957 
FXUS64 KBMX 311950
AFDBHM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM, AL
245 PM CDT FRI MAY 31 2002

FORECAST QUANDARIES...POPS...TEMPS.

CURRENT REGIONAL SFC OBS AND SATELLITE DATA SHOWING DEVELOPMENT OF
SCT CU FIELDS...WITH RADAR MOSAIC IMAGERY SHOWING SHWRS NEAR I-59-
AL/GA LINE. LATEST MSAS/HAND SFC ANALYZES DEPICTING SFC RIDGE APEX
NEAR MSL...TEMPS MID 80S...DEWPOINTS MID 60S...WITH VRBL WIND CONDITIONS.
UPPER AIR ANALYZES SHOWING UPPER LEVEL LOW OFF CNTRL LA COAST...WITH
RIDGING BUILDING IN FROM FOUR CORNERS HIGH PRESSURE SYSTEM.  
 
12Z FRI REGIONAL MODEL INITIALIZATIONS AND PROGGED EVOLUTIONS THRU
12Z MON IN GOOD GENERAL AGREEMENT...ESPECIALLY IN LOWER LEVELS.
HOWEVER...AS POINTED OUT BY LATEST MODEL DIAGNOSTIC DISCUSSION...MODELS
DIFFER ON 500MB CLOSED LOW PLACEMENT THRU PERIOD. NCEP PREFERS A BLENDED
MODEL SOLUTION...WITH AVN PLACEMENT MOST CONSISTENT. LIKE THE RUN-TO RUN
CONSISTENCY OF THE AVN MYSELF. THUS...WILL LEAN TOWARD A BLENDED MODEL
SOLUTION WITH ANY DISCREPANCIES SETTLED BY LEANING TOWARD AVN.

UPPER LEVEL LOW EXPECTED BY ALL MODELS TO RETROGRADE SWD E OF BRO BY
SAT MORNING...WITH UPPER LEVEL RIDGE INFLUENCE FROM NM CONTINUING
TO BUILD INTO STATE....ESPECIALLY N. RIDGE AXIS WILL SHIFT INTO CNTRL U.S.
...AND INTO SE U.S. BY 12 MON. LOW WILL EITHER REMAIN QUASI-STATIONARY
OR MOVE SLIGHTLY E INTO CNTRL GULF BY 12Z MON. ALTHOUGH RIDGING DYNAMICS
DEVELOPING...POSITION OF LOW WILL STILL PROVIDE A SWLY MOISTURE FETCH
ACROSS A LEAST CNTRL AND S ZONES THRU MON MORNING. SFC RIDGING PATTERN
WILL ALSO CONTINUE TO PERSIST THRU THIS TIME PERIOD. THUS...CONTINUE
TO BELIEVE PTCLDY SKIES MOST APPROPRIATE SKY CONDITION.  LOOK FOR
BEST SCT CU FIELD DEVELOPMENT TO BE DIURNALLY BASED. DO NOT BELIEVE
IT WILL BE AS WIDESPREAD AS LAST NIGHT...HOWEVER WILL MENTION PATCHY
FOG LATE ALL AREAS TONIGHT.  

MAIN FORECAST QUANDARY CENTERS AROUND POPS. WITH ISOLATED CONVECTION
PRESENTLY ACROSS NE ZONES...WILL USE EVENING WORDING IN ZONES. WILL ALSO
INTRODUCE ISOLATED POPS E ZONES NEAR GA BORDER...AS CONVECTION DEVELOPING
ACROSS W CNTRL GA. OTHER LOCATIONS WILL LEAVE DRY. WITH PW/S ACROSS REGION
THRU MON AOB 1.4 INCHES...AND MULTIPLE INSTABILITY INDICES...ALONG
WITH CAPES AOB 3000 J/KG DURING THE AFTERNOON HOURS ON SAT AND SUN...
CAN NOT RULE OUT ISOLATED CONVECTION...DESPITE RIDGING INFLUENCES.
SPC EVEN PLACING AL IN GENERAL TS CRITERIA FOR SAT. WILL CONTINUE
ISOLATED AFTERNOON AND EARLY EVENING SHWRS/TSTMS WORDING ALL ZONES...
EXCEPT S ZONES WHERE PROXIMITY TO RICHER MOISTURE POOL MAY RESULT IN
SCT SHWR/TSTM ACTIVITY.      

REST OF WEEK...NEXT FRONTAL PASSAGE WILL OCCUR ON THU...WITH HIGH
PRESSURE BUILDING OUT OF THE CNTRL U.S AND INTO THE E U.S. BY FRI EVENING.
THIS WILL PROVIDE FOR DRY CONDITIONS ACROSS CWA ON FRI. FROM MON MORNING
THRU THU...WILL CONTINUE WITH PTCLDY SKY CONDITION WORDING AND SCT 
AFTERNOON/EVENING SHWRS/TSTMS. UPPER LEVEL LOW WILL CONTINUE MOVING
SLOWLY NEWD...AND INTO S ATLANTIC BY 00Z FRI...WITH UPPER LEVEL
RIDGE DEVELOPMENT THAT WOULD HAMPER CONVECTIVE DEVELOPMENT NOT
ANTICIPATED UNTIL FRI.

TEMPS...WILL GO WITH A MESH FORECAST OF NGM AND AVN MOS VALUES AND
SURROUNDING ZONES FORECASTS. MOS ADVERTISING ACROSS CNTRL AND S ZONES
ON SUN TEMPS IN LOWER 90S. WARMUP DEPENDENT ON LOW POSITION...AND AT
THIS TIME WILL BE A LITTLE CONSERVATIVE AND CUT BACK NUMBERS.   

THANKS FOR COORDINATION TLH

...PRELIMINARY NUMBERS...
HSV   65  88  67  89  /  20  20   0  20
BHM   66  89  68  90  /   0  20   0  20
MGM   67  90  69  91  /   0  20   0  30

.BHM...NONE.
89
JBW