FXUS64 KCRP 111130 AAA
AFDCRP
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
530 AM CST FRI DEC 11 2009
.DISCUSSION...SEE UPDATED AVIATION DISCUSSION.
&&
.AVIATION...SRLY FLOW WILL CONTINUE TO PUMP GULF MOISTURE OVER THE
TOP OF A SHALLOW COOL AIRMASS WHICH IS HELD IN PLACE ACROSS THE
REGION BY A COASTAL TROUGH DEVELOPING ALONG THE COAST. THIS WILL
LEAD TO INCREASING DRIZZLE AND LIGHT RAIN WITH PRECIP BECOMING
WIDESPREAD BY AFTERNOON. CIGS WILL CONTINUE TO FALL AS THE COOL
AIRMASS BECOME MORE AND MORE SHALLOW. MVFR CIGS WILL GIVE WAY TO
IFR AND EVENTUALLY LIFR CIGS AREA WIDE THROUGH THE AFTN. VSBY WILL
DECREASE TO 1 TO 3 SM AT TIMES WHEN PRECIP OCCURS. ONCE THE LIFR
CONDITIONS DEVELOP THEY WILL PREVAIL THROUGH THE REMAINDER OF THE
NIGHT TIMING AND DEGREE OF IMPROVEMENT ON SAT WILL BE CHALLENGING
FOR 18Z TAFS.
&&
.PREV DISCUSSION... /ISSUED 420 AM CST FRI DEC 11 2009/
SHORT TERM (TODAY THROUGH SATURDAY)...A COASTAL TROUGH WILL
CONTINUE TO SHARPEN AND DEVELOP FURTHER NORTH TOWARD THE MID TEXAS
COASTAL WATERS TROUGH TONIGHT. ISENTROPIC UPGLIDE IN THE 290-300K
LAYERS WILL INCREASE TODAY WHILE CONDENSATION PRESSURE DEFICITS
DROP BELOW 1 MB. A RIGHT JET ENTRANCE REGION WILL REMAIN ACROSS
NERN MEXICO AND INTO S TX AND THIS WILL REMAIN THE ONLY
SIGNIFICANT UPPER DYNAMIC FEATURE IN PLACE THE NEXT FEW DAYS. THIS
SETS THE STAGE FOR A LIGHT OVER-RUNNING PRECIP EVENT TODAY AND
TONIGHT WITH LIGHT RAIN AND DRIZZLE SPREADING NORTH ACROSS THE
REGION. AM A LITTLE NERVOUS ABOUT THE LACK OF SIGNIFICANT RAINFALL
ON THE RADAR ATTM AND WONDERING IF MANY AREAS MAY SEE LOTS OF
TRACE OBS AND LITTLE MEASURABLE PRECIP...BUT WENT AHEAD AND KEPT
THE 70 POPS ACROSS THE COASTAL PLAINS AND ADJACENT WATERS TAPERING
BACK TO 40 POPS IN THE WEST. THE RAIN AND DRIZZLE SHOULD TAPER OFF
FROM SW TO NE OVERNIGHT AND FOLLOWED CLOSER TO THE GFS MOS
CONFINING LIKELY POPS TO THE NERN ZONES...WITH ONLY 10-20 POPS IN
PLACE FOR SAT MORNING.
TEMP FORECAST IS VERY TRICKY AS IT IS HIGHLY DEPENDENT ON TIMING
OF ONSET OF LIGHT PRECIP TODAY. IF RAIN STARTS EARLIER...HIGHS
WILL STAY IN THE 40S AREA WIDE. IF IT HOLDS OFF UNTIL AFTN...HIGHS
COULD REACH THE 50S AREAWIDE. FOR NOW AM SHOWING TEMPS IN THE UPR
40S TO LOWER 50S (HIGHEST COASTAL AREAS) WHICH IS CLOSER TO A
CONSENSUS OF RAW MODEL OUTPUT AND IS BELOW MOS FORECASTS IN MOST
AREAS. LOWS TONIGHT WILL ONLY DROP A DEGREE OR TWO (IF AT ALL) GIVEN
WAA PATTERN ALOFT. HIGHS SAT ARE VERY TRICKY AS THE NAM KEEPS THE
COLD AIRMASS TRAPPED BELOW A BLANKET OF CLOUD COVER DESPITE THE
ISENTROPIC UPGLIDE ENDING WHILE THE GFS WARMS THING UP
DRAMATICALLY. GENERALLY SPLIT THE DIFFERENCE BETWEEN THE COOLER
NAM AND WARM GFS MOS WHICH IS NEAR 10 DEGREES IN SOME CASES.
MINOR FLOODING OF AREA BEACHES WILL REMAIN POSSIBLE DURING HIGH
TIDE THE NEXT FEW DAYS AS STRONG NE FLOW PILES WATER ALONG THE
COASTAL BEND. LOCAL RULES OF THUMB INDICATE WATER WILL INCREASE TO
AROUND 1 1/2 FEET ABOVE PREDICTED LEVELS AND ARE ALREADY AROUND 1
FOOT ABOVE RIGHT NOW. THIS MAY ALLOW WATER LEVELS JUST ABOVE 2
FEET MSL DURING THE NEXT FEW HIGHS TIDES WHICH WILL PUSH WATER UP
TO THE DUNES IN SOME AREAS.
MARINE...DEVELOPING COASTAL TROUGH IS LEADING TO STRONG NE FLOW
ACROSS THE MARINE AREAS. WILL CONTINUE THE SCA FOR ALL BUT THE BAY
ZONES THROUGH SAT MORNING AND BAYS WILL LIKELY EXPERIENCE WINDS
JUST BELOW SCA LEVELS. SEAS ARE FORECAST TO REACH 11 FEET DURING
THE PEAK OF THE EVENT. WINDS WILL TURN OFFSHORE AND DECREASE ON
SAT AS THE TROUGH LIFTS E-NE AWAY FROM THE REGION.
LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)...MAIN WEATHER IMPACT FOR
SATURDAY NIGHT INTO SUNDAY MORNING WILL BE THE POTENTIAL FOR FOG
DEVELOPMENT. MODELS CONTINUE TO INDICATE AMPLE MOISTURE AT THE
SURFACE WITH LIGHT WINDS AND DRYING ALOFT WITH WESTERLY WINDS. KEPT
MENTION OF FOG IN THE FORECAST FOR SATURDAY NIGHT AS DENSE FOG MAY BE A
CONCERN. SUNDAY INTO MONDAY TEMPERATURES WARM INTO THE 70S ACROSS
MUCH OF THE REGION AS FEWER CLOUDS WILL BE IN PLACE AND ONSHORE FLOW
BRIEFLY RETURNS. DIFFERENCES CONTINUE IN THE MEDIUM RANGE MODELS
WITH RESPECT TO THE NEXT FRONT TO IMPACT THE REGION BY TUESDAY. GFS
CONTINUES WITH A FRONTAL PASSAGE EARLY TUESDAY MORNING WHILE THE
ECMWF IS SLIGHTLY SLOWER. WILL CONTINUE TO LEAN TOWARD THE GFS
SOLUTION AND SHOW PRECIPITATION ASSOCIATED WITH THE FRONTAL PASSAGE.
HOWEVER...ECMWF CONTINUES TO CUT OFF THE UPPER LEVEL LOW OVER THE
REGION AND HOLDS ONTO CLOUDS AND PRECIPITATION THROUGH WEDNESDAY.
AGAIN...WILL GO CLOSER TO THE GFS WITH BEST CHANCE FOR RAIN TO BE
OVER THE NORTHEAST AND COASTAL REGIONS BEFORE ENDING TUESDAY EVENING.
TEMPERATURES COOL BACK TO NEAR SEASONAL VALUES THROUGH THE EXTENDED
IN WAKE OF THE COLD FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 51 48 57 47 72 / 70 40 10 10 10
VICTORIA 49 46 57 45 72 / 70 70 20 10 10
LAREDO 49 47 61 49 75 / 40 30 10 10 10
ALICE 49 46 58 46 74 / 60 40 10 10 10
ROCKPORT 52 49 57 47 70 / 70 60 20 10 10
COTULLA 48 46 60 46 75 / 40 40 10 10 10
KINGSVILLE 51 47 58 47 73 / 70 40 10 10 10
NAVY CORPUS 53 50 58 49 70 / 70 40 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST SATURDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT
20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP
CHANNEL OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL NOON CST SATURDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
&&
$$
MG/88...SHORT TERM
MG/88...LONG TERM
