FXUS64 KMOB 151033
AFDMOB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOBILE AL
430 AM CST TUE DEC 15 2009
.SHORT TERM (TODAY AND TONIGHT)...AHEAD OF A FRONT CURRENTLY SOUTH
OF A KMEI TO KHEZ LINE...GOOD ISENTROPIC UPGLIDE SHOWERS WITH
EMBEDDED THUNDERSTORMS WILL BE THE NAME OF THE GAME TODAY. WITH THE
HELP OF SOME JET DYNAMICS...FROM A JET STREAK APPROACHING FROM OVER
SOUTHERN TX AND ANOTHER OVER THE TENN RIVER VALLEY...HEAVY RAINS ARE
LIKELY OVER THE AREA. WITH FFW VALUES VERY LOW...MORE FLASH FLOODING
IS LIKELY. WHEN COMBINED WITH THE AREAL FLOODING OVER SOME AREAS OF
THE FA...THE FA WILL LIKELY SEE EVEN MORE FLOODING PROBLEMS
TODAY...TRANSFERRING TO THE ALREADY SWOLLEN RIVERS THROUGH THE REST
OF THE SHORT TERM INTO THE EXTENDED. MOST THE DETAILS ARE FROM THE
GFS...THOUGH HAVE BUMPED THE POPS UP THIS EVENING...TAKING A HINT
FROM THE NAM(WHICH TAKEN FACE VALUE IS OVER-BLOWN). /16
WEDNESDAY THROUGH THURSDAY NIGHT...DRY CONDITIONS FOLLOW FOR
WEDNESDAY AND WEDNESDAY NIGHT WHILE A WELL DEFINED SHORTWAVE TROF
ADVANCES ACROSS THE SOUTHERN PLAINS. A SURFACE LOW DEVELOPS OVER
THE NORTHWESTERN GULF IN RESPONSE TO THE SHORTWAVE AND TRACKS
EASTWARD THROUGH THURSDAY...PASSING SOUTH OF THE FORECAST AREA
THURSDAY NIGHT. THE GFS HAS COME INTO AGREEMENT WITH THE ECMWF ON
THIS EVOLUTION...WHICH HAS HAD THIS FEATURE FOR SEVERAL DAYS. A
LARGE SURFACE RIDGE REMAINS OVER THE EASTERN STATES THROUGH THURSDAY
NIGHT SETTING THE STAGE FOR ENHANCED OVERRUNNING FLOW. LIGHT TO
MODERATE ISENTROPIC UPGLIDE INITIALLY HIGHER IN THE ATMOSPHERE ON
THURSDAY...300-305K...IS FOLLOWED BY STRONGER UPGLIDE FROM 290-305K
THURSDAY NIGHT AS THE SURFACE LOW PASSES SOUTH OF THE AREA. MEX
POPS LOOK REASONABLE FOR BOTH THURSDAY AND THURSDAY NIGHT AS THE
MORE CONSISTENT ECMWF IS WRINGING OUT EVEN MORE PRECIP. /29
&&
.LONG TERM (FRIDAY THROUGH MONDAY)...THE GULF LOW INITIALLY SOUTH OF
THE FORECAST AREA FRIDAY MORNING CONTINUES EASTWARD ACROSS THE
FLORIDA PENINSULA THROUGH FRIDAY NIGHT THEN NORTHWARD UP THE COAST
OF THE SOUTHEAST U.S. THROUGH SATURDAY NIGHT. EXCELLENT AGREEMENT
AMONG THE GFS/ECMWF EARLY ON DEGRADES SOMEWHAT DURING THIS PERIOD
BUT IS SUFFICIENT FOR GOOD CONFIDENCE IN MEX POPS WHICH START WITH
GOOD CHANCE ON FRIDAY TAPERING OFF TO SLIGHT CHANCE SATURDAY...THEN
DRY SATURDAY NIGHT. DRY AND COLDER CONDITIONS FOLLOW FOR SUNDAY
INTO MONDAY AS THE GFS/ECMWF/GEM ALL MOVE A STRONG UPPER TROF ACROSS
THE EASTERN STATES WITH DEEP LAYER NORTHWESTERLY FLOW USHERING
COLDER AIR INTO THE REGION. ALTHOUGH THERE IS INCREASING
VARIABILITY AMONG THE GFS ENSEMBLE MEMBERS SUNDAY INTO MONDAY...THE
GFS ENSEMBLE MEANS ARE VERY CLOSE TO THE OPERATIONAL GFS AND WITH
GOOD AGREEMENT AMONG THE GFS/ECMWF/GEM ON THE SYNOPTIC PATTERN...AM
ACCEPTING THE COLDER MEX TEMPERATURES DURING THE PERIOD. /29
&&
.HYDROLOGY...MANY OF OUR AREA RIVERS ARE AT OR NEAR BANKFULL DUE TO
THE HEAVY RAINFALL OVER THE PAST SEVERAL DAYS. UNFORTUNATELY MORE
HEAVY RAIN IS EXPECTED FOR TODAY. WIDESPREAD INUNDATION FLOODING
WILL PERSIST ESPECIALLY NEAR AREA RIVERS AND CREEKS THAT ARE AT
BANKFULL. THIS IS A VERY SERIOUS SITUATION. RIVERS AND CREEKS CAN
RISE QUICKLY. DO NOT DRIVE THROUGH FLOODED AREAS...ESPECIALLY AT
NIGHT.
A FEW RIVER FLOOD FORECASTS WERE UPGRADED FROM MINOR TO MODERATE
SEVERITY ON MONDAY EVENING TO ACCOUNT FOR THE ADDITIONAL RAINFALL.
ONE SUCH RIVER WAS THE CONECUH RIVER AT RIVER FALLS. THE RIVER IS
EXPECTED TO RISE TO NEAR 45 FEET BY TUESDAY EVENING. THIS WOULD
CAUSE FLOODING OF U.S. HIGHWAY 84 AND WOULD BE NEAR A HISTORICAL
CREST. THE FIFTH HIGHEST HISTORICAL CREST WAS 45.90 FEET IN 1913.
BAYOU SARA HAS CONTINUED TO RISE OVER NIGHT AND IS CURRENTLY AT 6
FEET WHICH IS WELL INTO THE MODERATE STAGE. BAYOU SARA IS AFFECTED
BY RUNOFF AND TIDAL FLUCTUATIONS. BAYOU SARA SHOULD SLOWLY BEGIN TO
FALL LATER THIS MORNING. OTHER AREA RIVERS THAT ARE EXPECTING TO
REACH MODERATE FLOOD ARE...BIG ESCAMBIA AT FLOMATON...MURDER CREEK
AT BREWTON...LEAF RIVER AT MCLAIN...AND CHICKASAWHAY RIVER AT
LEAKESVILLE.
THE PASCAGOULA RIVER IS EXPECTED TO RISE TO 24.5 FEET TONIGHT WHICH
WILL CAUSE FLOODING OF STREETS AND PORTIONS OF THE OLD BUSINESS
SECTION OF MERRILL WOULD BECOME FLOODED. MINOR RIVER FLOODING IS ALSO
EXPECTED ON ALABAMA RIVER AT MILLERS FERRY...ALABAMA RIVER AT THE
CLAIBORNE DAM...PERDIDO RIVER AT BARRINEAU PARK...STYX RIVER AT
ELSANOR...TOMBIGBEE RIVER AT COFFEEVILLE...TOMBIGBEE AT
LEROY...CONECUH RIVER AT BREWTON...ESCAMBIA RIVER AT CENTURY...THE
BLACKWATER RIVER AT BAKER...AND THE SHOAL RIVER AT CRESTVIEW.
SEVERAL OTHER AREA RIVERS THAT ARE IN ACTION STAGE THIS MORNING ARE
THE MOBILE RIVER AT THE BARRY STEAM PLANT...TALLAHALA CREEK AT
RUNNELSTOWN...FISH RIVER NEAR SILVERHILL...YELLOW RIVER NEAR
MILLIGAN...AND THE BIG COLDWATER CREEK AT MILTON.
FOR MORE SPECIFIC INFORMATION ON RIVER FLOODING...PLEASE REFER TO
THE LATEST HYDROLOGIC STATEMENTS...RIVER FLOOD WARNINGS...AND RIVER
FLOOD STATEMENTS ISSUED BY THE NATIONAL WEATHER SERVICE IN MOBILE.
04/KC
&&
.MARINE...WIDESPREAD RAIN WITH SCATTERED THUNDERSTORMS WILL CREATE
LOCALLY REDUCED VISIBILITIES TODAY. A SURFACE FRONT WILL START
ACROSS THE LAND AREA THIS MORNING...THEN ACROSS AL/NW FL COASTAL
WATERS THIS AFTERNOON INTO THIS EVENING.
AFTER THE FRONTAL PASSAGE...STRONG OFFSHORE FLOW WILL MOVE IN LATE
THIS AFTERNOON. FLOW WILL EASE SOMEWHAT WEDNESDAY INTO WEDNESDAY
NIGHT...BUT WITH A SURFACE SYSTEM PASSING SOUTH OF THE AREA LATE
THURSDAY INTO FRIDAY...THE STRONG OFFSHORE FLOW WILL RETURN
THURSDAY...LASTING THROUGH MOST OF THE WEEKEND. /16
&&
.AVIATION (12Z ISSUANCE)...PERIODS OF RAIN WITH SOME THUNDERSTORMS
WILL KEEP LOW CIGS/VISBYS THIS MORNING INTO THIS AFTERNOON AHEAD OF
A FRONT WILL MOVE ACROSS THE AREA BEGINNING THIS MORNING. SKIES WILL
CLEAR TONIGHT...BUT WINDS WILL BE ON THE INCREASE THIS AFTERNOON
INTO TONIGHT. /16
&&
.FIRE...VERY MOIST CONDITIONS TODAY ARE FOLLOWED BY DRY CONDITIONS
WEDNESDAY IN THE WAKE OF A COLD FRONT. AFTERNOON RELATIVE
HUMIDITIES WILL DROP ONLY INTO THE SEVENTIES THIS AFTERNOON THEN
DROP INTO THE UPPER THIRTIES ON WEDNESDAY. RELATIVE HUMIDITIES
REMAIN ABOVE CRITICAL LEVELS AND INCREASE SOMEWHAT ON THURSDAY AS
GULF MOISTURE BEGINS TO RETURN TO THE REGION AS A LOW PRESSURE
SYSTEM ADVANCES FROM THE NORTHWESTERN GULF. /29
&&
.PRELIMINARY POINT TEMPS/POPS...
MOBILE 65 44 59 38 / 100 50 05 10
PENSACOLA 68 47 61 43 / 100 50 05 10
DESTIN 70 54 63 46 / 100 50 05 10
EVERGREEN 64 41 58 36 / 100 20 05 05
WAYNESBORO 62 39 55 32 / 100 10 00 05
CAMDEN 63 40 56 34 / 100 10 05 05
CRESTVIEW 67 46 62 39 / 100 50 05 05
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...FLASH FLOOD WATCH UNTIL 6 PM TUESDAY FOR THE FOLLOWING ZONES:
BUTLER...CHOCTAW...CLARKE...CONECUH...COVINGTON...
CRENSHAW...ESCAMBIA...LOWER BALDWIN...LOWER MOBILE...
MONROE...UPPER BALDWIN...UPPER MOBILE...WASHINGTON...AND
WILCOX.
FL...FLASH FLOOD WATCH UNTIL 6 PM TUESDAY FOR THE FOLLOWING ZONES:
COASTAL ESCAMBIA...COASTAL OKALOOSA...COASTAL SANTA ROSA...
INLAND ESCAMBIA...INLAND OKALOOSA...AND INLAND SANTA ROSA.
MS...FLASH FLOOD WATCH UNTIL 6 PM TUESDAY FOR THE FOLLOWING ZONES:
GEORGE...GREENE...PERRY...STONE...AND WAYNE.
GM...SMALL CRAFT ADVISORY FROM 6 PM TUESDAY TO 6 PM FRIDAY FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM DESTIN TO PENSACOLA FL
OUT 20 NM...COASTAL WATERS FROM PENSACOLA FL TO PASCAGOULA
MS OUT 20 NM...MOBILE BAY...WATERS FROM DESTIN TO PENSACOLA
FL FROM 20 TO 60 NM...AND WATERS FROM PENSACOLA FL TO
PASCAGOULA MS FROM 20 TO 60 NM.
&&
$$
