Winter Storm and Winter Weather in Florida, February 12, 2010

AREA FORECAST DISCUSSION...AVIATION UPDATE
NATIONAL WEATHER SERVICE MOBILE AL
1130 PM CST THU FEB 11 2010

.AVIATION...(06Z ISSUANCE)...OVERCAST VFR DECK CONTINUES TO
GRADUALLY LOWER AS THE LOW LVLS MOISTEN. MVFR CONDITIONS WILL
PREVAIL THROUGH THE EARLY MORNING HOURS. MAINLY -RA AT ALL TAF SITES
NOW AND WILL GRADUALLY TRANSITION TO -RAPL THEN ALL SNOW BY 12Z-15Z.
THIS SYSTEM WILL RAPIDLY MOVE EASTWARD WITH PRECIP ENDING FROM WEST
TO EAST DURING THE EARLY TO MID AFTERNOON HOURS.

...PREVIOUS DISCUSSION ISSUED AT 430 PM CDT...

...WINTER STORM EXPECTED LATE TONIGHT THROUGH FRIDAY...
...SIGNIFICANT ACCUMULATIONS EXPECTED OVER MUCH OF THE AREA...

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT) UPPER LEVEL TROUGH
CONTINUES TO AMPLIFY OVER WESTERN TEXAS THIS AFTERNOON WITH A SURFACE
LOW BEGINNING TO DEEPEN JUST OFF THE SOUTHEAST TEXAS COAST.
ISENTROPIC LIFT WELL AHEAD OF THE MAIN WEATHER SYSTEM HAS ALREADY
RESULTED IN LIGHT PRECIP SPREADING INTO SOUTHERN AND WESTERN PORTIONS
OF THE FORECAST AREA. MUCH OF THIS PRECIP HAS BEEN IN THE FORM OF
SLEET AS THE LOW LEVELS OF THE ATMOSPHERE REMAIN DRY WITH WET BULBS
WELL BELOW FREEZING. TEMPERATURES ARE STILL IN THE UPPER 30S AND
LOWER 40S SO NO ACCUMULATION ISSUES ARE EXPECTED WITH THE SLEET
THROUGH THE EARLY EVENING.

HEAVIER PRECIP WILL BEGIN TO SPREAD IN FROM THE WEST LATE TONIGHT AS
THE UPPER LEVEL SHORTWAVE PIVOTS EAST AND THE SFC LOW BECOMES BETTER
ORGANIZED A COUPLE HUNDRED MILES SOUTH OF THE LOUISIANA COAST. MODEL
CONSENSUS SHOWS THERMAL PROFILES QUICKLY DROPPING TO AT OR BELOW
FREEZING ACROSS THE FAR NORTHERN CWA...SO AS THE MORE INTENSE PRECIP
MAKES ITS WAY IN...WE SHOULD SEE A QUICK CHANGE TO SNOW OVER THE
INTERIOR AFTER MIDNIGHT. FURTHER TO THE SOUTH TOWARD INTERSTATE
10...WE WILL BEGIN TO SEE MORE OF A MIX OF SLEET AND SNOW WITH THE
RAIN. EVEN HEAVIER PRECIP IS ANTICIPATED FROM JUST BEFORE DAYBREAK
THROUGH EARLY FRIDAY AFTERNOON AS THE SFC AND 850 MB LOWS TRACK TO
THE SOUTH OVER THE NORTH CENTRAL GULF OF MEXICO. DEEP LAYER OMEGA AND
DYNAMICAL COOLING TO THE NORTH AND WEST OF THE 850 MB LOW WILL ALLOW
FOR TEMP PROFILES TO QUICKLY COOL...ALLOWING THE SNOW LINE TO
STEADILY SHIFT SOUTH AND EAST THROUGH THE COURSE OF THE DAY. EXPECT
MOSTLY SNOW ALONG AND TO THE NORTHWEST OF I-65 BY 8 AM...WITH SNOW
SPREADING SOUTH AND EAST OF THE I-65 CORRIDOR AS THE MORNING
PROGRESSES. WE WILL HAVE TO CAREFULLY MONITOR THE DEFORMATION BAND
LOCATED ON THE NW SIDE OF THE LOW...WHICH COULD EASILY SUPPORT
HEAVIER MESOSCALE SNOW BANDS AND HIGHER SNOWFALL RATES. THE MAIN
REASON WE TAKE SNOW ALL THE WAY TO THE COAST IS BECAUSE WE BELIEVE
THE DYNAMIC COOLING AND PRECIP RATES WILL BE ENOUGH TO OVERWHELM THE
COLUMN TO BRING IT TO A DEEP NEAR FREEZING ISOTHERMAL LAYER ALL THE
WAY TO THE COAST. THIS IS SUPPORTED BY ALMOST ALL AVAILABLE GUIDANCE.

AS ALWAYS...PREDICTING SNOWFALL ACCUMULATIONS IS CHALLENGING. MODEL
QPF CONTINUES TO BE VERY CONSISTENT WITH NEAR A HALF INCH IN THE NORTH
TO AN INCH ALONG THE COAST. MOST OF THE QPF ACROSS THE NORTH WILL
FALL AS SNOW WITH RATIOS BETWEEN 8:1 AND 10:1. THIS SUPPORTS SNOWFALL
AMOUNTS OF 3-5 INCHES. FURTHER SOUTH THERE IS MORE QPF THAT COULD
RESULT IN EVEN HIGHER SNOWFALL TOTALS. HOWEVER...WITH ISOTHERMAL NEAR
FREEZING PROFILES...WE MAY SEE A LOT OF QPF LOST AS PRECIP BOUNCES
BACK AND FORTH FROM RAIN/SLEET/SNOW BEFORE FINALLY CHANGING OVER TO
ALL SNOW. THEREFORE...WILL FORECAST TOTALS OF 1 TO 3 INCHES TO AS FAR
SOUTH AS THE I-10 CORRIDOR. AGAIN...HIGHER TOTALS ARE POSSIBLE IN ANY
HEAVIER BANDS THAT MATERIALIZE. CLOSER TO THE COAST...WE GENERALLY
EXPECT LESS THAN 1 INCH OF SNOW AS THESE AREAS WILL BE THE LAST TO
TRANSITION TO SNOW AND HAVE THE WARMEST TEMPERATURES. ALL PRECIP
SHOULD SHIFT EAST OF THE AREA BY EARLY FRIDAY EVENING.

TEMPS WILL COOL QUICKLY WITH THE ONSET OF HEAVIER PRECIP SO HAVE LOWS
NEAR 30 NORTH TO MID 30S ALONG THE COAST. WENT WELL BELOW GUIDANCE
FOR HIGHS TOMORROW WITH TEMPS NOT CLIMBING MUCH OUT OF THE MID 30S.
BLACK ICE WILL BE A CONCERN FRIDAY NIGHT AS LOWS DROP INTO THE MID
AND UPPER 20S UNDER CLEARING SKIES. MAY BE COLDER IN SOME LOCATIONS
THAT HAVE A GREATER SNOW PACK. 34/JFB

.LONG TERM...(SATURDAY THROUGH THURSDAY) HIGH PRESSURE BUILDS IN FOR
SATURDAY AND EARLY SUNDAY WITH TEMPS STAYING BELOW NORMAL. NEXT STORM
SYSTEM AND COLD FRONT COMES IN LATE SUNDAY NIGHT INTO EARLY MONDAY.
TEMP PROFILES CURRENTLY LOOK TOO WARM AND PRECIP SHOULD BE ALL
LIQUID. DRY CONDITIONS AND BELOW NORMAL TEMPERATURES PERSIST THROUGH
MIDWEEK. 34/JFB

&&

.MARINE...A STRONG NORTHERLY WIND FLOW WILL DEVELOP LATER TONIGHT
AND CONTINUE THROUGH MID MORNING SATURDAY IN RESPONSE TO A DEEP AREA
OF LOW PRESSURE MOVING EAST OF THE MARINE AREA AND A SURFACE COLD
FRONT MOVING SOUTH OVER THE NORTH CENTRAL GULF. NORTHERLY WINDS OF
20 TO 25 KNOTS WITH HIGHER GUSTS ARE EXPECTED WITH SEAS BUILDING TO
5 TO 7 FEET OUT TO 20 NM...AND 7 TO 9 FEET OUT TO 60 NM BY EARLY
FRIDAY WITH ROUGH CONDITIONS ON AREA BAYS AND SOUNDS. PERIODS OF
RAIN MIXED WITH SLEET AND SNOW REDUCING VISIBILITIES TO ONE MILE OR
LESS WILL ALSO BE LIKELY...BEGINNING LATE TONIGHT TO THE WEST
SPREADING EAST THROUGHOUT THE DAY ON FRIDAY. NORTHERLY WINDS AND
SEAS WILL GRADUALLY DECREASE SATURDAY AFTERNOON THROUGH EARLY SUNDAY
THEN BECOME SOUTH TO SOUTHWEST AND BUILD AHEAD OF ANOTHER STRONG
COLD FRONT LATE SUNDAY THROUGH EARLY SUNDAY NIGHT. THE STRONG COLD
FRONT  WILL MOVE ACROSS THE MARINE AREA OVERNIGHT SUNDAY GIVING WAY
TO A STRONG OFFSHORE FLOW LATE SUNDAY NIGHT THROUGH TUESDAY
MORNING.  32/EE

&&

.FIRE WEATHER...NO CONCERNS WITH WINTER WEATHER IMPACTING THE AREA
THROUGH FRIDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
MOBILE      32  36  28  48 / 100 100  05  05
PENSACOLA   34  37  31  49 /  90 100  05  05
DESTIN      33  42  35  48 /  80 100  05  05
EVERGREEN   31  35  25  46 /  80 100  05  05
WAYNESBORO  30  34  25  46 /  90 100  05  05
CAMDEN      30  34  24  46 /  70 100  05  05
CRESTVIEW   33  36  27  49 /  70 100  05  05

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...WINTER STORM WARNING FROM MIDNIGHT FRIDAY TO 6 PM FRIDAY FOR THE
     FOLLOWING ZONES: BUTLER...CHOCTAW...CLARKE...CONECUH...
     COVINGTON...CRENSHAW...ESCAMBIA...LOWER BALDWIN...LOWER
     MOBILE...MONROE...UPPER BALDWIN...UPPER MOBILE...
     WASHINGTON...AND WILCOX.

FL...WINTER STORM WARNING FROM MIDNIGHT FRIDAY TO 6 PM FRIDAY FOR THE
     FOLLOWING ZONES: COASTAL ESCAMBIA...COASTAL OKALOOSA...
     COASTAL SANTA ROSA...INLAND ESCAMBIA...INLAND OKALOOSA...
     AND INLAND SANTA ROSA.

MS...WINTER STORM WARNING FROM MIDNIGHT FRIDAY TO 6 PM FRIDAY FOR THE
     FOLLOWING ZONES: GEORGE...GREENE...PERRY...STONE...AND
     WAYNE.

GM...SMALL CRAFT ADVISORY FROM MIDNIGHT FRIDAY TO 9 AM SATURDAY 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.

&&

HAZARDOUS WEATHER OUTLOOK...CORRECTION TO UPDATE...
NATIONAL WEATHER SERVICE MOBILE AL
251 PM CST THU FEB 11 2010

ALZ051>064-FLZ001>006-GMZ630-650-655-670-675-MSZ067-075-076-078-
079-122300-
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-
251 PM CST THU FEB 11 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEASTERN
MISSISSIPPI...SOUTHWESTERN AND SOUTH CENTRAL ALABAMA...THE WESTERN
FLORIDA PANHANDLE...AND THE ADJACENT GULF COASTAL WATERS OF ALABAMA
AND NORTHWEST FLORIDA.

.DAY ONE...TONIGHT AND FRIDAY

...WINTER STORM WARNING IS IN EFFECT THROUGH 6 PM CST FRIDAY...

THE COMBINATION OF A SURFACE LOW PRESSURE SYSTEM MOVING EASTWARD
ACROSS THE CENTRAL GULF OF MEXICO...DEEP MOISTURE...AND COLD AIR
POURING INTO OUR REGION FROM THE NORTH...WILL SET THE STAGE FOR
SIGNIFICANT SNOWFALL ACCUMULATIONS LATE TONIGHT AND FRIDAY. RAIN AND
SLEET WILL BEGIN TO CHANGE OVER TO WET SNOW AFTER MIDNIGHT TONIGHT
OVER THE INTERIOR COUNTIES...ESPECIALLY NORTH OF A
WIGGINS...ATMORE...TO ANDALUSIA LINE. THE WET SNOW LINE WILL MOVE
PROGRESSIVELY SOUTHWARD TOWARD THE COAST ON FRIDAY. SIGNIFICANT TOTAL
SNOW ACCUMULATIONS ARE EXPECTED ALONG AND NORTH OF INTERSTATE 10.
PLEASE REFER TOT HE WINTER STORM WARNING (BHMWSWMOB) FOR ALL SPATIAL
AND TIMING DETAILS.

SOME AREA RIVERS REMAIN IN ACTION OR MINOR FLOOD STAGE TONIGHT AND
FRIDAY. PLEASE REFER TO THE LATEST RIVER FORECASTS FOR MORE SPECIFIC
INFORMATION ON RIVERS IN YOUR AREA.

OVER THE MARINE AREA...SMALL CRAFT ADVISORY IN EFFECT AT MIDNIGHT.
A STRONG OFFSHORE FLOW WILL DEVELOP AFTER MIDNIGHT...WITH SEAS
BUILDING TO 5 FEET NEARSHORE AND UP TO 9 FEET WELL OFFSHORE.  THESE
CONDITIONS WILL BE HAZARDOUS TO SMALL CRAFT.  VISIBILITIES WILL BE
LIMITED AT TIME IN SNOW TONIGHT AND FRIDAY.

.DAYS TWO THROUGH SEVEN...FRIDAY EVENING THROUGH THURSDAY

SNOWFALL WILL END FROM THE WEST FROM LATE AFTERNOON AND INTO EARLY
EVENING. TOTAL SNOWFALL ACCUMULATIONS WILL BE AS HIGH THREE TO FIVE
INCHES IN THE INTERIOR COUNTIES RANGING TO AROUND AN INCH NEAR THE
BEACHES...AND MAINLY ON GRASSY SURFACES.

BLACK ICE WILL OCCUR FOR SEVERAL DAYS WHERE SNOW FELL AND MELTS
DURING THE AFTERNOONS AND THEN RE-FREEZES DURING THE EVENING. THIS
WILL BE ESPECIALLY PROBLEMATIC WITH BRIDGES AND OVERPASSES WHERE
COLD AIR CAN FLOW UNDERNEATH.

OVER THE MARINE AREA...THE STRONG OFFSHORE FLOW WILL PERSIST THROUGH
FRIDAY NIGHT. THE WINDS WILL GRADUALLY SUBSIDE OVER THE WEEKEND AS
WEAK HIGH PRESSURE BUILDS FROM THE NORTHWEST...BUT WILL REDEVELOP
AGAIN LATE SUNDAY. THE STRONG NORTHERLY WINDS WILL CREATE HAZARDOUS
CONDITIONS TO SMALL CRAFT...AND ADVISORIES WILL LIKELY REMAIN IN
EFFECT.

SOME AREA RIVERS WILL REMAIN IN ACTION OR FLOOD STAGE THROUGH EARLY
WEEKEND. PLEASE REFER TO THE LATEST RIVER FORECASTS FOR MORE
SPECIFIC INFORMATION ON RIVERS IN YOUR AREA.

BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE END OF NEXT WEEK
WITH HIGHS IN THE 40S AND 50 AND LOWS IN THE 20S AND 30S.  MOST
AREAS WILL HAVE A FROST OR FREEZE EACH NIGHT...EXCEPT ALONG THE
IMMEDIATE COAST ON SOME OF THE NIGHTS.  FOR EXACT TEMPERATURE
DETAILS...REFER TO THE MOBILE ALABAMA NWS "POINT AND CLICK" FORECAST
AT WWW.SRH.NOAA.GOV/MOB.

/23 JMM

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT OFFICIALS FOR
WINTER WEATHER OPERATIONS WILL BE REQUIRED FROM MIDNIGHT TONIGHT
THROUGH FRIDAY.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOBILE AL
1002 PM CST THU FEB 11 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0950 PM     SNOW             WAYNESBORO              31.67N 88.65W
02/11/2010  U0.0 INCH        WAYNE              MS   EMERGENCY MNGR

            WAYNE COUNTY OFFICIALS REPORTED PRECIPITATION HAS CHANGED
            OVER FROM RAIN TO SNOW. PUBLIC REPORTED SOME SLIGHT
            ACCUMULATIONS ON VEHICLES.

&&

DSHEPHERD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOBILE AL
1145 PM CST THU FEB 11 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0925 PM     SNOW             MILLRY                  31.63N 88.31W
02/11/2010  U0.0 INCH        WASHINGTON         AL   BROADCAST MEDIA

            SNOW REPORTED...NO ACCUMULATIONS

&&

DSHEPHERD