Hail and Damaging Winds in Alabama, April 11, 2008

AREA FORECAST DISCUSSION...UPATED
NATIONAL WEATHER SERVICE MOBILE AL
1225 PM CDT FRI APR 11 2008

.UPDATE...WE HAVE DECIDED ON A FLASH FLOOD WATCH FOR TONIGHT OVER
THE EXTREME SOUTHERN HALF OF THE FCST AREA...SEE FFAMOB. THIS WATCH
IS OVER THE REGION THAT RECEIVED ANYWHERE BETWEEN 6 TO 8 INCHES OVER
A WIDESPREAD AREA LAST WEEKEND (WITH SOME LOCALLY HIGHER AMOUNTS).
WHILE RAINFALL TOTALS ASSOCIATED WITH TONIGHTS FRONTAL PASSAGE ARE
EXPECTED TO BE MUCH LESS...GENERALLY 1 TO 2 INCHES (WITH ISOLATED
TOTALS OF 2 TO 4 INCHES). MANY SMALL CREEKS AND STREAMS OVER PARTS
OF SOUTHERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE REMAIN AT OR
NEAR BANKFULL AS A RESULT OF LAST WEEKENDS RAINS...AND ANY
ADDITIONAL HEAVY RAINFALL TONIGHT COULD CAUSE THESE SMALLER RIVERS
AND CREEKS TO RISE TO NEAR OR OVER BANKFULL. SOME PONDING OF WATER
AND MINOR FLOODING OF AREA ROADWAYS WILL ALSO BE POSSIBLE DURING THE
OVERNIGHT HOURS. 12/DS

.HYDROLOGY...SEVERAL AREA RIVERS REMAIN HIGH AND SOME ARE STILL IN
ACTION STAGE. THE MAIN CONCERN FOR OUR AREA RIVERS WILL BE THE
AMOUNT OF RAINFALL EXPECTED TONIGHT AND EARLY SATURDAY. AS MENTIONED
ABOVE...WE ARE EXPECTING 1 TO 2 INCHES OF RAINFALL WITH ISOLATED
AMOUNTS OF 2 TO 4 INCHES THROUGH EARLY SATURDAY. THIS WILL PROBABLY
KEEP THE LARGER RIVERS BELOW FLOOD STAGE...BUT THE SMALLER RIVER
BASINS APPEAR TO BE THE MAIN CONCERN...ESPECIALLY OVER THOSE THAT
HAD PROBLEMS LAST WEEKEND AND EARLIER THIS WEEK. WE WILL BE
MONITORING THIS SITUATION CLOSELY AND PROVIDING UPDATES IF
NECESSARY.  04/KC

UPDATED WWA SECTION BELOW TO INCLUDE THE FLASH FLOOD WATCH.

...PREVIOUS DISCN FROM 425 AM CDT FRI APR 11 2008 FOLLOWS...

.SHORT TERM (TODAY AND TONIGHT)...DEEP LOW PRESSURE SYSTEM (989 MB)
OVER IOWA THIS MORNING IS FORECAST TO LIFT SLOWLY UP ACROSS LAKE
MICHIGAN BY LATE TONIGHT WITH A TRAILING COLD FRONT EASING INTO THE
DEEP SOUTH. AHEAD OF THE BOUNDARY...UPPER AIR TEMPERATURE PROFILES
CONTINUE TO INDICATE A THERMAL CAP AT 8 TO 10KFT. DOPPLER WEATHER
RADAR INDICATES SOME SHOWERS HERE AND THERE...BUT MID LEVEL CAP
LOOKS TO REMAIN STRONG ENOUGH AS TO PREVENT MUCH IN THE WAY OF
THUNDER THROUGH MUCH OF THE MORNING...EXCEPT THE FAR NORTHWEST ZONES
BY LATE MORNING. BY AFTERNOON...CAP SHOULD BEGIN TO ERODE ENOUGH
ALLOWING CONVECTIVE POTENTIAL ENERGY TO INCREASE UPWARDS OF 1000 TO
1500 J/KG...SUPPORTING THUNDERSTORMS MAINLY OVER THE WESTERN HALF OF
THE FORECAST AREA AS FRONT NEARS. WITH DEEP LOW WELL TO THE NORTH OF
OUR AREA...SOUTHWESTERLY LOW LEVEL JET LOOKS TO REMAIN IN THE 30 TO
40 KNOT RANGE...NOT AN OVERLY IMPRESSIVE NUMBER WHEN CONSIDERING
SEVERE WEATHER. HOWEVER...WITH DESTABILIZATION EXPECTED AND A BRIEF
WINDOW OF MARGINAL BULK SHEAR...WILL MENTION A FEW SEVERE
THUNDERSTORMS MAINLY OVER THE NORTHWEST HALF THE FORECAST AREA. WITH
BEST DYNAMICS LIFTING UP TO THE NORTH AND FLOW BECOMING
UNIDIRECTIONAL RESULTING IN A WEAKENING TREND IN SHEAR...FORECASTERS
ANTICIPATE SOME WEAKENING TO THE CONVECTIVE LINE AS IT MOVES
EASTWARD TONIGHT. IT APPEARS THE MAIN THREAT IN SEVERE THUNDERSTORMS
WILL BE DAMAGING STRAIGHT LINE WINDS WITHIN BOWING LINE SEGMENTS.

LATEST DOPPLER WEATHER RADAR WIND PROFILES SHOW 30 TO 35 KNOTS OF
WIND ABOUT 2KFT OFF THE SURFACE. WITH MIXING TODAY...EXPECT IT TO
BECOME BREEZY WITH SURFACE WINDS 15 TO 25 MPH WITH SOME HIGHER
GUSTS.

DUE TO DEEP SOUTHERLY FLOW...TEMPERATURES WARM INTO THE LOWER/MID
80S MOST AREAS. OVER THE BEACHES...WHERE SOUTHERLY FLOW COMES OFF
THE COOLER WATER...DAYTIME MAXIMUMS IN THE MID/UPPER 70S THERE.
/10

.LONG TERM (SATURDAY THROUGH NEXT FRIDAY)...THE COLD FRONT WILL BE
MAKING ITS EXIT SOUTHEASTWARD ACROSS SOUTH CENTRAL ALABAMA AND THE
WESTERN FLORIDA PANHANDLE SATURDAY MORNING...THEN A DRIER AIRMASS
WILL FILTER IN ACROSS THE REGION BEHIND THE FRONT IN THE LATE
MORNING AND AFTERNOON HOURS.  WE CONTINUE WITH LIKELY POPS THROUGH
MID MORNING SATURDAY OVER THE PANHANDLE AND OUR INTERIOR EASTERN
ZONES...BUT QUICKLY TRIM THEM DOWN TO SLIGHT CHANCE OR LESS IN THE
EAST BY MID AFTERNOON.  THE GFS AND ECMWF ARE SIMILAR IN DIGGING THE
UPPER TROUGH SIGNIFICANTLY FAR SOUTH OVER THE SOUTHEASTERN STATES
SATURDAY THROUGH SUNDAY...BRINGING WRAP AROUND CLOUDCOVER TO THE
EASTERN TWO THIRDS OF OUR AREA ON SUNDAY.  WE MIGHT EVEN SEE A FEW
SPRINKLES SUNDAY AS THE UPPER SHORTWAVE TRACKS SOUTHEAST ACROSS
ALABAMA...AND WE MENTIONED A SLIGHT CHANCE OF RAIN FOR SUNDAY FOR
THAT REASON.  OTHERWISE...THE UPPER TROUGH TRANSITIONS EAST OFF THE
EASTERN SEABOARD LATE MONDAY INTO TUESDAY WITH CLEARING SKIES
EXPECTED OVER OUR AREA STARTING MONDAY AFTERNOON.  THE GFS AND ECMWF
ARE ALSO IN FAIR AGREEMENT BRINGING SOME MUCH COOLER TEMPS TO OUR
REGION SUNDAY THROUGH TUESDAY...WITH OVERNIGHT READINGS GETTING DOWN
INTO THE 30S MOST INLAND AREAS SUNDAY NIGHT...THEN DOWN INTO THE
LOWER 30S OVER THE INLAND COUNTIES MONDAY NIGHT.  OUR FORECAST TEMPS
ARE WARMER THAN THE GFS FOR SUNDAY NIGHT GIVEN SIGNIFICANT AMOUNTS
OF MECHANICAL MIXING (DUE TO WIND) AND CLOUDCOVER...AND WE TRENDED
JUST A COUPLE DEGREES WARMER THAN THE GFS FOR MONDAY NIGHT GIVEN WE
ARE DEEP INTO THE TRANSITION SEASON AND THE GFS MAY BE A TAD BIT
COOL.  STILL...WE WILL HAVE TO WATCH OUT FOR A FROST OVER THE INLAND
AREAS BY MONDAY NIGHT.  A DEEPLY DRY AIRMASS WILL PREVAIL THROUGH
LATE NEXT WEEK...SO NO RAIN WAS PUT INTO THE FORECAST PAST THIS
WEEKEND.  /05

&&

.MARINE...A MODERATE ONSHORE FLOW CONTINUES TODAY WITH SEAS LOOKING
TO RANGE 4 TO 6 FEET ON AVERAGE. WILL HAVE CAUTIONARY WORDING IN
ZONES TODAY AS SMALLER MARINE CRAFT COULD HAVE SOME DIFFICULTY. COLD
FRONTAL PASSAGE SATURDAY MORNING BRINGS AN END TO THE THUNDERSTORMS
WITH A LIGHT TO MODERATE OFFSHORE FLOW SETTING UP. AS SURFACE HIGH
PRESSURE OVER THE NATIONS MID SECTION STRENGTHENS AND NOSES INTO THE
MARINE AREA...OFFSHORE FLOW INCREASES LATE IN THE WEEKEND. NORTHERLY
FLOW DECREASES AND SEAS START TO SUBSIDE BY TUESDAY...AS HIGH
PRESSURE TO THE NORTH WEAKENS. /10

&&

.FIRE WEATHER...ABOVE AVERAGE HUMIDITY VALUES AND STRONG SOUTHERLY
TRANSPORT WINDS WILL CONTINUE TODAY AHEAD OF AN APPROACHING COLD
FRONT.  EXPECT TO SEE A SQUALL LINE MOVE EAST ACROSS THE FORECAST
AREA LATE TODAY AND TONIGHT JUST AHEAD OF THE COLD FRONT.  THE COLD
FRONT WILL EXIT EAST OF THE AREA SATURDAY MORNING WITH NORTHWESTERLY
TRANSPORT WINDS AND A DRIER AIRMASS FILTERING IN ON SUNDAY.  DEEPLY
DRY AIRMASS WILL RESULT IN MUCH LOWER RH VALUES SUNDAY...AND WE
MAINTAIN A FIRE WEATHER WATCH FOR SUNDAY ACROSS THE WESTERN FLORIDA
PANHANDLE DUE TO THE POTENTIAL OF LONG DURATIONS OF LOW RH.  /05

&&

.PRELIMINARY POINT TEMPS/POPS...
MOBILE      81  62  73  46 /  40  70  40  10
PENSACOLA   78  62  71  48 /  30  60  60  10
DESTIN      77  65  70  52 /  20  60  60  10
EVERGREEN   83  61  70  43 /  40  70  40  10
WAYNESBORO  80  55  71  39 /  60  60  30  10
CAMDEN      82  60  71  43 /  60  70  30  10

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...FLASH FLOOD WATCH FROM 7 PM FRIDAY TO 7 AM SATURDAY FOR THE
     FOLLOWING ZONES: COVINGTON...ESCAMBIA...LOWER BALDWIN...
     LOWER MOBILE...UPPER BALDWIN...AND UPPER MOBILE.

FL...FIRE WEATHER WATCH FROM 11 AM SUNDAY TO 6 PM SUNDAY FOR THE
     FOLLOWING ZONES: COASTAL ESCAMBIA...COASTAL OKALOOSA...
     COASTAL SANTA ROSA...COASTAL WALTON...INLAND ESCAMBIA...
     INLAND OKALOOSA...AND INLAND SANTA ROSA.

     FLASH FLOOD WATCH FROM 7 PM FRIDAY TO 7 AM SATURDAY FOR THE
     FOLLOWING ZONES: COASTAL ESCAMBIA...COASTAL OKALOOSA...
     COASTAL SANTA ROSA...INLAND ESCAMBIA...INLAND OKALOOSA...
     AND INLAND SANTA ROSA.

MS...NONE.
GM...NONE.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED...
NATIONAL WEATHER SERVICE MOBILE AL
1118 AM CDT FRI APR 11 2008

ALZ051>064-FLZ001>006-GMZ630-650-655-670-675-MSZ067-075-076-078-
079-121600-
CHOCTAW-WASHINGTON-CLARKE-WILCOX-MONROE-CONECUH-BUTLER-CRENSHAW-
ESCAMBIA-COVINGTON-UPPER MOBILE-UPPER BALDWIN-LOWER MOBILE-
LOWER BALDWIN-INLAND ESCAMBIA-COASTAL ESCAMBIA-INLAND SANTA ROSA-
COASTAL SANTA ROSA-INLAND OKALOOSA-COASTAL OKALOOSA-MOBILE BAY-
COASTAL WATERS FROM PENSACOLA FL TO PASCAGOULA MS OUT 20 NM-
COASTAL WATERS FROM DESTIN TO PENSACOLA FL OUT 20 NM-
WATERS FROM PENSACOLA FL TO PASCAGOULA MS FROM 20 TO 60 NM-
WATERS FROM DESTIN TO PENSACOLA FL FROM 20 TO 60 NM-WAYNE-PERRY-
GREENE-STONE-GEORGE-
1118 AM CDT FRI APR 11 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF INLAND SOUTHEAST
MISSISSIPPI...SOUTHWEST ALABAMA...THE WESTERN FLORIDA
PANHANDLE...AND THE ADJACENT COASTAL WATERS OF ALABAMA AND NORTHWEST
FLORIDA.

.DAY ONE...THIS AFTERNOON AND OVERNIGHT.

A COLD FRONT WILL APPROACH OUR REGION DURING THE AFTERNOON HOURS.
ISOLATED THUNDERSTORMS...SOME LOCALLY SEVERE...WILL OCCUR OVER
INTERIOR SOUTHEASTERN MISSISSIPPI EARLY AND THIS WILL PROGRESS
EASTWARD INTO SOUTHWESTERN ALABAMA AS THE DAY PROGRESSES.
CURRENTLY...FORECASTERS FEEL THAT THE EVENT COULD POSSIBLY BEGIN AS
DAMAGING WIND THREAT AND END WITH YET ANOTHER HEAVY RAINFALL EVENT
THAT WOULD TAKE SHAPE FROM MID-EVENING THROUGH OVERNIGHT.  SMALL
CREEKS AND STREAMS ARE ALREADY NEAR BANKFULL OVER THE EXTREME
WESTERN FLORIDA PANHANDLE. THIS SITUATION WILL LIKELY ONLY BE
EXACERBATED WITH ANY ADDITIONAL RAINFALL. A FLASH FLOOD WATCH WILL
SOON BE ISSUED AND IT WILL BE IN EFFECT THROUGH SUNRISE SATURDAY.

IF LARGE DIAMETER HAIL OCCURS...IT WILL MOSTLY BE OVER INTERIOR
SOUTHEASTERN MISSISSIPPI AND EXTREME INTERIOR SOUTHWESTERN ALABAMA
(WEST OF I-65) DURING THE AFTERNOON AND VERY EARLY EVENING.
DAMAGING STRAIGHT LINE WINDS ARE THE PRIMARY THREAT WITH STRONGER
STORMS THAT EVOLVE ALONG THE LINE.  THE TORNADO THREAT IS LOW...BUT
THE LOCAL VERTICAL WIND SHEAR AND ATMOSPHERIC INSTABILITY PROFILE IS
SUPPORTIVE OF TORNADOES DURING THE MID AND LATE AFTERNOON...MAINLY
WEST OF I-65.

THE EVENING AND OVERNIGHT TIMING IS SUCH THAT A THUDERSTORM LINE
WILL MOVE EAST OF I-65 BY MID-EVENING AND PROGRESS EAST OF DESTIN BY
SUNRISE. RAINFALL TOTALS ARE EXPECTED TO BE ONE TO TWO INCHES WITH
ISOLATED TOTALS OF TWO TO FOUR INCHES. THE MAIN CONCERN IS THE
SMALLER RIVERS AND CREEKS OVER THE WESTERN FLORIDA PANHANDLE THAT
COULD RISE TO NEAR OR OVER BANKFULL IN RESPONSE TO THE HEAVY RAINS.

A HIGH RISK OF DANGEROUS RIP CURRENTS CONTINUES ALONG THE BEACHES OF
ALABAMA AND THE WESTERN FLORIDA PANHANDLE TODAY. RIP CURRENTS CAN BE
LIFE THREATENING TO ANYONE ENTERING THE SURF.

MODERATE ONSHORE WINDS AND SEAS RANGING FROM 4 TO 6 FEET OVER THE
MARINE AREA TODAY MAY LEAD TO POTENTIAL HAZARDS FOR THOSE OPERATING
SMALLER MARINE CRAFT.

.DAYS TWO THROUGH SEVEN...EARLY SATURDAY THROUGH THURSDAY.

WITH HIGH PRESSURE STRENGTHENING LATE IN THE WEEKEND...OFFSHORE FLOW
INCREASES ALONG WITH MODERATE SEAS...MAINTAINING THE HAZARD FOR
RECREATIONAL AND COMMERCIAL BOATING.

NO HAZARDOUS WEATHER IS FORECAST TUESDAY THROUGH THURSDAY.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTERS AND EMERGENCY MANAGEMENT SHOULD STAY TUNED TODAY FOR
POSSIBLE ACTIVATION DUE TO THE POTENTIAL OF SEVERE WEATHER.