995 9 6 4 .778 .333 .154 4.3
1996 5 2 1 .800 .500 .167 11.5
1997 36 7 2 .861 .714 .132 5.9
1998 52 9 3 .885 .667 .109 5.6
1999 16 5 1 .750 .800 .235 22.4
2000 14 6 3 .786 .500 .176 9.2
2001 14 9 2 .357 .778 .543 18.1
2002 28 9 3 .750 .667 .222 7.8
2003 8 1 0 .875 1.000 .125 18
2004 27 20 7 .593 .650 .334 13.2




Winter Weather

YEAR
WARN
VERIF
EVENTS
PRECEDED
BY WATCH
FAR
POD
CSI
LT
1998-99
55
41
54
35
.255
.759
.603
8h/7m
1999-00
61
21
29
8
.656
.733
.306
9h/10m
2000-01
185
142
148
107
.232
.959
.743
11h/33m
2001-02
69
33
34
18
.522
.971
.471
14h/56m
2002-03
73
34
44
10
.534
.773
.410
8h/37m
2003-04
90
49
55
46
.456
.891
.510
22h/27m
2004-05
105
98
112
91
.007
.880
.820
15h/42m




High Wind

YEAR
WARN
VERIF
EVENTS
WATCH
FAR
POD
CSI
LT
1998-99
0
0
0
0
1999-00
10
5
5
0
.500
1.000
.500
1 hr
2000-01
26
25
25
0
.038
1.000
.962
12 hr/15 min
2001-02
0
0
0
0
2002-03
0
0
0
0
2003-04
8
4
8
0
15 min
2004-05
12
10
11
0
.170
.910
.770
7 hrs/42 min

Last Updated 6/14/05 - tjs

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