BEHAVIOR PATTERNS OF NEW ENGLAND HAILSTORMS 
Ol a a a a) ea To T T T ==) 
mox 
7 L =e re 
Z y mox 
Oe NS 
eee mo My) max 
mox _-- 
| ue 45 a/m> 
median 
“median 
5 medion .—_——" 45x10"! 
LOG Zmox mecton 
all 45x10? 
3p STORM CLASS 
HAIL REPEATER 
~--—) HAIL <20 MINUTES 
2 
1 4 1 =i 1 n 1 n 4 
“150 -120 -390 -60 -30 ° 30 60 90 120 150 
TIME AFTER FIRST HAIL — minutes 
Fic. 9—The trends of median and maximum log Zmax for the two groups 
of hailstorms, related to time before or after first hail 
CONVECTIVE INDEX: Hyngy (K ft) X LOG Zmox 
TORNADO STORM MAX 
TIME OF MOST DESTRUCTIVE 
TORNADO 
400} 
STORM IDENTIFYING NUMBER 
INDEX 
HAILSTORM 
300 “a 
4300 
HIGH Z aa 
QUARTILE r 
z F 
RAIN TY, PL / 
x / 
De 
y 7 REPEATERS 
MEDIAN eZ \ 
A } x 
fi / \ 
I aN 
200 oy ; Re 200 
“i a ; = 
Low / Peat 
POUAnTICE ff ‘MEDIAN OF STORMS WITH 
we a HAIL < 20 MINUTES. 
/ 
’ 
10 1 L L 1 n 1 n 100 
-30 60 =30 ° 30 60 90 120 150 
TIME AFTER FIRST HAIL (MINUTES) 
Fie. 10—Median convective index 
trends in hailstorms with less than 20 
minutes of hail, hail repeater storms, and tornado-producing hailstorms; 
the convective index maximum and 
time of most destructive tornado are 
shown separately for each tornado storm; all times are before or after first 
hail; at left, medians and quartiles of a large number of rain-thunderstorms 
and hailstorms are plotted, independent of timing 
decay of convective index for the median hail re- 
peater. 
The position of the leading edge of hail was de- 
termined relative to the low-altitude echo core 
in 25 cases where both the timing and location 
of the hail occurrence were considered accurate 
within limits of one minute and one mile. The po- 
sition of the low-altitude echo core was interpo- 
lated from the available measurements, generally 
taken two to five times during an hour. The rela- 
tive hail locations, plotted in Figure 11, seem to 
have quite a scatter, but closer examination shows 
that half of all hail and three-fourths of hail 
larger than ¥-inch falls within three miles of the 
echo core. 
There were many hail occurrences for which 
