Area Forecast Discussion
Issued by NWS Indianapolis, IN

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000
FXUS63 KIND 040238
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
938 PM EST TUE MAR 3 2015

.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 311 PM EST TUE MAR 3 2015

COLDER AIR WILL RETURN TO CENTRAL INDIANA FOR THE SECOND HALF OF THE
WORK WEEK. AS IT DOES...RAIN WILL CHANGE TO SNOW TONIGHT. SNOW WILL
FALL ACROSS PORTIONS OF THE AREA WEDNESDAY INTO EARLY
THURSDAY...WITH SIGNIFICANT ACCUMULATIONS POSSIBLE ACROSS FAR
SOUTHERN AREAS. HIGH PRESSURE WILL THEN PROVIDE DRY CONDITIONS WITH
A WARMING TREND THIS WEEKEND INTO EARLY NEXT WEEK.

&&

.NEAR TERM /OVERNIGHT/...

ISSUED AT 930 PM EST TUE MAR 3 2015

MINOR SOUTHWARD ADJUSTMENTS ON PRECIP...DRYING OUT NORTHERN
COUNTIES A BIT FASTER PRIOR TO MIDNIGHT.

STEADY RAIN EDGE HAS SAGGED SLIGHTLY SOUTH OF I-70. STILL ONE
MORE PATCH OF LIGHT RAIN OVER CENTRAL ILLINOIS TO FEED ALONG AND
JUST NORTH OF I-70 THROUGH MIDNIGHT OR SO.

DOUBTFUL ANY SNOW LIKELY TO COME WITH OVERNIGHT PRECIPITATION BUT
TEMPS WILL FALL ENOUGH THAT ANY LEFTOVER PRECIP NORTH OF I-70
COULD SEE A LITTLE MIX AFTER MIDNIGHT.

SOUTH OF I-70 STILL EXPECT VERY SLOW SOUTH MOVEMENT OF RAIN AREA
AND VERY SLOW FALL OF TEMPS SO MAINLY RAIN UNTIL A FEW HOURS PRIOR
TO DAYBREAK AND JUST BARELY REACHING FREEZING THEN.

&&

.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 311 PM EST TUE MAR 3 2015

FOCUS IS ON THREAT FOR HEAVY SNOW ACROSS THE SOUTHERN FORECAST AREA
WEDNESDAY AND WEDNESDAY NIGHT. OVERALL THE MODELS ARE NOT TOO FAR
APART FROM EACH OTHER. THERE ARE SOME DIFFERENCES IN SNOW AMOUNTS
BUT THIS IS DUE IN PART TO A TIGHT GRADIENT EXPECTED. GENERALLY WENT
WITH A BLEND.

COLDER AIR WILL CONTINUE TO FLOW INTO THE AREA ON WEDNESDAY. THERE
MAY BE A MIX TO THE PRECIPITATION TYPE IN THE FAR SOUTH ON WEDNESDAY
BUT IT WOULD QUICKLY CHANGEOVER TO SNOW IN THE MORNING. ELSEWHERE
PRECIPITATION TYPE WILL BE SNOW.

FORCING INCREASES AGAIN DURING THE DAY WEDNESDAY AS A WAVE RIDES
ALONG THE COLD FRONT TO OUR SOUTH. ISENTROPIC LIFT CONTINUES...AND
OUR AREA GETS INTO THE RIGHT REAR QUADRANT OF AN UPPER JET WHICH
WILL PROVIDE ADDITIONAL LIFT. FRONTOGENETICAL FORCING WILL ALSO
INCREASE.

THE FOCUS FOR THE FORCING WILL BE TO THE SOUTH OF CENTRAL INDIANA
CLOSER TO THE FRONT. HOWEVER ENOUGH FORCING WILL BE ACROSS THE
SOUTHERN THIRD OF THE AREA TO GO LIKELY TO CATEGORICAL POPS
WEDNESDAY.

SIMILAR CONDITIONS CONTINUE WEDNESDAY NIGHT WITH BETTER POPS
SNEAKING A LITTLE FARTHER NORTH /STILL LIKELY TO CATEGORICAL
SOUTHEAST 1/3 OF THE AREA/. HOWEVER WITH THE CIRCULATION PROVIDED BY
THE UPPER JET EXPECT THE PRECIPITATION GRADIENT TO TIGHTEN EVEN
MORE. THE FAR NORTHWEST FORECAST AREA LOOKS TO BE DRY WEDNESDAY
NIGHT...WITH CHANCE POPS IN BETWEEN THAT AND THE HIGH POPS TO THE
SOUTH.

WITH PLENTY OF MOISTURE STILL AVAILABLE FOR THE SYSTEM...ESPECIALLY
ACROSS KENTUCKY...SIGNIFICANT SNOW AMOUNTS REMAIN POSSIBLE. THE
FACTORS MENTIONED ABOVE WILL PRODUCE A VERY TIGHT GRADIENT IN SNOW
AMOUNTS...GOING FROM LITTLE SNOW TO SIGNIFICANT SNOW IN A RELATIVELY
SMALL DISTANCE /ESPECIALLY CONSIDERING THE FRONTOGENETICAL FORCING/.

THE FAR SOUTHERN ROW OF COUNTIES IN CENTRAL INDIANA LOOK TO SEE THE
BEST CHANCE FOR SIGNIFICANT SNOW. HOWEVER WITH THE GRADIENT
MENTIONED ABOVE AM NOT CONFIDENT ENOUGH YET TO UPGRADE TO A WARNING.
AFTER COORDINATING WITH SURROUNDING OFFICES HAVE DECIDED TO LEAVE
THE CURRENT WINTER STORM WATCH AS IS AND LET ADDITIONAL DATA ARRIVE
BEFORE DECIDING TO GO TO WARNING. FOR NOW WENT NEAR 6 INCHES STORM
TOTAL IN THIS ROW WITH AMOUNTS QUICKLY TAPERING OFF TO THE NORTH.
WENT 2-3 INCHES IN BLOOMINGTON/COLUMBUS AREA AND AROUND 1 INCH IN
INDY.

AFTER THE SYSTEM MOVES OUT EARLY THURSDAY WENT DRY FOR THE REMAINDER
OF THE SHORT TERM WITH HIGH PRESSURE MOVING IN. THE ARCTIC AIR WILL
PROVIDE WELL BELOW AVERAGE TEMPERATURES...WITH BELOW ZERO READINGS
POSSIBLE THURSDAY NIGHT.

GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES DURING THE
PERIOD.

&&

.LONG TERM /FRIDAY NIGHT THROUGH NEXT TUESDAY/...
ISSUED AT 311 PM EST TUE MAR 3 2015

MUCH QUIETER WEATHER WILL BE THE RULE DURING THE LONG TERM AS MODEL
ENSEMBLES INDICATE A MORE ZONAL AND SLOWLY PROGRESSIVE UPPER
FLOW OVER MUCH OF THE U.S.  THE MEAN TROUGHINESS INITIALLY OVER THE
EASTERN PARTS OF THE COUNTRY WILL LIFT TO THE NORTHEAST BY EARLY
NEXT WEEK AS AN UPPER RIDGE BUILDS EAST INTO THE PLAINS.

A COUPLE OF SHORT WAVE TROUGHS MAY PASS THROUGH THE AREA DURING THIS
PERIOD...ONE AROUND SATURDAY AND ANOTHER AROUND SUNDAY NIGHT INTO
NEXT MONDAY. A FEW ENSEMBLE MEMBERS INDICATE VERY LIGHT QPF WITH
EACH OF THESE FEATURES...SUGGESTING MINOR CHANCES FOR SOME LIGHT
SNOW. HOWEVER...CHANCES FOR MEASURABLE NOT HIGH ENOUGH TO INCLUDE
IN THE FORECAST AT THIS TIME. WILL KEEP THE EXTENDED DRY.

TEMPERATURES WILL STILL BE COLD FRIDAY NIGHT...BUT MODERATE OVER
REST OF THE LONG TERM AS 850 MB TEMPERATURES SLOWLY RISE.  BY DAY 7
HIGHS WILL REACH THE LOWER ACROSS OUR SOUTHWEST.  ALL MODELS
INDICATE A TRANSITION TO MORE SPRING LIKE WEATHER BY THE MIDDLE TO
LATER PORTIONS OF NEXT WEEK.

&&

.AVIATION /UPDATE FOR 040300Z IND TAF UPDATE/...

ISSUED AT 918 PM EST TUE MAR 3 2015

PULLED THE RAIN AND POOR VISIBILITY BASED ON TRENDS.

PREVIOUS DISCUSSION FOLLOWS...

IFR AND WORSE CONDITIONS SHOULD IMPROVE TO MVFR AFTER 07Z AT LAF
AND AFTER 10Z AT IND AND HUF BUT MAY NOT DO SO AT BMG THROUGH
TOMORROW AS A BAROCLINIC SETS UP ACROSS SOUTHERN INDIANA AND
KENTUCKY AIDED BY RIGHT REAR PORTION OF UPPER JET. LINGER RAIN
SHOULD MIX WITH A CHANGE TO SNOW AFTER 02Z AT LAF BEFORE ENDING
SHORTLY AFTER. MEANWHILE...MEDIUM CONFIDENCE...THE OTHER TERMINALS
SHOULD SEE THE CHANGEOVER AFTER 06Z. THE SNOW MAY END FOR A FEW
HOURS TOWARD DAYBREAK AT IND AND HUF BEFORE RETURNING MIDDAY
TOMORROW.

SOUTHWEST WINDS 10 TO 15 KNOTS AND GUSTING TO NEAR 20 KNOTS SHOULD
SLOWLY DROP OFF AND BECOME NORTHWEST AS A COLD FRONT MOVES THROUGH
CENTRAL INDIANA FROM THE NORTHWEST IN THE 07Z-09Z TIME FRAME.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
MORNING FOR INZ067>072.

&&

$$

SYNOPSIS...50
NEAR TERM...TUCEK
SHORT TERM...50
LONG TERM....JH
AVIATION...MK

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