Winter Storm and Winter Weather in Arkansas, January 20, 2011

AREA FORECAST DISCUSSION...UPDATE FOR AVIATION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1140 PM CST WED JAN 19 2011

.AVIATION...
THE OVERNIGHT WILL START WITH MVFR CEILINGS AR ALL TAF SITES...WITH
PATCHY IFR OVER THE STATE. A LOW SURFACE PRESSURE OVER TX AND A
FRONTAL BOUNDARY NEAR THE AR AND MO STATE LINE. OVERNIGHT...THIS
SYSTEM WILL SLOWLY MOVE EAST AND BRING LIGHT RAIN...BECOMING A RAIN
AND SNOW MIX...THEN ALL LIGHT SNOW BY THURSDAY MORNING. TOWARD
THURSDAY SUNRISE...LIGHT RAIN...OR A MIX OF LIGHT RAIN AND
SNOW...WILL BEGIN TO SPREAD INTO CENTRAL AND WESTERN PARTS OF THE
STATE. AREAS OF IFR CONDITIONS WILL BECOME MORE WIDESPREAD. MAINLY
RAIN WILL BE SEEN OVER SOUTHERN AR THURSDAY MORNING. ON
THURSDAY...AND LIGHT TO MODERATE SNOW OVER NORTHERN AR...RAIN
BECOMING SLEET TO SNOW IN THE AFTERNOON. RAIN SOUTH AND CHANGING
OVER TO SLEET TO SNOW LATE THURSDAY. MAINLY SE TO E WINDS 3 TO 8
KNOTS OVERNIGHT...THEN WINDS SHIFTING MORE N FROM NORTHERN TO
SOUTHERN AREAS THROUGH THE DAY THURSDAY. (59)

&&

.PREV DISCUSSION... /ISSUED 530 PM CST WED JAN 19 2011/

UPDATE...
GOING FORECAST ON TARGET. IT LOOKS LIKE A HEAVIER BAND OF SNOW
MAY DEVELOP ALONG THE MISSOURI BORDER. FORECAST QPF AND A 15 TO 1
SNOW TO LIQUID RATIO NETTING 3 TO 5 INCH ACCUMULATIONS IN AREAS
LIKE JASPER...HARRISON IN MOUNTAIN HOME. POSTED A WINTER STORM
WARNING ACROSS SIX COUNTIES IN THE EXTREME NORTH LATE
TONIGHT/THURSDAY. REST OF FORECAST LOOKS GOOD. (46)

SHORT TERM...TONIGHT THROUGH SATURDAY
NOT A LOT OF APPRECIABLE CHANGES WILL BE MADE IN THE SHORT TERM AS
MODELS REMAIN IN GOOD AGREEMENT WITH THIS UPCOMING EVENT. GFS HAS
REMAINED CONSISTENT WITH ITS THINKING AND HAS GOOD SUPPORT FROM THE
ECMWF AND THE SHORT RANGE ENSEMBLES AND IS THE PREFERRED SOLUTION
THIS AFTERNOON.

LATEST MOISTURE CHANNEL IMAGERY AND SURFACE OBSERVATIONS INDICATE
SURFACE LOW PRESSURE STARTING TO GET ITS ACT TOGETHER OVER THE
NORTHEAST NEW MEXICO/TEXAS PANHANDLE AREA. SYSTEM WILL BEGIN TO LIFT
OUT AND TAP INTO AVAILABLE MOISTURE TO BRING ANOTHER DOSE OF WINTERY
WEATHER TO THE FORECAST AREA. SURFACE SYSTEM WILL BE AIDED BY AN
UPPER LEVEL DISTURBANCE DROPPING OUT OF THE ROCKIES AND AN ARCTIC
BOUNDARY BUT ON THE POSITIVE...ALL INDICATIONS ARE IT WILL BE A
QUICK MOVING SYSTEM.

MODELS ALL AGREE THAT SNOW WILL LIKELY IMPACT THE MAJORITY IF NOT
ALL OF THE FORECAST AREA THROUGH THURSDAY EVENING. BIGGEST FORECAST
CONCERNS WITH THIS SYSTEM ARE THE TYPE OF PRECIPITATION THAT WILL BE
SEEN BEFORE THE CHANGEOVER AND THE FINAL AMOUNT OF THE WHITE STUFF
EXPECTED. THIS SCENARIO OF A CHANGE OVER TO ALL SNOW IS SUPPORTED BY
ALL THERMAL PROFILES AND FORECAST SOUNDINGS/BUFKIT DATA.

OVERALL...SNOWFALL AMOUNTS NOT EXPECTED TO BE EXTREME AS NORTHEAST
TO NORTHWEST WINDS DURING THE EVENT WILL KEEP DEEP MOISTURE AT BAY
WITH MOST OF THE PRECIPITATION CONFINED TO THE ADVANCING BAROCLINIC
ZONE. PRECIPITATION IS EXPECTED TO INITIATE OVER THE NORTHWEST PART
OF THE FORECAST AREA EARLY THURSDAY MORNING. MAINLY SNOW IS EXPECTED
HERE ALTHOUGH A BRIEF PERIOD OF SLEET AND EVEN PLAIN OLD RAIN CAN
NOT BE RULED OUT. ANY ICE ACCUMULATIONS WOULD BE MINIMAL.

ACROSS CENTRAL AND WESTERN SECTIONS OF THE STATE...STILL LOOKING AT
PRECIPITATION TO START OUT BY MID MORNING AS A COLD RAIN MIXED WITH
A LITTLE FREEZING RAIN AND SLEET POSSIBLE. STRONG COLD AIR ADVECTION
WILL THEN TRANSFORM THE MIXED BAG OVER TO SNOW DURING THE AFTERNOON
HOURS. AGAIN...ANY ICE ACCUMULATIONS WOULD BE MINIMAL.

AS FAR AS THE SOUTH IS CONCERNED...PRECIPITATION WILL BEGIN NO
LATER THAN NOON WITH JUST A COLD RAIN THE PREDOMINATE PRECIPITATION
TYPE. SNOW WILL MIX WITH RAIN BEFORE ENDING AS JUST SNOW BEFORE ALL
PRECIPITATION ENDS ACROSS THE FORECAST AREA THURSDAY EVENING.

AS FAR AS ACCUMULATIONS ARE CONCERNED...STILL EXPECTING THE HIGHEST
AMOUNTS ACROSS THE NORTHERN COUNTIES...WITH ACCUMULATIONS OF 2-4
INCHES EXPECTED GENERALLY ALONG AND NORTH OF A CLARKSVILLE TO
CLINTON TO NEWPORT LINE. RIGHT ALONG THE MISSOURI BORDER...SNOWFALL
AMOUNTS WILL BE CLOSER TO THE FOUR INCH MARK. A GENERAL ONE TO TWO
INCH SNOWFALL IS EXPECTED ACROSS CENTRAL SECTIONS...ROUGHLY ALONG
AND NORTH OF A MENA TO LITTLE ROCK TO BRINKLEY LINE WITH THE HIGHER
AMOUNTS ACROSS THE NORTHERN PART OF THIS SWATH. ACROSS THE
SOUTH...ONLY MINOR ACCUMULATIONS ARE EXPECTED AT THIS TIME...FROM A
DUSTING TO MAYBE A HALF INCH.

WILL CONTINUE TIMING AND PLACEMENT OF THE CURRENT HEADLINES WITH
PRECIPITATION ENDING FROM WEST TO EAST DURING THE AFTERNOON HOURS
WITH ALL PRECIPITATION OUT OF HERE BY EARLY EVENING. TEMPERATURES
WILL DROP INTO TEENS TO MID 20S FOR THURSDAY NIGHT ENSURING ANY
THING LEFT BEHIND WILL FREEZE.

ARCTIC HIGH PRESSURE WILL SETTLE ACROSS THE REGION FRIDAY WITH WELL
BELOW NORMAL TEMPS EXPECTED. SOME MODERATION IN TEMPERATURES IN
EXPECTED ON SATURDAY BUT WILL TRIM BACK HIGHS ACROSS THE NORTH WITH
LINGERING SNOW PACK. A WEAK SYSTEM WILL PASS TO THE NORTH FRIDAY
NIGHT AND EARLY SATURDAY BUT ONLY AN INCREASE IN CLOUDS IS EXPECTED.

LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
NORTHWEST FLOW ALOFT SATURDAY NIGHT WILL BECOME SOUTHWEST BY MONDAY
MORNING AS A TROUGH APPROACHES ARKANSAS. LOW PRESSURE OVER THE UPPER
MIDWEST WILL MOVE SOUTHEAST MONDAY AND TUESDAY AS IT MOVES INTO THE
OHIO RIVER VALLEY. NORTHWEST FLOW RETURNS TO ARKANSAS TUESDAY
EVENING THROUGH WEDNESDAY.

SURFACE HIGH PRESSURE WILL BE OVER ARKANSAS SATURDAY NIGHT...BUT
WILL QUICKLY MOVE EAST. LOW PRESSURE WILL MOVE OUT OF TEXAS SUNDAY
AS MOISTURE INCREASES ACROSS ARKANSAS. WITH COLD AIR IN PLACE
HOWEVER...THERE WILL BE A SLIGHT CHANCE OF LIGHT SNOW SUNDAY MORNING
ACROSS THE WEST AND NORTH...CHANGING TO ALL RAIN IN ALL AREAS BY
LATE SUNDAY. AS THE LOW MOVES SOUTH AND EAST OF ARKANSAS COLDER AIR
WILL FILTER INTO THE STATE AND PRECIPITATION WILL CHANGE TO SNOW.
SNOW WILL BE LIKELY ACROSS THE NORTH AND CENTRAL SECTIONS SUNDAY
NIGHT INTO MONDAY MORNING. IT IS POSSIBLE CENTRAL SECTIONS COULD
WARM UP TO CHANGE THE PRECIP TO RAIN MONDAY AFTERNOON AS THE LOW
MOVES THROUGH THE GULF. PRECIP CHANCES WILL TAPER OFF MONDAY
EVENING. GFS AND ECMWF ARE DIFFERENT FOR TUESDAY WITH MORE MOISTURE
ON THE ECMWF THAN THE GFS. WILL SIDE WITH THE SURFACE HIGH PRESSURE
AND DRY WEATHER OVER ARKANSAS TUESDAY AND WEDNESDAY AT THIS TIME.
BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE PERIOD.

&&

.LZK WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 9 AM TO 9 PM CST THURSDAY FOR
CLEBURNE-CONWAY-FAULKNER-GARLAND-INDEPENDENCE-JACKSON-LONOKE-
MONROE-MONTGOMERY-PERRY-POLK-PRAIRIE-PULASKI-SALINE-SCOTT-SHARP-
WHITE-WOODRUFF.

WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM CST THURSDAY FOR IZARD-
JOHNSON-LOGAN-POPE-STONE-VAN BUREN-YELL.

WINTER STORM WARNING FROM 3 AM TO 6 PM CST THURSDAY FOR BAXTER-
BOONE-FULTON-MARION-NEWTON-SEARCY.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
800 PM CST WED JAN 19 2011

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-201045-
ARKANSAS-BAXTER-BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-CLEVELAND-
CONWAY-DALLAS-DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-HOT SPRING-
INDEPENDENCE-IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-LOGAN-LONOKE-
MARION-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-POPE-
PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-WHITE-
WOODRUFF-YELL-
800 PM CST WED JAN 19 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A LARGE PART OF ARKANSAS.

.DAY ONE...TONIGHT

SNOW IS EXPECTED TO DEVELOP OVER NORTHWEST SECTIONS OF ARKANSAS
SHORTLY AFTER MIDNIGHT. THE SNOW MAY BE MIXED BRIEFLY WITH SLEET BUT
A CHANGEOVER TO ALL SNOW WILL OCCUR FAIRLY QUICKLY. SNOW
ACCUMULATIONS MAY TOTAL A HALF AN INCH ACROSS THE FAR NORTHWEST
CORNER OF THE FORECAST AREA BY MORNING. A WINTER STORM WARNING
BEGINS AT 3 AM FOR THE NORTHWEST PART OF THE FORECAST AREA. THE
WINTER STORM WARNING WILL CONTINUE THROUGH 6 PM THURSDAY.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

AS THE STORM SYSTEM MOVES ACROSS ARKANSAS ON THURSDAY...WINTRY
WEATHER WILL EXPAND SOUTH ACROSS THE CENTRAL PART OF THE STATE. A
WINTER WEATHER ADVISORY IS IN EFFECT FOR CENTRAL SECTIONS OF
ARKANSAS FROM 9 AM TO 9 PM THURSDAY.

ACROSS CENTRAL SECTIONS OF THE STATE...PRECIPITATION WILL INITIALLY
START AS A MIX OF RAIN...AND POSSIBLY SLEET AND FREEZING RAIN DURING
THE LATE MORNING HOURS THURSDAY...BEFORE TURNING TO SNOW LATER IN
THE DAY. THE MAJORITY OF THE PRECIPITATION WILL REMAIN IN LIQUID
FORM OVER THE SOUTH ALTHOUGH A BRIEF PERIOD OF SNOW IS POSSIBLE ON
THE TAIL END OF THE STORM.

THE STORM IS A VERY QUICK MOVER AND ALL PRECIPITATION WILL BE OUT OF
THE STATE BY MID THURSDAY EVENING. WIDESPREAD 2 TO 4 INCH SNOWFALL
AMOUNTS ARE EXPECTED IN THE NORTHERN THIRD OF THE STATE WITH CENTRAL
PARTS RECEIVING 1 TO 3 INCHES. FAR NORTHERN PARTS OF THE STATE COULD
SEE UPWARDS OF 5 INCHES OF SNOW THURSDAY. AREAS IN A CORRIDOR FROM
HOT SPRINGS TO PINE BLUFF COULD PICK UP A DUSTING TO AN INCH OF NEW
SNOW WITH LOCATIONS SOUTH OF THIS SEEING LITTLE ACCUMULATION.

TEMPERATURES THURSDAY NIGHT WILL BE VERY COLD BEHIND THE SYSTEM WITH
LOWS IN THE TEENS IN MANY PLACES WITH SINGLE DIGITS IN THE NORTH.

ANOTHER STORM SYSTEM WILL MOVE THROUGH ARKANSAS LATE SUNDAY AND INTO
MONDAY WITH A SHOT AT MORE WINTRY PRECIPITATION.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED. HOWEVER...SPOTTERS ARE
ENCOURAGED TO CALL IN TOTAL SNOW AMOUNTS AFTER THIS EVENT.

&&

VISIT NWS LITTLE ROCK ON THE WEB. GO TO HTTP://WEATHER.GOV AND
CLICK ON CENTRAL ARKANSAS.

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