[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 220559
SWODY1
SPC AC 220557

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1157 PM CST SUN JAN 21 2007

VALID 221200Z - 231200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
NRN AND SRN STREAM UPPER TROUGHS -- INITIALLY PHASED AS A
POSITIVELY-TILTED FEATURE EXTENDING FROM ERN CANADA/THE UPPER GREAT
LAKES SWWD INTO THE DESERT SW -- ARE FORECAST TO SEPARATE INTO TWO
DISTINCT FEATURES WITH TIME.  THE NRN STREAM TROUGH IS FORECAST TO
MOVE EWD/SEWD ACROSS ERN CANADA/THE NERN CONUS...WHILE THE SRN
STREAM CLOSED LOW MOVES SLOWLY SEWD ACROSS THE SWRN U.S./NWRN
MEXICO.  A LIGHTNING STRIKE OR TWO WILL BE POSSIBLE N OF THE
U.S./MEXICO BORDER...WHILE THE POTENTIAL FOR A FEW STRIKES WILL ALSO
EXIST ACROSS SERN GA/NRN AND CENTRAL FL AHEAD OF WEAK COLD FRONT.

...SERN GA/NRN AND CENTRAL FL...
WEAK INSTABILITY IS FORECAST TO DEVELOP AHEAD OF SURFACE
FRONT...WHERE SEASONABLY-MOIST BOUNDARY LAYER /DEWPOINTS IN THE 60S/
WILL EXIST.  DEGREE OF INSTABILITY...AND CONVERGENCE ALONG FRONT
SHOULD BE SUFFICIENT FOR WEAK CONVECTIVE DEVELOPMENT DURING THE
AFTERNOON.  HOWEVER...THUNDER THREAT SHOULD REMAIN QUITE LIMITED DUE
TO WEAK INSTABILITY -- AND THE FACT THAT THE EQUILIBRIUM LEVEL OF
MOST UPDRAFTS SHOULD REMAIN BELOW THE -20 C LEVEL -- IN THIS CASE
FORECAST TO BE AROUND 25000 FT AGL.

...SERN AZ/SWRN NM/FAR W TX...
STEEP LAPSE RATES/COLD MID-LEVEL TEMPERATURES ACCOMPANYING THE UPPER
TROUGH WILL EXTEND ACROSS PARTS OF AZ/NM/FAR W TX AND INTO NWRN
MEXICO THIS PERIOD...POSSIBLY RESULTING IN VERY WEAK CAPE ACROSS
PORTIONS OF THIS AREA.  A LIGHTNING STRIKE OR TWO MAY OCCUR N OF THE
U.S./MEXICO BORDER FROM SERN AZ EWD TO FAR W TX INVOF UPPER
LOW...THOUGH GREATER THREAT SHOULD REMAIN S OF THE BORDER THROUGH
THE PERIOD.

..GOSS.. 01/22/2007