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000
FXUS64 KJAN 261600
AFDJAN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
1050 AM CDT SAT JUL 26 2014

.UPDATE...THE 12Z SATURDAY JAN SOUNDING SHOWED AN INCREASE IN LOW
LEVEL MOISTURE FROM FRIDAY AND SURFACE DEW POINTS WERE RUNNING
WARMER IN THE MID 70S AT MOST SITES THIS MORNING. PWS WERE BACK
ABOVE AN INCH AND A HALF...UP FROM AN INCH AND A QUARTER FRIDAY.
WATER VAPOR IMAGERY SHOWED THE ANTICYCLONIC FLOW OVER OUR CWA AROUND
THE EASTERN PERIPHERY OF THE MID LEVEL RIDGE CENTERED OVER THE
SOUTHERN PLAINS. THIS HAS HELPED LIMIT CLOUD COVER OVER OUR REGION
SO FAR AND HAS ALLOWED FOR A DECENT WARM UP THIS MORNING.
TEMPERATURES AT 10 AM WERE RUNNING A COUPLE DEGREES WARMER THAN
EXPECTED AND HAVE INCREASED AFTERNOON HIGHS A COUPLE DEGREES CLOSER
TO 00Z SAT GFSMOS TEMPS. THE HIGHER TEMPS COMBINED WITH THE HIGHER
HUMIDITY WILL RESULT IN HEAT INDEX VALUES TOPPING OUT HIGHER IN THE
101-105F RANGE TODAY. HI-RES MODELS INDICATE SOME SEA BREEZE
CONVECTION THIS AFTERNOON. THIS ACTIVITY MAY SPREAD CLOSE TO OUR
SOUTHERN ZONES BUT CONSIDERING THE STOUT INVERSION ON THE JAN
SOUNDING AND NORTHERLY MID LEVEL FLOW HAVE HELD OFF ADDING MENTION
OF ISOLATED COVERAGE FOR NOW. /22/

&&

.AVIATION...EXPECT VFR CONDITIONS THROUGH 10Z SUNDAY...BUT PATCHY
FOG COULD BRING TEMPO MVFR CONDITIONS IN FOG FROM 10-13Z. LIGHT
WINDS WILL BECOME SOUTHWEST TO WEST AT 5-8KTS AND BECOME LIGHT AFTER
00Z./17/

&&

.PREV DISCUSSION... /ISSUED 359 AM CDT SAT JUL 26 2014/

SHORT TERM...TODAY THROUGH SUNDAY NIGHT...A QUIET BUT VERY WARM
WEEKEND WILL PREVAIL ACROSS THE ARKLAMISS. THE EASTERN EDGE OF A
594DM UPPER RIDGE WILL PREVAIL ACROSS THE AREA TODAY WITH PARTLY
CLOUDY SKIES AND HIGHS IN THE LOW 90S. LITTLE WILL CHANGE ON SUNDAY
..BUT MOISTURE WILL BEGIN TO INCREASE ACROSS THE AREA WITH PWATS
CLIMBING TO AROUND 1.8 INCHES. WITH THE STRONG UPPER RIDGE IN PLACE
EXPECT THE AREA TO REMAIN DRY THOUGH...UNDER PARTLY CLOUDY SKIES
ONCE AGAIN. AFTERNOON HIGHS WILL BE UP ANOTHER COUPLE OF DEGREES IN
THE MID 90S ACROSS MUCH OF THE AREA.

CHANGES ARE ON THE WAY BEGINNING SUNDAY NIGHT AS THE UPPER RIDGE
BEGINS TO BREAK DOWN AND UPPER TROUGHING DEEPENS OVER THE EASTERN
CONUS. BOTH THE GFS/ECMWF SUGGEST THE A COLD FRONT WILL MOVE INTO
THE NORTHERN PORTIONS OF THE AREA BY MONDAY MORNING WITH INCREASING
CHANCES FOR SHOWERS AND THUNDERSTORMS OVER THESE AREAS. STUCK PRETTY
CLOSE TO GUIDANCE TEMPS THROUGH THE PERIOD...BUT DID CUT BELOW
GUIDANCE HIGHS SLIGHTLY BOTH SATURDAY AND SUNDAY./15/

LONG TERM...MONDAY THROUGH SATURDAY...RATHER ANOMALOUS PATTERN
SETTING UP FOR NEXT WEEK AS FLOW BECOMES HIGHLY AMPLIFIED WITH
RIDGE BUILDING IN THE WEST AND TROF DIGGING OVER THE EAST. THIS
INCREASINGLY NW MID LEVEL FLOW WILL ALLOW A SURFACE COLD FRONT TO
QUICKLY MOVE THROUGH THE FORECAST AREA MONDAY. BOTH ECMWF AND GFS
AGREE THAT SOME OF THE STORMS MAY BE STRONG OVER CENTRAL AND
SOUTHERN AREAS DURING THE HEAT OF THE AFTERNOON AS CAPES REACH NEAR
5000 J/KG ALONG WITH VERTICAL TOTALS IN THE UPPER 20S. WILL HAVE TO
WATCH FOR CONSISTENCY IN THIS POTENTIAL IN FUTURE RUNS.

MOVING INTO MID WEEK...DRY AIRMASS WILL SETTLE OVER THE REGION
PROVIDING COOL OVERNIGHT READINGS IN THE 60S WITH STILL WARM
AFTERNOONS MAINLY IN THE LOWER 90S. THE MID LEVEL NORTHWEST FLOW
LOOKS TO OFFER A SURPRISE SHORTWAVE BY THURSDAY. WHILE THE GFS DOES
HANDLE THIS WAVE...IT MAINTAINS A DRY SOLUTION. WENT CLOSER TO THE
WETTER ECMWF WHICH SEEMS MORE REASONABLE.

MOVING FORWARD INTO THE END OF THE WEEK...BOTH MODELS WANT TO DIG
THE COLD CORE LOW OUT OF THE GREAT LAKES INTO THE TN VALLEY BY
SATURDAY. AS THIS OCCURS...INCREASED CLOUD COVER AND THE DEVELOPMENT
OF SCATTERED SHOWERS AND THUNDERSTORMS LOOK PROBABLE DUE TO
INCREASED INSTABILITY./26/

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       95  74  94  75 /   2   5   2   8
MERIDIAN      95  72  93  73 /   2   5   4   9
VICKSBURG     95  72  94  72 /   2   5   3   7
HATTIESBURG   96  75  95  76 /   6   8   5   9
NATCHEZ       93  73  93  75 /   5   5   5   8
GREENVILLE    96  75  95  73 /   1   5   6  18
GREENWOOD     96  74  94  72 /   1   4   5  17

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&

$$

22/17/15/26