540
FXUS64 KBMX 130503
AFDBMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1203 AM CDT TUE AUG 13 2013
.DISCUSSION...
POST SUNSET ENHANCEMENT ONGOING IN THE SOUTHWEST RIGHT NOW. ONLY
SHORT RANGE MODEL THAT PICKED THIS UP WAS THE 22Z RUN OF THE RAPID
REFRESH MODEL. IN FACT WOULD SAY THAT IS WAS ALMOST SPOT ON WITH
THE STRONGEST STORM IN NORTHEAST SUMTER AND WEST GREENE COUNTY
ONLY MISSING IT BY 10 MINUTES. SO WHY ARE WE SEEING THE UPTICK.
WELL FROM BEST WE CAN TELL THERE WAS AN OUTFLOW MOVING
NORTHEAST...POSSIBLY A SEA BREEZE THAT MADE IT THIS FAR NORTH...
THAT MERGED INTO A LINE OF THUNDERSTORMS THAT WERE MOVING EAST.
THIS HAS CREATED AN EFFECTIVE MESO-LOW THAT IS NOW MOVING AND
SPREADING THE ACTIVITY TO THE NORTHEAST. THE RAPID REFRESH MODEL
KEEPS THE ACTIVITY GOING THROUGH 6Z AND THEN WEAKENS IT AS THE
ACTIVITY FROM THE COLD FRONT SLIDING SOUTH BEGINS TO STEAL THE
ENERGY.
THERE LIES THE OTHER PART OF THE EQUATION FOR THE FORECAST
TONIGHT. WHERE WILL BE THE BEST CHANCES FOR RAIN AHEAD OF THE
FRONT BE ACROSS CENTRAL ALABAMA AND CAN THE ACTIVITY STAY AS
NUMEROUS AS IT CURRENTLY IS. THE RAPID REFRESH MODEL KEEPS THE
ACTIVITY TOGETHER THROUGH 7Z AND THEN BEGINS TO SCATTER IT OUT
ACROSS NORTHEAST ALABAMA. HAVE UPPED POPS ACROSS THE NORTH TO
ACCOUNT FOR THIS AS WELL. UPDATES HAVE BEEN SENT AND WILL SEE WHAT
THE NEXT UPDATE FROM THE RAPID REFRESH MODEL AND MAKE ADJUSTMENTS
BY 11 PM IF NEEDED FOR THE OVERNIGHT PERIOD.
16
&&
.AVIATION...
06Z TAF DISCUSSION.
MOST OF THE CONVECTIVE ACTIVITY HAS DIMINISHED AT THIS TIME...BUT
A FEW STORMS COULD LINGER FOR A FEW MORE HOURS IN THE NORTH.
MODELS SHOW SOME WEAK ISENTROPIC LIFT SETTING UP AGAIN
OVERNIGHT...MAINLY IN THE NORTH...SO COULD SEE SOME MORE PATCHES
OF LOW CLOUDS. HAVE ONLY MENTIONED SCT MVFR CIGS AT THIS TIME DUE
TO LOW CONFIDENCE IN OVERALL COVERAGE. WILL AMEND IF COVERAGE
LOOKS TO BE GREATER THAN CURRENTLY ANTICIPATED.
NUMEROUS STORMS EXPECTED ON TUESDAY AS A FRONTAL BOUNDARY MOVES IN
FROM THE NORTH. HEAVY RAINFALL AND LIGHTNING WILL BE THE PRIMARY
THREATS. WINDS WILL GENERALLY BE OUT OF THE WEST AT LESS THAN 10
KTS...WITH SOME GUSTS POSSIBLE IN TSTORMS.
19
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$