[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 021229
SWODY1
SPC AC 021227

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0627 AM CST SUN JAN 02 2005

VALID 021300Z - 031200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SE FHU 65 ESE SOW
40 NNW 4CR 45 NE ALM 40 ESE ELP.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 ENE CRP 10 SW AUS
JCT P07 INK 10 NE HOB AMA ICT 55 SW IRK 20 NW CGX 20 W GRR FNT 10
WNW ERI PIT LUK UOX MLU POE 35 ESE BPT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 SSW OTH 45 W MHS
UKI 35 SE MRY 25 ESE SMX 15 SSW RAL 20 WSW CZZ.

...NO SVR TSTM AREAS FORECAST...

AMPLIFICATION OF LARGE-SCALE UPPER FLOW REGIME IS ALREADY EVIDENT IN
LATEST WATER VAPOR IMAGERY...WITH A SIGNIFICANT MID/UPPER JET STREAK
DIGGING OFF THE CENTRAL PACIFIC COAST. THIS FEATURE IS ASSOCIATED
WITH CLOSED LOW/SHORT WAVE TROUGH...EMBEDDED WITHIN SOUTHERN BRANCH
OF POLAR WESTERLIES...WHICH IS PROGGED TO CONTINUE SOUTHWARD THROUGH
THIS FORECAST PERIOD.  MODELS SUGGEST SYSTEM WILL GRADUALLY COME IN
PHASE WITH BELT OF SUBTROPICAL WESTERLIES...IN BASE OF BROADER SCALE
TROUGH...OFF THE SOUTHERN CALIFORNIA/NORTHERN BAJA COAST.

AS THIS OCCURS...A COUPLE OF SUBTROPICAL IMPULSES WILL LIFT OUT OF
THE LOWER LATITUDE PACIFIC...ONE ACROSS THE NORTHERN MEXICAN PLATEAU
AND TEXAS BIG BEND INTO THE CENTRAL U.S...THE OTHER ACROSS NORTHERN
BAJA INTO THE SOUTHERN ROCKIES.  TENDENCY SHOULD BE FOR BOTH
FEATURES TO WEAKEN IN CONFLUENT AND INCREASINGLY ANTICYCLONIC FLOW
TO THE NORTHWEST OF AN AMPLIFYING SUBTROPICAL RIDGE ACROSS THE GULF
OF MEXICO AND SOUTH CENTRAL/SOUTHEAST STATES.  HOWEVER... INFLUX OF
MID/HIGH-LEVEL MOISTURE WILL CONTRIBUTE TO PRECIPITATION POTENTIAL
THROUGH THIS PERIOD AND BEYOND.

CIRCULATION AROUND SOUTHERN/WESTERN PERIPHERY OF LARGE SURFACE RIDGE
OFF THE ATLANTIC COAST HAS ALREADY MOISTENED LOW-LEVEL ENVIRONMENT 
FROM THE SOUTH CENTRAL STATES INTO LOWER GREAT LAKES REGION...WHERE
50S/60S SURFACE DEW POINTS ARE WIDESPREAD.  PRECIPITATION IS
DEVELOPING ACROSS MUCH OF THIS REGION IN ASSOCIATION WITH BROAD
ISENTROPIC ASCENT...AND THIS SHOULD PERSIST/INCREASE TODAY AND
TONIGHT.  DESPITE INCREASINGLY MOIST AIR MASS...RELATIVELY WARM
MID-LEVEL AIR ON WESTERN/NORTHERN PERIPHERY OF SUBTROPICAL RIDGE
WILL CONTINUE TO MINIMIZE LAPSE RATES AND CAPE.  THIS WILL LIMIT
RISK FOR VIGOROUS DEEP CONVECTIVE DEVELOPMENT...BUT AT LEAST LOW
PROBABILITIES FOR WEAK THUNDERSTORM ACTIVITY WILL EXIST. 

...WRN GULF COAST/SRN PLAINS INTO MIDDLE MISSISSIPPI VALLEY...
UNCERTAINTY STILL EXISTS WITH REGARD TO SOUTHWARD ADVANCEMENT OF
SURFACE FRONTAL ZONE ASSOCIATED WITH INTRUSION OF MODIFIED ARCTIC
AIR INTO THE NORTH CENTRAL STATES.  HOWEVER...MODELS SUGGEST
STRONGER BAROCLINIC ZONE JUST ABOVE THE SURFACE /ROUGHLY AROUND 925
MB/ WILL STALL OUT ACROSS NORTH CENTRAL OKLAHOMA THROUGH SOUTH
CENTRAL MISSOURI.  THIS COULD PROVIDE A FOCUS FOR STEEPER ISENTROPIC
ASCENT AND FORCING OF INCREASINGLY MOIST PARCELS TO LEVELS OF FREE
CONVECTION...PARTICULARLY AS SOUTHERLY LOW-LEVEL FLOW INTO THIS
REGION STRENGTHENS TONIGHT.

LOW-LEVEL JET AXIS ITSELF COULD ALSO BECOME FOCUS FOR THUNDERSTORM
ACTIVITY FROM NORTHEAST TEXAS INTO ARKANSAS AS EARLY AS LATE
AFTERNOON/EARLY EVENING.  MODELS SUGGEST LARGE-SCALE ASCENT MAY
BECOME ENHANCED BY UPPER JET STREAK ROUNDING CREST OF SUBTROPICAL
RIDGE.

GIVEN CONSIDERABLE CLOUDINESS AND TENDENCY FOR RELATIVELY WARM AND
DEEPENING MOIST ADIABATIC PROFILES AT MID/UPPER LEVELS...AHEAD OF
WEAKENING SUBTROPICAL IMPULSE...PROSPECTS FOR SEVERE THUNDERSTORMS
ACROSS THE SOUTHERN PLAINS APPEAR REMOTE.  HOWEVER...ENOUGH HEATING
MAY OCCUR FROM WEST CENTRAL TEXAS INTO SOUTHWEST OKLAHOMA FOR
CORRIDOR OF STEEPER LOW-LEVEL LAPSE RATES AND MOST UNSTABLE CAPE TO
1000 J/KG BY LATE AFTERNOON.  WITH A CONCENTRATED AREA OF MID-LEVEL
FORCING LIFTING ACROSS THIS REGION TOWARD 03/00Z... INHIBITION MAY
WEAKEN SUFFICIENTLY FOR A SMALL CLUSTER OF STORMS.  ALTHOUGH A
COUPLE OF UPDRAFTS COULD BECOME FAIRLY VIGOROUS FOR A SHORT PERIOD
OF TIME...FORECAST THERMODYNAMIC PROFILES DO NOT SEEM TOO FAVORABLE
FOR LARGE HAIL.

..KERR.. 01/02/2005

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.