SPC Severe Thunderstorm Database (ONETOR,FHAIL,FWIND) Format

Blank spaces are assumed to be missing data

Distributions are from ONETOR through 1995

Column Da ta Range Comments - ***[Distributions are counts of records
NOT counts of tornadoes]{.underline}***

1 (A) Year 1950-2001 Four digits (to be 2000 compliant)

2 (B) Num 1-232 Number of tornado in state in given year.

3 (C) State 1-99 FIPS Number of State (1-Alabama, 2-Alaska, 4-Arizona,
5-Arkansas, 6-California, 8-Colorado, 9-Connecticut, 10-Delaware,
11-District of Columbia, 12-Florida, 13-Georgia, 15-Hawaii, 16-Idaho,
17-Illinois, 18-Indiana, 19-Iowa, 20-Kansas, 21-Kentucky, 22-Louisiana,
23-Maine, 24-Maryland, 25-Massachusetts, 26-Michigan, 27-Minnesota,
28-Mississippi, 29-Missouri, 30-Montana, 31-Nebraska, 32-Nevada, 33-New
Hampshire, 34-New Jersey, 35-New Mexico, 36-New York, 37-North Carolina,
38-North Dakota, 39-Ohio, 40-Oklahoma, 41-Oregon, 42-Pennsylvania,
44-Rhode Island, 45-South Carolina, 46-South Dakota, 47-Tennessee,
48-Texas, 49-Utah, 50-Vermont, 51-Virginia, 53-Washington, 54-West
Virginia, 55-Wisconsin, 56-Wyoming, 97 (98 in 1999) -Virgin Islands,
98-Virgin Islands, 99-Porto Rico) \-- For multi state tornadoes, the
"1\" record gives the state of initial touchdown

4 (D) Month 1-12 Number of Month.

5 (E) Day 1-31 Number of Day.

6 (F) Date MM/DD/YY Paradox Coded Date.

7 (G) Time 0.00-23.98 Decimal Format - 24 Hour Clock - Central Standard
Time \... (6:15 pm CST=18.25 ).

8 (H) Zone 0-9 Time Zone (0=?, 1-EST, 2=EDT, 3=CST, 4=CDT, 5=MST, 6=MDT,
7=PST, 8=PDT, 9=GMT) -- [They All should be 3 (CST)]{.underline} --
During 1950-1997, the distribution was: 0-9; 1-1,617; 2-52; 3-33,255;
4-84; 5-838; 6-28; 7-107; 8-15; 9-2). We are checking these and the
associated times against "Storm Data." The data set will be "corrected"
when the check is finished.

9 (I) Tor. No. \-\-- A count of tornadoes during the year. For 1998 on
these numbers agree with the number assigned to the tornado by OM.

10 (J) Type 1-7 Type of Event (1-Tornado, 4-Waterspout moving ashore,
5-Tornado moving over large body of water,6-hail greater than 3/4\" in
diameter,7-winds greater than 50 kts or damaging wind ). 4 and 5 last
used in 1979. During 1950-1997, the distribution was: 1-35,832; 4-143;
5-32.

11 (K) Rmks 0-5 Tornado Event Remarks (0-none, 1-with large hail, 2-with
heavy rain, 3-with large hail and heavy rain, 4 no rain or hail, 5-?).
Rarely been from 1983 on. During 1950-1997, the distribution was:
0-31,186; 1-975; 2-2012; 3-982; 4-851; 5-1.

12 (L) No-Sts 1-3 Number of states traversed by the tornado. During
1950-1997, the distribution was: 1-35269; 2=717; 3=21. This is blank for
non-tornado entries. Note this is NOT a count of tornadoes, it is a
count of records.

13 (M) State-Tor 1-9 A flag if 1 that this is a unique state
entry\...the number of tornadoes in a state is a count of the 1 entries
(Note if a tornado leaves a state and re-enters it, there are two 1
entries in this column.

14 (N) Segno 1,2,-9 A flag indicating the nature of the record . This is
blank for non-tornadoes. During 1950-1997, the distribution was:
1-35,435; 2-484, -9-88)

1 designates a record is for a tornadoes entire path. (each tornado has
1 and only 1 record). A count of 1 records is a count of tornadoes.

2 designates of state information on a tornado that effects more than 1
state. If a tornado touches 2 states, it has two 2 records; 3 states it
has three 2 cards (if a tornado leaves and renters a state, it has two 2
records for that state, and one 2 record for the in between state. On 21
Nov. 1992 a tornado touched down in Kentucky crossed the Ohio River into
Indiana, and re-crossed the river going back into Kentucky).

-9 indicates a continuation record listing additional counties affected
by the tornado. A -9 record does not have latitudes, longitudes,
lengths, widths, fatalities, or injuries listed.

15 (O) Stlat The latitude of touchdown (tornado type 1 record, wind,
hail) or of entry point into state (tornado type 2 record). Decimal
format (90.50 = 90^o^30\"). Not on tornado -9 records.

16 (P) Stlon The longitude of touchdown (tornado type 1 record, wind
hail) or of entry point into state (tornado type 2 record). Decimal
format (90.50 = 90^o^30\"). Not on tornado -9 records.

17 (Q) Splat The latitude of lift-off (type 1 record) or of exit point
into state (type 2 record), only given if point is differentiable from
the (stlat,stlon) point. Decimal format (90.50 = 90^o^30\"). Not on 9
records. Blank on hail and wind records.

18 (R) Splon The longitude of lift-off (type 1 record) or of exit point
into state (type 2 record), only given if point is differentiable from
the (stlat,stlon) point. Decimal format (90.50 = 90^o^30\"). Not on 9
records. Blank on hail and wind records.

19 (S) Lgth 0-2347 Length of tornado track if known in tenths of statute
miles (146 = 14.6 miles). Since this accounts for nonlinear tracks so
the result might not be the same as the great circle distance from
touchdown to lift-off points. Not given for 9 records. The minimum
length is assumed to be 0.1 mi (ie =1). A width is computed for each
"segment" (state) that a tornado effects. Blank on hail and wind
records.

20 (T) Ongd 0-9 Percent of tornado path on the ground in tens of per
cent (I..E., 5=50%) and 0 denoting 100%. This was an attempt to account
for the damage area of "skipping" tornadoes. Not given for 9 records.
During 1950-1997, the distribution was: 0-31,026; 1-306; 2-295; 3-325;
4-189, 5-1,335; 6-232; 7-271; 8-378; 9-318. Rarely used after 1983.
Blank on hail and wind records.

21 (U) Area \-\-- Tornado path area in square miles. Blank on hail and
wind records.

22 (V) F\*AREA \-\-- Path area in square miles multiplied by the
F-scale. Blank on hail and wind records.

23 (W) Rot 0,1,2,3,6 An indicator for sense of tornado rotation
(1-counterclockwise; 2-clockwise; 3-?; 6-?; blank if unknown). During
1950-1997, the distribution was: 0-35,584; 1-1,015; 2-54; 3-5; 6-1. Not
given on -9 records. Not used since 1986 Blank on hail and wind records.

24 (X) Width 0-999 Mean tornado path width (if known) in tens of feet
(528 = 5280 feet = 1 mile). The mean width along the entire track is
reported. If a multi state event, it should be the same in all 2
records. Not given on -9 records. The minimum width is assumed to be 30
feet (ie = 3). A width is computed for each "segment" (state) that a
tornado effects. Blank on hail and wind records.

25 (Y) Fatal 0-116 Fatalities. A breakdown by state is given in 2
records. Not given on -9 records.

26 (Z) Inj 0-1740 Injuries. A breakdown by state is given in 2 records.
Not given for 9 records.

27 (AA) Damage 0-9 For 1995 and before this is a categorization of
tornado damage by dollar amount (0 or blank-unknown; 1\<\$50; 2-\$50 to
\$500; 3-\$500 to \$5,000; 4=\$5,000 to \$50,000; 5-\$50,000-\$500,000;
6-\$500,000 to \$5,000,000; 7-\$5,000,000 to \$50,000,000;
8-\$50,000,000 to \$500,000,000; 9\>\$5000,000,000). Not given for -9
records. During 1950-1995, the distribution was: 0-10,351; 1-1,593;
2-1,619; 3-5,159; 4-8,868; 5-6,087; 6-1,835; 7-373; 8-36; 9-0.

Starting with 1996 this is tornado property damage in

millions of dollars.

28 (AB) FIPS Number of first county (or equivalent) hit by event. Not
given on 1 records of multi state tornadoes.

29 (AC) FIPS Number of second county (or equivalent) hit by event. Not
given on 1 records of multi state tornadoes.

30 (AD) FIPS Number of third county (or equivalent) hit by event. Not
given on 1 records of multi state tornadoes.

31 (AE) For tornadoes FIPS Number of fourth county (or equivalent) hit
by tornado. Not given on 1 records of multi state tornadoes.

For Hail, this field contains Hail Size in hundredths of

inches.

For winds, this field contains Maximum Gust in knots.

32 (AF) F -9, 0 to 5 Fujita's F-scale. This is a damage classification.
Wind estimates associated with damage are crude at best. The original
reference is Fujita, T.T., 1971; "Proposed Characterization of Tornadoes
and Hurricanes by Area and Intensity," Satellite & Mesometeorology
Research Project, The University of Chicago, 40pp. A -9 indicates that
no estimate of F-Scale is available. All records (1,2,-9) on a given
tornado should have the same value. During 1950-1997, the distribution
was: -9-1,864; 0-11,783; 1-12,700, 2-7,088; 3-1,953;, 4-544;, 5-75 (Note
these are records not tornadoes). Blank on hail and wind records.

32 (AG) Pl -9, 0 to 5 Pl is a categorization of tornado path length. The
formula is: Pl = 2\*log(L) + 1 where L is length in miles. Reference
Fujita, T.T. and A.D.Pearson, 1973; "Results of FPP Classification of
1971 and 1972 Tornadoes" Preprints, American Meteorological Society
Conference on Severe Local Storms, 142-145. Pl MAX MIN -1 0.1 \-\-\-- 0
0.9 0.2 1 3.1 1.0 2 9.9 3.2 3 31.610.0 4 99.931.7 5 316.2 100.0 All
records on a given tornado have the same value. A -9 indicates that no
estimate of Pl-Scale is available (The value of length was arbitrarly
set at the minimum). Blank on hail and wind records.

33 (AH) Pw -9, 0 to 5 Pw is a categorization for path width. The formula
is: Pw = 2\*log(W) + 5 where W is the mean width, This should be
recalculated from column 24 (mean width). Reference Fujita, T.T. and
A.D.Pearson, 1973; "Results of FPP Classification of 1971 and 1972
Tornadoes" Preprints, American Meteorological Society Conference on
Severe Local Storms, 142-145.

> Pw MAX MIN 0 10 ---

1 160 52

2 525 170

3 1660 530

4 5270 1670

5 16690 5280

> A -9 indicates that no estimate of Pw-Scale is available. (The value
> of Width was arbitrarily set at the minimum) All records (1,2,-9) on a
> given tornado have the same value. Blank on hail and wind records.

34 (AI) Garbage number or character that serves as a record end. Has no
meaning.