Area Forecast Discussion
Issued by NWS Atlanta, GA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KFFC 082033
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
333 PM EST MON FEB 8 2016


...ACCUMULATING SNOW AND BLACK ICE POTENTIAL CONTINUES FOR
PORTIONS OF NORTH GEORGIA THROUGH TUESDAY ALONG WITH DANGEROUS
WIND CHILL VALUES FOR FAR NORTHEAST GEORGIA BEGINNING TUESDAY
MORNING...

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

COMPLICATED FORECAST GIVEN THE ENVIRONMENT OF STRONG BROAD UPPER
LOW AND SHALLOW UNSTABLE LAYER PROVIDING CONVECTIVE RAIN/SNOW
SHOWER GENERATION WITH LOW QPF AND PWATS. MAIN AREAS OF IMPACT
WITH ACCUMULATING SNOW CONTINUES TO BE THE HIGHER ELEVATIONS OF
FAR NORTH GEORGIA AS LIGHT SNOW CONTINUES TO BE OBSERVED THOUGH
THERMAL PROFILE TRANSITION SHOWS QUICK SUB-FREEZING COLUMN
FARTHER SOUTH THAT BATTLES A DRIER NEAR-SFC LAYER. ALL IN ALL
STILL LOOKING AT 1-2 INCHES IN HIGHER ELEVATIONS WITH LOCALLY
HIGHER BEFORE FORCING/MOISTURE TRANSLATES AWAY THROUGH TUESDAY
NIGHT. SOME LIGHT SNOW SHOWER OR FLURRY POTENTIAL OVERNIGHT FOR
ALL OF NORTH GEORGIA INCLUDING THE ATLANTA METRO AREA AND AS FAR
SOUTH AS NORTHWEST PORTIONS OF CENTRAL GEORGIA WITH LITTLE TO NO
ACCUMULATION EXPECTED...ALTHOUGH THE BIGGER CONCERN MAY BE IF A
LIGHT BAND OF SNOW SETS UP FARTHER SOUTH IN PORTIONS OF NORTH
GEORGIA MIDDAY TUESDAY INTO AFTERNOON...WHICH CANNOT RULE OUT A
QUARTER INCH OR LESS ACCUMULATION. THIS HAS HAD SOME RUN TO RUN
CONSISTENCY IN THE SHORT TERM GUIDANCE SO WILL NEED TO CLOSELY
MONITOR FOR ADDITIONAL IMPACTS. WILL BE LIKELY COVERING AREAS
FARTHER SOUTH FROM WINTER WEATHER ADVISORY ZONE WITH SPECIAL
WEATHER STATEMENT.

TO ADD MORE WINTRY HAZARDS IN THE MIX...THE BITTER COLD AIRMASS
ADVECTING INTO THE AREA ALONG WITH GRADIENT WINDS RESULT IN WIND
CHILL VALUES WITHIN ADVISORY LEVEL FOR THE FAR NORTHEAST MOUNTAINS
/BELOW 5 DEGREES/...AND ACTUALLY APPROACH THE UPPER END OF WIND
CHILL WARNING CRITERIA /NEAR 10 BELOW/ BY THURSDAY MORNING. THE
CURRENT WIND CHILL ADVISORY AREA /JUST ISSUED WITH AFTERNOON
PACKAGE/ WILL LIKELY BE EXTENDED FARTHER WEST AND SOUTH AS THE
COLD GETS FURTHER REINFORCED THROUGH MIDWEEK. PLEASE MONITOR
UPDATES AS CHANGES ARE LIKELY.

BAKER

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
STRONG HIGH PRESSURE BUILDING INTO THE SOUTHEAST MID WEEK. A SHORT
WAVE MOVING THROUGH THE SOUTHEAST THURSDAY NIGHT INTO FRIDAY MAY
BRING A CHANCE FOR PRECIPITATION DURING THAT TIME. GFS/ECMWF STILL
DIFFER ON LOCATION AND AMOUNT OF MOISTURE WITH THIS SYSTEM. HAVE
CONTINUED WITH LOW POPS FOR FRIDAY INTO FRIDAY NIGHT...BUT ADDED A
CHANCE EXTREME NORTHEAST THURSDAY NIGHT. HAVE TRIED TO TWEAK
PRECIP TYPE BASED ON TEMPERATURES. ECMWF SHOWING COLDER FOR THE
WEEKEND AND TEMPERATURES WERE TRENDED DOWN A BIT. PREVIOUS
DISCUSSION IS INCLUDED BELOW.

41

PREV DISCUSSION... /ISSUED 620 AM EST MON FEB 8 2016/
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... 500MB TROUGH AND
STRONG SHORTWAVE ENERGY WILL BEGIN TO SHIFT OFF TO THE EAST
TUESDAY NIGHT. SO ANY LINGERING ISO/SCT SNOW SHOWERS WILL TAPER
OFF DURING THIS PERIOD. SINCE THE ATMOS IS PRETTY DRY AT THIS
POINT AND VERY LITTLE ADDITIONAL SNOW IS ANTICIPATED.

THE FORECAST SHOULD REMAIN DRY FOR WEDNESDAY AND THURSDAY AS HIGH
PRESSURE SETTLES OVER THE AREA AND THE MID LEVELS REMAIN FAIRLY
QUIET. CWFA WILL REMAIN IN NW FLOW FOR MUCH OF THE REMAINDER OF THE
LONG TERM.

THE GFS AND ECMWF ARE PROGGING A PRETTY GOOD SHORTWAVE TO DIG DOWN
IN THE FLOW FOR THE END OF THE WEEK. THIS IS ALSO COINCIDENT WITH A
LOW PRESSURE WAVE MOVING EAST ACROSS THE SOUTHEAST STATES. AN OLD
FRONTAL BOUNDARY ACROSS THE NORTHERN GULF/FLORIDA PANHANDLE WILL
START PUSHING NORTH LATER THURSDAY INTO FRIDAY. THE WAVE OF LOW
PRESSURE IS PROGGED TO DEVELOP FURTHER WEST AND MOVE EAST ALONG THE
BOUNDARY THROUGH LATE FRIDAY. ISENTROPIC LIFT ALONG AND NORTH OF THE
BOUNDARY MAY PRODUCE SOME LIGHT PRECIPITATION. MODELS HAVE
CONSISTENTLY KEPT POPS AT 20 PERCENT OR LESS DURING THIS PERIOD.
HOWEVER...THE LATEST ECMWF IS COMING IN A LITTLE WETTER THAN
PREVIOUS RUNS. THE SYSTEM IS STILL A LITTLE FAR OUT...SO WILL GO
WITH PERSISTENCE FOR NOW AND KEEP POPS CAPPED AT 20 PERCENT OR LESS
FRIDAY AND FRIDAY NIGHT.

PTYPE MAY BE AN ISSUE WITH THE FRIDAY SYSTEM. DURING THE DAY
FRIDAY...TEMPS LOOK WARM ENOUGH FOR ALL RAIN. HOWEVER...FRIDAY NIGHT
WILL BE A LITTLE TRICKIER. THE PRECIPITATION MAY END AS A WINTRY MIX
OF PRECIPITATION. MODEL SOUNDINGS ARE SHOWING SOME POTENTIAL FOR
LIGHT FREEZING RAIN/DRIZZLE...MAINLY ACROSS NORTHERN GA. ITS STILL
TOO FAR OUT TO NAIL DOWN EXACT PTYPES...SO WILL GO WITH RA OR SN.
INTERESTED PARTIES SHOULD REMAIN WEATHER AWARE...ESPECIALLY SINCE
PTYPE ISSUES ARE INVOLVED.

THE WEEKEND LOOKS DRY AS STRONG HIGH PRESSURE BUILDS OVER THE AREA.
THE NEXT FRONT MAY BEGIN TO IMPACT THE CWFA BY EARLY NEXT WEEK.

NLISTEMAA

&&

.AVIATION...
18Z UPDATE...
INITIAL LOW END VFR CIGS FOR NORTHERN SITES SHOULD LOWER TO MVFR
OVERNIGHT AND PERSIST INTO TUESDAY. CHANCE FOR PRECIP IS TRICKY
BUT LOOKS LIKE ENOUGH TO WARRANT A TEMPO FOR INITIAL -SHRA THEN
TRANSITION TO -SHSN AFTER NEAR 05Z IN PROB30 GROUPS FOR KATL AND
NEARBY SITES. ANY DEVELOPMENT IS EXPECTED TO HAVE LITTLE TO NO
ACCUMULATION AND THERE IS MORE UNCERTAINTY WITH A POSSIBLE LIGHT
BAND OF SNOW FORMING NEAR MIDDAY TUESDAY INTO THE AFTERNOON AS FAR
SOUTH AS KATL AS WELL. WILL NEED TO KEEP MONITORING FOR UPDATES AS
WARRANTED. OTHERWISE WINDS WEST TO WNW 7-10 KTS WITH GUSTS 18-25
KTS.

//ATL CONFIDENCE...18Z UPDATE...
LOW ON -SHSN CHANCE/COVERAGE.
HIGH ON ALL ELSE.

BAKER

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          29  39  23  38 /  30  10   5   5
ATLANTA         29  36  23  37 /  20  30  20   5
BLAIRSVILLE     24  30  17  28 /  60  60  30  10
CARTERSVILLE    28  35  22  35 /  30  30  30   5
COLUMBUS        32  43  25  44 /  10  10   5   5
GAINESVILLE     28  34  22  33 /  30  20  20   5
MACON           31  43  25  44 /  20   5   5   5
ROME            28  35  21  35 /  30  40  30   5
PEACHTREE CITY  29  38  23  38 /  20  20   5   5
VIDALIA         34  46  28  47 /  20   5   0   5

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 4 AM TUESDAY TO 10 AM EST THURSDAY FOR
THE FOLLOWING ZONES: DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...PICKENS...TOWNS...UNION...WHITE.

WINTER WEATHER ADVISORY UNTIL 10 AM EST WEDNESDAY FOR THE
FOLLOWING ZONES: CATOOSA...DAWSON...FANNIN...GILMER...LUMPKIN...
MURRAY...TOWNS...UNION...WHITE...WHITFIELD.

&&

$$

SHORT TERM...BAKER
LONG TERM....41
AVIATION...BAKER


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.