Area Forecast Discussion
Issued by NWS Nashville, TN

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
FXUS64 KOHX 011743
AFDOHX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1143 AM CST SUN FEB 1 2015

.UPDATE...

18Z TAF DISCUSSION.

&&

.AVIATION...

-SHRA WILL CONTINUE AT AIRPORTS THROUGH THIS EVENING BEFORE
MOISTURE GETS SHUNTED OFF TO THE EAST. LINGERING -SHRA WILL
CHANGE TO -RASN AT CSV AROUND 09Z AS COLDER AIR MOVES IN. CURRENT
VFR/MVFR CIGS/VIS WILL DETERIORATE TO MVFR AT ALL TAF SITES AND
REMAIN THERE THROUGH THE FORECAST PERIOD. GUSTY SOUTH WINDS UP TO
25 KTS WILL GRADUALLY VEER AND BECOME SOUTHWEST TONIGHT AND
NORTHWEST TOMORROW.

SHAMBURGER

&&

.PREV DISCUSSION... /ISSUED 1008 AM CST SUN FEB 1 2015/

UPDATE...

LATEST RADAR IMAGERY SHOWS HAS OVERSPREAD ALL OF MIDDLE
TENNESSEE...ALTHOUGH PRECIP MAY STILL NOT BE REACHING THE GROUND
ON PARTS OF THE PLATEAU DUE TO THE VERY DRY AIR BELOW 700MB PER
12Z OHX SOUNDING. THIS WILL BE SHORT LIVED HOWEVER AS LOW LEVELS
CONTINUE TO SATURATE THIS MORNING AND ADDITIONAL RAIN MOVES IN
FROM THE SOUTHWEST. THUS WILL UPDATE TO SHOW 100 POPS THROUGH THE
AFTERNOON HOURS. REST OF FORECAST LOOKS TO BE ON TRACK WITH NO
CHANGES MADE. FOR TONIGHT...12Z NAM MOVES MOISTURE OUT OF THE
FORECAST AREA VERY QUICKLY OVERNIGHT...WITH LITTLE OR NO SNOW FOR
MOST AREAS AND ONLY UP TO ONE HALF INCH ON THE PLATEAU. WILL TAKE
A CLOSER LOOK AT SNOW POTENTIAL FOR TONIGHT WITH THE FULL 12Z
MODEL SUITE FOR THE AFTERNOON PACKAGE.

SHAMBURGER

PREV DISCUSSION... /ISSUED 534 AM CST SUN FEB 1 2015/

UPDATE...ADDED AVIATION SECTION FOR 12Z TAF`S.

AVIATION...BNA/CKV/CSV...SURFACE LOW IS SITUATED OVER EASTERN KS
THIS HOUR WITH A COLD FRONT TRAILING SW`WD FROM THE LOW.
PRESSURE GRADIENT HAS STRENGTHENED SIGNIFICANTLY ACROSS MIDDLE
TENNESSEE THE LAST SEVERAL HOURS, ALTHOUGH THE BOUNDARY LAYER
REMAINS DRY. A SOLID MID-LEVEL OVERCAST COVERS THE AREA, AND CIGS
WON`T DROP APPRECIABLY UNTIL PRECIPITATION BEGINS LATER THIS
MORNING. BY AFTERNOON, EXPECT CIGS TO DROP TO MVFR AS RAIN
INTENSIFIES, AND THIS WILL LIKELY LAST INTO THE EVENING.
PRECIPITATION WILL TAPER OFF LATER IN THE EVENING, WITH SOME SNOW
POSSIBLY MIXING IN LATE FOLLOWING FROPA.

PREV DISCUSSION... /ISSUED 321 AM CST SUN FEB 1 2015/

DISCUSSION...

ANOTHER CHALLENGING FORECAST IS ON MIDDLE TN`S DOORSTEP THIS MORNING
AS A DEEPENING SURFACE LOW DEVELOPS OFF TO OUR WEST.  THIS SYSTEM
WILL BRING RAINS BACK TO THE MID-STATE TODAY AND OFFER UP ANOTHER
OPPORTUNITY FOR US TO SEE SOME WINTER WEATHER TONIGHT.

MOISTURE IS SLOWLY BUILDING ACROSS THE REGION THIS MORNING IN
RESPONSE TO SAID SURFACE LOW AND WHILE RAINS SHOULD HOLD OFF UNTIL
SUNRISE...LIGHT TO MODERATE RAIN WILL MOVE IN LATER THIS MORNING.
THE ATMOSPHERE WILL REMAIN FAIRLY STABLE THROUGHOUT THIS EVENT SO
THERE WILL BE NO MENTION OF THUNDER BUT RAIN TOTALS SHOULD REACH
NEAR ONE INCH FOR MANY BEFORE MIDNIGHT TONIGHT.

AS IS TYPICALLY THE CASE THIS TIME OF THE YEAR...WE RUN THE RISK OF
COLD AIR RACING IN BEHIND THESE SYSTEMS AND COMING TOGETHER WITH THE
PRECIPITATION BEFORE IT LEAVES THE AREA.  THIS ONE WILL BE NO
DIFFERENT...IN FACT...WE MAY SEE A LULL IN THE PRECIP AFTER 00Z THIS
EVENING...THEN SOME ADDITIONAL MOISTURE WILL MIX IN WITH THE WRAP
AROUND COLD AIR.  CONFIDENCE IS LOW PERTAINING TO THE AMOUNT OF THE
WHITE STUFF WE WILL ENCOUNTER BUT AFTER 06Z TONIGHT FORECAST
SOUNDINGS QUICKLY BECOME SUPPORTIVE OF SNOWFALL.  MODELS RUN THE
GAMBIT IN REGARDS TO QPF TONIGHT SO I`M RUNNING WITH A MEDIAN AMOUNT
ACROSS MIDDLE TN...WITH A DUSTING TO QUARTER INCH WEST OF THE
PLATEAU AND UP TO A HALF INCH ON THE PLATEAU.   THE SNOWFALL ON THE
CUMBERLAND PLATEAU LIKELY WON`T START ACCUMULATING UNTIL CLOSE TO
SUNRISE BECAUSE OF HOW WET IT WILL BE...SO I HAVE LEFT MOST OF THEIR
TOTALS TO THE POST-12Z MONDAY MORNING TIME FRAME.

IN ADDITION TO THE SNOWFALL...WE WILL LIKELY HAVE TO DEAL WITH SOME
PATCHY ROAD ICING MONDAY MORNING.  WHILE IT WILL BE BREEZY
THROUGHOUT THIS EVENT...THERE WILL LIKELY HAVE BEEN ENOUGH RAINFALL
SO THAT ROADS WON`T HAVE AN OPPORTUNITY TO COMPLETELY DRY OUT BEFORE
TEMPERATURES FALL BELOW FREEZING EARLY MONDAY MORNING.

TIMING WILL BE EVERYTHING FOR THIS EVENT...BUT NEEDLESS TO
SAY...THERE IS LOW CONFIDENCE REGARDING SNOW AMOUNTS.  SOME SPOTS ON
THE PLATEAU COULD SEE CLOSER TO ONE INCH SO BE PREPARED FOR THE
POSSIBILITY OF TODAY`S SPECIAL WEATHER STATEMENT TO BE UPGRADED TO A
WINTER WEATHER ADVISORY.

TEMPERATURES WILL STRUGGLE TO GET NEAR 40 ON MONDAY AND AS HIGH
PRESSURE SETTLES INTO THE REGION MONDAY NIGHT WE WOULD USUALLY
EXPECT TEMPERATURES TO FALL OFF FOR TUESDAY MORNING.  THE WRENCH IN
THIS WOULD BE A DECENT CLOUD DECK MOVING IN MONDAY NIGHT.  BECAUSE
OF THIS...I HAVE GONE A FEW DEGREES ABOVE GUIDANCE...ESP IN THE
WEST.

DRY CONDITIONS TUESDAY AND WEDNESDAY LEAD US INTO THURSDAY.  THE
EURO...WHICH HAS BEEN THE DRIER OF THE TWO EXTENDED SOLUTIONS IS
FINALLY COMING AROUND TO THE GFS AGAIN.  THIS SEEMS TO BE A RUNNING
TREND LATELY.  THE DOWNSIDE OF THIS...WE COULD BE IN FOR MORE WINTRY
WEATHER THURSDAY.  TEMPERATURE PROFILES BECOME SUPPORTIVE OF SNOW BY
12Z THURSDAY AND WHILE QPFS AREN`T IMPRESSIVE WITH THE WEAK FRONT
THAT PUSHES INTO THE AREA...SOME SNOW IS STILL POSSIBLE DURING THE
DAY ON THURSDAY.

REMARKABLY...THERE IS DECENT AGREEMENT IN THE EXTENDED FOR YET
ANOTHER SHORTWAVE TO DIG INTO THE REGION BY THE END OF NEXT
WEEKEND.  HAVE STARTED THIS ONE OUT WITH SOME DAY 8 CHANCE POPS.

UNGER

AVIATION...06Z TAF DISCUSSION.

DETERIORATING CONDITIONS ON TAP THIS TAF CYCLE AS STRONG SFC LOW
MOVES FROM THE PLAINS INTO THE OH VALLEY AND BRINGS A COLD FRONT
ACROSS THE MID-SOUTH TOMORROW NIGHT. STRONG LOW-LEVEL JET MAY
INITIALLY PRODUCE WIND SHEAR TONIGHT BEFORE SFC WINDS GUST
20-30 KTS AFT 12Z. PCPN WILL START 14Z-16Z RANGE CKV AND SPREAD
QUICKLY EAST. CIGS/VSBYS WILL RESPOND BY LOWERING THROUGHOUT THE
DAY...WITH SUN AFTERNOON/EVENING MVFR/IFR RANGE...POSSIBLY LIFR
CSV.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

55




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