WMOD00290 ‎(3)‎

• Title: Automated Objective Analysis and Prediction of Mesoscale Convective Systems
• Prepared By: David A. Matthews, Leon Osborne
• Date: 6/6/1983
• Weather Modification - Doc Type: Report

SOO 1""1

'"1
::J

700 ltel

900 ltel

'C'-c-<' .

.. ~#~~~

7;.a)6/C18 UUJ TO 791tWW09 OJII)
;/ TOTAL rJEl..."5

#15'
~

ItQ.O

lOLl

101.~Ot<i. 101.i 101.2

100.1

101.0

:t'

11i:~~ II'II'lU. 1.1 "...1df7ij~RlifnT'""DtiVVllP I' GRIOOCO RNAlTSIS fOR 19060900

b::~~_. >!:'TlCAL"''''''''''''''
'., ____ ~ 7; TOT"_ 'lEe'"
at.. -- - ';f'!!!1 300 1P181
.,,~,.. "" "" "" '''', l1!!1
." ,/ /.............-..........--~ 010 ICDI

~: ~ 500 1~1
::I~;/~~
~,~~ \~~"~~ ~_~{ 700 I~'
! J k~-/J;:bp~/f.' _ ...
,,~-~$
~ :: '"
~ U
IIli: 0.0

I~.O

7Q.<:0f,/OB 1800 TO 19106/09 0300
,.; TOTAL fiELDS
"#!!i
"ff

lOLl

lOltCING.I01.t

100.1

101.2

101.0

Figure 4: Divergence (x10-5/s) at 0000 GMT, June 9, 1979 (a), and kine-
matic vertical motion (lLbar/s) field (b). Note the blocking of
flow by the thunderstorms in the northwest section of the net-
work and strong vertical motion in the center from 700 to 300 mb.

T1WlS

~); i;;~.;~

~ -. -. ..~ _. :. .. _. JIJI

~""::'~':'~~~

-.1 -... -.. 4i P

soo 1""1
II "11iI -46.3 IftI
'f "Ill 2S.2'"

700 II'l8J
lit "IH .28. I I'RX
Y"11oI 14.1 fib

900 if'ej
II "1101 .".3 tIlJ
Y"11f 6.7 tIlJ

J.D
...
Z "D
i :::
D.'
..,

79106/08 1800 TO 7I/CIIICII OSIII II.
TOTAL n c.o .
.I~I
I tJiJlJo" R. .31. .... fUiII . - 7
,t. CD:T. cr ...... .43 "IJI'I:.. 2.D

Figure 5: Three-dimensional wind vector fields
at 2100 GMT, June 9, 1979, showing
30-min horizontal and vertical
transport. Vertical scale shows
vector transport in pressure coordi-
nates above and below the observation
surface. Rainfall observed in a
.rain gage network is shown in the
bottom level.

By 1800 GMT, a distinct area of diver-
gence moved over the network at 200 to 300 mb,
producing divergence of 18 x 1O-5/s at 300 mb.
The band-pass objective analysis clearly shows
a distinct anticyclonic upper-level mesoscale
circulation and relatively weak convergence
-5 x 10-5/s from 500 to 900 mb. Rapid devel-
opment of strong vertical motion fields with
lifting of -30 to -70 ILbar/s occurred from
1800 to 2100 GMT. The macroscale, mesosc.ale
and total field analyses, shown in Fig. 3,

790W821

44.1 fW; .3.
49.4 fW; 3$.

OJ
II:

11.5 LIlWS -12.
25.S IWS Ie.

5.S IW; .11.
22.] IW$ Ii.

Radar echo
locot;0II5

-+-
/

Figure 6:

Conceptual airflow model and radar
echo structure observed at 2100 GMT,
June 8, 1979. Sma 11 numbers in flow
vectors indicate Qe (K), while
larger numbers identify automatic
ce 11 tracked radar echoes. Bottom
level shows surface location of
echoes.

demonstrate the type of information available
in the band-pass analysis. Note the smooth
macroscale field and distinct mesoscale eddy
circulations which produce the total field
convergence (Fig. 4.a) and moderate vertical
motion patterns (Fig. 4.b) at 1800 GMT. The
three-dimensional vector analysis at 1800 GMT
showed a distinct surface of 1 ifting from 700
to 300 mb levels which rapidly evolved info a
strong region of organized lifting from 900 to
300 mb at 2100 GMT, as show~ in ~ig. 5. Winds

34